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Raffi Hovasapian

Raffi Hovasapian

Monosaccharides

Slide Duration:

Table of Contents

I. Preliminaries on Aqueous Chemistry
Aqueous Solutions & Concentration

39m 57s

Intro
0:00
Aqueous Solutions and Concentration
0:46
Definition of Solution
1:28
Example: Sugar Dissolved in Water
2:19
Example: Salt Dissolved in Water
3:04
A Solute Does Not Have to Be a Solid
3:37
A Solvent Does Not Have to Be a Liquid
5:02
Covalent Compounds
6:55
Ionic Compounds
7:39
Example: Table Sugar
9:12
Example: MgCl₂
10:40
Expressing Concentration: Molarity
13:42
Example 1
14:47
Example 1: Question
14:50
Example 1: Solution
15:40
Another Way to Express Concentration
22:01
Example 2
24:00
Example 2: Question
24:01
Example 2: Solution
24:49
Some Other Ways of Expressing Concentration
27:52
Example 3
29:30
Example 3: Question
29:31
Example 3: Solution
31:02
Dilution & Osmotic Pressure

38m 53s

Intro
0:00
Dilution
0:45
Definition of Dilution
0:46
Example 1: Question
2:08
Example 1: Basic Dilution Equation
4:20
Example 1: Solution
5:31
Example 2: Alternative Approach
12:05
Osmotic Pressure
14:34
Colligative Properties
15:02
Recall: Covalent Compounds and Soluble Ionic Compounds
17:24
Properties of Pure Water
19:42
Addition of a Solute
21:56
Osmotic Pressure: Conceptual Example
24:00
Equation for Osmotic Pressure
29:30
Example of 'i'
31:38
Example 3
32:50
More on Osmosis

29m 1s

Intro
0:00
More on Osmosis
1:25
Osmotic Pressure
1:26
Example 1: Molar Mass of Protein
5:25
Definition, Equation, and Unit of Osmolarity
13:13
Example 2: Osmolarity
15:19
Isotonic, Hypertonic, and Hypotonic
20:20
Example 3
22:20
More on Isotonic, Hypertonic, and Hypotonic
26:14
Osmosis vs. Osmotic Pressure
27:56
Acids & Bases

39m 11s

Intro
0:00
Acids and Bases
1:16
Let's Begin With H₂O
1:17
P-Scale
4:22
Example 1
6:39
pH
9:43
Strong Acids
11:10
Strong Bases
13:52
Weak Acids & Bases Overview
14:32
Weak Acids
15:49
Example 2: Phosphoric Acid
19:30
Weak Bases
24:50
Weak Base Produces Hydroxide Indirectly
25:41
Example 3: Pyridine
29:07
Acid Form and Base Form
32:02
Acid Reaction
35:50
Base Reaction
36:27
Ka, Kb, and Kw
37:14
Titrations and Buffers

41m 33s

Intro
0:00
Titrations
0:27
Weak Acid
0:28
Rearranging the Ka Equation
1:45
Henderson-Hasselbalch Equation
3:52
Fundamental Reaction of Acids and Bases
5:36
The Idea Behind a Titration
6:27
Let's Look at an Acetic Acid Solution
8:44
Titration Curve
17:00
Acetate
23:57
Buffers
26:57
Introduction to Buffers
26:58
What is a Buffer?
29:40
Titration Curve & Buffer Region
31:44
How a Buffer Works: Adding OH⁻
34:44
How a Buffer Works: Adding H⁺
35:58
Phosphate Buffer System
38:02
Example Problems with Acids, Bases & Buffers

44m 19s

Intro
0:00
Example 1
1:21
Example 1: Properties of Glycine
1:22
Example 1: Part A
3:40
Example 1: Part B
4:40
Example 2
9:02
Example 2: Question
9:03
Example 2: Total Phosphate Concentration
12:23
Example 2: Final Solution
17:10
Example 3
19:34
Example 3: Question
19:35
Example 3: pH Before
22:18
Example 3: pH After
24:24
Example 3: New pH
27:54
Example 4
30:00
Example 4: Question
30:01
Example 4: Equilibria
32:52
Example 4: 1st Reaction
38:04
Example 4: 2nd Reaction
39:53
Example 4: Final Solution
41:33
Hydrolysis & Condensation Reactions

18m 45s

Intro
0:00
Hydrolysis and Condensation Reactions
0:50
Hydrolysis
0:51
Condensation
2:42
Example 1: Hydrolysis of Ethyl Acetate
4:52
Example 2: Condensation of Acetic Acid with Ethanol
8:42
Example 3
11:18
Example 4: Formation & Hydrolysis of a Peptide Bond Between the Amino Acids Alanine & Serine
14:56
II. Amino Acids & Proteins: Primary Structure
Amino Acids

38m 19s

Intro
0:00
Amino Acids
0:17
Proteins & Amino Acids
0:18
Difference Between Amino Acids
4:20
α-Carbon
7:08
Configuration in Biochemistry
10:43
L-Glyceraldehyde & Fischer Projection
12:32
D-Glyceraldehyde & Fischer Projection
15:31
Amino Acids in Biological Proteins are the L Enantiomer
16:50
L-Amino Acid
18:04
L-Amino Acids Correspond to S-Enantiomers in the RS System
20:10
Classification of Amino Acids
22:53
Amino Acids With Non-Polar R Groups
26:45
Glycine
27:00
Alanine
27:48
Valine
28:15
Leucine
28:58
Proline
31:08
Isoleucine
32:42
Methionine
33:43
Amino Acids With Aromatic R Groups
34:33
Phenylalanine
35:26
Tyrosine
36:02
Tryptophan
36:32
Amino Acids, Continued

27m 14s

Intro
0:00
Amino Acids With Positively Charged R Groups
0:16
Lysine
0:52
Arginine
1:55
Histidine
3:15
Amino Acids With Negatively Charged R Groups
6:28
Aspartate
6:58
Glutamate
8:11
Amino Acids With Uncharged, but Polar R Groups
8:50
Serine
8:51
Threonine
10:21
Cysteine
11:06
Asparagine
11:35
Glutamine
12:44
More on Amino Acids
14:18
Cysteine Dimerizes to Form Cystine
14:53
Tryptophan, Tyrosine, and Phenylalanine
19:07
Other Amino Acids
20:53
Other Amino Acids: Hydroxy Lysine
22:34
Other Amino Acids: r-Carboxy Glutamate
25:37
Acid/Base Behavior of Amino Acids

48m 28s

Intro
0:00
Acid/Base Behavior of Amino Acids
0:27
Acid/Base Behavior of Amino Acids
0:28
Let's Look at Alanine
1:57
Titration of Acidic Solution of Alanine with a Strong Base
2:51
Amphoteric Amino Acids
13:24
Zwitterion & Isoelectric Point
16:42
Some Amino Acids Have 3 Ionizable Groups
20:35
Example: Aspartate
24:44
Example: Tyrosine
28:50
Rule of Thumb
33:04
Basis for the Rule
35:59
Example: Describe the Degree of Protonation for Each Ionizable Group
38:46
Histidine is Special
44:58
Peptides & Proteins

45m 18s

Intro
0:00
Peptides and Proteins
0:15
Introduction to Peptides and Proteins
0:16
Formation of a Peptide Bond: The Bond Between 2 Amino Acids
1:44
Equilibrium
7:53
Example 1: Build the Following Tripeptide Ala-Tyr-Ile
9:48
Example 1: Shape Structure
15:43
Example 1: Line Structure
17:11
Peptides Bonds
20:08
Terms We'll Be Using Interchangeably
23:14
Biological Activity & Size of a Peptide
24:58
Multi-Subunit Proteins
30:08
Proteins and Prosthetic Groups
32:13
Carbonic Anhydrase
37:35
Primary, Secondary, Tertiary, and Quaternary Structure of Proteins
40:26
Amino Acid Sequencing of a Peptide Chain

42m 47s

Intro
0:00
Amino Acid Sequencing of a Peptide Chain
0:30
Amino Acid Sequence and Its Structure
0:31
Edman Degradation: Overview
2:57
Edman Degradation: Reaction - Part 1
4:58
Edman Degradation: Reaction - Part 2
10:28
Edman Degradation: Reaction - Part 3
13:51
Mechanism Step 1: PTC (Phenylthiocarbamyl) Formation
19:01
Mechanism Step 2: Ring Formation & Peptide Bond Cleavage
23:03
Example: Write Out the Edman Degradation for the Tripeptide Ala-Tyr-Ser
30:29
Step 1
30:30
Step 2
34:21
Step 3
36:56
Step 4
38:28
Step 5
39:24
Step 6
40:44
Sequencing Larger Peptides & Proteins

1h 2m 33s

Intro
0:00
Sequencing Larger Peptides and Proteins
0:28
Identifying the N-Terminal Amino Acids With the Reagent Fluorodinitrobenzene (FDNB)
0:29
Sequencing Longer Peptides & Proteins Overview
5:54
Breaking Peptide Bond: Proteases and Chemicals
8:16
Some Enzymes/Chemicals Used for Fragmentation: Trypsin
11:14
Some Enzymes/Chemicals Used for Fragmentation: Chymotrypsin
13:02
Some Enzymes/Chemicals Used for Fragmentation: Cyanogen Bromide
13:28
Some Enzymes/Chemicals Used for Fragmentation: Pepsin
13:44
Cleavage Location
14:04
Example: Chymotrypsin
16:44
Example: Pepsin
18:17
More on Sequencing Larger Peptides and Proteins
19:29
Breaking Disulfide Bonds: Performic Acid
26:08
Breaking Disulfide Bonds: Dithiothreitol Followed by Iodoacetate
31:04
Example: Sequencing Larger Peptides and Proteins
37:03
Part 1 - Breaking Disulfide Bonds, Hydrolysis and Separation
37:04
Part 2 - N-Terminal Identification
44:16
Part 3 - Sequencing Using Pepsin
46:43
Part 4 - Sequencing Using Cyanogen Bromide
52:02
Part 5 - Final Sequence
56:48
Peptide Synthesis (Merrifield Process)

49m 12s

Intro
0:00
Peptide Synthesis (Merrifield Process)
0:31
Introduction to Synthesizing Peptides
0:32
Merrifield Peptide Synthesis: General Scheme
3:03
So What Do We Do?
6:07
Synthesis of Protein in the Body Vs. The Merrifield Process
7:40
Example: Synthesis of Ala-Gly-Ser
9:21
Synthesis of Ala-Gly-Ser: Reactions Overview
11:41
Synthesis of Ala-Gly-Ser: Reaction 1
19:34
Synthesis of Ala-Gly-Ser: Reaction 2
24:34
Synthesis of Ala-Gly-Ser: Reaction 3
27:34
Synthesis of Ala-Gly-Ser: Reaction 4 & 4a
28:48
Synthesis of Ala-Gly-Ser: Reaction 5
33:38
Synthesis of Ala-Gly-Ser: Reaction 6
36:45
Synthesis of Ala-Gly-Ser: Reaction 7 & 7a
37:44
Synthesis of Ala-Gly-Ser: Reaction 8
39:47
Synthesis of Ala-Gly-Ser: Reaction 9 & 10
43:23
Chromatography: Eluent, Stationary Phase, and Eluate
45:55
More Examples with Amino Acids & Peptides

54m 31s

Intro
0:00
Example 1
0:22
Data
0:23
Part A: What is the pI of Serine & Draw the Correct Structure
2:11
Part B: How Many mL of NaOH Solution Have Been Added at This Point (pI)?
5:27
Part C: At What pH is the Average Charge on Serine
10:50
Part D: Draw the Titration Curve for This Situation
14:50
Part E: The 10 mL of NaOH Added to the Solution at the pI is How Many Equivalents?
17:35
Part F: Serine Buffer Solution
20:22
Example 2
23:04
Data
23:05
Part A: Calculate the Minimum Molar Mass of the Protein
25:12
Part B: How Many Tyr Residues in this Protein?
28:34
Example 3
30:08
Question
30:09
Solution
34:30
Example 4
48:46
Question
48:47
Solution
49:50
III. Proteins: Secondary, Tertiary, and Quaternary Structure
Alpha Helix & Beta Conformation

50m 52s

Intro
0:00
Alpha Helix and Beta Conformation
0:28
Protein Structure Overview
0:29
Weak interactions Among the Amino Acid in the Peptide Chain
2:11
Two Principals of Folding Patterns
4:56
Peptide Bond
7:00
Peptide Bond: Resonance
9:46
Peptide Bond: φ Bond & ψ Bond
11:22
Secondary Structure
15:08
α-Helix Folding Pattern
17:28
Illustration 1: α-Helix Folding Pattern
19:22
Illustration 2: α-Helix Folding Pattern
21:39
β-Sheet
25:16
β-Conformation
26:04
Parallel & Anti-parallel
28:44
Parallel β-Conformation Arrangement of the Peptide Chain
30:12
Putting Together a Parallel Peptide Chain
35:16
Anti-Parallel β-Conformation Arrangement
37:42
Tertiary Structure
45:03
Quaternary Structure
45:52
Illustration 3: Myoglobin Tertiary Structure & Hemoglobin Quaternary Structure
47:13
Final Words on Alpha Helix and Beta Conformation
48:34
IV. Proteins: Function
Protein Function I: Ligand Binding & Myoglobin

51m 36s

Intro
0:00
Protein Function I: Ligand Binding & Myoglobin
0:30
Ligand
1:02
Binding Site
2:06
Proteins are Not Static or Fixed
3:36
Multi-Subunit Proteins
5:46
O₂ as a Ligand
7:21
Myoglobin, Protoporphyrin IX, Fe ²⁺, and O₂
12:54
Protoporphyrin Illustration
14:25
Myoglobin With a Heme Group Illustration
17:02
Fe²⁺ has 6 Coordination Sites & Binds O₂
18:10
Heme
19:44
Myoglobin Overview
22:40
Myoglobin and O₂ Interaction
23:34
Keq or Ka & The Measure of Protein's Affinity for Its Ligand
26:46
Defining α: Fraction of Binding Sites Occupied
32:52
Graph: α vs. [L]
37:33
For The Special Case of α = 0.5
39:01
Association Constant & Dissociation Constant
43:54
α & Kd
45:15
Myoglobin's Binding of O₂
48:20
Protein Function II: Hemoglobin

1h 3m 36s

Intro
0:00
Protein Function II: Hemoglobin
0:14
Hemoglobin Overview
0:15
Hemoglobin & Its 4 Subunits
1:22
α and β Interactions
5:18
Two Major Conformations of Hb: T State (Tense) & R State (Relaxed)
8:06
Transition From The T State to R State
12:03
Binding of Hemoglobins & O₂
14:02
Binding Curve
18:32
Hemoglobin in the Lung
27:28
Signoid Curve
30:13
Cooperative Binding
32:25
Hemoglobin is an Allosteric Protein
34:26
Homotropic Allostery
36:18
Describing Cooperative Binding Quantitatively
38:06
Deriving The Hill Equation
41:52
Graphing the Hill Equation
44:43
The Slope and Degree of Cooperation
46:25
The Hill Coefficient
49:48
Hill Coefficient = 1
51:08
Hill Coefficient < 1
55:55
Where the Graph Hits the x-axis
56:11
Graph for Hemoglobin
58:02
Protein Function III: More on Hemoglobin

1h 7m 16s

Intro
0:00
Protein Function III: More on Hemoglobin
0:11
Two Models for Cooperative Binding: MWC & Sequential Model
0:12
MWC Model
1:31
Hemoglobin Subunits
3:32
Sequential Model
8:00
Hemoglobin Transports H⁺ & CO₂
17:23
Binding Sites of H⁺ and CO₂
19:36
CO₂ is Converted to Bicarbonate
23:28
Production of H⁺ & CO₂ in Tissues
27:28
H⁺ & CO₂ Binding are Inversely Related to O₂ Binding
28:31
The H⁺ Bohr Effect: His¹⁴⁶ Residue on the β Subunits
33:31
Heterotropic Allosteric Regulation of O₂ Binding by 2,3-Biphosphoglycerate (2,3 BPG)
39:53
Binding Curve for 2,3 BPG
56:21
V. Enzymes
Enzymes I

41m 38s

Intro
0:00
Enzymes I
0:38
Enzymes Overview
0:39
Cofactor
4:38
Holoenzyme
5:52
Apoenzyme
6:40
Riboflavin, FAD, Pyridoxine, Pyridoxal Phosphate Structures
7:28
Carbonic Anhydrase
8:45
Classification of Enzymes
9:55
Example: EC 1.1.1.1
13:04
Reaction of Oxidoreductases
16:23
Enzymes: Catalysts, Active Site, and Substrate
18:28
Illustration of Enzymes, Substrate, and Active Site
27:22
Catalysts & Activation Energies
29:57
Intermediates
36:00
Enzymes II

44m 2s

Intro
0:00
Enzymes II: Transitions State, Binding Energy, & Induced Fit
0:18
Enzymes 'Fitting' Well With The Transition State
0:20
Example Reaction: Breaking of a Stick
3:40
Another Energy Diagram
8:20
Binding Energy
9:48
Enzymes Specificity
11:03
Key Point: Optimal Interactions Between Substrate & Enzymes
15:15
Induced Fit
16:25
Illustrations: Induced Fit
20:58
Enzymes II: Catalytic Mechanisms
22:17
General Acid/Base Catalysis
23:56
Acid Form & Base Form of Amino Acid: Glu &Asp
25:26
Acid Form & Base Form of Amino Acid: Lys & Arg
26:30
Acid Form & Base Form of Amino Acid: Cys
26:51
Acid Form & Base Form of Amino Acid: His
27:30
Acid Form & Base Form of Amino Acid: Ser
28:16
Acid Form & Base Form of Amino Acid: Tyr
28:30
Example: Phosphohexose Isomerase
29:20
Covalent Catalysis
34:19
Example: Glyceraldehyde 3-Phosphate Dehydrogenase
35:34
Metal Ion Catalysis: Isocitrate Dehydrogenase
38:45
Function of Mn²⁺
42:15
Enzymes III: Kinetics

56m 40s

Intro
0:00
Enzymes III: Kinetics
1:40
Rate of an Enzyme-Catalyzed Reaction & Substrate Concentration
1:41
Graph: Substrate Concentration vs. Reaction Rate
10:43
Rate At Low and High Substrate Concentration
14:26
Michaelis & Menten Kinetics
20:16
More On Rate & Concentration of Substrate
22:46
Steady-State Assumption
26:02
Rate is Determined by How Fast ES Breaks Down to Product
31:36
Total Enzyme Concentration: [Et] = [E] + [ES]
35:35
Rate of ES Formation
36:44
Rate of ES Breakdown
38:40
Measuring Concentration of Enzyme-Substrate Complex
41:19
Measuring Initial & Maximum Velocity
43:43
Michaelis & Menten Equation
46:44
What Happens When V₀ = (1/2) Vmax?
49:12
When [S] << Km
53:32
When [S] >> Km
54:44
Enzymes IV: Lineweaver-Burk Plots

20m 37s

Intro
0:00
Enzymes IV: Lineweaver-Burk Plots
0:45
Deriving The Lineweaver-Burk Equation
0:46
Lineweaver-Burk Plots
3:55
Example 1: Carboxypeptidase A
8:00
More on Km, Vmax, and Enzyme-catalyzed Reaction
15:54
Enzymes V: Enzyme Inhibition

51m 37s

Intro
0:00
Enzymes V: Enzyme Inhibition Overview
0:42
Enzyme Inhibitors Overview
0:43
Classes of Inhibitors
2:32
Competitive Inhibition
3:08
Competitive Inhibition
3:09
Michaelis & Menten Equation in the Presence of a Competitive Inhibitor
7:40
Double-Reciprocal Version of the Michaelis & Menten Equation
14:48
Competitive Inhibition Graph
16:37
Uncompetitive Inhibition
19:23
Uncompetitive Inhibitor
19:24
Michaelis & Menten Equation for Uncompetitive Inhibition
22:10
The Lineweaver-Burk Equation for Uncompetitive Inhibition
26:04
Uncompetitive Inhibition Graph
27:42
Mixed Inhibition
30:30
Mixed Inhibitor
30:31
Double-Reciprocal Version of the Equation
33:34
The Lineweaver-Burk Plots for Mixed Inhibition
35:02
Summary of Reversible Inhibitor Behavior
38:00
Summary of Reversible Inhibitor Behavior
38:01
Note: Non-Competitive Inhibition
42:22
Irreversible Inhibition
45:15
Irreversible Inhibition
45:16
Penicillin & Transpeptidase Enzyme
46:50
Enzymes VI: Regulatory Enzymes

51m 23s

Intro
0:00
Enzymes VI: Regulatory Enzymes
0:45
Regulatory Enzymes Overview
0:46
Example: Glycolysis
2:27
Allosteric Regulatory Enzyme
9:19
Covalent Modification
13:08
Two Other Regulatory Processes
16:28
Allosteric Regulation
20:58
Feedback Inhibition
25:12
Feedback Inhibition Example: L-Threonine → L-Isoleucine
26:03
Covalent Modification
27:26
Covalent Modulators: -PO₃²⁻
29:30
Protein Kinases
31:59
Protein Phosphatases
32:47
Addition/Removal of -PO₃²⁻ and the Effect on Regulatory Enzyme
33:36
Phosphorylation Sites of a Regulatory Enzyme
38:38
Proteolytic Cleavage
41:48
Zymogens: Chymotrypsin & Trypsin
43:58
Enzymes That Use More Than One Regulatory Process: Bacterial Glutamine Synthetase
48:59
Why The Complexity?
50:27
Enzymes VII: Km & Kcat

54m 49s

Intro
0:00
Km
1:48
Recall the Michaelis–Menten Equation
1:49
Km & Enzyme's Affinity
6:18
Rate Forward, Rate Backward, and Equilibrium Constant
11:08
When an Enzyme's Affinity for Its Substrate is High
14:17
More on Km & Enzyme Affinity
17:29
The Measure of Km Under Michaelis–Menten kinetic
23:19
Kcat (First-order Rate Constant or Catalytic Rate Constant)
24:10
Kcat: Definition
24:11
Kcat & The Michaelis–Menten Postulate
25:18
Finding Vmax and [Et}
27:27
Units for Vmax and Kcat
28:26
Kcat: Turnover Number
28:55
Michaelis–Menten Equation
32:12
Km & Kcat
36:37
Second Order Rate Equation
36:38
(Kcat)/(Km): Overview
39:22
High (Kcat)/(Km)
40:20
Low (Kcat)/(Km)
43:16
Practical Big Picture
46:28
Upper Limit to (Kcat)/(Km)
48:56
More On Kcat and Km
49:26
VI. Carbohydrates
Monosaccharides

1h 17m 46s

Intro
0:00
Monosaccharides
1:49
Carbohydrates Overview
1:50
Three Major Classes of Carbohydrates
4:48
Definition of Monosaccharides
5:46
Examples of Monosaccharides: Aldoses
7:06
D-Glyceraldehyde
7:39
D-Erythrose
9:00
D-Ribose
10:10
D-Glucose
11:20
Observation: Aldehyde Group
11:54
Observation: Carbonyl 'C'
12:30
Observation: D & L Naming System
12:54
Examples of Monosaccharides: Ketose
16:54
Dihydroxy Acetone
17:28
D-Erythrulose
18:30
D-Ribulose
19:49
D-Fructose
21:10
D-Glucose Comparison
23:18
More information of Ketoses
24:50
Let's Look Closer at D-Glucoses
25:50
Let's Look At All the D-Hexose Stereoisomers
31:22
D-Allose
32:20
D-Altrose
33:01
D-Glucose
33:39
D-Gulose
35:00
D-Mannose
35:40
D-Idose
36:42
D-Galactose
37:14
D-Talose
37:42
Epimer
40:05
Definition of Epimer
40:06
Example of Epimer: D-Glucose, D-Mannose, and D-Galactose
40:57
Hemiacetal or Hemiketal
44:36
Hemiacetal/Hemiketal Overview
45:00
Ring Formation of the α and β Configurations of D-Glucose
50:52
Ring Formation of the α and β Configurations of Fructose
1:01:39
Haworth Projection
1:07:34
Pyranose & Furanose Overview
1:07:38
Haworth Projection: Pyranoses
1:09:30
Haworth Projection: Furanose
1:14:56
Hexose Derivatives & Reducing Sugars

37m 6s

Intro
0:00
Hexose Derivatives
0:15
Point of Clarification: Forming a Cyclic Sugar From a Linear Sugar
0:16
Let's Recall the α and β Anomers of Glucose
8:42
α-Glucose
10:54
Hexose Derivatives that Play Key Roles in Physiology Progression
17:38
β-Glucose
18:24
β-Glucosamine
18:48
N-Acetyl-β-Glucosamine
20:14
β-Glucose-6-Phosphate
22:22
D-Gluconate
24:10
Glucono-δ-Lactone
26:33
Reducing Sugars
29:50
Reducing Sugars Overview
29:51
Reducing Sugars Example: β-Galactose
32:36
Disaccharides

43m 32s

Intro
0:00
Disaccharides
0:15
Disaccharides Overview
0:19
Examples of Disaccharides & How to Name Them
2:49
Disaccharides Trehalose Overview
15:46
Disaccharides Trehalose: Flip
20:52
Disaccharides Trehalose: Spin
28:36
Example: Draw the Structure
33:12
Polysaccharides

39m 25s

Intro
0:00
Recap Example: Draw the Structure of Gal(α1↔β1)Man
0:38
Polysaccharides
9:46
Polysaccharides Overview
9:50
Homopolysaccharide
13:12
Heteropolysaccharide
13:47
Homopolysaccharide as Fuel Storage
16:23
Starch Has Two Types of Glucose Polymer: Amylose
17:10
Starch Has Two Types of Glucose Polymer: Amylopectin
18:04
Polysaccharides: Reducing End & Non-Reducing End
19:30
Glycogen
20:06
Examples: Structures of Polysaccharides
21:42
Let's Draw an (α1→4) & (α1→6) of Amylopectin by Hand.
28:14
More on Glycogen
31:17
Glycogen, Concentration, & The Concept of Osmolarity
35:16
Polysaccharides, Part 2

44m 15s

Intro
0:00
Polysaccharides
0:17
Example: Cellulose
0:34
Glycoside Bond
7:25
Example Illustrations
12:30
Glycosaminoglycans Part 1
15:55
Glycosaminoglycans Part 2
18:34
Glycosaminoglycans & Sulfate Attachments
22:42
β-D-N-Acetylglucosamine
24:49
β-D-N-AcetylGalactosamine
25:42
β-D-Glucuronate
26:44
β-L-Iduronate
27:54
More on Sulfate Attachments
29:49
Hylarunic Acid
32:00
Hyaluronates
39:32
Other Glycosaminoglycans
40:46
Glycoconjugates

44m 23s

Intro
0:00
Glycoconjugates
0:24
Overview
0:25
Proteoglycan
2:53
Glycoprotein
5:20
Glycolipid
7:25
Proteoglycan vs. Glycoprotein
8:15
Cell Surface Diagram
11:17
Proteoglycan Common Structure
14:24
Example: Chondroitin-4-Sulfate
15:06
Glycoproteins
19:50
The Monomers that Commonly Show Up in The Oligo Portions of Glycoproteins
28:02
N-Acetylneuraminic Acid
31:17
L-Furose
32:37
Example of an N-Linked Oligosaccharide
33:21
Cell Membrane Structure
36:35
Glycolipids & Lipopolysaccharide
37:22
Structure Example
41:28
More Example Problems with Carbohydrates

40m 22s

Intro
0:00
Example 1
1:09
Example 2
2:34
Example 3
5:12
Example 4
16:19
Question
16:20
Solution
17:25
Example 5
24:18
Question
24:19
Structure of 2,3-Di-O-Methylglucose
26:47
Part A
28:11
Part B
33:46
VII. Lipids
Fatty Acids & Triacylglycerols

54m 55s

Intro
0:00
Fatty Acids
0:32
Lipids Overview
0:34
Introduction to Fatty Acid
3:18
Saturated Fatty Acid
6:13
Unsaturated or Polyunsaturated Fatty Acid
7:07
Saturated Fatty Acid Example
7:46
Unsaturated Fatty Acid Example
9:06
Notation Example: Chain Length, Degree of Unsaturation, & Double Bonds Location of Fatty Acid
11:56
Example 1: Draw the Structure
16:18
Example 2: Give the Shorthand for cis,cis-5,8-Hexadecadienoic Acid
20:12
Example 3
23:12
Solubility of Fatty Acids
25:45
Melting Points of Fatty Acids
29:40
Triacylglycerols
34:13
Definition of Triacylglycerols
34:14
Structure of Triacylglycerols
35:08
Example: Triacylglycerols
40:23
Recall Ester Formation
43:57
The Body's Primary Fuel-Reserves
47:22
Two Primary Advantages to Storing Energy as Triacylglycerols Instead of Glycogen: Number 1
49:24
Two Primary Advantages to Storing Energy as Triacylglycerols Instead of Glycogen: Number 2
51:54
Membrane Lipids

38m 51s

Intro
0:00
Membrane Lipids
0:26
Definition of Membrane Lipids
0:27
Five Major Classes of Membrane Lipids
2:38
Glycerophospholipids
5:04
Glycerophospholipids Overview
5:05
The X Group
8:05
Example: Phosphatidyl Ethanolamine
10:51
Example: Phosphatidyl Choline
13:34
Phosphatidyl Serine
15:16
Head Groups
16:50
Ether Linkages Instead of Ester Linkages
20:05
Galactolipids
23:39
Galactolipids Overview
23:40
Monogalactosyldiacylglycerol: MGDG
25:17
Digalactosyldiacylglycerol: DGDG
28:13
Structure Examples 1: Lipid Bilayer
31:35
Structure Examples 2: Cross Section of a Cell
34:56
Structure Examples 3: MGDG & DGDG
36:28
Membrane Lipids, Part 2

38m 20s

Intro
0:00
Sphingolipids
0:11
Sphingolipid Overview
0:12
Sphingosine Structure
1:42
Ceramide
3:56
Subclasses of Sphingolipids Overview
6:00
Subclasses of Sphingolipids: Sphingomyelins
7:53
Sphingomyelins
7:54
Subclasses of Sphingolipids: Glycosphingolipid
12:47
Glycosphingolipid Overview
12:48
Cerebrosides & Globosides Overview
14:33
Example: Cerebrosides
15:43
Example: Globosides
17:14
Subclasses of Sphingolipids: Gangliosides
19:07
Gangliosides
19:08
Medical Application: Tay-Sachs Disease
23:34
Sterols
30:45
Sterols: Basic Structure
30:46
Important Example: Cholesterol
32:01
Structures Example
34:13
The Biologically Active Lipids

48m 36s

Intro
0:00
The Biologically Active Lipids
0:44
Phosphatidyl Inositol Structure
0:45
Phosphatidyl Inositol Reaction
3:24
Image Example
12:49
Eicosanoids
14:12
Arachidonic Acid & Membrane Lipid Containing Arachidonic Acid
18:41
Three Classes of Eicosanoids
20:42
Overall Structures
21:38
Prostagladins
22:56
Thromboxane
27:19
Leukotrienes
30:19
More On The Biologically Active Lipids
33:34
Steroid Hormones
33:35
Fat Soluble Vitamins
38:25
Vitamin D₃
40:40
Vitamin A
43:17
Vitamin E
45:12
Vitamin K
47:17
VIII. Energy & Biological Systems (Bioenergetics)
Thermodynamics, Free Energy & Equilibrium

45m 51s

Intro
0:00
Thermodynamics, Free Energy and Equilibrium
1:03
Reaction: Glucose + Pi → Glucose 6-Phosphate
1:50
Thermodynamics & Spontaneous Processes
3:31
In Going From Reactants → Product, a Reaction Wants to Release Heat
6:30
A Reaction Wants to Become More Disordered
9:10
∆H < 0
10:30
∆H > 0
10:57
∆S > 0
11:23
∆S <0
11:56
∆G = ∆H - T∆S at Constant Pressure
12:15
Gibbs Free Energy
15:00
∆G < 0
16:49
∆G > 0
17:07
Reference Frame For Thermodynamics Measurements
17:57
More On BioChemistry Standard
22:36
Spontaneity
25:36
Keq
31:45
Example: Glucose + Pi → Glucose 6-Phosphate
34:14
Example Problem 1
40:25
Question
40:26
Solution
41:12
More on Thermodynamics & Free Energy

37m 6s

Intro
0:00
More on Thermodynamics & Free Energy
0:16
Calculating ∆G Under Standard Conditions
0:17
Calculating ∆G Under Physiological Conditions
2:05
∆G < 0
5:39
∆G = 0
7:03
Reaction Moving Forward Spontaneously
8:00
∆G & The Maximum Theoretical Amount of Free Energy Available
10:36
Example Problem 1
13:11
Reactions That Have Species in Common
17:48
Example Problem 2: Part 1
20:10
Example Problem 2: Part 2- Enzyme Hexokinase & Coupling
25:08
Example Problem 2: Part 3
30:34
Recap
34:45
ATP & Other High-Energy Compounds

44m 32s

Intro
0:00
ATP & Other High-Energy Compounds
0:10
Endergonic Reaction Coupled With Exergonic Reaction
0:11
Major Theme In Metabolism
6:56
Why the ∆G°' for ATP Hydrolysis is Large & Negative
12:24
∆G°' for ATP Hydrolysis
12:25
Reason 1: Electrostatic Repulsion
14:24
Reason 2: Pi & Resonance Forms
15:33
Reason 3: Concentrations of ADP & Pi
17:32
ATP & Other High-Energy Compounds Cont'd
18:48
More On ∆G°' & Hydrolysis
18:49
Other Compounds That Have Large Negative ∆G°' of Hydrolysis: Phosphoenol Pyruvate (PEP)
25:14
Enzyme Pyruvate Kinase
30:36
Another High Energy Molecule: 1,3 Biphosphoglycerate
36:17
Another High Energy Molecule: Phophocreatine
39:41
Phosphoryl Group Transfers

30m 8s

Intro
0:00
Phosphoryl Group Transfer
0:27
Phosphoryl Group Transfer Overview
0:28
Example: Glutamate → Glutamine Part 1
7:11
Example: Glutamate → Glutamine Part 2
13:29
ATP Not Only Transfers Phosphoryl, But Also Pyrophosphoryl & Adenylyl Groups
17:03
Attack At The γ Phosphorous Transfers a Phosphoryl
19:02
Attack At The β Phosphorous Gives Pyrophosphoryl
22:44
Oxidation-Reduction Reactions

49m 46s

Intro
0:00
Oxidation-Reduction Reactions
1:32
Redox Reactions
1:33
Example 1: Mg + Al³⁺ → Mg²⁺ + Al
3:49
Reduction Potential Definition
10:47
Reduction Potential Example
13:38
Organic Example
22:23
Review: How To Find The Oxidation States For Carbon
24:15
Examples: Oxidation States For Carbon
27:45
Example 1: Oxidation States For Carbon
27:46
Example 2: Oxidation States For Carbon
28:36
Example 3: Oxidation States For Carbon
29:18
Example 4: Oxidation States For Carbon
29:44
Example 5: Oxidation States For Carbon
30:10
Example 6: Oxidation States For Carbon
30:40
Example 7: Oxidation States For Carbon
31:20
Example 8: Oxidation States For Carbon
32:10
Example 9: Oxidation States For Carbon
32:52
Oxidation-Reduction Reactions, cont'd
35:22
More On Reduction Potential
35:28
Lets' Start With ∆G = ∆G°' + RTlnQ
38:29
Example: Oxidation Reduction Reactions
41:42
More On Oxidation-Reduction Reactions

56m 34s

Intro
0:00
More On Oxidation-Reduction Reactions
0:10
Example 1: What If the Concentrations Are Not Standard?
0:11
Alternate Procedure That Uses The 1/2 Reactions Individually
8:57
Universal Electron Carriers in Aqueous Medium: NAD+ & NADH
15:12
The Others Are…
19:22
NAD+ & NADP Coenzymes
20:56
FMN & FAD
22:03
Nicotinamide Adenine Dinucleotide (Phosphate)
23:03
Reduction 1/2 Reactions
36:10
Ratio of NAD+ : NADH
36:52
Ratio of NADPH : NADP+
38:02
Specialized Roles of NAD+ & NADPH
38:48
Oxidoreductase Enzyme Overview
40:26
Examples of Oxidoreductase
43:32
The Flavin Nucleotides
46:46
Example Problems For Bioenergetics

42m 12s

Intro
0:00
Example 1: Calculate the ∆G°' For The Following Reaction
1:04
Example 1: Question
1:05
Example 1: Solution
2:20
Example 2: Calculate the Keq For the Following
4:20
Example 2: Question
4:21
Example 2: Solution
5:54
Example 3: Calculate the ∆G°' For The Hydrolysis of ATP At 25°C
8:52
Example 3: Question
8:53
Example 3: Solution
10:30
Example 3: Alternate Procedure
13:48
Example 4: Problems For Bioenergetics
16:46
Example 4: Questions
16:47
Example 4: Part A Solution
21:19
Example 4: Part B Solution
23:26
Example 4: Part C Solution
26:12
Example 5: Problems For Bioenergetics
29:27
Example 5: Questions
29:35
Example 5: Solution - Part 1
32:16
Example 5: Solution - Part 2
34:39
IX. Glycolysis and Gluconeogenesis
Overview of Glycolysis I

43m 32s

Intro
0:00
Overview of Glycolysis
0:48
Three Primary Paths For Glucose
1:04
Preparatory Phase of Glycolysis
4:40
Payoff Phase of Glycolysis
6:40
Glycolysis Reactions Diagram
7:58
Enzymes of Glycolysis
12:41
Glycolysis Reactions
16:02
Step 1
16:03
Step 2
18:03
Step 3
18:52
Step 4
20:08
Step 5
21:42
Step 6
22:44
Step 7
24:22
Step 8
25:11
Step 9
26:00
Step 10
26:51
Overview of Glycolysis Cont.
27:28
The Overall Reaction for Glycolysis
27:29
Recall The High-Energy Phosphorylated Compounds Discusses In The Bioenergetics Unit
33:10
What Happens To The Pyruvate That Is Formed?
37:58
Glycolysis II

1h 1m 47s

Intro
0:00
Glycolysis Step 1: The Phosphorylation of Glucose
0:27
Glycolysis Step 1: Reaction
0:28
Hexokinase
2:28
Glycolysis Step 1: Mechanism-Simple Nucleophilic Substitution
6:34
Glycolysis Step 2: Conversion of Glucose 6-Phosphate → Fructose 6-Phosphate
11:33
Glycolysis Step 2: Reaction
11:34
Glycolysis Step 2: Mechanism, Part 1
14:40
Glycolysis Step 2: Mechanism, Part 2
18:16
Glycolysis Step 2: Mechanism, Part 3
19:56
Glycolysis Step 2: Mechanism, Part 4 (Ring Closing & Dissociation)
21:54
Glycolysis Step 3: Conversion of Fructose 6-Phosphate to Fructose 1,6-Biphosphate
24:16
Glycolysis Step 3: Reaction
24:17
Glycolysis Step 3: Mechanism
26:40
Glycolysis Step 4: Cleavage of Fructose 1,6-Biphosphate
31:10
Glycolysis Step 4: Reaction
31:11
Glycolysis Step 4: Mechanism, Part 1 (Binding & Ring Opening)
35:26
Glycolysis Step 4: Mechanism, Part 2
37:40
Glycolysis Step 4: Mechanism, Part 3
39:30
Glycolysis Step 4: Mechanism, Part 4
44:00
Glycolysis Step 4: Mechanism, Part 5
46:34
Glycolysis Step 4: Mechanism, Part 6
49:00
Glycolysis Step 4: Mechanism, Part 7
50:12
Hydrolysis of The Imine
52:33
Glycolysis Step 5: Conversion of Dihydroxyaceton Phosphate to Glyceraldehyde 3-Phosphate
55:38
Glycolysis Step 5: Reaction
55:39
Breakdown and Numbering of Sugar
57:40
Glycolysis III

59m 17s

Intro
0:00
Glycolysis Step 5: Conversion of Dihydroxyaceton Phosphate to Glyceraldehyde 3-Phosphate
0:44
Glycolysis Step 5: Mechanism, Part 1
0:45
Glycolysis Step 5: Mechanism, Part 2
3:53
Glycolysis Step 6: Oxidation of Glyceraldehyde 3-Phosphate to 1,3-Biphosphoglycerate
5:14
Glycolysis Step 6: Reaction
5:15
Glycolysis Step 6: Mechanism, Part 1
8:52
Glycolysis Step 6: Mechanism, Part 2
12:58
Glycolysis Step 6: Mechanism, Part 3
14:26
Glycolysis Step 6: Mechanism, Part 4
16:23
Glycolysis Step 7: Phosphoryl Transfer From 1,3-Biphosphoglycerate to ADP to Form ATP
19:08
Glycolysis Step 7: Reaction
19:09
Substrate-Level Phosphorylation
23:18
Glycolysis Step 7: Mechanism (Nucleophilic Substitution)
26:57
Glycolysis Step 8: Conversion of 3-Phosphoglycerate to 2-Phosphoglycerate
28:44
Glycolysis Step 8: Reaction
28:45
Glycolysis Step 8: Mechanism, Part 1
30:08
Glycolysis Step 8: Mechanism, Part 2
32:24
Glycolysis Step 8: Mechanism, Part 3
34:02
Catalytic Cycle
35:42
Glycolysis Step 9: Dehydration of 2-Phosphoglycerate to Phosphoenol Pyruvate
37:20
Glycolysis Step 9: Reaction
37:21
Glycolysis Step 9: Mechanism, Part 1
40:12
Glycolysis Step 9: Mechanism, Part 2
42:01
Glycolysis Step 9: Mechanism, Part 3
43:58
Glycolysis Step 10: Transfer of a Phosphoryl Group From Phosphoenol Pyruvate To ADP To Form ATP
45:16
Glycolysis Step 10: Reaction
45:17
Substrate-Level Phosphorylation
48:32
Energy Coupling Reaction
51:24
Glycolysis Balance Sheet
54:15
Glycolysis Balance Sheet
54:16
What Happens to The 6 Carbons of Glucose?
56:22
What Happens to 2 ADP & 2 Pi?
57:04
What Happens to The 4e⁻ ?
57:15
Glycolysis IV

39m 47s

Intro
0:00
Feeder Pathways
0:42
Feeder Pathways Overview
0:43
Starch, Glycogen
2:25
Lactose
4:38
Galactose
4:58
Manose
5:22
Trehalose
5:45
Sucrose
5:56
Fructose
6:07
Fates of Pyruvate: Aerobic & Anaerobic Conditions
7:39
Aerobic Conditions & Pyruvate
7:40
Anaerobic Fates of Pyruvate
11:18
Fates of Pyruvate: Lactate Acid Fermentation
14:10
Lactate Acid Fermentation
14:11
Fates of Pyruvate: Ethanol Fermentation
19:01
Ethanol Fermentation Reaction
19:02
TPP: Thiamine Pyrophosphate (Functions and Structure)
23:10
Ethanol Fermentation Mechanism, Part 1
27:53
Ethanol Fermentation Mechanism, Part 2
29:06
Ethanol Fermentation Mechanism, Part 3
31:15
Ethanol Fermentation Mechanism, Part 4
32:44
Ethanol Fermentation Mechanism, Part 5
34:33
Ethanol Fermentation Mechanism, Part 6
35:48
Gluconeogenesis I

41m 34s

Intro
0:00
Gluconeogenesis, Part 1
1:02
Gluconeogenesis Overview
1:03
3 Glycolytic Reactions That Are Irreversible Under Physiological Conditions
2:29
Gluconeogenesis Reactions Overview
6:17
Reaction: Pyruvate to Oxaloacetate
11:07
Reaction: Oxaloacetate to Phosphoenolpyruvate (PEP)
13:29
First Pathway That Pyruvate Can Take to Become Phosphoenolpyruvate
15:24
Second Pathway That Pyruvate Can Take to Become Phosphoenolpyruvate
21:00
Transportation of Pyruvate From The Cytosol to The Mitochondria
24:15
Transportation Mechanism, Part 1
26:41
Transportation Mechanism, Part 2
30:43
Transportation Mechanism, Part 3
34:04
Transportation Mechanism, Part 4
38:14
Gluconeogenesis II

34m 18s

Intro
0:00
Oxaloacetate → Phosphoenolpyruvate (PEP)
0:35
Mitochondrial Membrane Does Not Have a Transporter for Oxaloactate
0:36
Reaction: Oxaloacetate to Phosphoenolpyruvate (PEP)
3:36
Mechanism: Oxaloacetate to Phosphoenolpyruvate (PEP)
4:48
Overall Reaction: Pyruvate to Phosphoenolpyruvate
7:01
Recall The Two Pathways That Pyruvate Can Take to Become Phosphoenolpyruvate
10:16
NADH in Gluconeogenesis
12:29
Second Pathway: Lactate → Pyruvate
18:22
Cytosolic PEP Carboxykinase, Mitochondrial PEP Carboxykinase, & Isozymes
18:23
2nd Bypass Reaction
23:04
3rd Bypass Reaction
24:01
Overall Process
25:17
Other Feeder Pathways For Gluconeogenesis
26:35
Carbon Intermediates of The Citric Acid Cycle
26:36
Amino Acids & The Gluconeogenic Pathway
29:45
Glycolysis & Gluconeogenesis Are Reciprocally Regulated
32:00
The Pentose Phosphate Pathway

42m 52s

Intro
0:00
The Pentose Phosphate Pathway Overview
0:17
The Major Fate of Glucose-6-Phosphate
0:18
The Pentose Phosphate Pathway (PPP) Overview
1:00
Oxidative Phase of The Pentose Phosphate Pathway
4:33
Oxidative Phase of The Pentose Phosphate Pathway: Reaction Overview
4:34
Ribose-5-Phosphate: Glutathione & Reductive Biosynthesis
9:02
Glucose-6-Phosphate to 6-Phosphogluconate
12:48
6-Phosphogluconate to Ribulose-5-Phosphate
15:39
Ribulose-5-Phosphate to Ribose-5-Phosphate
17:05
Non-Oxidative Phase of The Pentose Phosphate Pathway
19:55
Non-Oxidative Phase of The Pentose Phosphate Pathway: Overview
19:56
General Transketolase Reaction
29:03
Transaldolase Reaction
35:10
Final Transketolase Reaction
39:10
X. The Citric Acid Cycle (Krebs Cycle)
Citric Acid Cycle I

36m 10s

Intro
0:00
Stages of Cellular Respiration
0:23
Stages of Cellular Respiration
0:24
From Pyruvate to Acetyl-CoA
6:56
From Pyruvate to Acetyl-CoA: Pyruvate Dehydrogenase Complex
6:57
Overall Reaction
8:42
Oxidative Decarboxylation
11:54
Pyruvate Dehydrogenase (PDH) & Enzymes
15:30
Pyruvate Dehydrogenase (PDH) Requires 5 Coenzymes
17:15
Molecule of CoEnzyme A
18:52
Thioesters
20:56
Lipoic Acid
22:31
Lipoate Is Attached To a Lysine Residue On E₂
24:42
Pyruvate Dehydrogenase Complex: Reactions
26:36
E1: Reaction 1 & 2
30:38
E2: Reaction 3
31:58
E3: Reaction 4 & 5
32:44
Substrate Channeling
34:17
Citric Acid Cycle II

49m 20s

Intro
0:00
Citric Acid Cycle Reactions Overview
0:26
Citric Acid Cycle Reactions Overview: Part 1
0:27
Citric Acid Cycle Reactions Overview: Part 2
7:03
Things to Note
10:58
Citric Acid Cycle Reactions & Mechanism
13:57
Reaction 1: Formation of Citrate
13:58
Reaction 1: Mechanism
19:01
Reaction 2: Citrate to Cis Aconistate to Isocitrate
28:50
Reaction 3: Isocitrate to α-Ketoglutarate
32:35
Reaction 3: Two Isocitrate Dehydrogenase Enzymes
36:24
Reaction 3: Mechanism
37:33
Reaction 4: Oxidation of α-Ketoglutarate to Succinyl-CoA
41:38
Reaction 4: Notes
46:34
Citric Acid Cycle III

44m 11s

Intro
0:00
Citric Acid Cycle Reactions & Mechanism
0:21
Reaction 5: Succinyl-CoA to Succinate
0:24
Reaction 5: Reaction Sequence
2:35
Reaction 6: Oxidation of Succinate to Fumarate
8:28
Reaction 7: Fumarate to Malate
10:17
Reaction 8: Oxidation of L-Malate to Oxaloacetate
14:15
More On The Citric Acid Cycle
17:17
Energy from Oxidation
17:18
How Can We Transfer This NADH Into the Mitochondria
27:10
Citric Cycle is Amphibolic - Works In Both Anabolic & Catabolic Pathways
32:06
Biosynthetic Processes
34:29
Anaplerotic Reactions Overview
37:26
Anaplerotic: Reaction 1
41:42
XI. Catabolism of Fatty Acids
Fatty Acid Catabolism I

48m 11s

Intro
0:00
Introduction to Fatty Acid Catabolism
0:21
Introduction to Fatty Acid Catabolism
0:22
Vertebrate Cells Obtain Fatty Acids for Catabolism From 3 Sources
2:16
Diet: Part 1
4:00
Diet: Part 2
5:35
Diet: Part 3
6:20
Diet: Part 4
6:47
Diet: Part 5
10:18
Diet: Part 6
10:54
Diet: Part 7
12:04
Diet: Part 8
12:26
Fats Stored in Adipocytes Overview
13:54
Fats Stored in Adipocytes (Fat Cells): Part 1
16:13
Fats Stored in Adipocytes (Fat Cells): Part 2
17:16
Fats Stored in Adipocytes (Fat Cells): Part 3
19:42
Fats Stored in Adipocytes (Fat Cells): Part 4
20:52
Fats Stored in Adipocytes (Fat Cells): Part 5
22:56
Mobilization of TAGs Stored in Fat Cells
24:35
Fatty Acid Oxidation
28:29
Fatty Acid Oxidation
28:48
3 Reactions of the Carnitine Shuttle
30:42
Carnitine Shuttle & The Mitochondrial Matrix
36:25
CAT I
43:58
Carnitine Shuttle is the Rate-Limiting Steps
46:24
Fatty Acid Catabolism II

45m 58s

Intro
0:00
Fatty Acid Catabolism
0:15
Fatty Acid Oxidation Takes Place in 3 Stages
0:16
β-Oxidation
2:05
β-Oxidation Overview
2:06
Reaction 1
4:20
Reaction 2
7:35
Reaction 3
8:52
Reaction 4
10:16
β-Oxidation Reactions Discussion
11:34
Notes On β-Oxidation
15:14
Double Bond After The First Reaction
15:15
Reaction 1 is Catalyzed by 3 Isozymes of Acyl-CoA Dehydrogenase
16:04
Reaction 2 & The Addition of H₂O
18:38
After Reaction 4
19:24
Production of ATP
20:04
β-Oxidation of Unsaturated Fatty Acid
21:25
β-Oxidation of Unsaturated Fatty Acid
22:36
β-Oxidation of Mono-Unsaturates
24:49
β-Oxidation of Mono-Unsaturates: Reaction 1
24:50
β-Oxidation of Mono-Unsaturates: Reaction 2
28:43
β-Oxidation of Mono-Unsaturates: Reaction 3
30:50
β-Oxidation of Mono-Unsaturates: Reaction 4
31:06
β-Oxidation of Polyunsaturates
32:29
β-Oxidation of Polyunsaturates: Part 1
32:30
β-Oxidation of Polyunsaturates: Part 2
37:08
β-Oxidation of Polyunsaturates: Part 3
40:25
Fatty Acid Catabolism III

33m 18s

Intro
0:00
Fatty Acid Catabolism
0:43
Oxidation of Fatty Acids With an Odd Number of Carbons
0:44
β-oxidation in the Mitochondrion & Two Other Pathways
9:08
ω-oxidation
10:37
α-oxidation
17:22
Ketone Bodies
19:08
Two Fates of Acetyl-CoA Formed by β-Oxidation Overview
19:09
Ketone Bodies: Acetone
20:42
Ketone Bodies: Acetoacetate
20:57
Ketone Bodies: D-β-hydroxybutyrate
21:25
Two Fates of Acetyl-CoA Formed by β-Oxidation: Part 1
22:05
Two Fates of Acetyl-CoA Formed by β-Oxidation: Part 2
26:59
Two Fates of Acetyl-CoA Formed by β-Oxidation: Part 3
30:52
XII. Catabolism of Amino Acids and the Urea Cycle
Overview & The Aminotransferase Reaction

40m 59s

Intro
0:00
Overview of The Aminotransferase Reaction
0:25
Overview of The Aminotransferase Reaction
0:26
The Aminotransferase Reaction: Process 1
3:06
The Aminotransferase Reaction: Process 2
6:46
Alanine From Muscle Tissue
10:54
Bigger Picture of the Aminotransferase Reaction
14:52
Looking Closely at Process 1
19:04
Pyridoxal Phosphate (PLP)
24:32
Pyridoxamine Phosphate
25:29
Pyridoxine (B6)
26:38
The Function of PLP
27:12
Mechanism Examples
28:46
Reverse Reaction: Glutamate to α-Ketoglutarate
35:34
Glutamine & Alanine: The Urea Cycle I

39m 18s

Intro
0:00
Glutamine & Alanine: The Urea Cycle I
0:45
Excess Ammonia, Glutamate, and Glutamine
0:46
Glucose-Alanine Cycle
9:54
Introduction to the Urea Cycle
20:56
The Urea Cycle: Production of the Carbamoyl Phosphate
22:59
The Urea Cycle: Reaction & Mechanism Involving the Carbamoyl Phosphate Synthetase
33:36
Glutamine & Alanine: The Urea Cycle II

36m 21s

Intro
0:00
Glutamine & Alanine: The Urea Cycle II
0:14
The Urea Cycle Overview
0:34
Reaction 1: Ornithine → Citrulline
7:30
Reaction 2: Citrulline → Citrullyl-AMP
11:15
Reaction 2': Citrullyl-AMP → Argininosuccinate
15:25
Reaction 3: Argininosuccinate → Arginine
20:42
Reaction 4: Arginine → Orthinine
24:00
Links Between the Citric Acid Cycle & the Urea Cycle
27:47
Aspartate-argininosuccinate Shunt
32:36
Amino Acid Catabolism

47m 58s

Intro
0:00
Amino Acid Catabolism
0:10
Common Amino Acids and 6 Major Products
0:11
Ketogenic Amino Acid
1:52
Glucogenic Amino Acid
2:51
Amino Acid Catabolism Diagram
4:18
Cofactors That Play a Role in Amino Acid Catabolism
7:00
Biotin
8:42
Tetrahydrofolate
10:44
S-Adenosylmethionine (AdoMet)
12:46
Tetrahydrobiopterin
13:53
S-Adenosylmethionine & Tetrahydrobiopterin Molecules
14:41
Catabolism of Phenylalanine
18:30
Reaction 1: Phenylalanine to Tyrosine
18:31
Reaction 2: Tyrosine to p-Hydroxyphenylpyruvate
21:36
Reaction 3: p-Hydroxyphenylpyruvate to Homogentisate
23:50
Reaction 4: Homogentisate to Maleylacetoacetate
25:42
Reaction 5: Maleylacetoacetate to Fumarylacetoacetate
28:20
Reaction 6: Fumarylacetoacetate to Fumarate & Succinyl-CoA
29:51
Reaction 7: Fate of Fumarate & Succinyl-CoA
31:14
Phenylalanine Hydroxylase
33:33
The Phenylalanine Hydroxylase Reaction
33:34
Mixed-Function Oxidases
40:26
When Phenylalanine Hydoxylase is Defective: Phenylketonuria (PKU)
44:13
XIII. Oxidative Phosphorylation and ATP Synthesis
Oxidative Phosphorylation I

41m 11s

Intro
0:00
Oxidative Phosphorylation
0:54
Oxidative Phosphorylation Overview
0:55
Mitochondrial Electron Transport Chain Diagram
7:15
Enzyme Complex I of the Electron Transport Chain
12:27
Enzyme Complex II of the Electron Transport Chain
14:02
Enzyme Complex III of the Electron Transport Chain
14:34
Enzyme Complex IV of the Electron Transport Chain
15:30
Complexes Diagram
16:25
Complex I
18:25
Complex I Overview
18:26
What is Ubiquinone or Coenzyme Q?
20:02
Coenzyme Q Transformation
22:37
Complex I Diagram
24:47
Fe-S Proteins
26:42
Transfer of H⁺
29:42
Complex II
31:06
Succinate Dehydrogenase
31:07
Complex II Diagram & Process
32:54
Other Substrates Pass Their e⁻ to Q: Glycerol 3-Phosphate
37:31
Other Substrates Pass Their e⁻ to Q: Fatty Acyl-CoA
39:02
Oxidative Phosphorylation II

36m 27s

Intro
0:00
Complex III
0:19
Complex III Overview
0:20
Complex III: Step 1
1:56
Complex III: Step 2
6:14
Complex IV
8:42
Complex IV: Cytochrome Oxidase
8:43
Oxidative Phosphorylation, cont'd
17:18
Oxidative Phosphorylation: Summary
17:19
Equation 1
19:13
How Exergonic is the Reaction?
21:03
Potential Energy Represented by Transported H⁺
27:24
Free Energy Change for the Production of an Electrochemical Gradient Via an Ion Pump
28:48
Free Energy Change in Active Mitochondria
32:02
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Lecture Comments (4)

1 answer

Last reply by: Professor Hovasapian
Wed May 14, 2014 1:33 AM

Post by Sitora Muhamedova on May 12, 2014

love your lectures!

1 answer

Last reply by: Professor Hovasapian
Wed Sep 4, 2013 11:57 PM

Post by Donna maria on September 4, 2013

thank you for the brilliant lecture. may i ask why there were 8 L and 8 D as out of the 4 chiral carbons, i only spotted 3 that consisted of OH located to the right? Therefore, I know i have missed something important or not grasped the true concept? in my head, i see 12 to right and 4 to left?  

Monosaccharides

Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.

  • Intro 0:00
  • Monosaccharides 1:49
    • Carbohydrates Overview
    • Three Major Classes of Carbohydrates
    • Definition of Monosaccharides
  • Examples of Monosaccharides: Aldoses 7:06
    • D-Glyceraldehyde
    • D-Erythrose
    • D-Ribose
    • D-Glucose
    • Observation: Aldehyde Group
    • Observation: Carbonyl 'C'
    • Observation: D & L Naming System
  • Examples of Monosaccharides: Ketose 16:54
    • Dihydroxy Acetone
    • D-Erythrulose
    • D-Ribulose
    • D-Fructose
    • D-Glucose Comparison
    • More information of Ketoses
    • Let's Look Closer at D-Glucoses
  • Let's Look At All the D-Hexose Stereoisomers 31:22
    • D-Allose
    • D-Altrose
    • D-Glucose
    • D-Gulose
    • D-Mannose
    • D-Idose
    • D-Galactose
    • D-Talose
  • Epimer 40:05
    • Definition of Epimer
    • Example of Epimer: D-Glucose, D-Mannose, and D-Galactose
  • Hemiacetal or Hemiketal 44:36
    • Hemiacetal/Hemiketal Overview
    • Ring Formation of the α and β Configurations of D-Glucose
    • Ring Formation of the α and β Configurations of Fructose
  • Haworth Projection 1:07:34
    • Pyranose & Furanose Overview
    • Haworth Projection: Pyranoses
    • Haworth Projection: Furanose

Transcription: Monosaccharides

Hello and welcome back to Educator.com, and welcome back to Biochemistry.0000

Today, we are going to start our discussion of carbohydrates, of sugars, otherwise known as saccharides.0004

Today we are going to talk about monosaccharides- absolutely fantastic, fascinating area of biochemistry.0011

I personally, I can't decide which is more exciting.0018

I love proteins, and then when we start doing sugars, carbohydrates, I love carbohydrate chemistry, and then when we talk about lipids, when we talk about enzymes, each area is more fascinating than the next; and it is amazing when all of this starts to come together.0021

Anyway, let's just jump right on in and see what we can do.0038

I have to warn you, there are going to be lots of structures being written out.0042

And again, I don't use pictures; I like to draw everything out.0047

My recommendation, again, I can't stress it enough especially for carbohydrates, because you have lots of carbons and lots of hydroxys.0051

It's one thing to be able to look at an illustration, and by all means, you definitely want to use your book.0060

Your book has fantastic illustrations of most of these things that I'm going to be drawing, but being able to say "Yes, I can see what is going on." is very different from being able to actually produce what is going on with your hand.0065

You want to draw these things out as many as possible, and you'll discover that just by the time you draw your fifth or sixth one, you have a really, really good command of the structures.0079

So, by all means, pictures are great, illustrations are great, but you have to be able to do it with pencil and paper.0090

You have to be able to do it with your hand.0095

OK, enough said; let's jump on in, and hopefully I don't make mistakes, because again, there is lots of carbons and oxygens and hydrogens that are going be floating around.0098

OK, monosaccharides.0109

Well, let's talk about carbohydrates first in general.0110

Carbohydrates are nothing more than aldehydes and ketones with several hydroxy groups attached to the non-carbonyl carbons.0114

That is it, or carbohydrates yield these things; they yield these aldehydes and ketones upon hydrolysis.0163

Do you remember when the lesson, when we did the example problems for peptides and proteins, we talked about glucagon; and we talked about how it induces the liver to actually break up glycogen to release free glucose into the blood?0197

Well, glycogen is a carbohydrate when you hydrolyze it.0212

When the liver hydrolyzes it, it actually releases free glucose, which is the monosaccharide.0215

So, carbohydrate is just that.0222

It's either the monosaccharide itself or the aldehyde or ketone, or it produces those things when you have actually hydrolyzed it.0225

That is all a carbohydrate is.0234

It's either an aldehyde or a ketone that has a bunch of OH groups attached to the other carbons; and you'll see the structures in just a second.0235

OK, most carbohydrates have the empirical formula CH2O.0245

That's where the name comes from- carbohydrate.0266

Hydrate for the H2O, carbo for the C.0269

That's the empirical formula.0273

Now, some carbs - I'll just call them carbs - contain nitrogen, sulfur, or phosphorus.0276

OK.0287

Now, there are 3 major classes, if you want to call them that; I mean, probably not necessary, but we tend to break them up like this.0290

There are 3 major classes of carbohydrates.0299

We have the monosaccharides, which we are going to talk about today, and saccharide just means sugar, the oligosaccharides, and the polysaccharides- long words.0307

Saccharide just means sugar; mono means 1 sugar unit.0335

Oligo means a few sugar units, and poly means a whole lot of sugar units attached to each other.0338

OK, monosacchs are the simple sugars, and consist of single aldehydes and ketones with those additional hydroxy groups attached to the carbons that are non-carbonyl- OH groups.0405 OK, let's go ahead and draw some structures out; let's do some examples.0345

Examples of monosaccharides- I'm going to do a lot of these.0410

OK, there is going to be a lots of structures.0413

I want you to see them over and over again until they are just completely natural for you.0416

OK, let's go ahead and do blue, because I like blue.0422

We have examples of monosacchs, and these are going to be the, I'm going to do the aldehydes first, and they are called aldoses.0430

Aldose, D-O-S-E - that just means carbohydrate, sugar; that is the ending.0442

Glucose, mannose, galactose- they all end in O-S-E.0447

Aldose means all the sugars that are aldehydes that is a broad class.0452

Examples of monosacchs, the first one I'm going to do is one that you've already seen before.0457

It is 3 carbons; I will do the aldehyde group up here, and I think I'll put the H on...that's fine, I'll go ahead and put the H on this side: CH2OH, and I will do the OH on this side, and H.0463

This is 3 carbons; this is the diglyceraldehide.0482

You have seen this one before.0485

Remember when we were talking about protein configuration, L-glyceraldehyde and D-glyceraldehyde?0492

Remember the L-glyceraldehyde had the hydroxide on the left?0498

The D-glyceraldehyde has the hydroxide on the right.0500

That is it.0505

The glyceraldehyde, it is a 3-carbon sugar, because it has 3 carbons.0507

The carbonyl carbon is the first.0513

This is the second; this is the third.0515

Notice, hydroxy attached to the second carbon, hydroxy attached to the third carbon.0517

Also notice that his one has 4 different groups attached to it.0524

So, this carbon is actually a chiral carbon center, but we know that already because of the glyceraldehyde.0527

We have a D; we have an L.0533

Those are the enantiomers of glyceraldehyde, the D and the L.0535

OK, that is a 3-carbon sugar.0540

Well, let's go ahead and do this one.0543

Let's do C, O, H, oops let me draw the backbone first, always a good idea.0547

H2OH, do the aldehyde first; do the last one.0555

Put the H2OH on there, and now, just go ahead and attach the hydroxys.0558

An hydroxy over here, and a hydroxy over here, we will put an H.0563

We will put an H, and this is D-erythrose.0567

And again, these are just examples; you don't have to know all of these.0572

There is only a couple that you are going to have to know.0575

Well, you are certainly going to have to know the glucose, and maybe galactose and mannose, but don't worry about that.0577

I just want you to get comfortable with what's going on here and how these are drawn.0583

This is a 4-carbon sugar.0587

1, 2, 3, 4, hydroxy, hydroxy, hydroxy, attached to the non-carbonyl.0591

This is the aldehyde group, the carbon double-bonded to the oxygen, hydrogen.0598

Carbon, double-bonded oxygen, hydrogen.0603

That is it; nothing actually changes.0605

The chain just gets longer; that is all that's going on here.0607

OK, let's go ahead and do a...this is 1, 2, 3, 4, let's do a 5-carbon sugar.0610

This is going to be 1, 2, 3, 4 and 5.0620

I go ahead and put my aldehyde group up there.0625

I go ahead and put that down here, and then, I go OH, OH, and OH.0628

This is the, 1, 2, 3, 4, 5; yes, this is D-ribose.0639

This is a 5-carbon sugar.0648

OK, now, let's go ahead and do a 6-carbon sugar- probably our most important one.0654

Well, not probably- our most important one.0659

OK.0662

Actually, you know what, let me go ahead and put the Hs here.0665

And again, if you ever see a carbon that is missing a bond, the last bond is going to be an H.0669

Sometimes I forget the Hs, sometimes I don't.0676

Anyway, 1, 2, 3, 4, 5, and 6, let me put the aldehyde group up there.0680

Let me put my H2OH up here.0692

Now, glucose happens to be OH here, OH here, OH here, and OH here.0694

This is D-glucose.0703

This is a 6-carbon sugar.0709

OK, now, let's make some observations here.0713

All have aldehyde groups.0717

They are called aldoses.0731

These are all aldoses because they have the aldehyde, aldehyde, aldehyde, aldehyde.0736

Notice, the only thing that happened is the chain got longer.0744

That is that.0749

The carbonyl carbon, the carbonyl-C, is no. 1.0751

So, 1, 2, 3; this is 1, 2, 3, 4, 1, 2, 3, 4, 5 carbon.0758

This is the 1 carbon, the 2, the 3, the 4, the 5, and the 6 carbon.0767

OK, here is the important part.0774

Again, as with amino acids, the DL system applies.0778

In other words, the reference carbon, the reference C, is the chiral carbon furthest from the carbonyl carbon.0797

OK.0828

If its configuration, I should say if its configuration matches D-glyceraldehyde, then the monosacch is a D-monosaccharide.0832

It is a D-sugar; it is a D-aldose.0858

There we go.0866

So, the reference carbon in this particular case, we are going to be looking at the chiral carbon that is furthest from the carbonyl carbon, and we are going to check to see whether the hydroxide is on the right for D or on the left for L.0868

That is why if you notice, in this particular case, this right here, let's look at the D-glyceraldehyde; this is our reference molecule, so let's not worry about that.0883

This is the chiral carbon; this is our reference.0891

This configuration, if it matches this configuration, the reference carbon for the others, that is what's going to designate it as D or L.0894

In this particular case, here is our carbonyl carbon; this is chiral.0901

This is chiral; this is not chiral.0905

It has 2 of the same thing attached to it- 2 Hs attached.0907

This is not a chiral carbon.0911

So, this is our reference carbon.0913

Well, reference carbon, the hydroxide is on the right hand side.0914

It matches the hydroxy on the right hand side of D-glyceraldehyde; that is what makes it a D-erythrose.0918

If I took this OH and this H and switched positions, put the OH on the left and the H on the right, then it would be L-erythrose because it would match L-glyceraldehyde.0924

In the case of D-ribose chiral carbon, third is a chiral carbon, fourth is a chiral carbon, fifth is not, so this is our reference carbon, sure enough, hydroxys on the right.0935

Notice, on all of these, the hydroxy on the last chiral carbon, the one that is furthest away, is all on the right.0947

Glucose, second is chiral, third is chiral, fourth is chiral, the fifth is chiral, the sixth is not chiral, so this is the reference carbon.0953

The hydroxy is on the right; it makes it D-glucose.0963

If the hydroxy were on the left as written in the Fischer projection, these are still Fischer projections, it would be L-glucose.0965

Notice, these others, I can put these anywhere, and I'll get the other isomers, but we will talk about that in a minute.0973

These are just some examples.0980

What we want to realize here is again, look for the chiral carbon that is furthest from the carbonyl, that is the reference carbon.0982

The configuration at that carbon is the one you compare to glyceraldehyde to see whether it is D or L.0990

We are going to be dealing with D-sugars exclusively, physiologically- D-sugars.0999

Just like for proteins, physiologically, there were L-amino acids, but for sugars, the body uses the D-monosaccharides.1003

OK.1013

Let's go ahead and look at some other examples of monosaccharides, but this time let's do some ketoses, the ones that have ketones- draw out their structures.1016

Let's go ahead and do this in, I think I'm going to do this one in black.1026

We have examples of monosacchs, and this time, we are going to do the ketoses.1033

And again, ketose, they have a ketone group in them- all of them.1043

This is a general class.1046

Well, let's look at the 3 carbon.1049

We have 1, we have 2, we have 3, OK.1052

Because this is a ketone, the first carbon is not going to be the carbonyl carbon; it is the next one.1055

This goes here; this is going to be CH2OH, and this is going to be CH2OH.1063

This is called dihydroxyacetone.1071

The only difference between this and the glyceraldehyde is that now, the carbonyl is not on the first carbon, and the second carbon does not have the hydroxy; they have switched places.1080

The hydroxy now goes on the first carbon, and the carbonyl drops to the second carbon.1091

That is going to be the pattern of ketoses.1095

This is still labeled, though, first carbon, second carbon, third carbon.1098

Now, the carbonyl is always going to be on the second carbon of the ketose.1104

OK.1109

Let's go ahead and go back to black; let's do a 4 carbon here.1112

We have 1, 2, 3, 4; we said the carbonyl is on the second carbon, so let's put that there first.1116

Let's put RH2OH here, and there is an H2OH here.1125

Let's go ahead and stick a hydroxy on the right over there.1132

This is going to be, and let me go ahead and make sure I have my Hs.1136

These are the ones that I always tend to forget, and I also have a really, really bad habit, sometimes, of attaching an H to the carbonyl carbon.1141

Sorry, I hope you are catching those.1150

You have to be really, really careful with these structures; there is a lot floating around.1154

It is not hard; it is just detailed.1158

This is D-erythrulose.1161

And again, the carbonyl is on the second carbon, the hydroxide has gone up to the first carbon.1168

Now, this is the hydroxide; the only chiral carbon in this one is this one right here in this particular case.1174

Again, we have first, second, third, fourth; the second carbon is the carbonyl for ketoses.1180

Let's go to black; let's do the 5 carbon.1190

1, 2, 3, 4, 5, we'll put the carbonyl there.1193

We will put the H2OH here; we will put the H2OH here.1201

We want to set up our frame.1206

Now, let's go ahead and put, yes, let's leave the hydroxys on the right.1209

We have an H, and we have an H.1215

This is D-ribulose.1217

Now, know that the reference carbon is still the same.1223

The reference carbon is the chiral carbon that is furthest from the carbonyl.1225

In this particular case - I'll do this in blue - here, the reference carbon is this.1229

Hydroxy is on the right; that is what makes it D.1235

Here, this is a carbonyl; this is chiral.1238

This is also chiral; this is not chiral.1240

This is the furthest carbonyl; hydroxy is on the right.1244

That is what makes it D.1247

So, that part is still the same; you are still looking for the chiral carbon that is furthest from the carbonyl, comparing that, checking the configuration against glyceraldehyde.1248

And again, we are going to be dealing exclusively with D-sugars of the hydroxyl, and that carbon is always going to be on the right.1258

The other hydroxys, left or right, so the other ones might change.1265

OK, now, let's go ahead and do a 6 carbon.1270

Let's go back to black.1275

We have 1, 2, 3, 4, 5, 6; put the carbonyl there.1276

Put our H2OH here, H2OH on the last one.1285

Now, let's go ahead, and as it turns out, in this particular case, I'm going to go OH, OH.1290

And again, these are just examples; OH, H, H.1300

Now, you are probably wondering why it is that I put this particular OH here, and I left these.1310

Well, you remember, when I did the D-glucose, well, actually, you know what, don't worry about that.1315

Remember, we said the chiral carbons, so first of all, let's list the reference carbon.1323

That is chiral; that is chiral.1330

That is chiral; that is not chiral, so this is our reference carbon; hydroxy is on the right.1333

This is D-fructose, and again, this is the first, the second, the third, the fourth, the fifth, and the sixth.1338

Now, this one we leave alone; these 2 hydroxys, I can actually put them anywhere I want.1349

I can be left, right; this one can be left, right.1355

So, there are 4 possibilities: both left; both right; this left, this right; this right, this left.1359

And again, those sugars do exist.1366

I'm just drawing out examples for the sugars that we tend to run across the most often.1368

That is why I did D-glucose, and here, D-fructose, which is fruit sugar.1373

There is no reason why I put this hydroxy on the left and this hyrdoxy on the right other than the fact that this is the one we are going to run across most often.1381

The other sugars, the other isomers, do exist; and we will draw them out.1391

Don't worry about that, but again, these are just examples.1394

OK, now, let me go ahead and I'm going to draw out the glucose for comparison.1398

This is C, C, C, C, C, C, glucose, the aldehyde.1403

The carbonyl is on the first; let me go ahead and put this here, and we have OH, OH, OH, and OH.1411

This is D-glucose1423

You notice, the only thing that has changed is, the carbonyl has come from this carbon- red.1426

1, 2, 3, 4, 5, 6 - excuse me - the carbonyl has gone from the 1 carbon to the 2 carbon, and the hydroxy has come from this carbon up to this carbon; but notice, everything below that happens to be the same.1435

This structure is all the same; that is the only thing that makes D-fructose and D-glucose different.1461

They have different chemistry; they behave differently, but that is it.1468

That is all that's happened here.1471

On the aldoses, the no. 1 carbon is the carbonyl.1473

On the ketose, the no. 2 carbon is the carbonyl, but the numbering is still the same- this way.1476

OK, just wanted you to see what it is that actually happened here.1481

OK.1486

Let me actually write that down.1490

For ketoses, the carbonyl carbon, the carbonyl C is no. 2; and the reference carbon is still the chiral carbon, the chiral C furthest from the carbonyl.1496

That is the reference C for that one; that is the reference C for the glucose.1527

OK, I hope this is starting to make sense.1533

Again, we are just concerned with some structures here.1536

Let me go back to blue actually; there we go.1547

Let's take a closer look at D-glucose.1555

OK, let's draw the structure again: C, C, C.1564

You can never draw it enough times, trust me on this one.1567

C, C, C, 1, 2, 3, 4, 5, 6, carbonyl goes there; let me put that there.1569

Let me put H2OH here; it is right, left, right, right.1576

That is the pattern for D-glucose.1585

Once you actually draw in the carbonyl on the first carbon, then you put the hydroxy on this last carbon, the H2 which is not chiral, your pattern for the chiral carbons is right, left, right, right, so D-glucose.1586

So, D-glucose1599

And again, there are hydrogens here, but I did not put the hydrogens.1602

That is fine; I'll leave them off, but just know that there are...well, that's OK.1607

That is fine; I'll just put them in.1610

It is probably a good idea.1611

I should not leave them off.1613

OK, alright.1615

Now, notice, it has 1, 2, 3, 4 chiral centers.1617

It has 4 chiral centers, chiral carbons.1626

OK, because it has 4 chiral carbons, it has a total of 24 stereo isomers.1638

Remember what we said.1652

OK.1654

Well, let me say, in general, n chiral centers means 2n isomers- stereo isomers.1659

In other words, I have 4 chiral carbons.1684

That means I have 24, which is - 2 times 2 is 4, 8 and a 16 - I have 16 possible ways that these hydroxide, this 1, 2, 3, these 4 hydroxides can arrange themselves on these carbons.1688

This does not change; this does not change, but here, the hydroxy can be left to right, left to right, left to right, left to right, all right, all left, couple left, couple right, 1 left, 3 right, 1 right, 3 left.1704

All of those combinations contribute to the 16 isomers.1720

D-glucose happens to be one of those 16- that's it.1725

In this particular case, it is the one where you have, on the no. 2 carbon, 2, 3, 4, 5, 6, where the arrangement is the 2 carbon is on the right.1728

3 carbon is on the left; 4 carbon is on the right, and 5 carbon is on the right- that's it.1741

This is one of the 16 stereo isomers for this particular hexose.1745

OK, hexose, 6 carbons, just add that OS.1751

We also speak of pentose, tetrose, triose when we are talking about the number of carbons.1755

OK.1761

Of these 16, 8 are D-hexoses.1763

In other words, they are D in the sense that this final thing, the hydroxy, is on the right.1773

It matches D-glyceraldehyde, and 8 are L-hexoses.1779

In other words, this hydroxy on the reference carbon is on the left.1791

And again, hexose just refers to the number of carbons- that's all.1796

Hexose is just another general.1812

So, the breakdown would be something like this.1815

An aldose, that is the general, aldehyde.1820

Of the aldoses, you have the trios; you have tetrose.1824

You have a pentose; you have a hexose, 3 carbon, 4 carbon, 5 carbon, 6 carbon.1830

Of the hexoses, now, you have your D-glucose, D-mannose, you have D-allose, etc.1837

You have 8 of them, and then, you also have the L-glucose, the L-mannose, the L-allose, etc. - the other 8.1852

I hope that makes sense; what is important is number of chiral carbons.1860

Two to that number gives you how many stereo isomers there are.1865

Now, don't worry, we are actually going to draw all of these out.1869

OK, let's look at all 8 of the D-hexose stereo isomers.1873

OK.1881

Let's do this in black.1884

Let's get this again; there we go.1888

Let's look at...alright...let me see here.1892

Let's look at all the D-hexose stereo isomers.1902

If you have a 6 carbon sugar, of those 6 carbons, 4 of them are chiral centers.1919

That means we have a total of 16 stereo isomers.1924

Of that 16, half are D, half are L.1928

We are not going to be concerned about the L because physiologically D-sugars are what is important.1932

So, we are going to look at the 8 D-hexoses.1938

Alright, let's go.1940

1, 2, 3, 4, 5, 6, OK, this is an aldose.1944

I'm going to go ahead and put my H over there.1954

Now, OH, OH, OH, OH, H2OH, I'm going to leave the hydrogens off.1958

Notice, all the hydroxys are on the right.1969

The particular stereo isomer where all the hydroxys are on the right, this is called D-allose- that's it.1972

Repeat, 1, 2, 3, 4, 5, 6, put my aldehyde group up there; put that there.1984

Now, this one, I'm going to put on the left; but the others, I'm will leave on the right.1998

So, the first chiral carbon, this one, which is the carbon no. 2.2005

All I have done is I have switched the configuration on that one.2012

That gives me D-altrose.2015

OK, now, let's go 1, 2, 3, 4, 5, 6.2020

This time I think I'm just going to put my H on the right; I hope you don't mind.2028

Here, I put them on the left, on the right; it doesn't really matter because it is not chiral.2030

It does not really matter where it goes.2034

I'm going to frame it with my H2OH right there.2037

Now, I'm going to go back to the original2040

I'm going to leave the first chiral hydroxy to the left, and now, I'm going to move the second hydroxy to the left.2043

I'm sorry; I'm going to leave the first hydroxy on the right.2052

I'm going to take the second hydroxy, and move that one on the left, leaving everything else there.2055

This is our D-glucose.2060

That is the one we want: 6 carbons, 1, 2, 3, 4 chirals.2065

The pattern is right, left, right, right, right, left, right, right, as you go down.2073

That is D-glucose.2079

So, D-glucose happens to be the isomer of the 8 D-hexoses where the third carbon happens to have the hydroxy on the left.2081

The other carbons, the second, the fourth, and the fifth, the chiral carbons have the hydroxys on the right.2093

OK.2102

Now, C, C, C, C, C, C.2104

Aldehyde is here; H2OH is here.2111

Now, if I leave the first chiral and the second chiral on the right, this time, if I take the third chiral, I end up with D-glucose.2117

And again, these are all very, very different.2130

I mean, they behave the same way, but they are not the same thing- completely different molecule.2131

The configuration here is different than here.2136

OK, let's do C, C, C, C, C, C.2140

We have our aldehyde group; we have that.2156

Now, I'm going to, so here I have the first one, the second chiral, now, the third chiral.2159

Now, I'm going to go ahead and do the first 2 to the left.2169

Let me put the Hs a little bit closer, OH, but I'm going to leave this one on the right, and this one on the right.2176

This one has to stay on the right because that is the D; that is what designates the D.2185

If I were to do the L-hexoses, I would just move this hydroxide to the left because that is the reference carbon- the fifth carbon.2190

This is D-mannose.2197

Now, let's do this one, C, C, C, C, C, C, H2OH; we have our aldehyde.2203

Now, I'll do that one, and that one.2214

I'll leave that one on the right, and that one.2222

This is called D-idose.2225

OK, we are almost there.2229

Let's go, 1, 2, 3, 4, 5, 6, CH2OH; we draw our aldehyde.2236

Now, we will leave the first chiral on the right.2248

This time we will take the second and the third, and then, we will leave this one on the right.2251

This one is going to be D-galactose- also a very important sugar that tends to come up a lot.2256

And, of course, our last one, C, C, C, C, C, C, H2OH.2265

As you can see, by the time you've actually gone through these 8, you should have a pretty good command of drawing these structures; that is that one.2274

Now, we are going to have all 3 on the left.2283

That one, no, this is not going to work.2290

I need the hydroxys a little bit closer.2296

OH, OH, OH, and, of course, this one stays on the right because that is what designates it.2299

That is a reference carbon that designates it.2306

D...this is talose.2308

There you go.2314

Those are the 8 stereo isomers of hexose- that's it.2315

One of those happens to be glucose.2326

The one that has the pattern, right, left, right, right, for the hydroxys that are attached to the non-carbonyl carbon.2329

That is going to be the important sugar.2338

OK, now, some things to notice; put this in red.2341

Very, very important to notice this.2349

The no. 5 C, the no. 5 carbon, does not change configuration.2354

That one does not change configuration.2365

It is the reference carbon, and it makes these hexoses D-hexoses.2376

If I drew the hydroxy on the left, then, it would be an L-hexose.2395

It might have the same thing, except now, this one is on the left; I’d have another 8.2399

Now, let's go ahead and define something called an epimer or epimer; some people say epimer.2407

Again pronunciation, completely irrelevant.2413

Despite what some people might tell you, it is not relevant.2417

2 monosacchs that differ, if you have 2 monosaccharides that differ in the configuration around 1 carbon, those are called epimers.2421

2 monosacchs that differ in the configuration around one carbon, those are called epimers.2450

Let me give you an example of that.2456

OK, I'm going to draw glucose in the center.2460

So, let's go 1, 2, 3, 4, 5, 6, CH2OH2463

I have my aldehyde; I have my right, left, right, right patterns.2472

So, this is my D-glucose, my primary central monosaccharide.2480

Now, over here, let me go ahead and draw C, C, C, C, C, C, 1, 2, 3, 4, 5, 6, yes.2487

This is CH2OH; this is my aldehyde, and what did I use?2497

I did, oh, I did mannose.2502

OK, this is going to be left, left, right, right.2505

Notice, the only thing that I've changed is that one.2515

This one is left, left, right, right, right, right; everything is the same.2521

The only difference is, at the no. 2 carbon, these differ in configuration.2525

Here, hydroxy is on the right; here hydroxy on the left.2535

This is D-mannose, and it is called a C2-epimer of glucose, or you could say that glucose is a C2-epimer of D-mannose, or you can just say that they are C2 epimers- relative.2538

So, the only carbon that's different is the 2 carbon.2560

Now let’s do another one.2564

Let’s go 1, 2, 3, 4, 5, 6, we have that; we have that.2567

Now, what did I do?2576

I left that one over here; I think I left that one over there.2578

Oh, I changed that one and that one.2583

Now, let me go to black.2588

Now, the only difference is, this one and this, those are the same; this one and this, those are the same.2591

Ah, I changed that one on the 1, 2, 3, on the 4th carbon.2598

On glucose the hydroxy is on the right; on... is this galactose?2605

Yes, that's galactose; yes.2609

On the galactose the hydroxy is on the...this is a no. 4 carbon, so this is a C4-epimer of glucose- that's it.2613

When we talk about epimers, we just mean that, on one of those carbons, usually they will specify which carbon the configuration is reversed, is different- that's it.2627

Now, notice, this does not change the DL.2638

The DL is based on this carbon, the reference carbon.2642

Notice, hydroxy is on the right, D; hydroxy is on the right, D.2647

Hydroxy is on the right, D.2650

It is the one, the carbon that we matched against the configuration of glyceraldehyde to decide whether it is D or L.2655

OK, you are never going to find a 1, 2, 3, 4, 5, you are never going to have a C5-epimer- you're not.2660

I suppose you can talk about it, but we will never talk about a C5-epimer.2670

OK.2674

Now, let's go ahead and get to the, well, get to further elucidation of a monosaccharide structure here.2678

Let’s go ahead and go back to blue.2689

Now, oops, actually you know what, that's fine; I'll go ahead and leave it as black.2693

Now, in aqueous solution, so these monosaccharides, they are very, very soluble.2702

All these hydroxy groups, lot of hydrogen bonding, they are almost infinitely soluble.2709

I mean, you can dissolve a whole bunch, you know that already; you can dissolve a whole bunch of sugar in water, in a very little amount of water.2713

In aqueous solution, in other words, our bodies, aqueous solution, the monosacchs with greater than or equal to 4 carbons, they tend to exist in their ring formations.2720

In other words, if you were to take like D-glucose as a straight chain sugar like this, and if you were to drop this in water, one of the hydroxys and this carbonyl would actually react with each other in an intramolecular reaction; and it will for a ring.2755

In aqueous solution, most of these monosaccharides, they exist predominantly in their ring formation; and we are going to actually talk about, we are going to draw out how the ring forms in just a minute.2775

So, in aqueous solution, monosacchs with greater than or equal to 4 carbons tend to exist in their ring formations.2786

What that means is that 1 of the OH groups on the monosacch has reacted with the carbonyl carbon, has reacted with the carbonyl group, to form a hemiacetal or a hemiketal.2793

OK.2843

Now, some of you may be coming to this biochemistry course having taken only 1 term of organic chemistry; and my guess is that that particular term definitely discussed alcohols, but you may not yet have seen carbonyl chemistry.2846

The chemistry surrounding the carbon oxygen double bond, probably the most important chemistry of organic chemistry, and certainly of biochemistry, the most important functional group.2862

When an alcohol, the hydroxy group reacts with the carbonyl, it form something called a hemiacetal or hemiketal,2874

We will do the chemistry in just a minute.2884

It is not the name that I want you to know.2890

I mean, yes, it is nice to know that it is a hemiacetal or a hemiketal.2892

In other words, when one of the aldehyde, one of the aldoses reacts, you are going to get a hemiacetal.2896

When one of the ketoses reacts, you get a hemiketal.2901

It is the chemistry that I want you to understand.2905

That is what's important.2909

Let's just go ahead and make sure that that is well-understood.2910

The name itself, you might see it occasionally here and there, but it is the chemistry that's important.2915

OK, now, here is the important part.2920

OK.2926

In the process of reacting, the carbonyl carbon is converted to a chiral carbon.2928

So, the carbonyl carbon is not chiral.2953

The double bond, there is no chirality there; but when it reacts, the double bond breaks and now becomes a single bond.2955

Now, you have 4 different objects attached to that carbonyl carbon.2961

In the process of reacting, forming the hemiacetal or hemiketal, the carbonyl carbon is converted to a chiral carbon, because the COO becomes a COH.2969

It becomes an alcohol.2994

Now, it has 2 configurations available to it.3002

Now, that it is chiral, it also has 2 configurations, 2 enantiomers at that carbon, 2 configurations available.3016

We call them alpha and beta.3030

OK.3035

Now, I'll actually go ahead and leave it that way.3037

So, once it reacts, that carbonyl carbon is converted to a chiral carbon.3042

That chiral center has 2 configurations.3047

One of them, we call alpha; one of them, we call beta.3050

Now, let's go ahead and follow this very, very carefully.3052

Let's follow the formation of the 2, actually you know, I'll make sure to write everything out; I mean, I know we know what is going to happen, but OK.3056

Let's follow the ring formation of the alpha and beta configurations of D-glucose.3086

OK, let's go ahead and draw out D-glucose.3106

This is going to be...do this in blue.3110

I have got 1, 2, 3, 4, 5, 6, 2, 3, 4, 5, 6, yes, I have CH2OH.3112

I have my aldehyde group, and, of course, I have right, left, right, right.3123

OK, here is what I'm going to do, and here is how I think about it.3132

When we do the final structures, you can actually arrange it; and you can think about it anyway you want to, but here is how I think about it.3137

I take this vertical arrangement of the glucose, and what I do is rotate it 90 degrees to the right.3144

In other words, I take this molecule, and I just rotate it 90 degrees to the right; then what I do is, I've got the aldehyde on the right.3150

I have got this on the left, then I take this side of the molecule, and I go around to my left from the back, and I attack the carbonyl from the back on the right-hand side; and now, I'll show you what that looks like.3158

Let me go ahead and draw this as...actually, you know what, I'm probably going to need a little room here.3175

I'm going to go COH, and I'm going to go ahead and put the electrons there.3184

C, C, C, C, there is my carbonyl, and I'm going to go ahead and put my H down here.3190

Here, I have got OH; this is right, left.3206

That is there; this is going to be CH2OH.3218

OK, see what I've done.3225

I've rotated this to the right; I've put this carbonyl over on the right.3227

Now, I have taken this group, and I've brought it around to the back.3231

So, this part is the front; from here back, this is actually going back behind the page.3235

I have the aldehyde part, and I take this hydroxy, and I loop it around the back.3242

My carbonyl is here from your perspective.3250

The carbonyl is here, I take this OH group as on the left, and I loop it around behind, so that the hydroxy group is actually coming from behind this way because I want this oxygen on the back and on the right from your perspective.3254

OK, and here is what happens.3268

Well, these electrons, this is nucleophilic hydroxide, right?3270

These electrons, this is an electrophilic.3275

This is going to attack there, and it is going to cause those electrons to move; and it is going to go ahead and grab an H+ from solution, and turn this into a hydroxy.3279

I'm actually going to show that.3289

You know what, I'm going to do this in a different color; sorry.3293

Let me go ahead and put the electrons here.3298

Let me go ahead and do the mechanism in black.3300

These attack the carbonyl, and it goes ahead and it grabs this.3304

Now, here is what happens.3310

You are going to get 2 different structures here.3314

Now, the carbonyl carbon, this is flat.3317

If I have the C and that, this is flat; the carbonyl is flat.3322

This is the carbon, this is the double-bonded oxygen.3331

This hydroxy, you remember, the carbonyl can be attacked from 2 sides, OK.3335

It isn’t attacked that way; it's attacked from the top and from the bottom.3339

If it is attacked from the top, it is going to push the oxygen down.3343

If it is attacked from the bottom, it is going to push the oxygen up, because now, this double bond is turning into a single bond; and it is going to assume a tetrahedral arrangement.3347

It is true that we took it, and we are attacking it from this side; but what is happening is, we are actually attacking it from the top, or we are attacking it from the bottom.3362

That is what's going on.3371

So, you get 2 possible things going on.3373

This one, we will say, this is an attack from above, and this is attack from below.3377

There is attack this way, or there is attack this way.3388

OK.3391

Now, let's go ahead and draw the structures that we end up getting.3394

You end up with the following.3398

I'm going to draw these in black actually, and I'm going to write out all of my carbons because I love drawing out everything.3401

C, C, C, C, O, OH, H, this goes down.3409

This one is up; this one is down, and this is CH2OH.3421

Did I forget anything here?3428

Nope.3430

This is called the alpha-D-glucose; this is D-glucose, OK.3433

The D-glucose part is the configuration of the hydroxys.3436

The alpha part means that it is attacked from above.3442

Now, this hydroxy here is down.3445

If I'm looking at the ring this way.3450

Imagine this is flat; I'm looking at it like that.3454

If the hydroxy is below the ring, that is the alpha-D-glucose.3459

That means it was attacked from above, so it pushed that oxygen down.3462

This right here, that is the carbonyl carbon.3466

OK, this was originally the carbonyl carbon; that one right there.3471

OK, now, that is alpha-D-glucose.3474

If I have attacked from below, so that the hydroxide ends up above the ring, it is going to look like this: C, O, C, C, C, C.3480

I'll make it a little bit more uniform here.3491

C, C, C, this time, when the tetrahedral arrangement is such that this hyrdoxy is above the ring.3494

And again, notice, everything stays the same.3502

That one is down; that one is up.3504

That one is down, and this one doesn't matter.3508

This is beta-D-glucose.3512

The hydroxy is above the ring.3517

OK, hydroxy is up here.3521

Here, the hydroxy is below- that is alpha-D-glucose.3524

OK.3528

Now, here we go.3532

The carbonyl carbon, the carbonyl C, which is this one, which is now a hemiacetal, and all that means is that this was a carbonyl carbon.3537

Now, it has a hydroxy group attached to it, and it also has an oxygen connected to a carbon group.3557

OK, there is an ether function, COC, and there is an alcohol function.3566

Both oxygens are attached to this carbon.3576

That is the carbonyl carbon.3580

We draw it like this, specifically.3582

We put the carbonyl carbon on the right; we put the oxygen on the back right, and we arrange it like this, but I'll talk more about that in just a second.3583

So, the carbonyl carbon, which is now a hemiacetal - and again, hemiacetal means hydroxy group, ether group, hydroxy group, ether group attached to that - is called the anomeric carbon, and the 2 isomers namely alpha and beta.3591

It is called the anomeric carbon.3602

And, the 2 isomers namely alpha and beta, OK.3617

OK. This is the only place that the configuration is different; everything else is the same.3625

OK, down up down, down up down, nothing, nothing, up here, down here.3631

It is the only place, OK.3637

The isomers, and the 2 isomers of the anomeric C are called, well, you guessed it- anomers.3640

Alpha-D-glucose and beta-D-glucose are anomers of each other because the configuration is different only at the anomeric carbon.3657

The anomeric carbon was originally the carbonyl carbon, the aldehyde.3669

There was an intramolecular reaction.3673

So, 1, 2, 3, 4, 5, there was an intramolecular reaction of this hydroxy group attached to the no. 5 carbon that reacted with the carbonyl to form this hemiacetal.3679

Hemiacetal is a hydroxy group attached to that carbon, an ether group attached to that carbon.3691

That is what's going on here.3697

OK.3698

Now, let's go ahead and follow the same thing for fructose.3702

Yes, this one I'll do in blue.3707

I want you to see it again, that's why I'm going to go through it.3709

Let's follow the ring formation for fructose.3712

And again, fructose is a ketose.3726

Let's go ahead and draw it out.3729

Again, we have 6 carbons; we have 1, 2, 3, 4, 5, 6, but this time, we have the carbonyl here.3733

We have the H2OH here; we have the H2OH here.3746

This is there; this is there, and this is there.3752

Again, it is going to be the hydroxy on the no. 5 carbon, 1, 2, 3, 4, 5; let me number them- 1, 2, 3, 4, 5.3758

It is going to attack the carbonyl, but notice, now, we have 1, 2, 3, 4, 5 members in the ring, not 6 members in the ring because now, the carbonyl is not on this carbon, it is over here.3774

Let me go ahead and turn this around so you can see it.3789

Again, rotate it to the right.3790

Rotate the molecules to the right; take this side, and bring it around the back.3794

That is what we want to do; we always want the anomeric carbon to be over here.3800

OK, when I do that, I'm going to end up with the following.3807

Let's go, should I do this in blue?3812

Yes, let's do this in blue.3815

I have got C, C, C, C, and I've got OH, 1, 2, 3, 4; oh, yes, of course, sorry about that.3817

I have got this one over here, CH2OH, and this is my carbonyl; there we go.3838

I got lost for a second there.3843

OK, this one is up; this one is down, and this one is there.3845

Now, again, we have attacked from above, attacked from below.3855

Yes, that is fine.3861

Let me go ahead and draw the mechanism.3863

Let me put an H+ out there; this attacks the carbonyl.3867

This goes ahead and grabs that, and again, we have 2 possibilities.3871

This is attack from above.3879

OK, this is attack from below, and you end up with the following.3889

This time, for the 5-membered rings, we put the oxygen on the top; and we go C, C, C, C, C.3896

And now, if we do attack from above, that is going to push this oxygen down.3909

So, you end up with the hydroxy down here.3916

You end up with CH2OH there.3920

You end up with CH2OH here, and here, we have the OH up; and this is the OH down, and this is alpha-D-fructose, alpha, because the hydroxy is below the ring.3924

Attack from above...wait...that's from above.3944

From below, we are going to push the oxygen up.3948

We are going to end up with the following.3951

Let's go back to black here; put our oxygen there, carbon, carbon.3953

Let me number my carbons, by the way.3960

This is 1, 2, 3, 4, 5, so the hydroxy on the no. 5 carbon again.3963

OK.3972

This time from below, we are going to push the hydroxy up.3975

Let me go ahead and draw my ring first; let me close that one out.3979

This one is going to be CH2OH; this is going to be CH2OH.3982

This is going to be OH here; this is going to be OH there.3990

This is beta-D-fructose.3994

Again, arrange it horizontally, come around.4001

This is 1, 2, 3, 4, 5; the hydroxy attacks the no. 2 carbon.4006

In this particular case, this is your anomeric carbon.4015

Again, it is on your right-hand side.4018

Oxygen is on the top here, top here.4020

It gives you the beta-D-fructose, beta, because the hydroxy is above the ring.4024

When you look at this, you are looking at it like this, but really what you are looking at is - I've drawn it this way oxygen, carbon, carbon, carbon - you are looking at it that way.4029

And, we will actually do a prospective drawing in just a moment called a Haworth projection, but you are looking at it that way.4039

That is what's happening.4044

You have the hydroxy either up here or the hydroxy down here.4046

Hydroxy down here is alpha; hydroxy up here is beta.4048

OK, now, let's finish this up here.4053

So, we have got 6-membered rings.4059

6-membered rings are called...and again, you know, well, let me write down the name- pyranose.4067

One of the most frustrating things about biochemistry for me, personally, has always been the vocabulary.4080

You have got aldose; you've got hexose.4086

You have got pyranose, so 6-membered rings are called pyranose.4089

See, you have got all of these names for the same thing.4092

And again, in any conversation that you'll have with a professor or a student or something like that, anyone of those people is going to use anyone of those terms.4095

So, it is a little annoying to have to have all these terms floating around.4106

It gives the impression that you are talking about a whole bunch of different things- you are not.4110

You are talking about 1 molecule.4114

It is just, all these names that are attached to it depending on what we want to emphasize, and a lot of this is just historical garbage in the sense that this stuff has just, sort of, stayed, and we have used it, and we have used it; and now, we have this build-up of all these stuff from the history of biochemistry that we now have to synthesize, that we now have to bear on our shoulders.4118

All I can say about that is "I'm sorry"'; it is just as annoying to me as it is to anybody else.4137

I never use the word pyranose, but there it is.4142

OK, 5-membered rings, and I'll tell you in a minute why they are called pyranose and furanose.4147

5-membered rings are called furanose, and I can never remember which is which.4157

Is pyranose 6; is furanose 6?4165

Anyway, OK, now, let's talk about something called a Haworth projection.4168

Let's go ahead and do this in black.4178

Haworth projection- this is a way of looking at these sugars in 3-dimensional way.4183

We will do a Haworth projection of the pyranoses, and these are 6 carbons, yes.4192

I'm going to draw the projections, the I will draw the bases of the name pyranose.4201

OK, here is what you've got.4206

This time, I'm not going to draw out all of the individual Cs.4208

I'm going to do it in a line structure.4212

This is going to be O, boom, boom, boom, boom.4215

I want a little bit better than that.4225

OK, let's go ahead and do the alpha, OH, OH, OH, CH2OH.4241

OK, this is alpha-D-glucose.4254

Yes, it is fine; I'll just go ahead and write it- alpha-D-glucose.4261

Notice this particular projection, how we have done it.4266

Remember we said the sugar, so now, it's a ring.4268

You have go this 1, 2, 3, 4, 5, 6; the oxygen is on that side.4270

You are looking at it that way; that is what you are doing.4274

That is what this projection is.4277

The single lines, the normal lines, those are in the back; these bold lines, it comes out as a wedge, and then it stays bold like that.4280

Those are coming out towards you, and what it does is it gives you a way of seeing what is above the ring and what is below the ring.4287

Now, you remember that anytime you have a 6-membered ring, you don't have a flat ring.4294

What you have is a chair and boat confirmation.4299

Won't talk about that right now, I will in the next lesson, a little bit; but this is a really, really great projection because it shows you what is above and what is below the ring.4302

In this particular case, you have the hydroxy below the ring, so you have the alpha-isomers.4310

This is alpha-D-glucose, and notice how this is arranged.4318

The oxygen is on the top right, and the anomeric carbon is on the right.4321

This is why we said, take your molecule, rotate it to the right, make sure the anomeric carbon is right there.4327

The carbonyl, bring this side around the back, and your oxygen will actually end up staying back there.4333

That is the way you want to think about it.4338

Rotate to the right; bring it from the back, and attack above or below to create the ring.4339

OK, this is alpha-D-glucose.4346

Now, let me go ahead and do beta-D-glucose.4347

Again, we have our oxygen, we that, that, that, that.4352

I'm telling you, I don't think they will ever improve drawing these things year after year. 4367 OK, that is that, there, there, there, there.4361

Again, we've got, comes out as a wedge, bold, something like this.4374

Now, we have our beta with a hydroxy above there, and this stays.4382

This is down; this is up.4386

This is down, and this is like that.4390

This is the beta-D-glucose.4393

OK, now, some things, blue.4399

I love jumping around with these colors; it's really, really great.4407

OK, oxygen is at the back right always.4411

OK, the anomeric carbon is on the right.4425

Anomeric carbon, oxygen, anomeric on the right, oxygen, back right.4440

If you want, you can put the electrons on the oxygen, it doesn't really matter.4444

Now, here is why we call it a pyranose.4447

Yes, that is fine; I'll go ahead and do it in black.4457

Well, basically what you have is this.4463

This molecule is called pyran, and if I were to draw it in perspective, it would look like this.4470

OK, this is pyran.4479

It is based on this thing with the hydroxys attached, so they call it a pyranose- that is why.4481

That is where the name comes from.4487

I never cared for it very much, in fact I rather dislike it, but there it is.4490

OK, now, let's do our Haworth projections for the furanoses 5, yes.4496

OK, let's go back to blue, and this time we put the oxygen on the back, but the anomeric carbon is still on the right.4520

Again, we have...you know what, let me start again.4530

OK, we have got O, boom, boom, boom, boom, boom.4538

So, we have got, this comes out into a wedge, and this is a bold line here; and this comes out to a wedge, or you can just make them all bold.4545

It doesn't really matter all that much.4554

We have got an OH here; we have got CH2OH here.4557

In this particular case, that is up; that is down.4563

This is CH2OH; this is the hydroxys down below the ring, right?4570

This is this way; oxygen is back here.4574

1, 2, 3, 4, 5, we are looking at it like this.4577

The hydroxy is down below.4582

This is alpha-D-fructose.4585

I think I have got everything there, I hope, yes.4590

And, now, let's go ahead and do beta, boom, boom, boom, boom, boom.4594

And then let's go ahead and bold this out, bold this out, bold this out.4603

And now, we have the hydroxy on top, the CH2OH below.4609

This CH2OH stays.4614

This hydroxy is up; this hyrdoxy is down.4618

Is that correct?4622

Yes, that is correct.4625

So, this is beta-D-fructose.4627

A lot of structures we're drawing.4632

And, they are called furanoses because of this molecule.4634

This particular molecule is called furan.4641

They consider it a derivative of some sort, just a whole bunch of hydroxys attached to it.4649

So, that is it; that is our introduction to monosaccharides.4654

Thank you so much for joining us here at Educator.com4660

We'll see you next time for a further discussion of carbohydrates.4662

Take care, bye-bye.4665

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