Enter your Sign on user name and password.

Forgot password?
Sign In | Subscribe
Start learning today, and be successful in your academic & professional career. Start Today!
Use Chrome browser to play professor video
Raffi Hovasapian

Raffi Hovasapian

ATP & Other High-Energy Compounds

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
Loading...
This is a quick preview of the lesson. For full access, please Log In or Sign up.
For more information, please see full course syllabus of Biochemistry
  • Discussion

  • Download Lecture Slides

  • Table of Contents

  • Transcription

  • Related Books & Services

Lecture Comments (12)

1 answer

Last reply by: Professor Hovasapian
Sat Sep 16, 2017 8:12 AM

Post by Swati Sharma on September 16, 2017

isn't  negative 30.5 greater than negative 61.9 on the number line scale. So why do you keep saying that the latter is greater than the former when it s the other way around ?

1 answer

Last reply by: Professor Hovasapian
Fri Jan 13, 2017 7:26 PM

Post by Amer Reda on December 12, 2016

Hi, thanks for the amazing lecture. I have one question:
At 37:30 of the video, what's the difference between 1,3-biphospgoglycerate and 1,3-bisphosphoglycerate ?

1 answer

Last reply by: Professor Hovasapian
Sun Jul 3, 2016 7:56 PM

Post by Kaye Lim on June 16, 2016

-After being introduced to the coupling between endogenic and exogenic rxn, I kind of look at a random rxn between 2 reactants forming 2 products and asking myself if the reaction that I see is also coupled rxn as well in which to make deltaG of the rxn itself as a whole is thermodynamically favorable. My questions are:

-Is all or the majority of rxns in which deltaG is negative (not only biological rxns)are coupled rxn?

-If so, do I analyze the structure of reactants and the products to know which species went from high Energy to a lower Energy and which did the opposite to figure out if the rxn belongs to the coupled rxn theme?

-Does High Energy molecule have higher Energy stored in its bonds compared to low Energy molecule?

1 answer

Last reply by: Professor Hovasapian
Sun Jul 3, 2016 7:49 PM

Post by Kaye Lim on June 15, 2016

At 29:20, would you please explain again how Tautomerization drives the rxn forward?

So the major product form is the Keto form which drive the rxn into making more of the enol form which also ends up turning into the stable keto form?

-For high Energy molecules, what make them high in Energy if the Energy in the bond is not that high as you said? Also does high Energy molecules mean these molecules are unstable and more reactive?

1 answer

Last reply by: Professor Hovasapian
Fri Feb 20, 2015 10:05 PM

Post by bea v on February 18, 2015

Wow! The ATP explanation is excellent. Thank you.

1 answer

Last reply by: Professor Hovasapian
Sat Sep 20, 2014 7:57 PM

Post by shafaq ahmad on September 18, 2014

Hi,
Why ATP hydrolysis is exothermic but have high activation energy?

ATP & Other High-Energy Compounds

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
  • ATP & Other High-Energy Compounds 0:10
    • Endergonic Reaction Coupled With Exergonic Reaction
    • Major Theme In Metabolism
  • Why the ∆G°' for ATP Hydrolysis is Large & Negative 12:24
    • ∆G°' for ATP Hydrolysis
    • Reason 1: Electrostatic Repulsion
    • Reason 2: Pi & Resonance Forms
    • Reason 3: Concentrations of ADP & Pi
  • ATP & Other High-Energy Compounds Cont'd 18:48
    • More On ∆G°' & Hydrolysis
    • Other Compounds That Have Large Negative ∆G°' of Hydrolysis: Phosphoenol Pyruvate (PEP)
    • Enzyme Pyruvate Kinase
    • Another High Energy Molecule: 1,3 Biphosphoglycerate
    • Another High Energy Molecule: Phophocreatine

Transcription: ATP & Other High-Energy Compounds

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

Today, we are going to continue our discussion and talk about ATP and other high-energy compounds.0004

Let's just go ahead and jump right on in.0009

Now, we saw previously that an endergonic reaction can actually be coupled with an exergonic reaction to run the endergonic reaction under circumstances where it would not, otherwise, go.0013

Let's start with that; we saw that the endergonic reaction...let's call it no. 1.0027

Glucose + inorganic phosphate goes to glucose 6-phosphate + H2O.0042

So, the δG for this one was +13.8kJ/mol.0051

OK, we saw that it could be coupled to the exergonic reaction.0061

We will call it reaction no. 2, which is the hydrolysis of the adenosine triphosphate.0078

ATP + H2O goes to ADP + inorganic phosphate, and the δG for this particular reaction ended up being very, very large, negative, so -30.5kJ/mol.0085

OK, we saw that they could be coupled to accomplish the result of the endergonic reaction but via a different pathway.0103

We saw glucose + PI goes to G6P + H2O; and over here, we have the ATP.0136

We have the H2O, and then, of course, we have the ADP and the PI.0147

Similar species, they cancel, and what you get is a net reaction.0155

We have Glc + ATP going to G6P + ADP; and the δG for this, which is just the sum of the δGs of the previous reactions, we ended up with -16.7 - and sorry about that, did not give myself enough room - kJ/mol.0160

We saw that we could do that, an endergonic reaction, so we achieved the same purpose.0183

Our purpose was to take glucose and to convert it to glucose 6-phosphate.0188

Well, that is the same thing here; we want that reaction to take place, but we just gave it a different pathway by coupling it with a reaction that has enough energy to give away, to actually turn an endergonic reaction into an exergonic reaction.0192

This is a very, very, very important theme, and this is exactly what adenosine triphosphate does.0206

Well, it is almost all of it it does; let's go ahead and take a look at this just a little bit more clearly.0215

I am going to go ahead and draw a structural representation of this.0221

Let's go ahead and do a glucose molecule here.0226

Let's see; well, you know what, let me give myself a little bit more room.0231

I will draw it down here.0238

OH, CH2, we have the OH; and let me go ahead and draw my phosphate over here.0242

O, P, double bond O, (O-)-, OH, and let me go ahead and fill in the rest of my glucose so that we do not forget.0252

The normal endergonic reaction wants to happen as that and that ultimately, but hydroxide is not a very good leaving group, so this reaction is not very likely.0263

By providing an alternate pathway for this thing to take place, here is what happens.0279

Let me redraw the glucose; we have this, this.0287

We have CH2; I will put a little line there.0295

And now, we have O, P, O, P, O, P, O; and we have the ribose, and I will just go ahead and put the adenine here.0299

That is that, double bond, double bond, double bond.0314

I know writing these things out can be a bit tedious, but that is life.0318

OK, let me finish this, or I should say that is biochem.0323

Alright, this, that way, this goes that way; this is a very likely reaction.0330

This is highly likely and highly thermodynamically favorable- that is it.0338

That is all that is going on here.0344

Neither reaction 1 nor reaction 2 takes place.0348

In other words, we talk about using the energy from the hydrolysis of ATP to run an endergonic reaction, but ATP is not actually being hydrolyzed.0352

In other words, water is not coming and splitting ATP releasing an inorganic phosphate; and then that inorganic phosphate is reacting with the glucose- that is not what is happening.0364

Those reactions, they are separate; but when we couple them together via a different pathway, the same result is achieved.0374

So, when we talk about driving a reaction via ATP hydrolysis, the hydrolysis is not actually taking place; and I think it is very, very unfortunate that biochemistry still uses that kind of language, but as long as you remember that it is just a terminology, it is not actually taking place, the reaction is going via a different mechanism- this is what is happening.0385

This is going to be direct phosphorylation of this glucose substrate via ATP.0406

There is no free phosphate floating around that is going to react with the glucose.0412

OK, now, this is a major theme - the major theme - in metabolism, which we are going to be getting into very, very soon, using the energy of incoming nutrient molecules - in other words, the food that we ingest, the carbohydrates, the proteins and the fats - using the energy of incoming nutrient molecules to create the ATP, which will then drive, otherwise, endergonic reactions in the creation of the molecules the body needs.0418

That is it; that is all that is happening with metabolism.0505

You take in food, carbohydrates, proteins, lipids.0510

the breakdown of those foods, the catabolism, takes the energy from those foods and uses that energy, and it stores it in adenosine triphosphate.0517

The body creates adenosine triphosphate molecules, and it sends those adenosine triphosphate molecules out.0527

And now, it can use that energy to drive these endergonic reactions, which are necessary to create order in the body.0534

It needs nucleic acids; it has to form proteins.0543

It has to form carbohydrate polymers; it has to pump solutes across membranes.0546

It has to do all sorts of things, so we could take the energy from the nutrient molecules, put it into ATP.0551

ATP goes and does what it does- the anabolic process.0558

you have the catabolic process - the breakdown - converge into ATP.0562

ATP starts the anabolic process, building the molecules that it needs.0566

Let's go ahead and actually draw this out.0571

OK, I think I can do it on this page right here; let me go ahead and draw one little arrow going down like this.0575

And, I will say "carbs, fats, proteins"; and this is going to be catabolic.0584

Actually, you know what, I am not going to write that just yet.0599

OK, and our depleted products are going to be CO2; I am going to have H2O, NH3.0603

Then, let's go ahead and draw a little circle like this.0613

We have adenosine phosphate + inorganic phosphate, and we have adenosine triphosphate.0618

Now, let me go ahead and draw another arrow; this time, I will make it go up, ATP.0623

OK, now, we have amino acids.0632

We have the sugar monomers.0640

OK, we have our basic fatty acids, and we have nitrogenous bases; and we are going to form our proteins, our polysacchs.0650

We are going to form our lipids; we are going to form our nucleic acids.0673

And then, of course, there is transport; there is mechanical work, osmotic work- whatever it is that we need that energy for.0681

We take in our nutrients.0691

The catabolic pathways of the body break things down.0695

They spit out the energy depleted products.0700

The energy that they take from these carbs, fats and proteins, they use it to take adenosine diphosphate + inorganic phosphate to create ATP.0704

Now, ATP can be used to drive the anabolic pathways.0712

Anabolic means the creation, to actually make the proteins, the polysacchs, the lipids, the nucleic acids, that the body needs in addition to all of the other energy needs- that is it.0718

That is all that is going on; this is metabolism.0727

Catabolism, anabolism- together, they are your metabolism.0731

That is all that is happening, ATP, as the primary energy intermediary in this whole process- that is it.0735

OK, now let's take a look at why ATP serves the function that it serves.0745

Let's see; let’s see the why.0753

Let's see why the δG of ATP - or ATP hydrolysis, I should say - is large and negative.0762

Well, let's go ahead and draw this out.0785

Let's draw out the 0, P, 0, P, 0, P, not zero - O.0789

Sorry about that; I am thinking about mathematics here.0797

Ribose and we have adenosine.0803

It will take me just another second here to finish this molecule; OK, now, we have an H2O molecule.0808

The hydrolysis, when this takes place, we end up with H, O, P, O-, O- plus our ADP, which is O, P, O, P, O.0814

And we have ribose, and we have adenosine.0838

Sorry about all these; this is just the nature of biochemistry, with these big molecules.0844

OK, the hydrolysis of adenosine triphosphate releases an inorganic phosphate and it release ADP, so this is ATP.0848

Now, why is it that the δG for this reaction is really, really large and negative?0860

Well, here is why; the first reason is...I will do this in blue.0865

Take a look at all the negative charges here- negative, negative, negative, negative.0870

Negative charges or positive charges, all the charges, they do not like being close together; there is going to be repulsion.0875

So, if some process can come along and relieve some of that electrostatic repulsion, it is going to happen really, really easily.0881

In other words, this step of the water coming in and kicking this off, it can actually remove 2 negative charges and move them far away from the rest of the molecule.0888

That is a stabilizing force; because of that stabilizing force, it tends to push the energy down.0897

That is why you get that nice -δG.0903

One of the things that contributes to the negative, large δG is relief of the electrostatic repulsion among the negative charges.0906

OK, the second reason.0930

Well, you notice that one of the products that is formed is the inorganic phosphate.0934

The inorganic phosphate has several - it has 4, actually - resonance structures.0939

And anytime you can form a product that is resonance stabilized, that is going to pull the reaction forward.0951

It wants to be stabilized; it wants to be low energy.0960

The inorganic phosphate, one of the products of the hydrolysis, has several resonance forms; so, its formation is highly favored.0963

And the resonance forms, let me go ahead and draw them out just so you see them.0982

Let me go ahead and draw it out this way, so P, boom, boom, boom, boom.0987

I will go ahead and do that, O, P, O, O.0995

Let me go ahead and just put that one there; I will put the double bond there, so that.1002

Let's move the double bond around in a circle here so, O, P.1006

I should have made it a little smaller; that is OK.1012

It is not a problem, O, O, and this time I will put the double bond here.1013

We will put the negative charges here, and we have one more resonance contributor.1019

It is going to be O, P, O, O, O over here; and we will do that, something like this.1024

And, of course, we have our H+.1033

These 4 resonance structures, really, really, really drive this reaction forward.1036

Inorganic phosphate wants to be formed, and it will take every opportunity that it can in the easiest possible way.1041

This contributes to the stability, to the -δG, of this reaction.1048

OK, our third thing.1053

Well, the concentrations of the adenosine diphosphate and inorganic phosphate in cells is far less than their equilibrium values.1056

In the actual cell, the concentration of the ADP and the PI, the products, is a lot less than the equilibrium values would be.1088

That is going to pull the reaction forward by Le Chatelier's principle and their equilibrium values.1099

Mass action favors the forward reaction; excuse me.1110

And, I do not need to write the reaction over again.1125

OK, now, let's see; let me go back to red here.1128

Now, even though the δG for this is -30.5, again, this does not mean that the hydrolysis reaction just happens.1135

In other words, the ATP + H2O goes to ADP + PI.1163

Yes, it has a really, really large - δG; but that does not mean the reaction just happens anytime that ATP is in the presence of water.1167

OK, remember, δG is a measure of the tendency of a reaction to happen, the degree to which it wants to happen, not the fact that it actually does happen.1176

Circumstances have to be right in order for it to happen.1186

ATP is actually kinetically stable.1190

Remember, we talked about kinetic stability?1198

It has a high activation energy, so just because thermodynamically it is favorable, kinetically it is stable.1200

A lot has to happen for this thing to actually take place.1205

It is kinetically stable and requires an enzyme for an appreciable rate of hydrolysis.1209

And let me go ahead and draw this out in terms of an energy diagram for you; so we have something like this.1233

Even though the δG is really, really negative...you know what, let me make a little bit more room here.1241

I do not want to write over the words; let's go ahead and do it like let's say that.1248

This is our energy; this is our reaction coordinate.1254

We have that; we have that.1257

OK, δG is negative, but look at our activation energy.1261

Our activation energy is very, very high for ATP; and this is going to be the ADP + PI + water.1265

The hydrolysis of ATP has a very high activation energy, which means that it is kinetically stable.1278

Now, of course, we want it to be kinetically stable; we do not just want anytime adenosine triphosphate happens to be in the vicinity of some water, that it is just going to split up.1283

We do not want it to do that; we want adenosine triphosphate to be available, so that it can actually couple with endergonic reactions.1292

If anytime it is in the vicinity of water, if it just hydrolyzes and releases that heat into the surroundings, well, that is not going to do anything.1301

The body, the cells- these things are isothermal systems, so the transfer of heat, yes it will produce heat, but heat cannot do any work in an isothermal system.1310

In other words, there is no temperature differential from inside the cell to outside the cell.1319

They are at the same temperature so heat cannot flow; the only time heat, itself, can do work is when heat flows.1324

But, I mean yes, it can get hot; but no work can actually be done.1331

We want the ATP to be available to couple with other reactions.1337

We do not want it to just hydrolyze, to produce ATP; that does not do anything for us.1342

It is thermodynamically favorable, and it uses that favorability when it couples with other reactions.1348

It is kinetically staple, so ATP in the cell stays ATP.1354

There is a whole bunch of water around as you know, but it does not hydrolyze; it requires an enzyme to hydrolyze.1358

Only if it needs to hydrolyze, then it will do so; this is profoundly important.1363

OK, let's see, a little bit more information.1370

The δG of ATP hydrolysis - as we keep reiterating - is -30.5kJ/mol.1376

Now, and again, this is based on the transformed biochemical standard - 1M concentration for aqueous species, 1atm for gaseous species and so on - but concentrations in cells are not standard.1386

The result is that actual δG values for ATP hydrolysis are from about -50 all that way to, maybe, -65kJ/mol.1418

Under standard conditions, -30.5kJ/mol, that is a lot; but under cellular conditions, it is actually better.1450

-5 to -65- that is fantastic; it is such a huge amount of free energy that the body can use per mole of ATP to do what it needs to do.1457

Now, for our problems, of course, we are just going to be using standard values because again, it is a standard.1469

It is something that we can always count on; we are going to be using the -30.5, but know that in cellular conditions, it is actually better than that.1474

OK, now that we have talked about ATP, let me go ahead and switch to black here.1482

Now, let's take a look at some other compounds that have high -δGs of hydrolysis.1489

ATP is not the only one; ATP is the primary one.1498

It is the one that all of the metabolic processes use, but there are other phosphorylated compounds that also have high δGs of hydrolysis.1502

Let's take a look at some of those.1512

Let's now look at other compounds - this gives us a chance to take a look at some other molecules, take a look at some other themes, that is it, that is all that is going on here - that have large -δGs of hydrolysis.1516

OK, the first one we are going to look at is something called phosphoenolpyruvate.1549

I think I am going to do this on another page, though; I need a little bit more room than what is available here.1553

The first one is - let's do it in blue - phosphoenolpyruvate.1560

Now, you are going to see it as one word; I tend to not like writing long single words, so I just write it as two words.1576

I do not think it really matters all that much; if you have a teacher that is really specific about it, you can write it as a single word, but just know that you will see it both ways.1583

Phosphoenolpyruvate and it is abbreviated as PEP- very, very important molecule.1590

Here is what happens; let's see.1596

How should I draw this?1600

That is OK; I will go ahead and draw it like this.1602

A little bit of C, let's do this C; this is CH2.1606

Let's go O, P.1616

So, this is phosphoenolpyruvate; this is our PEP.1621

Now, it is going to undergo the following transformation, and we are talking about hydrolysis.1626

Water comes in, splits off this phosphate.1635

Water is in; inorganic phosphate is out, and what you are left with is the following molecule.1642

O-, I have got C; I have got a double bond.1649

I have got my C; I have got my CH2, and I have got my OH.1652

You know what, I am going to write these later in red.1660

Let me just draw out the structures here.1665

Now, this...OK, and what takes place here is tautomerization.1669

You remember from organic chemistry- tautomerization.1677

A double bond switches places when a hydrogen moves, so what you end up with is the following.1682

O-, C, double bond, C, this is going to be CH3; and this is going to be O.1687

Now, let me go to red; this is our phosphoenolpyruvate.1697

In the process of hyrdolyzing and breaking off this inorganic phosphate, what you end up creating is this pyruvate molecule; but this is the enol form- enol, meaning it is an alkene and an alcohol.1701

Well, what happens is something called tautomerization, so this molecule is actually more stable in the keto from.1717

Just think of it as this H basically moving over here and this double bond moving over here.1725

The mechanism will not concern us right now, but that is what happens.1730

You have this molecule, the keto form of the pyruvate; and tautomerization really, really stabilizes a molecule.1735

It really wants to be this, but the fact that it tautomerizes and becomes this more stable, drives the reaction forward.1746

And because it pulls the reaction forward, it has a very large -δG.1754

So, this is another force; tautomerization is another driving force for large -δG.1759

Keto form, enol form and this is the pyruvate.1765

OK, let me go ahead and write this out in shortened notation.1777

What we have is PEP 3- + H2O goes to pyruvate plus - it is going to be pyruvate minus actually - inorganic phosphate, which is 2-.1781

Let's make sure the charge is balanced; yes, yes, we do.1800

2-, minus, and this is 3-; I think I wrote 3 but it is not really very clear, so how is that?1803

Now, this has a huge, huge -δG.1808

It is -61.9kJ/mol.1814

That is fantastic; that is virtually twice the hydrolysis δG of adenosine triphosphate, which is big in and of itself.1820

This is a very, very high energy phosphorylated molecule.1827

OK, now, let's see.1832

OK, notice how large the δG is.1839

Notice how large it is, virtually twice that of ATP.1849

Now, notice something else; notice the inorganic phosphate as one of the products.1854

You should start to think about the coupling of reactions.1865

If something is a product, you should think to yourself "well, wait a minute, do I have a reaction where this particular product happens to be a reactant, and if so, can I actually couple those reactions to run a particular reaction?".1870

Well, let's see.1882

The question is: Is it possible to use all this energy - this is a lot of energy, we do not want to waste it - to somehow make adenosine triphosphate?1886

Because the hydrolysis δG of ATP is -30.5, but the hydrolysis δG of the phosphoenolpyruvate is -62, so it has more energy.1906

It can actually drive the reverse reaction of ATP hydrolysis.1920

It can take adenosine diphosphate, combine it with the inorganic phosphate and actually create ATP instead of using it up; that is extraordinary.1924

We want to see if the following i possible; is it possible to use all this energy to somehow make ATP?1933

Can we do this; can we couple this reaction: ADP + PI goes to ATP + H2O?1940

Now, notice, I have reversed the reaction, so the δG for this is going to be a +30.5kJ/mol.1951

And can I combine it with the hydrolysis of the phosphoenolpyruvate, which goes to...I will just write Pyr + inorganic phosphate.1960

Well, let's see; we have that and that cancel.1972

We have H2O, and H2O cancel.1974

So, theoretically, we can take phosphoenolpyruvate, combine it with ATP - I am sorry, ADP, adenosine diphosphate - and it will transfer its phosphoryl group to the adenosine diphosphate to form adenosine triphosphate + pyruvate.1977

And, well, the answer to this question is yes; you can actually do this, and the δG for this is going to end up being -31.4kJ/mol.2000

Now, the enzyme that accomplishes this - I should not say "accomplishes this" - that facilitates this is pyruvate kinase - and do not worry, we will be talking about that later on when we talk about glycolysis, so we will definitely be revisiting this reaction - and this happens to be the final step of glycolysis.2016

This happens to be the final step of glycolysis - woo, all these long words - and here is the best part.2051

This reaction is a testament.2067

These are the kinds of things that completely, completely amaze me to this day.2073

I think that it is fantastic that the body has come up with these amazing things to save energy to be efficient- absolutely extraordinary.2078

This happens to be the final step of glycolysis and is a testament to the body's efficiency in taking this opportunity to remake ATP that was used up earlier in the glycolytic pathway and not just waste all this free energy.2088

It is fantastic; this reaction is going to end up taking place.2158

It might as well couple it with something, and in the process, let's go ahead and actually form some ATP that we ended up using up earlier in the process- recycling.2162

This is absolutely fantastic; this is really, really beautiful.2173

OK, let's talk about another molecule here; this time, let's just write another high-energy molecule.2177

Now, when we say high-energy molecule, we are not talking about the energy in the bonds.2190

The energy in the bonds, themselves, is actually not that high; when we talk about high-energy, we are talking about the amount of free energy.2195

We are talking about the δG, that it has this much free energy to give up.2205

That is what we mean when we say high-energy molecule.2209

OK, this time we are going to do 1,3-biphosphoglycerate.2214

OK, again, the hydrolysis of 1,3-biphosphoglycerate, this is another phosphorylated compound, that when I hydrolyze it, it has a large -δG.2228

Let's go ahead and draw this out.2239

We have C, C, and C.2243

Let's see; we have O.2249

We have P; this is there.2252

This is there; this is there.2253

Let's go ahead and put the Hs here, CH2, CH2.2256

We have O, P here, O-, O-.2260

OK, this is the no. 1 carbon; this is the no. 2 carbon.2265

This is the no. 3 carbon, so we have 1,3-biphosphoglycerate; so there are 2 phosphoryl groups on here.2271

Now, the reaction of this one, what happens here is H2O comes in as the other reactant.2276

And, of course, it spits out one of the PIs, and what you end up with is the following: C, C, C.2286

Let's put H2 here, H2 here; this is going to be O-.2296

This is going to be O, and this is P; I have switched the double bond here.2302

Here, I put it on the right; here, it does not really matter.2307

Again, resonance forms there, so it is not a big deal; this is the 1,3-biphosphoglycerate.2312

And here, we have the 3-phosphoglycerate.2319

Let's write the reaction; this is going to be 1,3-BPG, 4- + H2O, the actual equation.2330

We have 3-phosphoglycerate plus a PI, which is 2-.2340

This is actually 3- - 1, 2, 3, 1, 2, 3, 4, yes, everything is good - plus an H+.2346

What actually happens here is you form the 3-phospohglyceric acid.2352

The protonation, there is an H right here, but then it deprotonates; so it becomes a 3-phosphoglycerate.2357

All the charges balance here and the δG for this particular reaction, again, very, very huge- -49.3kJ/mol.2362

OK, and let's go ahead and close off our discussion with just one more high-energy molecule.2373

This is going to be phosphocreatine.2383

You know what, I think I am going to do this one in blue just for a change of pace.2391

OK, we have phosphocreatine, and let's see.2396

How shall we draw this one?2404

Yes, that is fine; we can draw it from here.2407

OK, this is P; and let's go ahead and do that.2410

Let's go ahead and put those on there; let's go ahead and put the NH.2415

And then we have the C, and then we have another N; and we have a CH3.2420

Let's do CH2 and CO...you know what, I think I am just going to write this as COO-.2430

That is the carboxyl group there, then, of course, we have the nitrogen here with a positive charge.2437

So, this is phosphocreatine, and it is going to undergo...you know what, I should probably have made that smaller, but that is OK.2444

Let's go ahead and do that; here we go.2453

Again, water comes in; we are talking about hydrolysis.2458

The inorganic phosphate leaves the reaction, and what you end up with is the following: H2N.2460

This is C, NH2; we have another N.2468

We have CH2; we have COO-, and we have another CH3.2475

OK, this is phosphocreatine; let me do this in red.2481

This is phosphocreatine, and this right here is creatine.2487

I will write it on top because I am actually going to write some resonance structures here.2493

It might be nice if I actually wrote the words; how is that?2498

You get so into it; OK, that is creatine.2503

Let me go back to blue; let me put my positive charge here.2506

So, you notice you have a nitrogen that is protonated; there is 4 bonds on it, so it is carrying a formal charge of that.2509

Well, notice you have a carbon; you have a nitrogen here.2514

You have a nitrogen here, and you have a nitrogen here.2518

Basically, what can happen is this thing has resonance structures; this double bond can actually move around because of that resonance stabilization that is provided by creatine.2521

The phosphocreatine is a highly thermal dynamically favorable reaction, that it wants to give up that phosphoryl.2531

It wants to give up this phosphoryl group; it wants to transfer it to someplace else in order to form creatine, which has this resonance stabilization, which really, really drops the energy very low to give us a very large δG negative.2540

Let me go ahead and draw the resonance structures in here.2557

Let's go ahead and put the double bond on this side.2562

H2N, we will go ahead and put that there, C, NH2, N, CH2, COO-; and we have CH3.2566

So, we will put the positive charge on that one, and then we have one more resonance structure; and it is going to be right there.2577

Let's go H2N, single bond carbon; let's go NH2, right there.2586

Let's go double bond on the N there; we have our CH3 group.2593

We have our CH2, and we have our COO-.2599

These 3 resonance structures, the positive charge is shared among the 3 nitrogens- high degree of stability.2604

Anytime you have resonance structures in a product, it is going to be a very stable molecule.2611

That stability is what pulls the reaction forward and drops the energy content of the product that gives you the high -δG.2617

Let's see here; for creatine, we have a resonance stabilization.2628

It just means the 3 nitrogen share the positive charge.2644

And notice, in this particular case, the P, the phosphoryl group is attached to a nitrogen not an oxygen.2655

So, it can do that; that is not a problem.2660

And so, this is the bond that we are breaking between the nitrogen and the phosphorus.2663

OK, thank you for joining us here at Educator.com2668

We will see you next time, bye-bye.2671

Educator®

Please sign in for full access to this lesson.

Sign-InORCreate Account

Enter your Sign-on user name and password.

Forgot password?

Start Learning Now

Our free lessons will get you started (Adobe Flash® required).
Get immediate access to our entire library.

Sign up for Educator.com

Membership Overview

  • Unlimited access to our entire library of courses.
  • Search and jump to exactly what you want to learn.
  • *Ask questions and get answers from the community and our teachers!
  • Practice questions with step-by-step solutions.
  • Download lesson files for programming and software training practice.
  • Track your course viewing progress.
  • Download lecture slides for taking notes.