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  • Intro 0:00
  • Archaebacteria 0:04
    • Thermophiles
    • Halophiles
    • Acidophiles
    • Methanogens
  • Archaea and Bacteria Compared to Eukarya 4:25
    • Archaea and Eukarya
    • Bacteria and Eukarya
  • Eubacteria 6:35
    • Nucleoid Region
    • Peptidoglycan
    • Binary Fission
    • No Membrane-Bound Organelles
  • Bacterial Shapes 10:19
    • Coccus
    • Bacillus
    • Spirillum
  • Bacterial Cell Walls 13:17
    • Gram Positive
    • Gram Negative
  • Bacterial Adaptations 16:13
    • Capsule
    • Fimbriae
    • Conjugation
    • Endospore
    • Flagella
    • Metabolism
  • Benefits of Bacteria 27:28
    • Mutualism
    • Connections to Human Life
  • Diseases Caused by Bacteria 35:05
    • STDs
    • Respiratory
    • Skin
    • Digestive Tract
    • Nervous System
    • Systemic Diseases
  • Antibiotics 40:26
    • Drugs That Block Protein Synthesis
    • Drugs That Block Cell Wall Production
    • Increased Bacterial Resistance

Transcription: Bacteria

Hi, welcome back to, this is the lesson on bacteria.0000

Of the two kingdoms of bacteria, or really the two domains, we are going to focus first on archaea.0006

In domain archaea is kingdom archaebacteria.0012

As I mentioned before in the previous lesson, archaea comes from the word archaic meaning ancient, very old.0015

This kingdom of bacteria said to resembled the earliest cells on earth.0022

We also evolved from those first cells, if you trace back animals, plants, fungi, etc..0026

We do have ancestry, dating all the way back over 3 billion years ago, supposedly.0034

Even though they are resembling the earliest cells on earth, they are still around today.0041

They have evolved as well, they are a bit different than those earliest cells on earth.0046

But that is the theory at least, that they resemble those cells the most.0050

Many of these archaebacteria are extremophiles, meaning they love extremes, extreme environmental conditions.0056

This is not true in all of them but certainly a lot of them are extremophiles.0064

Here are some examples, thermophiles love heat.0069

We are talking sometimes way hotter than boiling.0076

A classic example would be in a hot spring that is way too hot for a human to go into.0080

Or geysers, if you go to a certain National Parks, you can see geysers.0088

That water is heated deep in the crust and shooting out is very hot.0094

You will see these colors, I will show you on the next slide a really pretty image of that.0101

You can actually see some of it here.0107

This particular area has very hot water.0108

These really vibrant greens and some of these reds, that is not algae,0112

you are actually looking at billions upon billions and billions of these archaebacterial cells.0119

Halophiles, they like salty environments.0126

The dead sea, the salt lake, those are very harsh environments for most life forms.0131

Halophiles, they love the salt, they actually love to be there.0137

If you would take them out and put them in ocean water,0142

probably it would not be salty enough for them and they would not survive.0146

Acidophiles, as the name suggests, they love acidic environments.0148

Sometimes the gut of the organism will be great for that.0158

When we look at gastric juice inside of the stomach of an animal, it can be near 2 on the PH scale, it is pretty acidic.0162

Oftentimes, we are talking about even more acidic than that.0168

This kind of archaebacteria does not like alkaline or basic environments for sure.0172

Methanogens, they release methane.0178

These are still considered extremophiles because what is extreme about them is they do not like oxygen at all.0188

I will cover that later on in the lesson.0195

They are obligate anerobes.0197

You can find these in the gut of many organisms, including ourselves.0199

Just because they like extreme environments does not mean we will never be exposed to them.0204

Methanogens in the gut of an animal, they release methane.0209

What they end up doing is they take CO₂ and some other compounds.0213

When they do their own metabolic processes, a waste product they release is methane CH4.0217

That is why they are called methanogens, the fact that they generate methane.0224

Not only in the gut of organisms, you can find them in swamps, bugs, sewage treatment plants,0230

places where the air quality will not be so nice, that is methanogens.0235

They are more closely related to eukaryotes than eubacteria, archae in general.0244

I mentioned this earlier on with taxonomy and looking at those different domains, pretty interesting.0249

The fact that a bacterial cell can be closer related to our cells, when they seem so distant.0257

Here is more on the comparison of archaea to bacteria, when you look at how each of them relate to eukaryotes, in general.0266

When we compare archaea and eukarya, the archaebacteria and all eukaryotic organisms both have histones,0275

those proteins that help DNA get wrapped around it, help organize it.0284

You do not see those in bacteria.0288

You see some of the same ribosomal proteins, in terms of0291

comparing the ribosome of archaebacteria to ribosome of a plant cell, of an animal cell.0294

There is a lot in common, more so than we look at regular bacterial ribosome.0302

Similar transcription activity meaning the variety of enzymes that initiate transcription and make it happen,0308

there is a lot more in common when we look at archaea and eukarya with that.0315

Similar types of tRNA.0319

It is showing a closer evolutionary relationship, in terms of the split between archaea and eukarya.0321

We do think that that split between bacteria and archaea happened before the split between archaea and our domain.0328

When you look at bacteria and eukarya, like in terms of what we have in common with them, not nearly as much.0337

I mean we are both cells, we both have DNA, we both have ribosomes.0347

But in terms of how closely those things are, in terms of the relationship, not really.0351

This is incredible because the two groups of prokaryotes are not as closely related as we are to one of those bacterial groups.0359

Here is that picture I told you about earlier, this is from Yellowstone, this is called the castle geyser.0368

All of this yellow orange and reddishness, that is archaebacteria, specifically thermophiles that love that heat.0374

There are all kinds of pictures you can look up online with thermophiles and the brilliant colors that they produce,0384

when you find them all together with billions and billions of them.0391

The next kingdom of bacteria, I’m going to spend most of the lesson talking about eubacteria.0398

We have come across them much more often in our daily lives.0401

These are the bacteria that we are typically exposed to on a daily basis.0405

Remember EU means true, true bacteria.0410

Characteristics, these are some of the major ones that all eubacteria would have in common.0416

Nucleoid region, remember they are prokaryotic.0422

They do not have a nucleus, they do not have that membrane bound organelle that is housing the DNA.0425

This is known as the nucleoid which means it is not really a nucleus.0430

You got that usually a singular chromosome there in the middle region.0435

Peptidoglycan cell wall that, I will underline here in green for you, it is the part that is in yellow here.0440

Peptidoglycan, this is amino acids that link polysaccharides.0450

That name make sense because peptido tells you protein like peptide bonds, polypeptide.0459

Glycans sounds like glycolysis, glycogen, part protein, part sugar, that is making up that cell wall.0465

That is a very common cell wall compound that you would see with bacteria.0474

In archaebacteria, you do not typically see a peptidoglycan.0480

They have other compounds in their cell walls.0484

Binary fission, this is how they divide.0487

It is like bacterial mitosis but we do not call it mitosis because0498

mitosis is those different phases with how the chromosomes look and what the chromosomes are doing.0502

Since eukaryotes like animals and plants have numerous chromosomes to keep track of,0511

you have to have that system to make sure it works out correctly with splitting the DNA.0516

With bacteria, typically there is that one circular chromosome in the nucleoid.0521

It happens much faster, it is a simple process, you do not see prophase, metaphase, anaphase.0526

Sometimes it happens in as short as 20 minutes time.0532

And then, no membrane bound organelle, that is generally true.0536

You do not see mitochondria, chloroplast, ER, golgi, lysosome, etc..0541

I will give you one exception, when you look at cyanobacteria, these used to be called,0548

not anymore because it is a misnomer or misnaming, blue green algae.0563

We do not call them blue green algae anymore because they are not protist,0576

they are not eukaryotes which is what algae are.0579

Cyanobacteria is the proper name now.0583

Cyanobacteria, they do photosynthesis as a bacterial cell.0587

They do not have chloroplast but you do see thylakoid membranes inside.0590

They are not going to do photosynthesis as efficiently as plant cells in chloroplast.0601

You can occasionally find membranes inside of bacterial cells.0607

It is not as common, in general we say prokaryotes do not have membrane bound organelles.0613

When we look at eubacteria, in general, there are three classic bacterial shapes.0621

The first one is coccus, this is singular, plural is cocci.0626

Here we have one coccus, one spherical cell, diplococci, there are two.0635

Streptococci, when they are in a line like this, together attached that can cause strep throat.0642

Strep throat is a terrible throat infection, if you ever had it, it feels like there are knives in your throat.0650

You can blame this infecting your pharynx, your throat region.0657

Staphylococcus or also called staphylococci is a bundle.0662

This is where the word staph infection comes from.0667

When we have strep throat with that line, staph infection it is a bundle, almost looks like a bundle of grapes.0670

A staph infection definitely more deadly, in general.0678

When staph gets in your body, it is something that you really need antibiotics for.0683

You are going to take antibiotics for strep throat as well.0687

More people die of staph infections than this other one.0690

Looking at it, it looks a bit more intimidating, that bundle of them.0695

If these divide and get through parts of the body, they can cause us some problems.0699

These are less common, in terms of the naming.0705

Other names for different arrangements of these cocci cells.0708

Streptococcus, I do not want you to think that the streptococci only cause strep throat.0715

These can also cause skin infections, I will mention some of those later on in the lesson.0720

Bacillus also known as, in plural you would say bacilli.0727

It is that just I in place of the US.0735

These are rod shaped bacteria.0737

Here is an image here in this micrograph.0740

If you look carefully could see they all look longer like that.0742

Each of these is a rod shaped cell.0749

They can get together just like these up here, you can have staphilobacillus.0752

You can have streptobacillus or streptobacilli.0757

That is also another way they can be arranged.0761

Finally, spirillum, I also heard the terms spirochete.0764

This is more common, spirillum, spirilli would be the plural.0768

They are spiral, you can see that they kind of look like that.0778

One of the more common ones you may have heard of that is this shape is syphilis,0786

that sexually transmitted disease is a spirillum, in terms of the shape of those bacterial cells.0791

Next bacterial cell walls, when we look at this cell wall and the layers, there are two main varieties.0799

Bacteria either gram positive or gram negative.0805

This is named after a scientist Hans Christian Gram, who discovered this difference when he was staining bacteria,0809

so you could see them more easily under a microscope.0816

He notice that, certain bacteria kept a certain color and it would not wash off.0819

The other kind, the color would not stick to them.0823

Gram positive bacteria have a plasma brain with a peptidoglycan wall outside of it, that is normal.0827

I actually showed you an image of that earlier.0836

I’m going to underline that in purple.0839

Here we have the plasma membrane.0841

This would be a rod shaped bacterium.0845

On the outside of it, here is that peptidoglycan.0850

This is if you took a cross section through the bacterium.0859

You can see that, that is just kind of the traditional look, a lot of bacteria is gram positive,0862

having a plasma membrane inside with a superficial outer peptidoglycan cell wall.0867

It ends up staining purple.0874

All these purple cocci cells, those are gram positive cocci bacteria.0875

Some of them, you can see it is forming that staphylococcus look.0883

There is actually a substance called crystal violet,0888

that is the classic kind of a purple dye that if you put on these cells, it will stay there.0898

It would not wash off with alcohol rinses.0903

It sticks to that peptidoglycan substance.0906

However, you have gram negative which is pink.0909

These bacteria have a peptidoglycan layer that normal cell wall component, sandwiched between two plasma membrane.0915

There is this extra phospholipid layer on the outside.0922

These cells have that, first plasma membrane.0927

Outside of that, here is that sandwich.0937

Here you have that look that gives you that structure, that gives you that outer lipidy layer that will not hang onto the purple dye.0944

When we put crystal violet on it, it will not last with the different rinses and it looks pink.0953

You can see if you look carefully, you have got rod shaped bacilli bacteria that are gram negative, in this particular micrograph image.0959

Bacterial adaptations, here is the first set of them.0975

First, a capsule, it is one of those first images I showed you the term capsule was in that diagram.0978

I did not talk about it at that time because not all bacteria make capsules, but some of them do.0986

This can be a very good adaptation.0992

It is an extra layer that some bacteria can secrete outside of their cell wall.0994

It helps them stick to surfaces and better withstand attack from organisms that want to consume them or antibodies or even antibiotics.0998

This is a little different in gram negative.1010

Gram negative on the previous slide, had that layer outside of the peptidoglycan but this is a little bit different.1012

Here is a bacterial cell, the capsule, let us do it in green.1021

They have secreted this as the sticky substance outside of all their cell wall.1032

It helps them actually, sometimes stick to the surfaces that they are on, whatever substrate they are feeding off of wherever they exist.1039

Also, it is sometimes harder for antibodies which have this Y shape to actually get to the protein sticking out of the surface of the bacteria1047

to incapacitate them and make them a target for white blood cells that can eat them up.1059

A capsule is a good adaptation that some bacteria can actually use.1066

Fimbriae, this is a plural term for briae, each one of these is fimbria.1071

They look like, almost like little ropes coming out of the bacterium.1076

They are hair like bristles that allow bacteria to better attach themselves to neighboring cells.1080

Similar to what a capsule can do, in terms of like sticking to something.1085

These are really effective, it is like you would tie in ropes to the surface around you, so that someone cannot pick you up.1090

The ropes are tied and keeping you attached.1098

This can make bacteria very hard to get rid of, when they are attached to the area that they are on.1103

Bacterial adaptations, this is another one.1111

Conjugation, here we are not talking about conjugating verbs like you would see in a language class, this is a bit different.1114

Bacteria can copy and change circular pieces of DNA called plasmids, and transmit them to neighboring cells via pilli.1121

The singular term is pillus, and that is what this is.1129

It basically is a cytoplasmic bridge, these are cytoplasmic bridges.1133

Cytoplasmic bridges, that is what this is.1147

It is reaching out, trying to find a recipient.1148

Here is the donor, there is that DNA in the nucleoid region.1151

This is a plasmid, we are calling it the F plasmid.1157

There are genes that allows some kind of adaptation, some kind of ability that this bacteria can pass on to all its buddies in the area.1161

This could allow antibiotic resistance, passing that along will transform all the others around it so they can resist the antibiotic.1171

Maybe it allows them to divide more quickly, maybe gives them the ability to make a capsule,1179

or gives them the ability to have some other kind of adaptation.1184

In an earlier lesson, I gave the example of, this kind of like a utility belt that can make Bruce Wayne into Batman.1187

You do not need plasmids to survive as a bacterium, it is not going to have genes that are crucial for life.1197

But it will have genes that can certainly help and improve on your state of being, as a bacterium.1203

This particular cell, this donor cell, will connect its pillus to another one.1211

And now they are connected, their cytoplasm regions can actually be exchanged.1217

They will settle up next to one another.1224

This particular donor will use DNA polymerase to make a copy of its plasmid and send it on along.1226

And then finally, when you are done, this particular recipient can now be a donor of this plasmid to some other cell.1233

These are identical copies, they should be, if DNA polymerase did its job.1241

This can actually form a pillus, sometimes they are called a sex pillus because in a sense,1246

this copying and exchanging of genetic material is the closest bacteria it can have to sex.1253

The closest they can come to having sex because they do asexual reproduction.1259

This pillus, they can make contact with another bacterium and pass it on.1266

In the matter of, I would say a few days, you can have this particular plasma ending up in millions upon millions of bacteria.1271

It is a great adaptation, it is something that animals cannot do with each other.1281

Bacteria certainly have an advantage in this respect.1287

Bacterial adaptations number 3, and endospore.1291

Here is a bacterium with its chromosome, I will give it ribosomes.1294

This is not an endospore yet, this is the active bacterium, it is in favorable environmental conditions,1308

it is just hanging out doing its thing.1316

Under harmful environmental conditions, a bacterium can shed most of its cell and shield its DNA in a protective coat.1318

In this becomes an endospore, I’m just giving you one little shape.1327

It will just be that, it will actually shed typically most of its ribosomes, its cell wall, the majority of that.1336

It will just shield the DNA and it could shield some other parts.1344

Allowing them to have this little shape like that, there are a few varieties of endospores.1349

When their conditions become favorable again, it has the DNA it needs to get back to this state.1353

It can remake ribosomes, it can rebuild itself.1361

The beauty of this endospore is you can have bacteria with the endospore making ability,1364

survive freezing, survive boiling, survive conditions where there is no moisture at all.1371

One example would be anthrax, the full name is anthrasis bacillus, that is one of the main ones of anthrax.1379

When people are exposed to it, this would be an example of bioterrorism exposing someone to anthrax, it is deadly.1391

It looks like a powder, it is completely dried, that is the endospore form.1400

All it takes is exposure to mucous membranes, just inhaling a little bit of it, it just comes back to its kind of normal metabolic state.1405

It goes from endospore back into this and they will actively divide,1414

spread through your respiratory tract and cause fatality if it is not treated soon enough.1418

Endospores great for bacteria, sometimes bad for us.1424

Flagella, they are not just a bacteria adaptation.1429

You see flagella in animal cells, plant cells, even fungal cells, and certainly in protists.1433

Flagellum in bacteria like always, they allow locomotion.1440

Motility is another word for that.1445

Motility is different than mobility because motility is when a living being is moving itself.1448

Being motile, that is certainly an advantage for bacteria because they can escape organisms that want to eat them.1456

Moving is a great adaptation in general, for any organism.1464

Flagella, it is a good thing.1468

Sometimes bacteria have multiple flagella, not just one flagellum.1471

Metabolism, in terms of what they need gas wise, to actually process nutrients and get energy.1476

A few varieties, obligate aerobes, this means they need O2, like we do.1485

A lot of bacteria are obligated to do aerobic respiration.1495

They need to get oxygen to break down compounds and get enough ATP.1501

Especially, bacterial infections in the lungs, you would expect that they are obligate aerobes1508

because your lungs have oxygen going in them, plenty.1513

If they need O₂, it is a good place they can be.1519

Something like tuberculosis, TB, would be and obligate aerobe.1522

Facultative anerobes, this is like the best of both worlds.1526

They can have O₂ or no O₂, they can deal with either.1530

That is a great, the fact that like, if oxygen is around, they will use it and they will get ATP out of it.1536

If there is no oxygen, it is alright, they will still survive.1543

Whereas an obligate aerobe, needs O₂.1547

Facultative anerobes, it is alright, it can deal with it either way.1551

That is a great adaptation for them, having that ability to deal with either.1556

And then obligate anerobes, O₂ is toxic to them.1563

They do not like oxygen, exposed to enough of it, and they will not live.1572

A good example would be tetanus, tetanus is an obligate anerobe, so is botulism, the botulism bacterium.1578

Tetanus, most commonly you will hear about people stepping on a rusty nail, an old nail,1588

that nail punctures deep into, let us say the foot.1595

Deep where you are not going to get significant oxygen exposure in that particular part.1598

That bacterium will kind of hide in that deep area under tissue.1604

The crazy thing is tetanus can cause death, if not dealt with antibiotics.1609

The amazing thing is the bacterium does not have to move around body1616

because if it gets in the bloodstream, there is enough oxygen there where it is not going to be able to deal with it.1618

What does get around the body is the toxin.1624

There is a toxin that the tetanus bacterium will produce and that ends up affecting your muscles negatively,1627

causing lockjaw, causing a tensing of muscles to the point where you cannot even breathe anymore.1633

With bacteria that are obligate anerobes, they cannot deal with the O₂.1642

Benefits of bacteria, they are not all bad.1649

Here are some mutualism examples.1652

You will hear more about this with the ecology lessons.1654

Mutualism is a symbiotic relationship in which both species benefit.1656

They are both scratching each other back, they are both helping each other out, it is a good thing.1661

Intestinal flora that release vitamins K and B12.1666

You will get bacteria in the guts of animals where the bacteria benefit because1669

they have got a food source there, certainly, and they got protection.1677

They are sheltered in the intestine, good for them.1681

What they are providing to the animal is these vitamins that otherwise, they maybe not getting enough of them in their diet.1684

The bacteria are cranking them out and giving them these vitamins that are good for just the health of the animal.1691

That is I will scratch your back, you scratch my back, kind of example.1698

Nitrogen fixation in root nodules of plants, some plants really depend on bacteria to get fertilizer, in a sense.1702

There are these bacteria in soil that will get nitrogen out of the atmosphere, fix into their cells,1711

kind of like carbon fixation in photosynthesis.1717

They get nitrogen out of the air, that is coming into the little holes in the soil through the different dirt particles.1720

They get the nitrogen into the root of the plant.1729

Being associated with them, root nodules of plants, the bacteria have a safe home.1733

They get benefit from there.1738

The plant gets nitrogenous compounds, that in a sense are fertilizers.1741

That is a nice association there.1744

The digestion of cellulose in ruminants.1747

Cellulose is the main component of plants cell walls.1749

Cellulose, this polysaccharide is not digestible for most animals on their own, including you and I,1760

we cannot break down cellulose in our gut.1768

It is fiber, it is good for our diet but we do not get a significant amount of energy from here.1771

We are not actually breaking apart the bonds between the glucose in there and absorbing glucose.1776

It just runs through us.1782

But in ruminants, in a lot of hooved animals, hooved mammals, that do what is called ruminant digestion,1785

when we look at horses, cows, deer, etc., they will eat plant material all day long.1791

They will be munching on grass, hay, leaves, etc.1799

The bacteria in their gut that has a nice home, the bacteria get good out of that.1802

The bacteria will actually, because of their ability, break down the cellulose into individual sugars that they can then get energy out of.1809

That is brilliant that, that exists for a lot of animals.1818

Here you see plenty of bacterial cells.1823

You could see these are gram negative.1827

These are actually a kind of intestinal bacteria that, if your natural intestinal flora were not present,1830

for some reason they declined, in terms of the population inside of your gut,1840

bacteria like these can spread and causes intestinal infection.1846

Having your bodily flora is very important.1853

Speaking of which, more connections to human life in terms of the benefit.1855

Bodily flora, what this is referring to is all the bacteria on your skin, in your mouth, every orifice of your body, inside your body.1859

I have heard theories, I do not know if they had been mathematically substantiated.1868

I have theories that there are more bacterial cells on you and in you, than the amount of cells that is you,1873

which is crazy to think about that there could be that many cells on you and in you, that technically are not you.1881

The reason why that is conceivable is when you compare the size of a bacterium to the size of like one eukaryotic cell,1887

like let us say one of your skin cells.1894

If this is one of your skin cells, you can have bacteria that are much smaller.1897

Tons of them is just hanging on the surface of one skin cell.1906

You can have lots of bacteria on you.1914

That is not a bad thing, obviously we want to take showers and use sanitary things and such.1915

Having your bodily flora is good because if you wipe off too many of them,1924

let us say you are over using hand sanitizers or washing your hands obsessively, taking three showers.1928

The more you strip off your bodily flora that you would used to, your immune system can deal with,1933

it is all good that you are used to each other.1939

The more you strip them off, the more you are leaving bare territory for foreign bacteria from other people,1942

from other things you have touched, to get on your skin to propagate, to divide.1948

And those can make you sick, if it is introduced inside your body, if you get a cut or you swallow them.1952

Ironically, people who wash their hands too much are more likely to get sick.1959

If you have a friend who is obsessed about that, you might want to give a little knowledge about that.1966

Food, we all love it, we need it.1972

A few things that bacteria help process, chocolate.1977

When we look at cocoa beans or cacao, depending on who you ask.1981

The beans where chocolate comes from, very hard shell.1987

There is a process I have heard of where you can use a certain kind of bacteria to dissolve that hard shell.1991

It makes a lot easier in the process of making chocolate.1997

Cheese, a lot of cheeses is not just mold that is used to process and make cheese from milk, cream, etc.2001

It is actually bacteria, there are different strains bacteria that you can use to make, let us say cheddar, for instance.2009

The difference between medium and sharp cheddar,2016

sharp cheddar, the bacteria worked for longer on it and made it more acidic, after more time went by.2018

If you have ever compared medium cheddar cheese to sharp cheddar cheese or extra sharp,2025

it tastes more tangy, a little bit more acidic.2030

That is because the bacteria worked on a bit more, in terms of what they were spitting out into the cheese.2034

Yogurt, lactobacillus is what you are seeing right here.2040

You should try this, if you have access to a microscope.2046

I’m sure you can see this on the internet with videos.2049

If you have access to a microscope, you put a drop of yogurt, it has live active cultures in it,2053

on a slide and look in it, you will see plenty of bacteria, lactobacillus.2059

This actually can help with digestion, it is a good thing.2065

Medicines, in the previous lesson I bought up how you can take advantage of bacteria to crank out medicines for us.2070

Insulin is one of the examples, we have used bacterial processes,2078

the fact that we can introduce genes to the bacteria and get them to soak up the gene and express it.2082

They will crank out proteins that are compatible with us, human proteins from human genes.2087

That is a great thing that bacteria can do.2094

Also, I have read about bacteria being used to clean up oil spills.2096

It is amazing, what you can get bacteria to do.2102

Here are some diseases caused by bacteria.2106

I'm only going to cover one of them in each category.2109

This is not all of them, this is just scratching surface.2111

Sexually transmitted diseases from bacteria, syphilis, gonorrhea, and Chlamydia.2116

There are antibiotic that can be used to treat these, they are curable.2120

Syphilis, you are looking at it, this is a spirilli, spirillum cells.2124

This is something that can be transmitted to the body via sexual contact and it is treatable.2132

Years ago before it was treatable, it would spread throughout the body to different regions and2137

end being something called tertiary syphilis like third stage syphilis.2142

We would get like this swelling regions where the syphilis would have inhabit parts of the head.2146

That was a sign that you are at the later stage of infection and close to death, if you have tertiary syphilis.2155

Now, you do not see this much because it is treatable.2160

Respiratory infections, strep throat from streptococcus, tuberculosis, pneumonia.2164

Tuberculosis, I will spell it out for you, also known as the red death.2171

This something where you can be exposed to tuberculosis but not actually get the infection.2183

There is that little test that doctors or nurses will do with that forearm test.2188

They inject something into your forearm, that bump, if it goes away, it means you have not been exposed to tuberculosis.2192

If the bump stays, it means tuberculosis has been exposed to your body.2201

It does not mean that it successfully inhabited your lungs, and made these tubercules, these harmful colonies.2205

They will do a chest x-ray to verify do you have the tuberculosis infection in your lungs.2213

These little colonies, these casings of bacteria develop that eventually burst and cause bleeding and coughing up of blood.2219

It is quite contagious, people with tuberculosis need to be quarantined and treated so not spreading it to other people.2228

With skin diseases, impetigo, acne, leprosy, carbuncles.2236

Leprosy, it is not just a disease you hear about from the bible.2242

You do not see these does much in first world countries, developed countries, these days.2246

Leprosy is a bacterial disease that irritates your skin.2250

Acne, not just from bacteria but bacteria can make acne more of a problem.2255

There are genetic links and hormonal things that contribute to getting acne for certain people.2261

Impetigo, this is spreadable from person to person via skin contact.2268

You see it a lot with kids playing on the playground, it forms little sores on the skin.2273

Digestive tract, gastroenteritis, food poisoning, dysentery, cholera, peptic ulcers.2280

On the right down here, this is the cholera bacteria.2285

Cholera is a deadly disease, it makes you have diarrhea and vomiting so intense that you are losing way too much fluid,2288

because of what the bacteria does to your intestines.2298

Losing so much food to the point where you can die from that fluid loss, if untreated.2301

Nervous system, botulism from clostridium botulinum.2307

I already talked about tetanus earlier.2312

Meningitis, bactromeningitis, that infects the meninges around your brain and spinal cord.2313

The infection of that membrane can cause death, if untreated.2326

When you think about the brain and spinal cord, the bone which is not going to budge right next to it,2332

if you get inflammation of that membrane because of the infection of bacteria,2338

eventually it will put so much pressure on the brain, spinal cord, that can cause permanent damage, if untreated.2343

Systemic diseases, these are diseases that end up having effects on multiple tissues.2349

Bubonic plague actually came from fleas that were on rats.2355

And of course, the black death was the biggest incident of this, killed lots of people in Europe, hundreds of years ago.2363

You still see it today, I heard a story recently in the news about a girl who was playing in the forest,2372

she put her coat or jacket down on the ground, it turns out there is a dead squirrel right there.2378

The jacket was on the squirrel for while, potentially fleas or bacteria that was on the squirrel got on the jacket.2383

Something on the jacket got into the girl and she had this bubonic infection.2392

She did recover because they caught it in time.2397

It is not just an ancient disease, it still is around.2400

Typhoid fever, you can get typhoid from exposure from fecal matter, from water or food.2404

That is why it is important that people who handle your food that they wash their hands thoroughly, after using the bathroom.2411

Diphtheria ends up being a throat infection that can cause complications and death, if untreated.2416

Antibiotics, this is a key to kicking bacteria butt.2428

These are drugs prescribed to treat bacterial infection.2432

There are two types, in terms of what they are targeting when they are actually put inside the body.2434

There are antibiotics that block protein synthesis.2440

There are antibiotics that block cell wall production.2444

The protein synthesis, if you have bacteria that no longer can actually make use of their RNA,2446

in terms of proteins that they are producing, they are not going to survive long in the body.2454

You have got tetracycline, this is one of these that actually will block protein synthesis.2459

I think amoxicillin is another one.2466

Those that block cell wall production, antibiotics like penicillin does that.2468

Cell wall production, if they can actually do binary fission and make new cell wall parts to actually do that,2476

they are not going to be able to spread and be effective in causing the illness that the antibiotic is used to treat.2486

Two approaches to defeating bacteria in the human body.2492

Increased bacterial resistance has been occurring gradually.2497

This is an example bacterial evolution.2500

Since bacteria divided at much quicker rate than generations of animals or plants,2503

you can see evolutionary steps happen much faster in bacteria.2511

Here are some examples, penicillin resistance.2515

Penicillin, back in the day was a very common antibiotic to destroying bacteria in human bodies.2517

Penicillin comes from a mold penicillium, that particular substance that the mold secretes inhibits bacterial growth.2524

When it was first used on patients, only about 3% of bacteria that penicillin was used to target or resistant,2534

meaning penicillin is ineffective.2541

But it would get rid of 97% of those infections.2544

Today, about 90% of bacteria are resistant to penicillin.2548

The more you expose bacterial populations to antibiotics, you are giving them fuel to develop some kind of mutation against that.2554

Overuse of antibiotics can be a problem.2562

MERSA, this is used to stand for Methycillin resistant staphylococcus areus.2564

This is a kind of bacteria, staphylococcus areus, methycillin resistant means that that particular bacteria, a few decades ago,2587

when you actually put methycillin into the infection in that person's body, it would not die.2598

Resistant to methycillin, give amoxicillin to the patient, give other kinds of antibiotics.2604

But today, the name has been adjusted now to a more proper name is multiple resistance.2611

Because now, these staph infections known as the MERSA, there is a lot of antibiotics that it is resistant to.2625

Unfortunately, you see MERSA infections most commonly in hospitals.2631

Why is that, you go to a hospital to get better but people who come to the hospital who were sick,2636

people come to the hospital with this.2642

It ends up in the hospital room.2644

They will clean the room , they will clean the various things the person is exposing themselves to.2647

It is hard to completely get rid of MERSA.2654

Most of the cases are actually contracted in hospitals.2657

If it is not treated with the appropriate antibiotics quickly, it can cause death.2661

Hand sanitizer, you know how companies that make hand sanitize, it says it kills 99.9% of bacteria.2666

Part of the reason why they are saying 99.9% is so that they do not get sued,2676

if you actually get sick after using their product.2680

Some of it is a legal loophole but their main legitimate claim that 0.1% or less, the hand sanitizer will not destroy.2684

They already have a resistance to it.2695

If you keep using hand sanitizer over and over,2697

you are giving those bacterial populations more exposure to something that they could eventually get used to.2702

They could potentially develop a mutation in the plasma that resists it.2709

They can pass it along to their buddies via conjugation.2714

And then, you got a case where hand sanitizers were ineffective.2717

Overuse of this, overuse of antibiotics can be a dangerous thing.2721

Last thing before we end, if you are wondering what is going on here,2724

this is actually a white blood cell engulfing MERSA bacteria.2728

Some people will get exposed to this bacteria but their white blood cells just kicks its butt and it does not cause problems.2733

You could see that this was part of staph, staphylococcus.2740

Coccus is spherical shape, staph is a bundle.2745

It is eating bits of that bundle.2748

But other people exposed to MERSA, they need those special antibiotics and2752

they need them fast to beat that resistant bacteria.2755

Thank you for watching