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00:02 Okay, testing testing. Alright Welcome. Uh let's see what we

00:13 here. Alright, so oh it's be that, hold on, let

00:20 something. There we go. almost. Hey, there we

00:45 Okay, so few announcements so of I think we all know that I'm

00:52 activate this. Uh Okay so announcements of course today is and so hopefully

01:14 look at the material beforehand, watch video, right? Uh and you're

01:18 on it, We'll find out and same thing, we'll do the same

01:23 on Tuesday Part two. Okay, um weekly quiz one that starts

01:34 it's gonna be open monday through friday monday. Okay, It'll cover the

01:41 one stealth. You covered this weekend and whatever we talked about in chapter

01:47 today. Okay. Um if you in lab lab, don't be confused

01:55 the lab quiz is today thursday through lecture quiz, friday through monday,

02:02 ? So don't get those two things . Okay, um Smart work.

02:08 the first smart work assignments due Uh Okay, so as we go

02:14 today um if if you are not well on these questions, number

02:22 all the questions gonna be posted after . Okay. Um there's like 12

02:28 , 12 quicker questions. Okay. your score is not super fantastic,

02:33 wouldn't jump off a cliff but I be concerned. Okay. Um you

02:40 , if you think you need maybe it's flexible on your own whatever

02:44 just uh if you get like I know 40% of the points or whatever

02:50 should go, hmm maybe I need do something here. Okay at least

02:56 assess yourself activist. Okay so um the other thing is uh ticker ticker

03:05 County day of course academic. What's about? What's that to do with

03:09 ? Because if you're free you're absolutely to to collaborate consult um on these

03:17 . That's fine. Okay but you take a session I. D.

03:22 you see there. 8945 91 and to your neighbors outside. Okay.

03:30 is an absolute violation of academic You will the hammer will come down

03:34 and all those getting the, getting session I. D. And I

03:39 find these things out. There are logs and things I can look at

03:42 reduce this. So don't do Why would you wanna help somebody who's

03:45 even here? Crazy. Alright so don't risk. Okay so um alright

03:55 do have to finish up a little of chapter one very short but we

04:00 going to start with, I remember last time we talked about the before

04:05 after question. Okay um and so did that before. I'm just pulling

04:10 the data from last time. So look at that same question again.

04:18 and that's this. Alright saw this . Let's see we had 22 people

04:30 it correctly last time. 100 Okay so let's see there any

04:48 Looking for the true statement if there one Okay. Timer's on winding down

05:21 . 87654 21. Okay. Well had 22 answered correctly the first time

05:41 more added to that total. So it's G it is jeep

05:50 None of these are true germ theory fermentation doesn't does not that doesn't explain

05:55 disease. That's coach postulates uh ecologically you are a consumer not a producer

06:04 . Aren't you carry? Uh Some diseases may be caused by more than

06:09 microbe, correct? But a single can only cause one disease incorrect.

06:17 . Um The example there was streptococcus cause strep throat or the fever.

06:25 . Handwashing with soap is not this and sepsis or more correctly. Probably

06:33 they call um What's the term? There's another term I think of it

06:41 it's not disinfection. Disinfection is inanimate , right? Not living tissue.

06:47 so vaccines work by stimulating your body produce antibodies. Not answer any questions

06:55 All right. Alright. So the bit we gotta do is on

07:01 I'm just going to mention a couple things. I'm not gonna go into

07:05 here but um I'm sure you're all that I hope we are the

07:10 Right, bacteria have been around particular has been around longer than anything else

07:17 this planet. Right. Nearly four billion with a B years.

07:21 Uh There's evidence to support this of from microfossils um And other types of

07:28 molecules I'll mention here in a Um I mean in terms of a

07:33 timeline of life, right? So are going to be somewhere uh away

07:38 the and here. Okay, so course we haven't been around as long

07:43 maybe our revolution has been going on maybe six million years, I think

07:48 began evolving so from our previous Um but you know, highlights here

07:54 terms of this group, right? terms of uh cyanobacteria, that until

08:00 this was strictly anaerobic from this period this period here. Anaerobic, no

08:08 , no atmosphere. Okay, even before. Right, so up

08:14 that point and then stole the option in the atmosphere into the environment,

08:19 ? Not overnight. Of course they get to 21% 02, but over

08:24 , several hundreds of thousands of But instrumental because that then evolved a

08:32 to metabolize using oxygen. How we , right, it's the most energy

08:36 type of metabolism is aerobic metabolism. so being able to do that,

08:41 led the way for having to produce organism right from bigger eukaryotic cells to

08:49 cida types and so forth. the introduction of 02 in the atmosphere

08:53 huge. Not just from that but from creating an atmosphere,

08:59 Um the ozone layer, right? shielding shielding earth from harmful UV life

09:04 to life involved in water as kind protection away from these harsh conditions but

09:10 um creating an atmosphere allowing that and life to come onto land and all

09:17 that that led to so very Okay so um so in terms of

09:24 mentioned microfossils as evidence you can see between organisms, Microbes in these fossils

09:33 modern day type hop Androids are a actually chapter three thing. Um They're

09:41 to cholesterol in our membranes, Has had a similar function of components

09:48 help stabilize membranes but they are a you can actually find and it's been

09:54 in the fossil record and are only precarious. This is evidence of how

10:00 they are. Okay, so uh so in this early earth environment,

10:08 know what kind of materials are evolving when we talk about those little sort

10:12 types before. Right, They use materials get energy from it. So

10:19 earlier environments they've done trying to simulate environments uh providing what they think would

10:27 been the types of raw materials you have seen would have been lots of

10:31 activity going on spewing C. 02 compounds. Um H two region,

10:40 these kind of things basically inorganic materials C. 02 that can be the

10:45 for things like little trucks. So using these kind of reduced compounds

10:51 see here uh that would have been on early earth. Right? And

10:56 oxidizing those getting energy from it. as we'll learn in, you

11:01 to write uh that these serve as sources. Okay. That can be

11:09 . Right? To more reduced Um I'm sorry that become oxidized.

11:14 then those electrons that are captured go electron transport chain. And then you

11:19 then uh in us, in us who would hand it off the oxygen

11:25 water. But for other things, can use things like nitrate. Don't

11:30 worry about right now. Nitrate is example breathing with nitrate rather than breathing

11:37 oxygen. Micro can do that. so they use strictly they can be

11:42 anaerobic environment. Even intervention materials. as what would have been happening in

11:48 early Earth. Okay. And it's types we look to really in terms

11:53 life elsewhere, you know, like mars and whatnot because of the the

11:59 harsh environments over there. Okay. materials available to them to grow.

12:04 , so bottom line is microprobe carry in particular have been around longer than

12:10 . And uh in terms of them us, right, they've been on

12:15 bodies. We've been evolving for the six million years and they've been along

12:19 the ride, right, Your And so they're an intimate targeting.

12:24 ? So don't you can't be a . Right? Because you're full

12:27 Right, So don't be afraid to your microbes. Okay, They do

12:32 . All right. I will point out throughout the whole semester where they

12:36 come in and help us? so um The accent to checker

12:42 Okay question. So, we're gonna is we get to chapter three

12:50 It's gonna be um not rapid but we're gonna pop questions, put

12:55 timer on it. Read it. of them are, a lot of

12:59 are gonna be super. We have read a lot. So it's gonna

13:03 it'll it'll uh have a good Okay? But within the questions,

13:09 have you know the stuff in the section looks in there to kind of

13:13 things if you need further explanation. we pretty much go information wise in

13:19 same way. Okay, so um look at. Okay, so let

13:25 just set it up here. They're . Okay, so tracker three,

13:32 , recovering in two parts part one pretty much um uh It kind of

13:38 is somewhat from the outside in, , what's on the periphery of the

13:45 cell then going deeper and deeper and the inside the side of that.

13:49 What's in there. So, that's of the approach. So, you

13:54 , very if you if you've gone this um and you want to test

14:00 and I know this or not. is so super simple. All you

14:03 do is take a blank sheet of , draw your favorite microbes shape.

14:07 , Make it a rod if you . Right, and then you

14:10 okay, what do I know about ? Can I fill it all

14:14 Right now? I know what this is all right. What's what's a

14:19 ? How would that? You can through all the terms you can if

14:23 can have your piece of paper and it all out like that. And

14:26 you're doing that exercise in a Just use your paper and pen and

14:31 brain. That's it. And then gonna see how much is, how

14:34 I know it? I got the thing all drawn out and labeled and

14:38 all correct bingo. Right? Or somewhere 50 and 100% whatever you want

14:44 know that answer. But that's an way to really test yourself on this

14:48 . So enough jibber jab first Okay, so which is true regarding

15:00 bacterial cell envelope. Okay, so a look and use process of

15:11 So many people are afraid to pick answer that's already above are correct or

15:16 of the above if it makes Pick it. Okay, so consider

15:21 statement on its own true or Yes or not. Let's see what

15:26 got at the end. Okay. Count down from 10 5432 one.

15:46 let's see we got E. And B. Are possible. Um

15:57 you answered D. You are Okay. All are possible because definition

16:07 an envelope from the first right Right, so the settle classic

16:16 Right. Um what what is external the set of plastic membrane. That's

16:23 . What's going? What what could be pro carry als it can be

16:28 cell wall. It could be that how to membrane uh it may not

16:33 anything out there. Okay, so term envelope, that's why we use

16:39 term. Because it would be because everything is a gram positive. Gram

16:43 , there's variations. So just turn kind of as a way to

16:48 Okay, what's the nature of the ? Is it the features of a

16:51 positive telegram neighbor or something else? , so, envelope is that kind

16:55 that term? How we use that ? Okay. All right. Um

17:02 question. So uh it's about not that one. Sorry, that's

17:11 . Okay, so, in terms quantity, right, molecules per

17:15 the most abundant michael? What? . Okay, got it for

17:47 All right. What do we get you answered C you are correct.

17:52 water. Water molecules in any living . So, the water.

17:58 70% per volume. Okay, so so we're looking at kind of the

18:07 the right 25% called your information molecules D. N. A proteins.

18:15 makes about 25%. Okay, um this plus that approximately 25%.

18:24 uh the rest things like uh uh making up your membrane can uh present

18:33 kind of parts of the basically If you will membrane constituents are about

18:40 5% or so. Um So, water. Right, 70% is

18:45 Okay. And there are gonna be solvent molecules, various types in in

18:51 you know, much into 1% 2% concentration. Okay, Um now,

18:59 you look at pepper white, can . Okay. And the amount

19:06 total weight. So this is e staph Has much more pepper black,

19:15 more than .8%. So it makes has a larger percentage. Why is

19:22 ? It's about staphylococcus. And many them. Not a quick question.

19:27 going out there. Yeah. Staff gram positive. Gram positive and gram

19:34 . Right? And so that difference reflected in the amount of people like

19:38 positive has a lot more than does gram negative. And we're going to

19:43 structure of all that here shortly. , so um okay, so here's

19:51 next question. So this relates to , um let me pause here.

19:59 this uh we got e coli sitting at 34 degrees. Okay,

20:06 had its membrane a slice of its Like this when it's sitting at 34°.

20:15 , so we're gonna jack it jack up the temperature. Okay.

20:21 42. Alright, so again, looks like 42. What will it

20:30 like? Right, hint if you If you need a hint. E

20:35 is going to adjust to this temperature . Right. It is going to

20:41 how is it going to adjust adjust look like A or B.

20:47 okay. It's going to adjust itself live to survive in this now hotter

20:54 . What's it gonna look like when gets there? Okay. So don't

21:04 don't think of it in terms of , there's a change that 42 and

21:08 Coli can't do anything about it. can and will. Okay. All

21:22 , counting down from 20. I predict 50%. It's a 50%

21:39 say thank you. Okay. Okay. If you want before I

21:55 away the answer. Okay, You co at 34°. Right. So the

22:01 is to look at our this beep beep. Right, okay. Um

22:13 relative proportions from that Those forms to forms. Okay, tightly packed forms

22:21 where you see it spacing between. , so you only collect 34.

22:28 , it kind of looks like that gets jacked up kinetic energy.

22:34 Um The membrane is going to respond . Right? Initially. You

22:43 that's a leakage. Probably initially. . Because the membranes are are not

22:50 not fully tightly packed together. It does not ensure survival of

22:55 E coli it's gonna want to minimize . Right membranes are important obviously right

23:00 . The barrier to the outside It's what contains everything in the

23:05 is how stuff flows in and out the membrane and the proteins in there

23:10 you gotta keep that integrity of the . Okay. And so you're gonna

23:14 to patch those fossil that fits tightly , right? Otherwise it's gonna blow

23:21 if you create more bends and things space things apart, it's gonna get

23:28 as you increase temperature, fluid goes hell in handbasket, right? Everything

23:34 flowing out. Okay. So you to keep everything together. Okay,

23:40 you increase town, which is why is the correct answer? Yeah.

23:47 of the kinetic energy of heat as increase going apart, stuff's gonna be

23:52 out is gonna die, tighten it . Get those together and make them

23:58 increase saturation of those fatty acids. everybody line up and then hydrophobic interactions

24:07 that membrane intact. Okay. It mean it's gonna be all the

24:13 There's gonna be still some of Okay. But the proportions are the

24:21 of saturated unsaturated oil tank and you change on the fly. Right?

24:26 got it up 34-33 down. There will be some incremental changes right

24:33 the level of saturation, all in effort to keep that membrane functional and

24:38 making stuff interact. Okay. Any about that. Yes. Yes.

24:50 will go to be If you're gonna it down then you're gonna be

24:55 because now you're gonna compress it, can freeze that was damaged. So

24:59 you want to it's not just the it's all everything's do this. Think

25:04 think of plants that are in different environments are cold weather plants and it's

25:10 same thing to preserve. Remember and . Okay so um Alright so here's

25:17 little bit about membranes I think we've been exposed to lipid bi layer structure

25:24 what they call fluid mosaic model and forth. So I'm not gonna get

25:29 details here but um you know certainly that it is the there is what

25:35 that that membrane structure um the like bacteria have what I call these ester

25:43 linking the fatty acid portion right to glycerol molecule and yellow. Okay.

25:52 Archaea had can have some slight differences having actually is more stable. Okay

25:59 see that in a second. So just some representative types of fatty acids

26:03 common in bacteria. Um The unsaturated acids have one or more double bond

26:13 that bond if it's in the cis . Crazy. King. That's a

26:18 in the previous question. You saw spacing that was due to a little

26:22 and the fatty acid change the spacing apart also. Uh What bacteria can

26:29 is also of the fatty acid chains see here right? That makes it

26:38 its straightness if you will it's gonna uh high temp right to straighten those

26:44 out. Make impact together tight and them a little more stable as

26:50 Okay so our type attachments and so can form what are called ether.

27:00 they can be very long with the carbons long. They can pack together

27:04 tightly. Okay. And that's an of for these thermal Philip archaea particularly

27:10 you're hyper thermal right above 80 Is where you live. Then you

27:18 even start doing this like memorizing these right into something really long. So

27:23 can all packed together very tightly and us saying that really high temperature they

27:28 in. Okay. So um so uh quickly in archaea these are adaptations

27:34 those that live in these really hot . Okay. The bacteria can do

27:38 as well. They just do it they don't have bacteria, don't have

27:42 kinds of uh fossil lipid molecules. have that way. The traditional types

27:48 that we've got here. But nonetheless can manipulate chain length the strangeness of

27:55 to accommodate the function of the So remember the membrane. Right?

28:01 functionality is through the proteins. So , fossil lipids in the membrane is

28:10 1 to 1. Almost. In terms of proteins versus fossil

28:14 Okay and remember the term selective Right? That's due to the fossil

28:21 in the membrane because you know this , right this membrane creates uh differences

28:27 terms of uh like ability to agree solution. Right? The hydrophobic hydrophobic

28:35 . Right. So that water Aquarius uh molecules can interact with the

28:42 portion. Right. So those parts the fossil lipid r water friendly if

28:48 will. Okay, Poland, That's the interior core full of the

28:53 acid chains is very hydrophobic. So they repel polar molecules so that

29:00 just anything can flop in. Gasses can pretty much. Okay,

29:07 small jury non polar type monitors um small polar molecules that water can actually

29:14 through. Right? But things not not glucose or amino acids.

29:20 these kind of things, can there polar They won't be able to pass

29:24 . Right. So membranes are basically by proteins in many of them are

29:30 proteins of course, but they can be enzymes. Right. So,

29:36 of the mitochondrial membrane, right? the cytoplasmic membrane. That's where all

29:41 membranes where all the for respiration are in the membrane so heavily enzyme.

29:49 again, the membrane membranes will differ terms of functionality. Okay, Because

29:53 this, because the proteins in Okay, So but the other point

29:57 is that it is to maintain the of the membrane. So, as

30:03 fluctuate up and down, you got kind of do these changes. So

30:06 ensure that the membranes function e the in them as well around the

30:12 Okay, so that's kind of these of temperature or what that's what it's

30:17 to help maintain the functionality of the the of the membrane. Okay.

30:23 questions about that? Okay. All . Um I should mention uh they

30:31 are also informs sightlines. The chains the same purpose, increase integrity of

30:37 chain and a little bit uh cycle thing is I think it's unique to

30:48 carry out. I don't know I don't know are we can do

30:51 with our fatty acid chains, but precarious can. Okay, um

30:59 so this question, so, now gonna get into membranes. Now,

31:03 gonna talk about how stuff gets Right? So, as you're looking

31:08 this uh just to get some So um uh certainly when we talk

31:14 get the growth in tractor floor uh has to get it to sell right

31:20 still has to eat, right? food markets come across other molecules needed

31:26 metabolize for whether it's to build stuff what have you things have to get

31:31 the outside to the inside. And course, the other way around as

31:34 , there's many different types of transport on, right? And uh there's

31:41 methods of that, as I'm sure already aware of. Okay, and

31:45 is one type here, that yeah, we have uh they're kind

32:03 concentrating them inside the cell, despite fact that there's less of it

32:08 Okay, So let's count down be one that, So Let's see

32:27 Who was 28 that answered on the . What what what is it?

32:35 not only above. Exactly. Exactly . Yeah I could transport. So

32:44 you answer e active transport going against concentration. So two lessons. Don't

32:56 afraid to take none of the above active transport wasn't an option. Okay

33:07 so again it's all about concentration Right? So we have a concentration

33:12 sodium outside. That's this lower than inside. Okay. So they're only

33:20 in there through actor has to be energy process bringing them uphill so to

33:25 . Right takes energy. Right? if you're going up the gradient against

33:31 gradient if you will you gotta put okay. If it's going down the

33:36 there's actually the energy released from Okay so microbes in nature are at

33:43 mercy of their surroundings. It's not all the molecules they need or need

33:48 get rid of are going to be the exact proper concentrations where they don't

33:52 to use any energy at all where all passive processes. No it's never

33:57 right. Sometimes you gotta use energy pump in or out others just will

34:02 passively there's gonna be a mixture. ? And cells have to be able

34:06 deal with that. Okay you're gonna both active transport processes in the

34:11 Okay so um let's look at this before we talk a little bit about

34:17 mechanisms. Okay so which is false . Okay. So that's what we

34:25 about How photonic photonic. Right? that before? Differences between simple and

34:32 diffusion mechanisms. We talked about One member of the base is

34:41 And then this concept at below Okay. So make sure you look

34:48 the arrows where the arrows are Okay. So we get um sucrose

34:56 . Well, you can see going this is outside the cell.

35:00 Going towards where lots of triangles are . Hs are going whereas fewer Hs

35:07 that direction. Oh my pen is working now. All right. So

35:13 pretend to that. Right. And Okay. We're counting down from

35:41 if two heads isn't working better than . Find a different head.

35:46 Maybe get three on the group. right. Okay. Let's see.

36:02 . Which is false. Okay. hipaa tonic sell interior. Okay.

36:15 Okay. Simple diffusion does not involve of a transport protein. That is

36:19 . So simple. That is what diffusion is transport. That's simply uh

36:25 market can pass through the membrane without help or something like water.

36:29 Gasses can pass through membranes by simple without help. So B is

36:35 Group translocation. That is what it like removing based on chemically changing the

36:41 . So, I'm gonna show you are next slide but that's where you

36:45 glucose an example as it comes in gets modified to glucose one phosphate

36:53 Um But because what's coming in is being automatically being changed to something

37:00 Remember diffuse independent of each other. ? So we can keep coming in

37:06 long as it's modified as it comes . Right? So it keeps falling

37:10 . That's what group transportation is Permanent gasses basis. That is

37:15 Making cause issues for inside of cells too basic or specific depending on if

37:22 a weak acid base coming. Um transport mechanism show makes sense and could

37:30 . So we have looking left to . We got initially have hydrogen ions

37:38 pumped out. Okay. And um so it's not working but Right,

37:51 we're sequestering them on this side, they float down the radiant.

37:58 And as they do, they release or they consume energy integrated and release

38:07 . Okay. And so sucrose is up. It's going against the

38:12 That's gonna take energy. So this a concept that will absolutely make

38:17 It will work and it's done all time in yourselves to Okay, so

38:23 photon radiation to see here energy being to produce that. And pro carriers

38:30 proton gradients for lots of stuff. . And so the concept here is

38:35 relates to you know to and energetic concept of couple pair combined a energy

38:47 process for the energy requiring process. . Central concept write down all the

38:54 . And that's what we're doing So we are combining the energy release

39:01 allow the sucrose molecules to go Which requires energy. So this is

39:07 combining of of excuse me back Combining of the two processes right

39:17 energy releasing energy required because it's more . Right? Yes, we're expending

39:23 here to create a proton gradient but not we're not using more https here

39:30 have superpowers come in. Right. would be inefficient. Let's not waste

39:34 DPS to do that. Let's let's another energy releasing process and cover

39:38 Right? Because this is easily not you some protons this but just have

39:44 http process that pumps them out more to do it this way.

39:50 Just um that's done all the If bacteria or anything, they are

39:55 efficient. They're gonna do the thing takes the least energy because you gotta

40:02 these things are competing with each other everything else that's out there in their

40:07 . Any little thing that gives them is going to increase our survival.

40:12 being efficient in metabolism is absolutely something want to do. Okay, so

40:17 one here is is a and I'm my in is not working okay.

40:26 . Circle it but I will circle after class, write a water moves

40:31 the high solid side. Right hip hyper So water moved to the hyper

40:38 , right? It would be moving of the cell if it were a

40:44 hippo tonic sol interior. Okay, water always moves to the highest solid

40:52 . Ok, tire hole. Your system works right? And your kidneys

40:58 whatnot. Okay, um now, just real quick summarizing these processes,

41:07 ? Doesn't require any help. The is strictly based on the going down

41:13 grid. So options higher out it'll flow right? Um facilitated requires

41:21 help of a protein transport protein. , so things that are generally bigger

41:27 , more polar molecules uh these these of molecules can easily penetrate the memories

41:34 need help getting in or out. , um as most, that's the

41:38 reserve for the movement of water. , so remember that the easiest way

41:43 remember this for me at least is will move toward the Saudi side.

41:49 hyper tonic side. Okay, that's preparers tend to and part of most

41:56 cells tend to keep themselves slightly hyper , hyper tonic on the inside because

42:04 allows water to flow in. And they've got a cell wall. Many

42:08 them have a cell wall. So water flows in. It will press

42:13 that cell wall which uh the cytoplasmic will kind of fill up, press

42:18 the cell wall and that kind of maintain the integrity of the cell.

42:21 about balloon in a cardboard box, ? You feel that much more

42:27 It presses against the side of the . Right? Similarly, bacterial cell

42:31 plan sell something for it helps to of in the totality of all

42:36 The cell wall and the hyper tonic helps kind of maintain the integrity of

42:41 cell. So they kind of go in hand. Okay. That's why

42:44 try to keep themselves slightly hyper Okay. Aqua pouring. So I

42:50 that because water can can refuse simple through a membrane. But if if

43:00 cells under osmotic stress, okay, water is flowing into fast,

43:07 It can potentially burst the cell then can recruit aqua porn's to pop into

43:13 membrane and that will facilitate a much rapid transfer movement of water.

43:20 So that's when I quit porn is of come in. If the cell

43:24 under stress automatically and easy to get of water or taking water very

43:29 It'll pop those proportions in there which specific transport of water transporting water.

43:35 . Yeah. Yes, they are from water molecules. That's correct.

43:44 are specific for water molecules. That's right. Um Okay, what else

43:50 we got the group transportation? I mention in the question of abc

43:56 Either two very common transport mechanisms and . Again, the group transportation is

44:02 on the concept of that that molecules diffuse independent of each other.

44:10 So we had glucose out here and came in as glucose and wasn't changed

44:19 we keep flowing in until when if weren't changing glucose as it was just

44:26 coming in outside and glucose coming into glucose will keep coming in until it's

44:33 equal on both sides. And no movement. Okay. But because we

44:37 transforming it glucose, glucose six phosphate ever builds up inside the cell so

44:43 can keep coming in, coming in in because it's immediately going to this

44:48 product that kind of helps keep carbohydrates it uses energy sources that bacteria the

44:58 transport system. This is um transport types of carbohydrates, sugars and et

45:05 . But it does rely on a that binds the particular Saw you there

45:10 some specificity there and that will in transporter itself and it isn't dependent energy

45:18 process that's going against the grain to it in. Okay. But

45:22 these are two very common mechanisms you for transporting bacteria. Archaea and then

45:28 membrane permian. Right, so this um something that can be an issue

45:33 terms of interest. Inter Senator ph , so and uh you know like

45:39 things that are moderate uh in terms ph where I try to keep the

45:46 page between around seven plus or Right, 6 to 6 to eight

45:51 . And um the the influx of like a weak acid. So here

45:58 example of a weak acid is a base. Okay, so contrast to

46:03 strong acid. Think of hcl Hcl when you pop that in water

46:11 all the hydrogen ions and chloride Right? None of this is

46:17 Hcl Oh, completely dissolved. So weak acid. That's not the

46:23 You always have all three species Okay. And so the the one

46:34 the problem is this that can be acetic acid for example. Okay,

46:39 organic acid. So the neutral form the one that's small enough to kind

46:44 squeeze through the membrane and get inside cell. And that's where it can

46:49 partially. So weak acid basically partially . Right? That's when you have

46:55 three species always present because it's not complete dissociation of like a strong acid

47:00 . Okay, so it's it's the form that comes in then. And

47:05 again associates or um or produces Okay, so inside the cell that

47:13 be an issue right? Slightly drop rise depending on the base or acid

47:20 in then it still has to counteract . Right? So whether it's through

47:25 through buffers like amino acids, amino have a positive charge and they can

47:33 the effect of an acid base. . And it's you know, it's

47:38 uh this kind of membrane permeable gas . That's really what a lot of

47:44 are. But you see I can in different foods like citric acid is

47:49 common food attitude and one of its of its uses is as a way

47:54 inhibit growth is our growth inhibiting these of molecules can inhibit the growth and

47:59 they used as preservatives and different Supergrass is very common. Another one

48:04 uh you don't even know this but called P A B A benzoate

48:10 There's another food out of there. has the same features of these membrane

48:13 gasses causing internal problems and growth. um any questions about transport stuff?

48:28 , because really through the small smallness the water molecule. Okay, so

48:34 it's also water is not a it slightly positively charged as opposed to a

48:39 negative positive charge on it around the of but I think merely because of

48:45 small size saving the squeezer so it's it's not gonna be an efficient transport

48:50 it's enough under under normal circumstances where where the cell is okay with

48:56 But like I said, it is where it's a greater need for water

48:59 inside or out, it'll pop in aqua porn's to speed things up but

49:03 actually is enough to smallest actually work normal circumstances. Okay. The other

49:18 . Um likely if there were a be imbalance of salts inside or outside

49:25 cell. So there's a lot of outside the cell decreased so much that

49:29 that will force water in where the now becomes hyper time. So it

49:31 of would depend on the external salt typically if they're too high or way

49:35 low that can influence the flow. . Oh so buffers but the buffers

49:47 of the cellar. Typically things like acids themselves can have a neutralizing

49:52 So I still have amino acids inside as solid. And that can help

49:57 kind of counteract the effect of astro . Okay okay so now so

50:06 Okay uh kind of one of those a not all pro but among bacteria

50:18 main bacterias ways as we'll see and may think okay number one I put

50:27 two terms on here. Right these taxonomic terms. Okay so like like

50:35 genus genus homo homo sapiens man. so firm acute is a tectonic group

50:43 bacteria as a rodeo bacteria. And several other names but only because I've

50:49 these names pop up on like an . Cat or or dental exam whatever

50:54 what it's called. I see my exam so I figured well let me

50:57 pop these in there So you you say you haven't seen it before.

51:01 the firm accused are basically bacteria that gram positive. Right? And the

51:06 are gram negatives. So this test developed Early 20th century late 19th century

51:16 it's still today. Okay um It it can be the basis for

51:25 You can pretty much lump if you're bacteria you can do a grandstanding may

51:30 your first delineation you know it's gonna different for that group. Or maybe

51:37 doesn't stand but nonetheless you can perform first step and figure out what you've

51:42 . But diagnostically medically people um it tell you depending on the nature of

51:50 sample. You can tell you you you can make a preliminary diagnosis if

51:54 have a throat swab and you put on a blood honor right gram stain

52:01 you're seeing gram positive toxin chains. And it's producing a particular reaction

52:08 We'll talk about blood on later but can already tell you that you've got

52:13 throat or use the appropriate antibiotics if have a grand negative oxide impaired coming

52:22 of your central cerebral spinal fluid. can tell you you got meningitis so

52:28 utility in this day and it's still to this day. Okay so so

52:34 gonna kind of delve into what are basics of gram positive and gram negative

52:39 . Okay and so here we The questions. Okay so so it's

52:47 be about four of these in a with these pictures on. Okay so

52:53 see if we can how do we here? Okay we're looking for what

53:01 the structure labeled A. And open polls sorry. Okay now you can

53:12 O. L. P. Stands for. Mhm. Okay let's

53:37 down from 10 What is the one should have your 5 600 thing.

53:48 ? Yeah okay I can fix that that I put numbers so it wouldn't

54:01 feeling so do that. Yeah, about that. So you said it

54:11 letters to pick your choice so Good. Mhm. Okay so let's

54:39 . Okay. E yeah he is LPS player so that is correct.

54:53 right. I got to do the thing on the next slide. So

54:56 look at that plan. A Alright so this is relaxing for

55:09 What is G? What is And G. Is pointing to the

55:15 black strand? Black strand in the . So G is pointing to the

55:23 thread. You will. Okay count from six. So again the Black

55:59 G. What is it? Yep it is it is that okay?

56:13 let's see. Okay This 1 2 of bacterial cell envelopes. I'm

56:26 Hey do this again. Um Which represents little protein. Little protein.

57:07 . Okay counting down from 10. let's see. F. Yes lippo

57:44 . Oh alright. Another one. label component paintings acid cheers acid Count

59:03 from 987. Okay. To the is correct. So excited. Okay

59:24 these next couple are not um quicker but you can this be posted.

59:31 can use it maybe as a checklist you know what I find very we

59:37 some of these where they were um I think that of course uh here's

59:42 these are the answers for all those . Don't. Right now I'm gonna

59:47 these but of course on this slide all these previous pictures, type one

59:53 the gram gram negative, of Right. Gram positive. Okay,

60:02 very thick pepper of like hand Right, very thin. And the

60:08 negative. Okay so let's kind of through the structures here. Okay so

60:15 cell wall and that Mexico in addition the uh water flowing in and kind

60:22 pressing against that wall helps maintain integrity of course certain production there. So

60:28 itself. So it's this chain of two molecules of acid and I'm not

60:36 ask you to draw the chemical structures these things. Okay. But it's

60:42 the name you should be familiar Okay, so they come together in

60:46 polymer kind of analogous maybe to a phosphate backbone of A. D.

60:51 . A. Right or nucleic Um They form a polymer that's kind

60:57 basically stretches around the cell the whole of the cell. This is a

61:01 shaped hill obviously. Um and they know the term is called, say

61:05 , kind of the fully formed structure the cell. Uh It's it's uh

61:11 very porous. It's more or less porous. Not restrictive to a lot

61:16 molecules. Okay. But but you the cytoplasmic membrane that can of course

61:21 much more restrictive but in terms of ferocity of the cell wall, it's

61:26 not great. I mean it's it's porous and so there is a peptide

61:31 . So there's a sugar component and a peptide peptide component is what creates

61:37 cross bridges. Okay. That you here and across bridges occur on the

61:45 of the end of steel, ceramic . That's where the bridges occur.

61:49 , between those and when a a cell cell wall synthesis is a is

61:58 major target of many antibiotics. And so collectively what they do basically

62:05 can interfere with the production of a bridge in many cases um interfere with

62:11 enzyme from the process because there's many that are involved in synthesizing the cell

62:16 and all of them are potential targets antibiotics um amoxicillin. Um lots of

62:24 . Okay, our targets here are here and if you if you break

62:29 the peptide linkages, okay, that destabilizes the whole cell wall structure.

62:36 , so it kind of begins to apart and so membrane release begins to

62:43 through. Okay, so it'll kind bubble through like this and eventually lice

62:49 really what the effect of these kind antibiotics are, is to destabilize so

62:54 and and lice the cell. now there's certainly are differences in susceptibility

63:00 the gram negative and gram positive and mention shortly. Okay, so this

63:06 just a blow up of the connection these uh these residues of the cell

63:14 and so um here it's not an we've all heard of kind of unique

63:21 acid that you find in the cell . And this is where the connection

63:25 made. And so when it's made have an alimony, there's two realities

63:31 the end and one of them gets place as a cross bridges. Okay

63:37 I can mention penicillin is a targets components that are involved in synthesizing cell

63:44 uh basically combined to hear me back combined here. Okay. And in

63:56 so that's it basically blocks the enzyme making the cross language physical block to

64:05 that linkage. And so again destabilizing wall. Um But of course material

64:11 don't stand for that. They evolve they get resistant forms. And so

64:18 the penicillin resistance, there's a number different mechanisms. One of the major

64:23 is the presence of a metal academies basically just destroyed the penicillin altogether.

64:30 um banco resistance is a little Okay so if bank of myostatin itself

64:40 has its mechanism by basically sitting here blocking access by the enzyme that creates

64:46 cross link. What would be a of resistance that it could use to

64:53 that what kind of change might occur now it's no longer susceptible to Bank

64:59 mine. Any ideas remember bacteria can take it is gonna change? What

65:07 change here? Yeah. Yeah you're of on the right track there.

65:21 what if um what if the bacteria of having to al means maybe change

65:27 to something else they've seen where that become resistant types. It becomes uh

65:33 or lactic acid. And now the of minuses doesn't recognize because you changed

65:42 by altering the chemical and now it's . And so that's a easy

65:49 Not easy but you know single mutation cause that change and it becomes

65:54 Okay so um now let's see. so side by side gram positive.

66:05 kind of start here at the Right So here is the in both

66:10 of course you have that psychopathic Right? We use the term for

66:16 negative. I mean it's a cell obviously but we also we use the

66:21 inner membrane because the gram negative has additional member outside of that.

66:28 But the inner membrane of gram negative member and grandpa are equivalent.

66:33 It's the it's that boundary right between inside and the outside. Right?

66:39 psychopathic membrane. So now what happens that? It's gonna be different.

66:44 so you see a very thick like layer and gram positives to gram negative

66:49 may be one or two layers Um And then attachments of cell wall

66:57 member. Right so you have tyco into gram positive. Right? The

67:03 going through. Okay if anybody has construction and you're familiar with what rebar

67:11 rebar is in concrete and metal rods concrete to reinforce the concrete?

67:16 So very much the same way helps reinforce the cell wall. Okay.

67:22 and allows it to attach to that . Okay. And gram negatives.

67:29 have the attachment here to the outer . So you have an outer membrane

67:34 an inner membrane. Okay. Um the attachment of the cell wall by

67:41 proteins attached to that outer membrane. space. Right. Remember those pictures

67:48 the question? There was like a label. F right, was actually

67:54 this right here. The space, space between the membranes of para plastic

68:00 . Okay. And so in a negatives of course that there wouldn't be

68:04 paraplegic space in the gram positive because don't have to membrane boundaries. There's

68:08 one. Okay, so um the the para plasm that environment can contain

68:15 types of proteins, enzymes, transport , etcetera. Okay, um now

68:23 out on this outer layer, The Lps, liberal poly zachariah,

68:30 . Little fat, sugar and sugar combination. Okay, so even on

68:37 halves of the outer membrane this half this half. Right, are

68:44 The differences are so on the outer of that memory. You have these

68:48 long policy Sacha ride polymers. The what they call the call the

68:55 old policy Sacha ride long stretch of . Okay, um you have you

69:02 have different types of transport molecules in . The permeability will differ between the

69:10 outer membrane. Inner inner membrane more outer membrane uh a little more generic

69:21 more network more more non specific. . And but it gets more specific

69:27 you get into the cytoplasmic membrane or membrane. Okay. Um and so

69:33 that LPS layer that provides the negative um unique features the grand positive doesn't

69:40 . Okay that LPS flare can can an antigen. You can induce antibody

69:47 in some cases um can uh um the movement of molecules. Right?

69:57 why you see differences in gram positive gram negatives in terms of antibiotics,

70:02 treatments like disinfectants and things. You use a gram negative deposit together cause

70:07 gonna see differences in these kind of treatments. And so because of this

70:13 membrane okay. Will will retard certain and that will have the same effect

70:21 the gram positive. And so that's the identity of a gram negative gram

70:26 and an infection is important to know of the type of antibiotic you have

70:32 administer. So yes, there's there's that both types are susceptible to but

70:39 some types of both aren't susceptible It depends on the nature of the

70:43 . Okay, so a little closer at the graham at the LPS

70:49 So this indoor toxin. We'll talk this later in the semester. But

70:55 is something to consider if it's a negative infection. Okay. Because if

71:04 if you as the gram negative is . Right? And by your own

71:10 system or and or in conjunction with , the cells lice, right,

71:18 die and then the materials release and where the problem can come in.

71:22 , So the end of toxin effect really the liquid A material is what

71:30 the endo toxin? Okay. Right . And so that is only released

71:38 the cell is life and dies. , it's intact. No problem.

71:43 . And so in a nutshell, it all nuts and bolts, but

71:46 talk about it later. But when top material released to the body,

71:51 if you have a what we call infection, it's in your blood then

71:57 material is released and it goes to of your immune system selves and they

72:02 over hyped right, produces a much reaction than it would have just a

72:10 infection by spreading throughout the body. lots of immune system cells can interact

72:15 it and there's a much heightened Too much for your body to handle

72:20 to shock, you can die. ? So again, any gram negative

72:24 that ability. But of course that us as those that cause infection.

72:29 . And particularly if the infection has quite serious and it's in your

72:34 then you really have to be aware this and the toxic effect.

72:38 like you said, well, we'll into more details later, but for

72:42 something to put something be aware that gram negative infection can be quite

72:47 particularly from this effect. Okay and the old. Right so again that

72:55 that can cause that cause but it's so it's about the molecules making up

73:06 old party Sacharow right. They can an immune response. You can use

73:11 . This is like 50 years ago more now. We identified O.

73:16 H. And particularly in cold life in terrible organisms. Right so medically

73:26 . Nikolai's uh salmonella for example caused poisoning. Right I was referred to

73:32 Chipotle E coli right has caused a of outbreaks through contaminated produce. All

73:38 let us know what not. Um by having identified these engines which is

73:45 the immunological reaction. Right so we antibodies to different engines and allows us

73:53 rapidly identify one of these types uh there's an outbreak. Right so we

73:59 seven suspect that's what it is. we have the antibodies that we can

74:03 it real quick and go oh yeah reacts it's 157. Okay so it

74:08 a form of rapid I. Okay for certain types again kind of

74:13 uh one H. Is kind of thing about E. Coli and salmonella

74:16 very similar organisms. Okay so um okay so let me just mention that's

74:25 this should be gram positive. Okay and that's the s layer. Okay

74:34 the s layer is external to the I think gram positive. The black

74:43 , right. Remember has a plastic . Okay. I think the is

74:50 a net net of proteins around the . Um It's very porous um functions

75:01 it are still kind of iffy. 100% sure. You see it.

75:07 types that have it. It can provide attachment in some cases. Um

75:15 been hard to study because it's something is lost when the organism is cultured

75:21 the lab and then you kind of to keep it alive. It kind

75:26 loses the S. Layer. So it's been something that's not been

75:30 to figure out what's going on with . But there is some evidence that

75:34 yeah, they could have the importance some types in terms of maybe being

75:39 virulent factory disease or attachment, these of things. So it's kind of

75:44 a feature Grant pauses but and not cases do we act exactly know what

75:49 absolute function of it is. But we know it's there. Okay

75:55 Any questions? Okay so let's let's need to stop So we'll stop there

76:09 we'll pick it up on Tuesday. they were saying please stop. Okay

76:13 will Tuesday folks. Thanks have a weekend.

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