Nature's Incredible ROTATING MOTOR (It’s Electric!) - Smarter Every Day 300

0:00 Hey, it's me, Destin.

0:00 Welcome back to Smarter Every Day.

0:02 This is the 300th episode, which is cool.

0:04 Thank you so much for watching.

0:06 I was on the internet the other day.

0:07 I was just scrolling on my phone.

0:08 I was probably wasting too much time.

0:10 But I came across this amazing animation that blew my mind.

0:15 It's a motor that appears to be made out of molecules.

0:19 And I'm a mechanical engineer.

0:21 When I saw this thing, I was like, that's a motor.

0:24 That's a spinny thing that has a power source.

0:29 It has an axel of some sort, and it is moving.

0:33 Furthermore, this one, I have a little switch here,

0:35 can reverse directions, which is amazing.

0:38 So I thought I've got to get to the bottom

0:42 of this because the implications for a biomechanical motor are insane.

0:48 Now, specifically, the thing this is called is called a flagellar motor.

0:52 You may have heard of the flagellum on the back of sperm or on bacteria.

0:56 That's what this is.

0:57 A flagellum is that whipy thing

0:59 in the the single cellular organism that helps provide locomotion.

1:03 But I've never thought about that thing has to spin,

1:07 which means it has to have a shaft it rotates around.

1:11 It's just the implications are wild.

1:14 So the more I got to reading about this flagellar motor is what it's called,

1:18 the more I realized this is a really big topic,

1:22 not only in biomechanics and things like that, but in philosophy.

1:26 The complexity of a flagellar motor implies

1:30 many things about the origin of life.

1:32 And I'm not going to answer that in this video,

1:36 but it raises questions that people are debating,

1:39 and they're talking about, how can this be?

1:42 It's so complex.

1:44 Well, You don't understand the time involved with how this came.

1:47 All this is fascinating.

1:49 So I just wanted to see it.

1:51 So to get to the bottom of how this thing is,

1:54 I decided to go to the researchers that made the image,

1:57 which is a guy at Vanderbilt University.

1:59 So I'm a Smarter Every Day.

2:01 I did this about a month ago.

2:02 Just got in the car, drove to Vanderbilt,

2:04 and we're going to learn about a flagellar motor.

2:07 Let's go get Smarter Every Day.

2:12 So I bobbed and weaved my way across the Vanderbilt University campus

2:15 till I got to the School of Pharmacology and connected with Prashant sing.

2:19 Yeah, doing well.

2:20 Nice to meet you.

2:20 How are you?

2:21 Yeah.

2:22 Prashant is a Senior Research Associate at the Iverson Laboratory at Vanderbilt.

2:26 Just to give us whole context here,

2:28 you have written a paper with your team in Nature...

2:31 What was the- [P] Microbiology.

2:33 [D] Nature Microbiology.

2:34 It's about a motor that's made of molecules that's on bacteria.

2:39 Yes.

2:39 Okay, can you show me where on a bacteria the motor is?

2:43 [P] Sure.

2:44 If You see on the screen here, this is how a bacteria looks like.

2:48 The bacteria has two membranes.

2:50 These two membranes protects the bacteria from getting disrupted.

2:54 [D] We're talking about the outer shell of the bacteria.

2:56 [P] Outer shell of the bacteria.

2:57 [D] Okay.

2:57 [P] If you see here, there will be The two membranes, the orange and the blue.

3:02 Now, zoom into that.

3:03 [D] Okay, so it's almost like a submarine.

3:06 Forgive me, Prashant.

3:07 I'm going to say a bunch of engineering terms because I'm an engineer.

3:10 [P] I understand.

3:10 [D] It feels like a submarine with the outer

3:14 hull and then the inner pressure hull.

3:16 [P] That's correct.

3:17 My dad was a submariner himself.

3:18 [D] Was he really?

3:19 [P] Yeah, he was an Indian Navy submariner for 15 years.

3:23 [D] So this bacteria, in my head, is like a submarine.

3:25 [P] Yes.

3:26 [D] Okay.

3:26 And is this the propeller of the submarine?

3:29 [P] That is correct.

3:30 This is the propeller or the flagella.

3:32 Now, this submarine does not have a rudder.

3:35 It doesn't have a rudder, but it uses a propeller to turn as well as swim.

3:40 So what we see here, the two membranes that are here,

3:44 and there's proton filled in here.

3:46 [D] Did you say proton?

3:47 [P] Yeah, it's filled with protons, hydrogen ions in here.

3:51 [D] Oh, hydrogen ions.

3:52 Okay.

3:53 [P] The hydrogen ions in here filled,

3:55 and on the inside here, there's very little hydrogen ion.

3:59 There's a It's a gradient.

4:00 [D] Forgive me.

4:01 We have to go slow for me.

4:02 When you say proton, you're meaning an atom that is lacking an electron?

4:06 [P] Yes, just a proton.

4:07 It's a hydrogen ion.

4:08 This is high concentration of protons in this region

4:13 and low concentration of proton in the inside of the bacteria.

4:17 Now, protons, every time there's a gradient, for example, there's a dam,

4:21 water is up there, and there's a lower, there's less water,

4:24 there's a gradient, energy can be generated, or it could be used,

4:28 that potential energy could be used to kinetic energy.

4:30 [D] There's a potential difference of electrochemical force of some sort?

4:36 [P] Yes.

4:37 That's the gradient that this motor uses to turn itself.

4:41 What happens is, if you see here, this flagella,

4:44 which is a propeller, is connected to a motor system.

4:48 [D] How does it know when to turn the motor on?

4:49 [P] There are sensors on the outside of the bacteria.

4:55 Once it knows that there's a threat or there's more energy near me,

5:00 it senses that it gets a chemical signal,

5:03 and there's a cascade of signals that go through.

5:07 One of the protein well known for this is called CHeY,

5:12 C-H-E and Y, capital Y, QY.

5:14 The moment it senses that I need to run away

5:17 from this location or I want to go to a different location,

5:20 that protein comes and binds to it,

5:22 and it encourages the motor to turn in clockwise direction.

5:28 [D] Okay, so we need to talk about what you just

5:30 said because you just created a coordinate system inside the bacteria.

5:36 You put sensors on the outside of the bacteria.

5:38 Well, it already exists.

5:40 Okay, there are sensors on the outside of the bacteria.

5:42 Somehow the bacteria knows where a sensor is triggered and it

5:49 knows how to trigger what motor on what side of the bacteria.

5:52 [P] Yes, and how to turn it.

5:54 [D] And which direction to turn it?

5:57 [P] Which direction.

5:57 So that particular protein it will make it go in clockwise.

6:02 This is clockwise direction.

6:03 When it is not attached to it, it will go in counterclockwise.

6:08 The default motion is counterclockwise.

6:10 When the motor turns counterclockwise- [D]

6:12 You say counterclockwise from which direction?

6:14 [P] From this direction.

6:14 [D] From the outside.

6:15 [P] From the outside, yeah.

6:16 [D] The outside, okay.

6:17 [P] Yeah.

6:17 So counterclockwise would be this.

6:19 And when the motor is running in counterclockwise,

6:22 the bacteria will swim forward.

6:24 So it's just the board goes straight.

6:26 [D] And that has to do with the shape of… If I were to design

6:29 this, I would say that would have to do with the shape of the impeller.

6:33 So the tail?

6:34 [P] Yes.

6:35 The way the flagella is made, it's like a whip.

6:38 So when it starts rotating, it thrusts,

6:41 the force goes backwards and it moves it forward.

6:44 Now, you would think that it would also do

6:46 the same thing when it's going in the opposite direction, right?

6:48 [D] Yeah.

6:49 [P] Now, what happens is when it's going in the counterclockwise,

6:53 there are multiple flagellas on the bacteria body.

6:56 All of them start forming a bundle,

6:59 and multiple propellers form into one big propeller

7:03 and pushes this straight and it goes boom, straight.

7:06 Now, when it has to sense it like there's a danger,

7:08 I need to stop, I need to reanalyze my situation gradient,

7:11 I need to test, I need my sensors on and test it again, it turns clockwise.

7:16 When it does that, the bundle opens up.

7:18 When they open up, it just pauses the whole

7:21 bacteria and the bacteria starts stumbling all around.

7:24 [D] Starts floating, yeah.

7:25 It no longer has a certain… There's got to be a word Latin in here, taxis.

7:30 [P] Yeah, chemotaxis.

7:32 Chemotaxis, yeah.

7:33 Exactly.

7:34 We call this whole process of bacteria's mobility like chemotaxis.

7:37 It's a chemical signal that allows the bacteria

7:40 to taxis or move from one place to another.

7:43 Everything happens in milliseconds.

7:45 There are some videos that show bacteria moving from one place to another,

7:48 and it's just like crashing.

7:50 It's a biased, random walk.

7:52 Researchers have done this experiment.

7:55 There's a petri dish,

7:55 and they put food in the center and put bacteria on the edges of it.

8:00 You would think the bacteria would go straight to the food,

8:02 but no, it just goes a little bit straight,

8:04 then turns around and goes in the wrong direction,

8:06 realizes, Oh, I'm in the wrong direction, goes back.

8:09 That, as a person, you think random.

8:12 [D] I'm getting emotional now because there's

8:14 a missile that I've worked on in the past,

8:16 and it has what we call pulse-width modulation control.

8:20 And so what we do is we take the fins

8:22 on the side of the missile and we dither them.

8:24 We go like that.

8:26 And then all we do is we bias the dithering up or down.

8:30 We go...

8:33 So it's constantly moving,

8:34 but we just bias it just a little bit in order to make a movement.

8:38 And so what took us a long time to figure out, you're just describing it.

8:45 This molecule or this bacteria has an operating system.

8:48 It has sensors.

8:50 It has effectors.

8:53 It has actuators.

8:54 [P] Exactly.

8:55 [D] And it has feedback.

8:56 And I'm getting emotional.

8:59 Because It's a neat design is what I'll say.

9:02 [P] It is.

9:03 Over the years, this design has evolved to be so perfect.

9:07 It just takes some time, but it does go where it's supposed to go.

9:11 It doesn't have eyes like we do.

9:12 It figures out by sensing and moving in directions.

9:15 [D] It's an emergent behavior based on a few inputs.

9:18 Emergent behavior?

9:19 [P] Yeah, that's a good term.

9:21 [D] The structure of this motor, is it well known in the community?

9:24 In all of research, people know about this?

9:28 [P] They have seen a low resolution structure.

9:31 Basically, if I blur this up, they have known that for 15, 20 years.

9:35 They have known it looks like this blob.

9:37 There's a ring at the bottom, there's a ring on the top.

9:40 But what we have is a high-resolution structure,

9:42 meaning we can see each and every amino acid.

9:45 [D] I noticed on your video, it's almost like a big gear and a small gear.

9:51 [P] Yes, that small gear is MOT-AB.

9:53 That is what the proton comes through, and that's what turns this thing.

9:56 [D] Prash explained that the MOT-AB,

9:58 the little part that spins like an ion pump,

10:00 is able to interact with this band of red called Fly-G,

10:05 and that has the ability to pivot 180 degrees,

10:08 which enables the motor to change directions.

10:11 So in your animation, you have one small gear going in.

10:14 Is it literally Is that really one small gear or are there many all around?

10:16 [P] It can employ more if it needs more torque.

10:21 It's two, three, four, five, six, seven, eight, nine, 10, 11.

10:24 Up to 11 is what we see can fit on there, but maybe 12 or 13 as well.

10:29 But we don't know the exact number how many can be employed.

10:31 But it is a sequential increase depending on the load of the flagella.

10:36 [D] Okay, so I'm going to get all engineering with you now.

10:39 If you have a torque, you have to have a thing to react against.

10:44 So So that little pinion, I'll call it, the little...

10:47 What did you call it?

10:49 Mot AB.

10:49 Mot AB?

10:50 [P] Mot, M-O-T-A-B.

10:52 [D] Mot AB.

10:53 [P] Yeah.

10:53 [D] So Mot AB is this little thing that's driving it.

10:55 [P] Yes.

10:57 [D] Is it pinned to the sidewall or something?

10:59 What is it?

11:00 [P] It's also in this inner membrane.

11:03 So it's right here.

11:04 So there's multiple colors that you see, orange, cream, and green.

11:09 This all is one Mot AB.

11:11 And it takes protons or hydrogen ions

11:13 from the top and goes into the low gradient here.

11:17 And as it's doing it, it makes interaction with this red protein here.

11:21 And this rotates, and it causes the motor to rotate.

11:24 [D] Okay, but it's pinned in that wall.

11:27 [P] Yes, it is pinned in this membrane, but it can go around,

11:30 and it can shift a little bit in and out.

11:32 Mot-ab is only turning in one direction.

11:35 It cannot go in two directions.

11:36 Here, the energy is only going from top to bottom.

11:39 So how does this motor go in two directions?

11:41 And that does because the MOT-AB, first it's outside,

11:44 but when it has to go in the other direction,

11:48 the red protein turns 180 degree, pulls the MOT-AB with it,

11:52 and then MOT-AB keeps doing what it's doing.

11:54 It's churning in the same way,

11:55 but that causes the motor to go in the other direction.

11:57 [D] It's like shifting into reverse in a manual transmission car.

12:01 [P] Yeah, it's almost like back to you has a reverse gear.

12:05 It reminds me of my motor that my grandfather

12:08 worked on where there's copper coils that he's making,

12:12 putting in these old, rebuilding these motors and putting fresh copper coils.

12:15 It reminds me of that structure.

12:18 [D] Because your grandfather was an electrical engineer, right?

12:20 [P] Electrical Engineer.

12:21 He used to build and rebuild motors for factory at factories.

12:25 [D] Is it fun to know that you're

12:27 working on motors now just like your grandfather?

12:28 [P] Yes, it is.

12:30 It feels very rewarding to be working

12:34 on something that my grandfather worked in the past.

12:37 Obviously not the same scale, not the same thing.

12:40 But just to know that I'm working on motors is fun.

12:45 It's rewarding.

12:45 [D] Okay, this is incredible.

12:47 I love this.

12:48 We're going to go back and talk to Prash later

12:50 to understand how he got these images of the motor.

12:52 But to get more context, let's go over and talk to Dr.

12:55 Tina Iverson, who runs this lab.

12:57 She's the PI or the Principal Investigator.

12:59 This is Dr.

13:00 Iverson, and this is your lab, right?

13:02 [T] This is my lab.

13:03 [D] So congratulations on getting this published.

13:05 That's a big deal.

13:06 And simply put, what have you found here?

13:09 [T] So we are looking at really this nuts and bolts of how bacteria can move,

13:15 how they can move toward something that attracts them,

13:18 like a food source, and how they can move

13:21 away from something that would kill them, like an antibiotic.

13:24 Bacteria are moving toward a food source as driven by their metabolism.

13:29 [D] Okay.

13:29 [T] And metabolism is like the foods that you eat.

13:32 It's how you bring in energy into your body.

13:35 But we're asking that question at a larger level,

13:38 not just for bacteria, but for human cells.

13:41 How does metabolism affect what our cells do

13:45 in a way that dictates their self- fate.

13:48 And so we were trying to understand just at a general level,

13:53 why does metabolism change what cells do?

13:57 [D] I feel like every time we as humans

13:59 have the the ability to see smaller or farther.

14:02 We make big discoveries.

14:03 [T] Yeah.

14:04 [D] Do you feel that?

14:05 [T] Oh, yeah.

14:06 I think that one of the ways the entire field is going now

14:11 is there's been this ability to image very small things with fine detail,

14:18 but medium and larger things in the cell with more blob-like characteristics.

14:25 Some of the new technologies are now getting

14:28 to these larger assemblies proteins at finer details.

14:32 [D] So we're seeing the overall system.

14:34 [T] Yes.

14:34 So before we were putting the system together from component parts,

14:38 and now we're seeing the system more and more intact.

14:42 And these bridges between the molecules at an individual level,

14:47 which can tell us a lot about how they work.

14:49 But molecules together working in concert tells us much, much more.

14:53 [D] So we've got this motor that for the first

14:56 time we can see an image down to the protein level.

14:58 The question is, how do we get that image?

15:00 How is Prash able to see this motor and understand its

15:04 component parts in a way we haven't been able to understand previously?

15:07 To answer this question,

15:08 Prash took me over to the imaging lab where they use a series

15:11 of cryo-electron microscopes to look

15:12 at the structures to understand how they work.

15:15 He introduced me to Miriam and Scott, who were kind enough to show me around.

15:19 So now we're with Scott and Miriam, and these are the imaging experts.

15:22 Am I saying that correctly?

15:24 [S] Sure.

15:24 [M] Yeah.

15:25 [D] Okay.

15:25 Yeah.

15:25 Does that work?

15:26 [S] Absolutely.

15:26 So all of our sample goes onto a grid that's right here.

15:30 It's a mesh work on there.

15:32 [D] What's it made out of?

15:34 [M] Copper.

15:34 [S] Copper.

15:35 So they can make it made out of a copper, gold.

15:36 There's some other materials that we use for other various niche purposes.

15:41 Most of them are copper.

15:42 [M] You have whatever sample you have that's in a buffer.

15:45 It will get plunge frozen.

15:47 You literally just drop it in, drop your sample

15:50 into liquid ethane and just gets flash frozen.

15:53 So your sample is in vitreous ice.

15:55 [S] We're just making a network that can hold

15:57 little tiny sheets of ice with protein trapped in it.

16:00 [M] So that's what you start off with.

16:01 And then after plunging, then we load it into that little...

16:06 Cartridge.

16:07 [S] Our middle room here is our Glacius microscope.

16:09 So we'll walk in and look at it.

16:11 So this is the Glacius.

16:12 This is our screening microscope.

16:14 [D] So this is like a quick look.

16:16 [S] It's a quick look.

16:16 We have a source at the top that transmits

16:19 an electron beam all the way through the column,

16:22 and we put our sample in the middle and a detector at the bottom.

16:24 [D] So you're shooting through it?

16:26 [S] We're shooting transmission.

16:26 We are going all the way through that sample.

16:28 [D] The process that the scientists use to get these images is incredible,

16:32 and I'm going to take a crack

16:33 at explaining it with a super sophisticated animation style.

16:36 So behold, markers and paper.

16:39 All right, so there's two types of bacteria at work here.

16:42 You've got Salmonella and E.

16:44 Coli.

16:44 Now, Salmonella, that's where the flagellum motor is located.

16:49 That's these little yellow things back here.

16:50 So that's the flagellum, and that's the little motor.

16:53 Ecoli, a different bacteria,

16:54 has a little factory in it that can make things if you tell it what to do.

16:59 So So this process is called transformation.

17:02 So basically, I just took that motor off,

17:05 and I'm not going to put the motor itself into the factory in Ecoli.

17:10 I'm going to put the instructions of how to make the motor into Ecoli.

17:15 Ecoli is not the only type of cell that has a little factory like

17:18 this, but this is the one that the scientists

17:20 chose to 3D print this particular motor.

17:22 This is called transformation.

17:24 This little factory goes to work, right?

17:26 It makes a bunch of these little motors, and then you have a bacterial cell

17:32 that has all these little protein structures in it.

17:35 The act of creating this is called expression.

17:38 We are now going to take all

17:39 of these motors and do this process called purification.

17:43 We're going to pop this and we're going to use this grid and we're

17:46 going to basically dump all of the stuff

17:50 that's been purified onto this grid array.

17:52 We're going to flash freeze it.

17:54 And then after that, we're going to use this really fancy 200 kVA microscope

17:59 and We're going to go through and we're going to look at the grid.

18:02 Now, when we look at the grid, we're going to screen these.

18:05 So this is like a course view of what we're doing.

18:07 We're going to go through and we're going to say,

18:09 Hey, look, there's one right there.

18:11 That's important.

18:12 Over here.

18:13 Oh, that's important.

18:14 And then you're going to go all the way through this whole grid,

18:16 look in and see which one has motors in it.

18:18 How many motors does it have?

18:19 It might be a lot.

18:20 You're then going to move it over to the big microscope, the 300 KVA microscope.

18:25 And that's where we're really going to take our close up images.

18:28 So what they do is they zoom in, and then

18:30 they're going to take 50 frames of each individual little motor.

18:36 The reason they have to do that is because at this level,

18:38 you're down at the angstrom type level, like the atomic level.

18:41 Things shake a little bit down at that level.

18:43 So you have to take 50 images in order to compile that together,

18:47 you have to make sure you take out that dithering.

18:49 So at that point, you then have an image of a structure.

18:52 Now, that structure at that point, it could be like this, it could be like

18:56 this, it could be at any number of different aspects.

18:59 And Prash is going to tell us what he does with that information.

19:02 Before we talk to Prash,

19:04 if you want to learn more about microscopy and how the scientists do all

19:07 this, I've got way more information over on a video on the second channel,

19:11 which is Smarter Every Day 2.

19:12 Go check that out if you want to learn more about this.

19:14 So you get the images from the microscope.

19:17 [P] So when you get the images from the microscope,

19:20 they look somewhat like this.

19:21 [D] And I can see the little crown-looking thing there.

19:24 Is that the bottom of a motor?

19:26 [P] Yeah, this is the bottom.

19:28 This is the top view.

19:29 So I would say that this is how it looks.

19:32 This motor right here is the view of this one.

19:35 Then this view right here is a side view, something like this.

19:40 We click on all of these particles,

19:43 meaning we pick those proteins by hand and using the computer.

19:46 We run a program of 2D classification,

19:49 meaning we run a program where all these particles that has

19:53 been picked so far are similar-looking particles are put together into classes.

19:57 What we see here is some are just junks,

20:01 and some are actually our protein complexes.

20:04 [D] You go through there and you pick the ones that are the good stuff.

20:07 [P] Yes, exactly.

20:09 This looks like a good stuff.

20:10 This is a good complex.

20:13 This is good, this is good, but these are not.

20:16 We don't select those, but select the good particles

20:19 and put them together into a program for 3D modeling now.

20:23 We have 2D classes.

20:24 Once we have 2D classes, we put them together here to get a 3D version.

20:30 [D] Oh, so you build a 3D model.

20:32 You make these shapes actually match up.

20:35 [P] Yes.

20:35 Each of those classes on pictures that we saw,

20:38 we start matching them up as to which one is the top view,

20:41 which is the side view, and program starts doing matching those up,

20:44 and it does a very good job at doing that.

20:47 [D] It's really the ability to replicate so many.

20:49 That's the secret sauce.

20:50 You have the transformation, putting that information into Ecoli to replicate,

20:55 and then Ecoli expresses it.

20:56 That's expression and then purification.

20:59 Transformation, expression, purification, that's how you get it done.

21:03 [P] Once we get the 3D model, it looks something like this.

21:07 We can see all sides.

21:09 Now what we see is a low-resolution model.

21:12 We try to collect all the good signals and remove all

21:15 the bad signals and try to come up with a high-resolution structure.

21:19 What you see here is an 8 angstrom.

21:21 From here, 8 angstrom to 4 angstrom,

21:22 it took us about two weeks to get there, 2-3 weeks.

21:25 [D] You're removing bad data to get to the high resolution.

21:28 [P] Get to the high resolution.

21:29 [D] Then once you get to the high resolution,

21:31 then you actually start drawing and mapping the proteins.

21:33 [P] Yes, exactly.

21:34 To get this map, we're trying to put the pieces

21:36 in, the puzzle pieces in, and try to find what protein,

21:40 what amino acid goes in which place.

21:42 So since we know the sequence of the protein, we have the pieces.

21:45 We just have to fit it in this electron density.

21:47 [D] So we have these 2D images that we

21:50 wrapped together using software into a 3D model.

21:53 And at this point, we know it's made up of proteins,

21:56 which are made up of amino acids.

21:58 And so the question I had is, how do you know what chemical is where?

22:02 And it's my understanding that biochemists are just smart,

22:04 and they know that certain amino acids are shaped in certain ways,

22:09 like physical shapes.

22:10 So it's like a puzzle piece, and they just know what they look like.

22:12 So they're like, oh, here's blobafil, or here's quadraline.

22:16 I don't know these words,

22:18 but they can physically put the puzzle pieces in on the computer,

22:22 and they can figure out what the structure looks like, which is incredible.

22:25 [P] So if you see this curve, there's a curve here.

22:28 [D] The coil.

22:29 [P] The coil, and that's alpha helix.

22:31 This coil, now we know alpha helix, only certain amino acids make in a certain

22:36 orientation or sequence would make that coil.

22:39 So this prior information helps us trace this puzzle.

22:43 So if you see now, We can fill these gaps with these proteins.

22:48 [D] This is a shape a biochemist person would not be intimidated by this shape.

22:52 [P] No, that's very common.

22:53 It's commonly found in almost every protein.

22:57 Not every protein, but like 90%- [D] It's intimidating to me,

23:00 hah looks like a bunch of squiggles.

23:02 Yeah, but this is normal.

23:03 [P] This is normal.

23:04 [D] This is easily interpretable data.

23:07 [P] Yes, it is.

23:08 [D] Did you map these by hand and then just turn the image on?

23:11 Is that what just happened?

23:12 Or did you tell the computer to find the shape?

23:14 [P] No, we mapped this.

23:15 Our previous researchers have mapped this in the past.

23:18 We use the information as like, Oh, they have done part of this.

23:22 Let's use that and see if that fits in here.

23:25 If it does, it's good.

23:26 If not, we go in and do it by hand.

23:28 [D] Wow.

23:28 [P] Yeah, it can be doing one at a time.

23:31 It can take weeks to months sometimes, depending on how big your protein is.

23:35 [D] But you like it?

23:35 [P] Oh, yes.

23:36 This is the best part.

23:37 This is where we get answers.

23:38 This is what we have been doing all the work for.

23:42 Even when we are driving here, we are so excited.

23:44 What will I find today?

23:45 So now we come back and sit down, drink our coffee, and we're like, Oh.

23:49 So for example, I can go here and be like,

23:51 Let me see if there's any bonds being formed.

23:54 I go, Turn on the distances and angle.

23:56 So there's a definite interaction between this and this.

23:59 Maybe that is what's stabilizing this complex so well.

24:02 They're forming some bond between two amino acid.

24:05 So this is what gets us excited that we

24:08 have found the interaction that are happening in this complex,

24:12 what stabilizes this.

24:13 And if we disrupt this, this can disrupt this can disrupt the motor.

24:16 This can disrupt the connection it's having

24:18 or interaction it is having with other proteins.

24:21 [D] Once you disrupt this motor,

24:23 if you could destroy the motor or if you could stabilize it,

24:27 whatever, just if you had control,

24:30 then you could start to do things that would affect the chemotaxis?

24:34 [P] Yes, bacterial chemotaxis.

24:36 [D] You could disrupt the ability for the thing to move where it wants to go.

24:40 [P] Yeah, exactly.

24:41 For infection, stopping the bacteria is almost like having an antibiotic,

24:45 but not with an antibiotic, because bacteria can get resistant to antibiotic.

24:49 This is one of the many other options that people

24:51 are- [D] Maybe you get to invent a new word.

24:53 Instead of an antibiotic, it's a letharga biotic.

24:56 [both laughing] You get to slow them down.

24:59 [P] I like that.

25:00 [D] Thank you very much.

25:01 [P] Thank you so much.

25:02 [D] So the flagellar motor exists, and it's amazing.

25:06 It's complex, and it reminds me of an electric motor, and I love it.

25:10 I love this thing, and I think it's incredible.

25:14 There are implications for the fact that something so complex

25:18 exists and is so integral to the creation of human life.

25:22 I mean, this is fascinating stuff.

25:25 So it also opens up a huge debate.

25:29 People say, well, how can something this complex come to be out of nothing?

25:33 The logic goes like this.

25:34 If this motor system is composed of complex individual parts,

25:38 and all these parts work together to perform the overall function of rotating,

25:42 then how did the individual parts come to be?

25:45 Did it all have to happen at the same time?

25:48 Or is there some evolutionary advantage

25:50 to the cell for every intermediate stage of development?

25:53 Is 15% of this motor advantageous to the cell?

25:57 What function would 50% of the structure perform?

26:00 What were the steps these components took to assemble

26:02 into such a complex molecular machine in the first place?

26:06 Scientists are trying to figure this out,

26:08 and I encourage you to read their papers.

26:10 Many seem to be focusing on the Type 3 secretion system,

26:13 which works like a hypodermic needle that a cell can use to inject other things.

26:17 This device looks similar, but it's quite different in its protein structure.

26:22 The complexity and origin of the bacterial

26:24 flagellar motor is a really interesting conundrum.

26:27 As I was a younger man,

26:28 and I would read things on the I would find people saying,

26:31 Hey, you got to believe all this over here.

26:33 People say, Hey, you got to believe all this over here.

26:36 There's a big war going on.

26:37 It's between science and faith.

26:39 You're either in one camp or the other.

26:41 Get your flag and figure out where you're going to put your flag.

26:43 And the more I have matured and started

26:47 to not really care about defending where my flag is,

26:50 the more I've been able to learn from people no matter where they are.

26:54 I'm still working on this.

26:56 There's a really interesting book that I'm reading.

26:58 I can't speak for everything in the book.

26:59 I'm not done with it.

27:00 It's called Where the Conflict Really Lies.

27:04 It talks about this interplay between science, religion, naturalism.

27:10 It's very interesting.

27:11 It goes more into the areas of philosophy,

27:13 and I love it because it challenges me, and it's fantastic.

27:17 So this is what I would encourage you.

27:19 If you have your flag in a camp somewhere,

27:22 I would encourage you to not defend a flag.

27:25 I would encourage you to look at a flagellar motor and just

27:29 think about it and think about how it is and what it be.

27:34 It's a fantastic thing to think about.

27:36 How did this get here?

27:38 You have intelligence and you get to make up your mind.

27:42 And I love that about consciousness.

27:44 I love that about life.

27:46 And so for me, the flagellar motor makes me happy.

27:49 I feel joy.

27:50 You know how when you go outside at night and you look up at the stars

27:53 and you see all these stars and you feel small and you feel wonder,

27:58 that's what this makes me feel like, even though it is small.

28:01 I feel awe and reverence toward this thing.

28:04 And as a Christian, this makes me want to thank God that it exists.

28:09 I feel compelled with gratitude that this thing is so awesome.

28:12 So that's just where I'm at.

28:14 But what I would encourage you to do is just think critically.

28:17 You have a brain.

28:18 Don't defend a flag.

28:19 Just think about how things are.

28:21 And I hope you are very happy and experience the same

28:25 joy I feel about this, no matter what you think about it.

28:29 So anyway, enough about that.

28:31 I want to say thank you to everybody that supports Smarter Every Day on Patreon.

28:36 You'll notice there's not a sponsor on this video.

28:39 I just wanted to make this for you, and I just want to say thank

28:43 you to everybody that supports at Patreon.com/smartereveryday.

28:47 You're smart.

28:48 You know what I'm doing.

28:49 I'm just going around asking questions, and that's all these videos are.

28:52 So this is the 300th episode.

28:55 So thank you for supporting Smarter Every Day to allow me to do this so long.

28:59 And I would encourage you, if you're interested,

29:01 I would ask to consider supporting at Patreon.com/smartereveryday.

29:05 to let me keep doing it.

29:07 And if that's not your thing,

29:08 totally cool with it because I'm having fun and I'm grateful to all of you.

29:13 Thank you for watching.

29:14 I am Destin.

29:15 You're getting Smarter Every Day.

29:16 If you'd like to learn more about the deep detail of all this stuff,

29:20 I'll have a video on the second channel that goes

29:22 into more discussions about how all this works, but I love it.

29:25 Big thanks to everybody at Vanderbilt for helping me make this video.

29:28 I'm Destin.

29:29 You're getting Smarter Every Day.

29:31 Have a good one.

29:32 Bye.