WEBVTT - Forget Going Viral - Bacterial Communication is Awesome 0:00:00.160 --> 0:00:07.160 Brought to you by Toyota. Let's go places. Welcome to 0:00:07.360 --> 0:00:14.319 Forward Thinking. Hey there, and welcome to Forward Thinking, the 0:00:14.480 --> 0:00:17.120 podcast that looks at the future and says, I think 0:00:17.120 --> 0:00:19.680 I'll call my boss. Then I'm gonna hack and cough 0:00:19.720 --> 0:00:23.560 and we'see, he'll swear. I got some strange disease. I'm 0:00:23.640 --> 0:00:28.440 Jonathan Strickland, and I'm Joe McCormick and Lauren. It seems 0:00:28.480 --> 0:00:32.240 like you were just so eager to talk about bacteria. 0:00:32.560 --> 0:00:36.400 I always want to talk about bacteria. They do great stuff. 0:00:36.400 --> 0:00:41.600 They they make cheese possible kind of. They help us digesting. Yeah, 0:00:41.640 --> 0:00:45.360 they make us real sick sometimes that's the best. It's 0:00:45.440 --> 0:00:50.400 very important. Well yeah, sure, yes, we've talked about before 0:00:50.440 --> 0:00:53.360 about how bacteria actually make up more of us than 0:00:53.440 --> 0:00:59.320 we do. What by cell count mass? Yeah, I think 0:00:59.320 --> 0:01:01.880 by mass it's a thing like four pounds. It's it's 0:01:01.880 --> 0:01:05.360 not all that much. But yeah, we came across this 0:01:05.440 --> 0:01:10.400 really interesting article in Scientific American about bacteria, and even 0:01:10.440 --> 0:01:12.280 though we've kind of sort of talked about it a 0:01:12.280 --> 0:01:14.960 little bit in the past, I really wanted to do 0:01:15.000 --> 0:01:18.119 another episode about it because bacteria can talk to each 0:01:18.160 --> 0:01:21.759 other and that's so cool. But Before we get to that, 0:01:21.920 --> 0:01:25.760 let's do a quick overview on just what bacteria are 0:01:26.000 --> 0:01:30.479 and why, other than the pure scientific inquiry into how 0:01:30.520 --> 0:01:34.920 bacteria communicate, like how that would practically affect us, right, right, 0:01:35.000 --> 0:01:37.720 So first off, I mean this is going to be 0:01:38.280 --> 0:01:42.240 a review on like elementary science level, but it's important 0:01:42.280 --> 0:01:46.440 to build the foundation. Bacteria are very small organisms. Um wait, 0:01:46.440 --> 0:01:50.080 wait a second, yes, what do you mean small? So 0:01:50.120 --> 0:01:53.920 when we call say, Matt Frederick a bacterium, we're not 0:01:54.000 --> 0:01:57.160 meaning that literally because he's he's actually the size of 0:01:57.240 --> 0:02:03.680 many bacteria. How many more than four? Uh so at 0:02:03.760 --> 0:02:08.760 least three dozen? We're talking about usually a single cell organism, right, 0:02:08.800 --> 0:02:13.280 That's typically what bacteria are. Um. They lack though exactly 0:02:13.320 --> 0:02:17.440 that fact is going to become interestingly complicated. They lack 0:02:17.520 --> 0:02:20.520 chlorophyll because if they had chlorophyll, then they would be 0:02:20.840 --> 0:02:23.280 probably more along the lines of the plant kingdom than 0:02:23.520 --> 0:02:28.240 of their own. They actually belong to a kingdom called prokaryota, 0:02:28.400 --> 0:02:30.800 and that is they are they are not the only 0:02:30.960 --> 0:02:34.760 inhabitants of that kingdom. Um Way, they lack a nucleus, 0:02:34.800 --> 0:02:38.680 which is what puts them there. They're prokaryotic. That means 0:02:38.680 --> 0:02:42.240 that they do not have a nucleus or other membrane 0:02:42.280 --> 0:02:46.160 bound organelles inside of them cell command center. Yeah. Yeah, 0:02:46.160 --> 0:02:49.000 they're just sell soup inside kind of sort of. Yeah, 0:02:49.080 --> 0:02:51.520 it's not like you know, the or the cells that 0:02:51.560 --> 0:02:54.160 we are in us. They're you karyotic. They have a 0:02:54.240 --> 0:02:58.360 nucleus and membrane bound organelles and things like that. The 0:02:58.440 --> 0:03:03.880 other organism that within that kingdom is our chea. Those 0:03:03.919 --> 0:03:10.720 are the other prokaryotic organisms. So their DNA is just 0:03:10.800 --> 0:03:13.320 contained within the cell itself. There's no nucleus there to 0:03:13.360 --> 0:03:17.040 hold it, unlike ours. It's a circular chain of DNA 0:03:17.560 --> 0:03:22.440 molecules that inhabit the bacteria or bacteria um because that's 0:03:22.440 --> 0:03:25.640 the singular, right. How Come every time I searched for 0:03:25.680 --> 0:03:29.320 stock images of bacteria, they're like a few kinds. They're 0:03:29.360 --> 0:03:34.240 they're like the hot dog bacteria, and the cheese puff bacteria, 0:03:34.360 --> 0:03:37.960 and the and then I think some spiral gigs. Spiral 0:03:38.000 --> 0:03:42.480 gigs I always think of like Arby's curly fries. Yeah, yes, 0:03:42.920 --> 0:03:46.640 it's because it's delicious bacteria. But I like my bacteria 0:03:46.720 --> 0:03:50.520 covered in melted cheese sauce. Uh yeah, that's because the 0:03:50.560 --> 0:03:55.720 bacteria do come in and generally in three general three shapes, right, 0:03:56.040 --> 0:04:00.480 you've got the spherical ones, you've got the rod shaped bacteria, 0:04:00.520 --> 0:04:03.880 and then you have the spiral the spiro keet bacteria, 0:04:03.920 --> 0:04:07.800 which always makes me think of The Simpsons because there's 0:04:07.920 --> 0:04:11.840 the part where uh, Lisa's teacher explains that she has 0:04:11.920 --> 0:04:15.440 lyme disease and then Ralph Wiggam draws a spiro keat 0:04:15.520 --> 0:04:19.480 for her and in her get well, card I drew 0:04:19.520 --> 0:04:25.320 you was spiro keat. You didn't see that season? No, no, no, 0:04:25.360 --> 0:04:28.200 that was the one where Lisa develops a crush on 0:04:28.240 --> 0:04:33.520 the replacement teacher who comes in because he's he's very 0:04:33.560 --> 0:04:36.200 smooth talking and doesn't talk down to the students, and 0:04:36.240 --> 0:04:39.200 she just falls in love with him. Uh. We usually 0:04:39.320 --> 0:04:43.159 use the word bacteria rather than bacteria um because we 0:04:43.320 --> 0:04:45.760 tend to talk about a whole mess of them. It's 0:04:46.160 --> 0:04:48.720 very rare that you're going to talk about a single 0:04:49.360 --> 0:04:53.640 bacterium because steria rarely get lonely. No, they usually they 0:04:53.720 --> 0:04:56.040 usually got a group of friends together, and if they 0:04:56.040 --> 0:04:58.280 don't have a big group of friends together, they work 0:04:58.440 --> 0:05:02.839 really hard to change that. Yeah. So that's those Those 0:05:02.839 --> 0:05:07.800 are your general like simple foundational facts. About bacteria, and 0:05:07.920 --> 0:05:11.279 like Lauren was saying, there are tons of different kinds. 0:05:11.279 --> 0:05:15.160 Even within these three main classifications of shapes, there are 0:05:15.160 --> 0:05:17.560 tons of different kinds. Some of them are beneficial to us, 0:05:17.880 --> 0:05:20.359 some of them can make you very very ill, and 0:05:20.400 --> 0:05:23.320 some of them we just don't really react, like there's 0:05:23.360 --> 0:05:26.680 no interaction, and some are pretty neutral. Yeah. Yeah, it's 0:05:26.760 --> 0:05:28.680 kind of like a you know, a D and D campaign. Really, 0:05:29.160 --> 0:05:31.159 you've got some, You've got some that are like lawful good, 0:05:31.160 --> 0:05:33.359 and then you get kaolic evil, and then true neutral. 0:05:34.480 --> 0:05:37.760 So those are your basic types. Uh. And then we 0:05:38.040 --> 0:05:40.920 got to get on over to the how how bacteria, 0:05:41.040 --> 0:05:44.320 like the unwanted kind, the stuff we don't want in 0:05:44.320 --> 0:05:48.000 our systems, how those can interact with us and make 0:05:48.120 --> 0:05:52.359 us not feel so great. And that's one of the 0:05:52.400 --> 0:05:56.360 primary reasons why we are interested as a human population, 0:05:56.400 --> 0:05:58.880 not the three of us in this room, in studying bacteria, 0:05:59.320 --> 0:06:03.040 because of aously, people getting sick is bad. We want 0:06:03.080 --> 0:06:06.800 that to happen less often. Uh, And instead it seems 0:06:06.839 --> 0:06:11.240 to be happening more often. And our primary means of 0:06:11.360 --> 0:06:14.880 fighting bacteria tends to be using the use of antibiotics. 0:06:15.320 --> 0:06:17.640 But we're kind of in an arms race, aren't we. Yeah, 0:06:17.800 --> 0:06:20.159 that's a great way of putting it is. It's that 0:06:20.360 --> 0:06:25.000 we come up with an antibiotic, and then bacteria can 0:06:25.040 --> 0:06:29.960 sometimes find a means to resist that antibiotic, thus making 0:06:29.960 --> 0:06:34.840 it less effective. Any population of bacteria that still remain 0:06:35.040 --> 0:06:38.920 after an antibiotic has been moved through a system are 0:06:39.440 --> 0:06:44.480 more capable of resisting it in the future, thus creating 0:06:44.800 --> 0:06:48.200 kind of super bacteria. Yeah, it's evolution on the micro scale. 0:06:48.200 --> 0:06:50.599 And in this way, bacteria are kind of like the borg. 0:06:51.040 --> 0:06:53.000 I mean, what happens when you use a weapon on 0:06:53.040 --> 0:06:57.159 the borg? They immediately recognize that attack. Once if the 0:06:57.160 --> 0:07:00.640 attack is successful, they recognize it, they adjust their shields 0:07:00.680 --> 0:07:02.680 so that now it absorbs it. That's why you always 0:07:02.680 --> 0:07:07.320 have to vary the frequency, right, except in antibiotics, we 0:07:07.360 --> 0:07:09.640 can't really vary the frequency. And we talked a lot 0:07:09.680 --> 0:07:12.360 about this, well, not about borgs, but about this general 0:07:12.400 --> 0:07:16.680 topic in our episode the antibiotic Dilemma, which came out 0:07:16.760 --> 0:07:22.000 in March. But right, you know, antibiotics, the point of 0:07:22.040 --> 0:07:26.400 them is to slow down the growth of bacteria, you know, 0:07:26.480 --> 0:07:29.400 either kill them or slow them down to the point 0:07:29.400 --> 0:07:32.200 that your immune system can successfully fight off an infection. 0:07:32.520 --> 0:07:36.080 On its own. And the problem here is is that 0:07:36.120 --> 0:07:38.960 bacteria again have a lot of friends hanging out with them. 0:07:39.000 --> 0:07:42.480 They multiply so fast and so densely that colonies can 0:07:42.480 --> 0:07:48.400 evolve to be resistant really really quickly. They divide by fission, 0:07:48.560 --> 0:07:52.640 and they can do that within twelve hours, so within 0:07:52.640 --> 0:07:57.160 the twenty four hour period the population can increase significantly. Yeah, 0:07:57.240 --> 0:07:59.880 and like you guys were saying, it's hard for antibiotics 0:07:59.880 --> 0:08:03.600 to keep up with them because the mechanisms through which 0:08:03.600 --> 0:08:08.640 antibiotics kill bacteria tend to be really easily foiled by evolution. 0:08:08.760 --> 0:08:12.680 For example, lots of antibiotics kill by basically just stabbing 0:08:12.800 --> 0:08:16.560 bacteria in their outer cell walls, uh, kind of sort 0:08:16.560 --> 0:08:19.280 of just making them rupture all of their cell guts 0:08:19.280 --> 0:08:24.520 spill out dead bacteria. But you know, critters with stronger 0:08:24.560 --> 0:08:27.720 cell walls will survive and multiply, and future generations will 0:08:27.960 --> 0:08:33.680 be less likely to be harmed by stabbing. So this 0:08:33.800 --> 0:08:36.880 is particularly an issue because we have become so dependent 0:08:36.960 --> 0:08:41.480 on antibiotics to solve bacterial disease problems, like we use 0:08:41.559 --> 0:08:44.920 them as blanket measures, and even healthy animals that we 0:08:45.080 --> 0:08:49.240 wind up eating we prescribe them for sometimes non relevant 0:08:49.320 --> 0:08:53.480 diseases or in cases that won't really significantly help the patient. 0:08:54.160 --> 0:08:56.840 We use them as blanket measures in like our hand 0:08:56.880 --> 0:09:00.600 soaps and dish soaps, instead of just promoting say, food 0:09:00.640 --> 0:09:05.760 handling and regular old handwashing, which are usually just as effective. 0:09:06.720 --> 0:09:09.680 And this would be I mean, this gets exacerbated if 0:09:09.760 --> 0:09:13.760 there's a misdiagnosis. Obviously, if you were prescribed antibiotics for 0:09:13.840 --> 0:09:16.120 something that ended up being a viral infection, it's not 0:09:16.240 --> 0:09:19.720 going to help you at all. Viral infections are different 0:09:19.760 --> 0:09:22.920 from bacterial infections. Yeah, so this is like if in 0:09:22.960 --> 0:09:26.080 a universe populated by borg we used our best weapon 0:09:26.160 --> 0:09:28.800 against the borg too, I don't know, clean the outside 0:09:28.800 --> 0:09:33.480 of our starships and then yeah, oh accidentally went past 0:09:33.520 --> 0:09:35.440 a board foot. Now they know how to stop it. 0:09:36.640 --> 0:09:38.920 That would that would be foolish of us. But yet 0:09:39.000 --> 0:09:41.000 that's maybe that was a horrible analogy. I don't know. 0:09:41.040 --> 0:09:43.320 That's kind of what we do occasionally with you know. 0:09:43.440 --> 0:09:47.520 It's it's not that people are uh, you know, kind 0:09:47.520 --> 0:09:51.320 of doing a blanket carpet bombing with antibiotics. It's just 0:09:51.360 --> 0:09:54.360 that that it has been such an effective tool and 0:09:54.400 --> 0:09:59.120 has saved so many lives that the the desire to 0:09:59.280 --> 0:10:02.880 go to that early is very strong, oh Sharon. And 0:10:02.960 --> 0:10:08.120 before we realized that that these antibiotic resistant strains were 0:10:08.160 --> 0:10:10.559 starting to develop, it seemed like a really great plan. 0:10:11.200 --> 0:10:12.800 And but then all of a sudden we wound up 0:10:12.800 --> 0:10:14.839 with stuff like um m R s A, which I 0:10:14.840 --> 0:10:18.079 could never pronounce the full name of. I'm not even 0:10:18.120 --> 0:10:25.440 gonna try. The cyllin resistant staff willocaucus arius. Yeah, go Joe, right, 0:10:26.679 --> 0:10:30.439 that sounds good to me. Methicillin resistant staff lacaucus arius. 0:10:30.520 --> 0:10:33.240 Well there we go, now, you know, and knowing's half 0:10:33.280 --> 0:10:36.520 the battle. The other half is red lacing. The other 0:10:36.559 --> 0:10:38.840 way you could say is that it's staff. It's a 0:10:38.880 --> 0:10:44.000 staff infection that has become resistant to the antibiotic methyicillin. Yes, 0:10:44.600 --> 0:10:48.800 because normally staff infections are just skin infections, but in hospitals, 0:10:48.880 --> 0:10:52.720 m R. S A can cause deadly blood and surgical 0:10:52.720 --> 0:10:56.880 infections and pneumonia, nasty stuff like that. It's this is 0:10:56.920 --> 0:11:01.840 also where we got stuff like gnarrhea that never goes away. Yeah, 0:11:02.000 --> 0:11:06.640 bad times. So okay, we still need to use antibiotics 0:11:06.640 --> 0:11:09.240 in some situations. They still save lots and lots of 0:11:09.280 --> 0:11:15.520 lives unless we can find some other way of fighting bacteria, 0:11:15.920 --> 0:11:20.199 and that leads us into a discussion about how bacteria 0:11:20.480 --> 0:11:23.280 act on moss, because there's a there's a question that 0:11:23.360 --> 0:11:26.200 you have to ask yourself when you start looking at 0:11:26.440 --> 0:11:32.120 bacterial behavior, which is, how can something this this very simple, 0:11:32.360 --> 0:11:37.520 single celled organism, how does it know quote unquote when 0:11:37.800 --> 0:11:43.600 to unleash the kraken of bacterial infection upon a host? Right, 0:11:43.679 --> 0:11:48.439 Because even even bacteria that can typically be very dangerous 0:11:48.520 --> 0:11:52.560 to us are not always in their dangerous state. There 0:11:52.559 --> 0:11:54.840 there's a few factors that go into whether or not 0:11:54.920 --> 0:11:58.000 bacteria make you sick, and that includes, um, whether or 0:11:58.040 --> 0:12:00.360 not they're pathogenic, which is whether or not they're in 0:12:00.400 --> 0:12:03.720 like attack mode, and how virulent they are, which is, um, 0:12:04.160 --> 0:12:08.760 how little stabby, Yeah, that's a good way of putting it. Yeah, 0:12:08.760 --> 0:12:12.720 And are they angry? How hungry are they? And sometimes 0:12:12.880 --> 0:12:15.480 it's just that they have to wait until the population 0:12:15.559 --> 0:12:18.880 is a certain size and then that's when they unleashed 0:12:18.920 --> 0:12:21.199 the dogs of war or the cracker however, whatever you 0:12:21.200 --> 0:12:23.600 want to I'm gonna just keep saying unleashed stuff. It's 0:12:23.600 --> 0:12:27.320 like you're you're you're playing StarCraft and you're trying to 0:12:27.360 --> 0:12:30.440 save up for a zerk swarm right right, and you 0:12:30.520 --> 0:12:32.840 just you know there's going to be one. You just 0:12:33.600 --> 0:12:36.839 you're not sure when. And you know it's not gonna 0:12:36.880 --> 0:12:39.000 be something like You're not gonna have a case where 0:12:39.280 --> 0:12:41.439 it's just one or two things coming at you. It's 0:12:41.440 --> 0:12:44.040 just gonna be a mass of them. I I apologize 0:12:44.040 --> 0:12:46.760 if I said that wrong. I've never actually played star Craft. 0:12:46.880 --> 0:12:49.160 I just know that's a thing. You just lost cred 0:12:49.240 --> 0:12:53.040 with pg O. You're like way ahead, all right, so 0:12:53.040 --> 0:12:56.640 so so yeah, So it turns out that bacteria, despite 0:12:56.679 --> 0:13:00.960 not having a brain or even a cell nucleus, communicate 0:13:01.000 --> 0:13:03.840 with each other, and it's in a really interesting way. 0:13:03.920 --> 0:13:07.720 The way this was sort of observed early on was 0:13:07.840 --> 0:13:11.720 through um an experiment in which some researchers were using 0:13:11.880 --> 0:13:15.520 bacteria called Vibrio fisher i, which is a type of 0:13:15.559 --> 0:13:20.360 bacteria that is luminescent. When when there are a certain 0:13:20.440 --> 0:13:26.280 number of the bacteria, then they all uh in sync 0:13:26.600 --> 0:13:30.840 luminesce they glow. Yeah, so they actually there was a 0:13:30.880 --> 0:13:34.840 Ted talk we watched in which the presenter showed a 0:13:34.880 --> 0:13:37.160 picture of a flask of this stuff and it's just 0:13:37.240 --> 0:13:39.640 glowing green. It looks like, you know, the stuff you 0:13:39.640 --> 0:13:43.360 would see in a glow stick, but in this case 0:13:43.400 --> 0:13:46.120 it was just the bacteria that had reached a certain 0:13:46.160 --> 0:13:50.560 population density. And that's the key. They call it quorum sensing. 0:13:51.360 --> 0:13:54.480 And by that what they mean is the bacteria are 0:13:54.559 --> 0:14:00.520 able to produce the sort of molecular um uh signals, 0:14:00.559 --> 0:14:03.480 let's say, chemicals that that are essentially saying hey, I'm 0:14:03.559 --> 0:14:07.400 here and uh. They're called auto inducers, and they also 0:14:07.480 --> 0:14:11.040 have sensors. This this essentially a receptor that's on the 0:14:11.080 --> 0:14:16.160 bacterial cell wall. So their message molecules and in ways 0:14:16.200 --> 0:14:20.440 of detecting right. And so what will happen is if 0:14:20.680 --> 0:14:24.040 the bacterium is all by, it's lonesome, it sends these 0:14:24.040 --> 0:14:28.760 autoinducers out which just float away and nothing gets picked up. Yeah, 0:14:28.880 --> 0:14:31.880 it's not targeted. It's not like I am bacteria or 0:14:31.920 --> 0:14:35.560 Bacterium Laura, and I am aiming at Bacterium Jonathan to 0:14:35.640 --> 0:14:38.640 send a message. It's just like a Hey. It's kind 0:14:38.640 --> 0:14:41.720 of like imagine that you are stranded on a deserted 0:14:41.760 --> 0:14:44.880 island and you have your your collection of bottles and 0:14:44.920 --> 0:14:47.440 collection of parchment, and you're writing down messages and throwing 0:14:47.480 --> 0:14:49.680 them into the ocean, hoping someone picks them up. Same 0:14:49.680 --> 0:14:51.800 sort of thing. Or it could be that you are 0:14:52.000 --> 0:14:57.400 in a post zombie outbreak safe haven with a radio 0:14:57.600 --> 0:15:01.320 transmitter and you're transmitting your location in your coordinates and saying, hey, 0:15:01.360 --> 0:15:04.400 we should we humans should band together, right, But you're 0:15:04.440 --> 0:15:08.280 doing it, you know, on a frequency that you've picked 0:15:08.320 --> 0:15:10.600 at random that people may or may not be listening to. 0:15:11.200 --> 0:15:15.880 So as you get more of the bacteria cells around 0:15:16.560 --> 0:15:20.120 the there grows, there's the density that grows of these 0:15:20.200 --> 0:15:22.880 auto inducer these molecules that are sent out because all 0:15:22.920 --> 0:15:25.080 of them are are admitting them, right, So you're sending 0:15:25.080 --> 0:15:27.680 out more and more because the population is growing. When 0:15:27.680 --> 0:15:31.200 you reach a certain threshold, then the bacterial cells will 0:15:31.240 --> 0:15:36.240 be able to detect the presence of those auto inducers, 0:15:36.280 --> 0:15:40.560 and that is the message that to say, hey, express 0:15:40.720 --> 0:15:45.840 this gene that does something. In the case of the 0:15:45.880 --> 0:15:50.240 Fibrio fisheri bacteria, it was to luminess to to glow. 0:15:50.840 --> 0:15:53.600 Another way that this gene can be expressed, though, is 0:15:53.640 --> 0:15:56.280 in the production of biofilms, which is something I'm gonna 0:15:56.320 --> 0:15:58.520 talk about in a minute, right. Yeah, there's a few 0:15:58.560 --> 0:16:03.960 different auto inducer signals that can happen. The on and 0:16:04.040 --> 0:16:07.560 off switch of of pathogenesis um kind of scale of 0:16:07.640 --> 0:16:12.720 virulence um, the formation of protective spores around individual bacterium 0:16:12.720 --> 0:16:16.040 which which tell the bacterium, hey, time to bunker down 0:16:16.080 --> 0:16:19.680 for a minute and hold on uh. And the also 0:16:19.720 --> 0:16:23.200 the creation of certain substances stuff like that. Yeah, And 0:16:23.240 --> 0:16:26.440 it's kind of neat because this is not limited just 0:16:26.640 --> 0:16:31.360 to intra species communication. In other words, you could have 0:16:31.560 --> 0:16:35.960 a population of bacteria that can all communicate with one another. 0:16:36.080 --> 0:16:39.800 The the auto inducers that they are emitting our only 0:16:40.320 --> 0:16:43.560 keyed to members of that bacteria. In other words, you 0:16:43.560 --> 0:16:45.160 can think of it like a key that will only 0:16:45.200 --> 0:16:49.280 fit a specific lock. But they can also emit other 0:16:49.560 --> 0:16:53.960 auto inducers that are more universal that all bacteria can accept. 0:16:53.960 --> 0:16:57.040 The microbes are uniting against us, they kind of are. 0:16:57.400 --> 0:17:01.240 Although researchers suspect that this thro out of a competition 0:17:01.280 --> 0:17:05.680 for resources between different species. There's one particular auto inducer 0:17:05.720 --> 0:17:08.879 called AI too, which a whole lot of species are 0:17:08.960 --> 0:17:12.760 keyed into. And and it seems like like quorum sensing 0:17:13.240 --> 0:17:17.080 espionage goes on between species to like try to confuse 0:17:17.200 --> 0:17:22.399 different different other bugs. You might have one population of 0:17:22.480 --> 0:17:25.920 bacteria accepting these saying all right, now we know who 0:17:25.960 --> 0:17:27.920 else is out there, but we're not gonna say anything. 0:17:28.320 --> 0:17:32.240 We're we're only going to communicate using our own specific language, 0:17:32.440 --> 0:17:35.880 and that way we can prepare and unleash the dogs 0:17:35.880 --> 0:17:38.080 of war one and we can trick them into calming 0:17:38.119 --> 0:17:41.959 down for a while. Really, So there's also microbial disinformation 0:17:42.440 --> 0:17:44.560 sort of. It's really more of a decision about whether 0:17:44.640 --> 0:17:47.399 to communicate or not, right, the idea being like do 0:17:47.440 --> 0:17:50.280 you reveal that you are there, or do you keep 0:17:50.280 --> 0:17:52.679 its secrets so that you can build up your resources 0:17:52.680 --> 0:17:55.960 to a point where you then switch it on and attack. Um, 0:17:56.200 --> 0:17:58.359 keep in mind, like there are a lot of bacteria 0:17:58.400 --> 0:18:01.199 that are very much protective of a host, and then 0:18:01.200 --> 0:18:03.160 there are other bacteria that can be very harmful. So 0:18:04.200 --> 0:18:07.600 it behooves the harmful bacteria to kind of keep things 0:18:07.680 --> 0:18:12.520 on the quiet before going you know, ballistic, right, to 0:18:12.640 --> 0:18:15.640 have enough of a population to really do what it's 0:18:15.640 --> 0:18:19.160 intending to do before the host's immune system can figure 0:18:19.160 --> 0:18:22.600 it out. Right, right, So, uh yeah, we've already kind 0:18:22.600 --> 0:18:25.480 of talked about some of these different genetic expressions. There 0:18:25.480 --> 0:18:29.720 are also cases where the population density actually informs the 0:18:29.760 --> 0:18:33.919 bacteria to turn off expression. One of these is in 0:18:34.320 --> 0:18:39.280 cholera cholera, if the population gets too dense, then essentially 0:18:39.359 --> 0:18:41.600 the message goes out to hey, guys, let's calm it 0:18:41.640 --> 0:18:43.920 down a little bit. We're going to kill this guy. Yeah, 0:18:43.960 --> 0:18:46.960 and we want to be able to uh, to spread 0:18:47.200 --> 0:18:50.400 this as much as possible. That's our purpose. But if 0:18:50.440 --> 0:18:54.400 we go crazy, then the host may die as a result, 0:18:54.560 --> 0:18:58.320 or when in the case of cholera, the victim may 0:18:58.480 --> 0:19:03.280 end up experience experience seeing severe diarrhea, which then pretty 0:19:03.359 --> 0:19:06.480 much pushes out tons of the bacteria as a result. 0:19:07.000 --> 0:19:10.879 So it all depends upon the actual bacteria and what 0:19:11.200 --> 0:19:14.480 its quote unquote goals are, like what what its survival 0:19:14.520 --> 0:19:18.320 strategy is, and that determines whether or not it's turning 0:19:18.480 --> 0:19:20.840 on a gene once it hits a certain density or 0:19:20.880 --> 0:19:23.920 turning off a gene once it hits a certain density. Right, 0:19:24.040 --> 0:19:27.840 So there are lots of different research teams studying quorum 0:19:27.840 --> 0:19:30.680 sensing and looking for ways to either disrupt it or 0:19:30.760 --> 0:19:34.080 artificially stimulate it. So they're looking into the chemicals and 0:19:34.119 --> 0:19:36.639 the enzymes that are used in the process, plus the 0:19:36.680 --> 0:19:42.120 mechanisms that the bacteria have for creating and detecting these signals. Yeah, 0:19:42.119 --> 0:19:45.040 and I guess that leads us to the article that 0:19:45.520 --> 0:19:47.159 made us want to talk about this today. It was 0:19:47.160 --> 0:19:52.159 an interesting article in Scientific American from August about what 0:19:52.160 --> 0:19:57.120 what they called molecular tweeting in the study of bacterial communication. 0:19:57.160 --> 0:20:04.760 Now this doesn't mean bacteria literally using Twitter are not characters. No, 0:20:04.880 --> 0:20:08.200 But I wonder I can't come up with a good 0:20:08.440 --> 0:20:10.560 joke there. I do wonder. I do wonder if they 0:20:10.560 --> 0:20:13.560 occasionally attempt to tweet out a pizza slice and hopes 0:20:13.640 --> 0:20:19.960 that Dominoes will deliver to them. Yeah, you haven't seen 0:20:20.000 --> 0:20:23.080 those commercials. Yeah, that's a new thing where you can 0:20:23.119 --> 0:20:26.800 tweet out a emoji of a pizza slice and you 0:20:26.880 --> 0:20:29.800 order yourself a pizza. But what if it's not the 0:20:29.880 --> 0:20:31.880 kind of pizza you want? I think you. I think 0:20:31.920 --> 0:20:34.480 you set up a profile to say what type of 0:20:34.480 --> 0:20:40.000 pizza you want? Whenever you send that it's not gluten free. Yeah, 0:20:40.080 --> 0:20:45.280 so this is a new bit of research about bacterial communications. 0:20:45.280 --> 0:20:47.960 So it was a team of researchers at Carnegie Mellon 0:20:48.080 --> 0:20:53.280 University led by the engineering professor du Marculiske, and they 0:20:53.320 --> 0:20:55.919 wanted to use Twitter as a model to sort of 0:20:55.960 --> 0:21:02.000 help us visualize or understand different hypes of bacterial communication, 0:21:02.080 --> 0:21:06.359 how bacteria communicate with each other to form antibiotic resistant 0:21:06.480 --> 0:21:10.240 superstructures called biofilms. Yeah, this is interesting to me because 0:21:10.560 --> 0:21:13.880 it's when you might ask why Twitter. But if you've 0:21:13.920 --> 0:21:16.800 ever if you ever noticed something, when something begins to 0:21:16.840 --> 0:21:20.040 trend on Twitter, it's hit a certain density, like a 0:21:20.119 --> 0:21:23.840 pop culture density within Twitter itself, And that's kind of 0:21:23.840 --> 0:21:28.480 what they were comparing the behavior of bacteria too. That 0:21:28.920 --> 0:21:32.080 if you have enough people sending out this one little message, 0:21:32.080 --> 0:21:35.120 whether it's a hashtag or whatever, and then it catches on, 0:21:35.400 --> 0:21:38.359 that could be similar to the way a bacterial UH 0:21:38.600 --> 0:21:41.320 community sends out these messages to the point where it 0:21:41.440 --> 0:21:45.560 hits that population density. Yeah, it's a really clever metaphor. 0:21:45.680 --> 0:21:48.800 And also it is completely scientifically factual that people on 0:21:48.840 --> 0:21:54.520 Twitter will form UH slimy yet protective surfaces against which 0:21:54.880 --> 0:21:59.639 the greater population is protective. I've been there, I've seen it. 0:22:00.000 --> 0:22:02.639 We should talk about what these surfaces are. What are 0:22:02.680 --> 0:22:06.320 you're actually referring to. So large numbers of bacteria can 0:22:06.440 --> 0:22:10.800 communicate with one another to work together to form biofilm 0:22:10.920 --> 0:22:15.440 that protects them from threats. So a bacterium floating along 0:22:15.520 --> 0:22:18.360 individually in water is something we would refer to as 0:22:18.520 --> 0:22:21.960 plank tonic. That's plank tonic bacteria. You can think of 0:22:21.960 --> 0:22:24.359 it kind of like plankton in the ocean, is little 0:22:24.400 --> 0:22:29.199 bits floating along by themselves. They're free swimming. But biofilms 0:22:29.200 --> 0:22:33.520 are structures that are created when microorganisms like bacteria fix 0:22:33.600 --> 0:22:38.000 themselves down to a surface and they form dense conglomerations. 0:22:38.480 --> 0:22:42.120 So instead of using resources to build structures like flagella 0:22:42.280 --> 0:22:47.040 that help them swim along, they divert those resources and 0:22:47.080 --> 0:22:51.960 instead use them to build extracellular matrix, which is a 0:22:52.040 --> 0:22:56.560 kind of slime or polymer film that forms a protective 0:22:56.640 --> 0:23:00.840 structure around the bacteria. And these large back sterial films 0:23:00.880 --> 0:23:04.119 might be thought of as a kind of multicellular organism 0:23:04.240 --> 0:23:11.600 made out of former single celled organisms. Yeah, it's pretty gross. Especially, yeah, 0:23:11.760 --> 0:23:15.199 it's gross because they can form inside your body. Bacterial 0:23:15.240 --> 0:23:17.679 films can be really bad first because they have tougher 0:23:17.720 --> 0:23:20.520 defenses and they can linger inside the body for a 0:23:20.560 --> 0:23:23.840 long time and cause chronic infections. They're much more resistant 0:23:23.920 --> 0:23:28.800 to your to your immune system, and to antibiotics because 0:23:28.800 --> 0:23:32.400 of these protective structures and matrices that they form. Yeah, 0:23:32.600 --> 0:23:35.280 it's sort of like going back to Star Trek, going 0:23:35.359 --> 0:23:38.520 like like divertal power to the forward shields and then 0:23:38.800 --> 0:23:41.439 you know, yeah, it's a community of a power grid 0:23:41.760 --> 0:23:45.720 adding to a single point of of shielding. Right, But 0:23:45.960 --> 0:23:51.560 how do brainless, single cell little critters decide to do this, Like, 0:23:51.600 --> 0:23:54.720 how do they figure out when they can form a 0:23:55.200 --> 0:23:58.720 biofilm instead of and how that will help? Yeah, So 0:23:58.760 --> 0:24:01.480 the CMU researchers that we're referred to in this Scientific 0:24:01.520 --> 0:24:05.520 American article started by observing bacteria in the process of 0:24:05.560 --> 0:24:09.360 coming together to form biofilms. So they got some bacteria, 0:24:09.760 --> 0:24:12.600 set them to work, and observed what they did. And 0:24:12.640 --> 0:24:16.040 they were trying to observe the specific conditions under which 0:24:16.080 --> 0:24:20.120 biofilm growth takes place. And then they use that information 0:24:20.240 --> 0:24:23.600 to make some software that could simulate the behavior of 0:24:23.640 --> 0:24:27.680 bacteria undergoing biofilm growth. And this is the real outcome 0:24:27.720 --> 0:24:30.040 of this study is the idea is the idea that 0:24:30.040 --> 0:24:35.040 we can create simulations of how bacteria communicate with one 0:24:35.080 --> 0:24:38.880 another under these circumstances, which can help us learn how 0:24:38.920 --> 0:24:42.480 to defeat them once and for all. Yeah, I mean 0:24:42.920 --> 0:24:45.960 even if you could just uh, because we've talked about 0:24:46.240 --> 0:24:51.720 or or rather, scientists have talked about either replacing or 0:24:51.840 --> 0:24:56.240 or restricting communication among bacteria as a means to keep 0:24:56.280 --> 0:24:59.199 them from being able to form these defensive measures or 0:24:59.280 --> 0:25:05.199 to uh delay virulence or or not anys genesis. That 0:25:05.320 --> 0:25:08.040 the idea that if we can mess up their communication lines, 0:25:08.560 --> 0:25:12.080 then they'll never know that they're at the stage where 0:25:12.080 --> 0:25:16.159