Proof of concept 2 — red-light control and the “trash collector” insight

34:58they're very close to that black >> molecule. So, they're right next door. >> And just those two changes made the entire protein sensitive to that intermediate quantum >> level that green light triggers. And now on the left, you can see now the the yeast is growing. >> Yeah. Yeah. Yeah. >> Using those >> Yeah. Yeah. >> changes. >> Oh, God. >> Right. And this this is what's kind of interesting here is again you you you come up with the plan, you try it and then you find out oh actually there's this thing that we didn't understand which is this intermediate stage that exists >> and if your fundamentals are good then you can then continue the process

35:40because then you're like okay well now if we manipulate these intermediate stages >> we should still be able to get the results we're looking for. >> Exactly. And now now we have a whole new >> EL222 star I guess >> that is allowing for orthogonal color multiplexing. Right. Now I can have green light. Now I can have blue light. Blue light on green light off or vice versa. >> Right. >> Cuz because the the combination of the two it is is it its own. >> Yeah. Now I can now I can >> control a bunch of genes. Imagine if I could do this over and over again, right? If I keep doing the directed evolution such that the bandwidth of the response on that protein is really narrow. So green light of this

36:21particular frequency is only going to trigger that protein, right? >> Green light of this other, you know, teal versus aquamarine is going to trigger some other thing, right? >> Mhm. >> Cuz with lasers, we can get really really narrow bandwidth. We can be like it is at exactly 450. It's not 451. It's not 452. It is 450 nanometers. Right? So again, like for biomedical research, this is huge. It's allowing multipplexing of genomes. >> Yeah. >> Right. Of gene turning on and off. >> Yeah. Yeah. Yeah. Yeah. And and and to maybe distill it down to kind of a basic concept level, we're creating a controller

37:02for researchers to better drive the process, the research processes they want to around protein synthesis. Is that the right Yeah. And gene expression. >> And gene expression. >> That's the big one. Yeah. Okay. >> Yeah. And protein synthesis is gene expression. >> What is what the drive it's the thing that drives the gene expression. >> Yeah. Exactly. >> Okay. >> Okay. So, breakthrough number two. >> Okay. >> Has to do with trying to use it with red light. Now, with red light and infrared light, you can't use the EL22 because red light is way far. You know, red light is at what, like 800, 700 nanometers, whereas this thing was at 450. So, it's like almost half the energy, >> right? Um, so you don't have any hope in using the same protein. You're going to

37:43use something else called the 5B PIFF3 system. Okay? This is something that uses 660 nanometers to turn on and 740 nanometers to turn off. Okay. >> Why would you want to use red light? Well, red light is very good for deep tissue penetration. >> Yes, >> it's the same reason why sunsets are red. >> Okay? the sunset is red and the sky is blue because blue light scatters more because of rally scattering. And so that's why from every direction in the sky you're getting blue light because the sun is illuminating it with all the colors. But really the shorter frequencies are the ones that are sorry the the shorter wavelengths the higher frequencies are the ones that are coming to us from all different angles. But

38:23when the sun is setting >> it has to go through a lot of atmosphere. So for the same reason all the shorter wavelengths higher frequencies are getting scattered away from us and the red light is penetrating through. Same thing happens in tissues in biological tissue. If I want to do this kind of you know light directed turning on and turning off of genetic factors and things like that in my biomed research but deeper in the tissue the blue light is only going to get through so much. If I use red light or infrared light that's going to get deeper into the tissue. And so it's very much to my advantage. >> Have you uh seen the uh speaking of red light? Yeah. And getting deeper into the

39:04tissue, the the new masks that have been created in sort of the >> I guess uh beauty and skinare and they're blaring red light at your face >> because it gets deeper into >> deeper into the tissue. Yeah. >> I'm I'm just same thing. >> Same thing. Exactly. Now these these these proteins just like the EL222 that we were discussing with the blue light these all rely on a chromophore which is some kind of molecule that is going to absorb the light that's going to get triggered into a high energy state and then the protein around it is going to be sensitive to that high energy state and then change its configuration and become active. The particular

39:45chromophore here is fico cyanobilin PCB. This thing is hella expensive. Okay. Um a,000 it's $1,400 per two mg. It's also highly unstable and it's not natively produced in yeast and mammals, right? So in order to actually express it in yeast, I have to give it this >> chromophore and I have to give it the red light. It's just it's just really expensive and it's got to be like timely right? >> Because it degrades really fast. So the campaign that we want to do with this opto evolution is can we make this thing respond to red light without that chromophor >> without the like additional secondary piece that is required to actually make

40:26the process >> exactly without without PCB. >> Can we get the lobster tail without the caviar? >> Yes, that's exactly right. And so that's exactly what they did. They subjected these dashbog cells to red and far red pulsing and no external PCB. Mhm. >> There were mutants that had loss of function mutations that survived and created and were actually responsive to PCB, >> but >> they had deletions of this particular enzyme, this particular gene called Y1. >> Now, why Y1? Because that Y1 is basically a trash collector enzyme. >> Okay, >> that's weird. Why would a trash collector mezzy >> cause me to be now sensitive to the red

41:08light that I was no longer sensitive for? I don't have the chromophore that I need for the red light. But if the trash collector is not there, all of a sudden I can be responsive to red light. What What does that mean? That means the trash collector was collecting some other molecule that I was using. >> Yeah. Yeah. Yeah. Yeah. >> That I'm now using for the chromophore to be sensitive to red light. >> Right. Right. >> And now that the trash collector is gone, there's some random other molecule that I can now grab and use to be sensitive to red light. Yes. >> Isn't that cool? Yeah, that is very good. The the the trash collector uh was taking away the active ingredient that allowed the response to the red light. When you get rid of the trash collector, the active ingredients then available

41:48>> then available. And that's exactly what they found. They found this active ingredient bivverin >> BV and when you give the yeast cell artificial BV, >> it'll respond to the red light. If you take out the trash collector Y1 gene, it'll be responsive. >> It will also be responsive. >> It'll also be responsive. So now what does that mean? That means that I've the endogenous bilivin >> can actually trigger my red light receptor cells. All I have to do is delete the trash collector. >> Right. Right. >> Enzyme. >> And this this >> and now it's way cheaper. >> It's way cheaper. We This goes back to what this thing you brought up before and continue to bring up which is >> if we can use the body's natural system

42:29to drive the outcome we're looking for versus artificially inserting something, it is >> always better. I don't want to say always, but just in case. >> Yeah, just Yeah, you know what? Yeah, you're you're very correct. In biology, there is never an always. >> Generally speaking, Generally speaking, >> you're right. Yeah, I should. >> It's better. >> Most of the time. >> Most of the time. Yes. Yeah. But biology is a notorious.