Latest / From First Principles / Nobel Prize in Chemistry 2026 Explained: Mirror Molecules (EP 63)
Transcript
- 0:03A chemist in Paris and a chemist in Tokyo who cracked one of life's oddest habits.
- 0:10Look at your hands.
- 0:12Mirror images.
- 0:13But a left glove won't fit your right hand.
- 0:18Many molecules come in left and right versions too.
- 0:22One smells like spearmint.
- 0:24Its mirror twin smells like rye bread.
- 0:27But chemistry in a flask always makes both.
- 0:3050-50.
- 0:33In 1986, Henri Gagin found something odd.
- 0:38A catalyst that was only a little right-handed made products that were mostly right-handed.
- 0:45Picture six right-handers and four lefties on a dance floor.
- 0:50Each lefty pairs off with a right-hander and sits down.
- 0:54Who's still dancing?
- 0:56Only right-handers.
- 0:58Then, Kenzo Soai built a molecule that copies itself, hand and all, like a rumor that spreads.
- 1:07A head start of one molecule in two million became more than 99% in just three rounds.
- 1:16Life builds itself from just one hand.
- 1:19This is a clue to how that happened, and a sharper way to make medicines.
- 1:25And this is the 2026 Nobel Prize in Chemistry.
- 1:33Hello, Internet.
- 1:34This is your captain speaking, Lester Nare, joined as always by my co-host and our resident PhD, Krishna Chowdhury.
- 1:44We are on day three and our final day of Nobel Prize week.
- 1:50We are going to go from the search for ghostly particles in Antarctica to the winner of the chemistry Nobel Prize.
- 2:02And this one is interesting and it reminds me of one of my favorite episodes that we did at the end of last year.
- 2:10We have left and right hands.
- 2:13And similarly, there are left and right molecules.
- 2:17But life overwhelmingly prefers one specific thing.
- 2:22Today's prize is about how chemistry can make that asymmetry happen.
- 2:28It connects the way we make medicines to a much older question.
- 2:32Why did life settle on particular molecular building blocks in the first place?
- 2:39This is going to be interesting.
- 2:40As always, we are going to talk about the science from the ground up today, starting with who won.
- 2:49The 2026 Nobel Prize in Chemistry has been awarded to Henri B. Cagan of the former University Paris-Sud in France and Kenzo Soai of Tokyo University of Science in Japan.
- 3:05And the official citation is for the discovery of nonlinear effects and autocatalysis in asymmetric organic synthesis.
- 3:14Talk about a mouthful.
- 3:15Yeah.
- 3:16But by the end of the episode, we will have unpacked that statement.
- 3:20And there's a hint in the words nonlinear and asymmetric autocatalysis.
- 3:25For anyone familiar with biochemistry, this should immediately ring a bell because that's kind of what life is.
- 3:32Okay.
- 3:32It's a nonlinear phenomenon because, you know, reproduction happens.
- 3:37And if you've ever seen the bacterium sort of
- 3:41expand in a petri dish from one you get two to four to eight and there's this doubling factor so obviously that's non-linear and it's a kind of auto catalysis because it's a bunch of chemical reactions that make themselves right the dna makes more dna makes more dna obviously there are multiple steps in the process but at the end of the day life is non-linear and it is auto catalysis it's also asymmetric because of the kinds of molecules that life prefers
- 4:10Even though the molecules in life can exist in symmetric parts, life is remarkably consistent with which one it uses.
- 4:17DNA is a great example of this.
- 4:20DNA is right-handed, meaning if I were to put my thumb on the axis of a DNA molecule...
- 4:26The curve is always the way that my fingers wrap around.
- 4:29It's always going to go right-handed, sort of clockwise, if I were looking up the axis of DNA.
- 4:36But you can make DNA that is left-handed, right?
- 4:40It's just that life never does it.
- 4:42So the two Loretz contributions fit together here because Kagan showed that a small imbalance in a catalyst can produce a substantially greater imbalance in the product.
- 4:56more right-handed than left-handed, then you can make that nonlinear effect.
- 5:01And so I found a reaction in which the product becomes the catalyst for making more product.
- 5:06That's that autocatalysis part.
- 5:08Okay, so before we unpack the chemistry, what is the surprising part here?
- 5:13Why wouldn't a small advantage naturally just become a big advantage?
- 5:18Okay.
- 5:19Right.
- 5:19And that's actually what I was asking when I was researching this kind of stuff.
- 5:23It turns out that making more material and increasing its purity are two different achievements.
- 5:30So if you repeatedly double, let's say you've got a mixture of 51, 49, but the 51...
- 5:40of molecules start making their own version and the 49% make their own version, the ratio is going to remain exactly the same, right?
- 5:49So there's something in the chemistry that has to favor the majority disproportionately for the imbalance to grow.
- 5:56And that is what this Nobel Prize is about.
- 5:58That's the key distinction.
- 6:00It matters for making useful molecules, including pharmaceutical intermediates.
- 6:05It also gives us an experimental way to investigate molecules.
- 6:08the holy grail of biochemistry, which is how a world of molecules, an abiotic world,
- 6:16without a consistent handedness, could give rise to the life that we have on the planet Earth, which is all one particular handedness.
- 6:25So we've talked a lot about handedness, and it's not just an analogy.
- 6:33So what does it mean for a molecule to be left or right-handed?
- 6:37Yeah, we went into detail with our Yang Mills episode, but we'll do it again.
- 6:43So let's hold our hands...
- 6:46This is my left hand.
- 6:47This is my right hand.
- 6:49There is no transformation that I can do to my right hand, like rotating wise, that will give me my left hand.
- 6:57Even if I rotate it, right?
- 6:59Sure, they meet up to form like a prayer hand or a clap.
- 7:03But these are two separate things, right?
- 7:05Because in this case, the hand is facing me.
- 7:08The thumb is to the left.
- 7:09But the hand is facing me.
- 7:10My palm is facing me.
- 7:12And here the back of my hand is facing me.
- 7:14The front is facing the camera.
- 7:15So even though the thumb is pointing in the same direction, these are not the same, right?
- 7:21So it requires this 3D point of view to really understand this.
- 7:26And the chemistry world has a word for this.
- 7:29It's called chirality from the Greek word forehand.
- 7:33And so we would say that our hands are chiral.
- 7:36Okay.
- 7:36Now let's look at some of the building blocks of life itself.
- 7:40This is alanine.
- 7:41It's an amino acid.
- 7:42Sometimes you can buy it in a powder if you want to like get swole or whatever.
- 7:47Right.
- 7:47And on the left-hand side, we see the chemical diagram of this thing.
- 7:52There's a carbon at the center.
- 7:54It's an amino acid, so it's got an amine group, an NH2 to its left, a carboxyl group to its right.
- 7:59That's a COOH.
- 8:01And then the R group, which is the thing that changes for every single amino acid.
- 8:06In this case, it's just a methyl group, CH3.
- 8:09If you look at that diagram itself, you don't find anything funny.
- 8:12But if you look at the 3D picture...
- 8:16You find that there are two versions.
- 8:18There's the left-handed alumine and the right-handed alumine, which in chemistry they call D-alamine.
- 8:24L-alamine is the left-hand version.
- 8:27And these are chiral molecules because just with our hand, there's no way to rotate one hand to make it the other.
- 8:36There's no way to rotate...
- 8:38the right-handed enantiomer, which is the right-handed version of this molecule, to make it the left.
- 8:44It's the same atoms.
- 8:46It's the same bonds even, right?
- 8:47The carbons are bonded to the oxygen in exactly the same way and the nitrogen in exactly the same way.
- 8:54But in one case, the oxygen is coming out of the page, and in the other case, the oxygen is going into the page.
- 9:00Just like how our hands, in one case, the palm is facing me, but in the other case, the back of my hand is facing me.
- 9:09This is what we talk about when we're talking about mirror image molecules and why they're chemically alike in some environments
- 9:17In other environments, you can actually distinguish them.
- 9:20And that last detail is what matters.
- 9:22If you look at the left-hand side, the flat diagram does not give you the information.
- 9:26You need the 3D information to distinguish between the left and the right-handed version.
- 9:33Now, not everything in life is chiral.
- 9:35You can have achiral molecules.
- 9:37For example, there is...
- 9:39The glycerol molecule, which is just carbons with a bunch of OH groups attached, that is achiral.
- 9:45If I take a mirror image of that, it's the same.
- 9:49Fatty acids like betyric acid, again, if I take a mirror image of that, it's going to be exactly the same.
- 9:56Glucose, on the other hand, is chiral.
- 9:58So it's ribose.
- 9:59That's why actually DNA and RNA have a particular handedness,
- 10:09We only use a particular handedness, and that's what causes the spiral.
- 10:12Deoxyribose, again, has a particular handedness, in this case right-handed, which is why DNA is right-handed.
- 10:19So in biology, you have a mixture of both.
- 10:23But this has crucial implications for biochemistry in general.
- 10:29Because imagine trying to fit a right-handed organism.
- 10:33glove into your left hand it's just not going to work right and this has implications in biochemistry because the glove you can imagine is an enzyme that has a particular handedness and it is expecting the same handedness of whatever thing that it's going to bind to right if you give it the other handedness
- 10:55Things are going to get funny.
- 10:58One of the big implications of this is, for example, the left-handed carvone, which is the odor that we get from spearmint, right?
- 11:07We've got a photo of that where we show the left-handed version of carvone is how we get spearmint.
- 11:15That's the odor that we get from, you know, when we smell mint.
- 11:19The right-handed version of the same molecule,
- 11:25get confused.
- 11:26They start smelling something completely different.
- 11:29It's the odor of caraway.
- 11:31The same chemistry...
- 11:33The same, I shouldn't say the same chemistry.
- 11:35The chemists will get mad.
- 11:37The same atoms, the same arrangement of atoms, but in the 3D world, they look entirely different because they are mirror images.
- 11:46And that has an effect on how we actually sense this molecule.
- 11:51And so these two forms, they differ in activity, metabolism, side effects.
- 11:56Sometimes both are useful, sometimes not.
- 11:59And the point is that their behavior is,
- 12:01can be measured, and you can infer it by looking at their activity.
- 12:05This is incredible.
- 12:07And so I think the next natural question here, now that we kind of understand this idea of handedness, especially that you can look at a 2D diagram versus a 3D diagram, and there's different implications based on how you're looking at it.
- 12:20How did we, in chemistry, even get to the point where we discovered this idea of left and right-handedness?
- 12:27Yeah.
- 12:27Yeah, I mean, the Nobel Prize in Chemistry in this year, 2026, the results form from a long chain of ideas, as is classic in all of science.
- 12:38And the first result really goes back to the mid-19th century.
- 12:41It all began with Louis Pasteur.
- 12:43He was investigating a substance that is important for wine production—
- 12:47We all like wine here in California.
- 12:50He was investigating tartaric acid.
- 12:53He was French, so obviously they're obsessed with wines.
- 12:57Let me just say, it's been shown in international competitions that California wines are better than French wines.
- 13:05I heard he's from the French region of Tartaria.
- 13:09Is that a thing?
- 13:10No, it should be.
- 13:12But in any case, tartaric acid is the stuff that you might recognize
- 13:17from wine diamonds.
- 13:18This is the particulates that kind of settle at the bottom of a glass, or sometimes they form in the cork, as you see on the upper right-hand side.
- 13:27These are little crystals of potassium bipartite, and they...
- 13:33take on the form, they take on the color of whatever wine is in there.
- 13:37They're harmless, and sometimes they're actually manufactured in wine barrels, because they'll settle at the bottom, right?
- 13:45Now, Louis Pasteur heard about tartaric acid, and his colleagues said that sometimes they bent polarized light to the right, and sometimes...
- 13:54the crystals bent polarized light to the left.
- 13:58And that really piqued his interest.
- 14:00So he grew crystals of tartaric acid and examined them under a microscope.
- 14:05And he discovered they exist in two different variants.
- 14:10On the left-hand side, we actually see some of the drawings that he made of these crystals.
- 14:14And you can see they're mirror images of one another.
- 14:16So the crystals themselves came in these two different forms.
- 14:20And one of the geniuses of Louis Pasteur is to look under the microscope and notice that difference.
- 14:28Under a microscope, it's very easy to be like, oh, they're the same crystal.
- 14:32But the mind of Louis Pasteur, the genius that he was, he noticed that subtle difference that actually...
- 14:39If you arrange them, because like in the drawing, they come out in this nice arrangement, right?
- 14:44But that's because he's drawing it that way.
- 14:46Presumably on the Petri dish where he's looking under the microscope, there are all these different arrangements.
- 14:51And he was able to notice, right, with a light microscope that there are these two versions.
- 14:56And there we have actually the Louis Pasteur Institute still has little vials of the bipartite vials.
- 15:03that he made in these vials, which is absolutely incredible, right?
- 15:07So he discovered that there's these two variants, each that are mirror images, and then using little tweezers, he separated out samples of one-handedness and samples of another-handedness.
- 15:19But this is at the aggregate crystal level, okay?
- 15:22Now, from that aggregate crystal, he dissolved each thing in liquids, and he found that one of them bent light to the right,
- 15:32and the other one bent light to the left.
- 15:33This is a classic experiment that we see in, like, when we talk about chirality and molecules that are chiral.
- 15:40What you do is you have a light source that brings out unpolarized light, unpolarized light meaning the electric field of your light wave is in every direction.
- 15:49You put that through a polarizer, which is like the stuff, you know, the sunglasses that we have with the polarized sunglasses.
- 15:56That's literally a polarizing filter that selects for a particular
- 16:00orientation of electromagnetic field.
- 16:03Like the light is, you know, oscillating in all these different directions and the polarizer preferentially selects one particular orientation.
- 16:11So now that you have polarized light that's gone through this set of glasses, you're going to see
- 16:15you put that through your sample, which is a dissolved liquid that has either the left-hand side version of the crystal or the right-hand side version of the crystal.
- 16:24And what he noticed was the axis of polarization would rotate as the light propagated through the medium.
- 16:32And you can tell that by putting another polarizer on the right-hand side and seeing how much comes out.
- 16:37Depending on the angle, you would get...
- 16:40a lot of absorption or not absorption at all.
- 16:42This is interesting.
- 16:43It's both kind of like a control mechanism on the left-hand side as the polarizer and then like a sensor on the right-hand side as an analyzer.
- 16:50Exactly.
- 16:50And this is a classic experiment now that we use in a lot of chemistry labs.
- 16:55The striking part is that the distinction between the left and right crystals survived dissolving stuff into the liquid and then putting it into this polarizer.
- 17:06Okay?
- 17:06So that's telling you that the things that make up the crystal
- 17:10have that property of left and right handedness.
- 17:13This was the key observation.
- 17:14It's not an artifact of the experimental setup.
- 17:16Yeah, yeah, yeah.
- 17:17It's not like the crystal is growing in some weird, you know, like the left hand side of the Petri dish has some temperature and the right hand side.
- 17:23No, it's like literally the things that make up
- 17:26this crystal are left and right-handed, right?
- 17:30And this property matters because when it came to these tartaric crystal molecules, the next experiment that he did was whether bacteria preferred one or the other.
- 17:40And he saw that indeed they did.
- 17:42This was in 1857.
- 17:43He investigated what happened if bacteria fermented on tartaric acid
- 17:49preferred, you know, growth on one medium versus the other.
- 17:52He saw that bacteria willingly fermented.
- 17:55The bacteria were great at eating one particular type of tartaric acid.
- 18:02This is the same type that was found in grapes and found in wine bottles.
- 18:05But the other type, they did not eat at all.
- 18:09The bacteria did not grow at all.
- 18:10And this is the first indication that life's chemistry is somehow chiral.
- 18:16So Pasteur kind of started this process by separating these different types of crystals, which are at a macro size level, because they had some differences in it.
- 18:26But the thing he really discovered was this underlying property of what would have been at the time these invisible molecules.
- 18:33Yes, exactly.
- 18:34And at that point –
- 18:36Atomic theory was new.
- 18:37Like, there wasn't really a sense of, like, atoms and molecules in the sense that we now take for granted, right?
- 18:43But that was the key conceptual leap.
- 18:45And later, when researchers began studying life's building blocks, they discovered that naturally occurring amino acids all bend polarized light to the left.
- 18:54So all of the naturally occurring amino acids, you dissolve them into a solution, the polarized light always bends towards the left.
- 19:01And this is where we get left-handed amino acids like L-alanine that we were talking about earlier, leucine, valine, every single amino acid that is chiral
- 19:10Life uses only a particular type of chirality, and that's why we call life homochirality, because homo is the same, chirality meaning this handedness.
- 19:21Subsequent experiments in sugars found that DNA helix is the opposite.
- 19:25It's actually right-handed, and the sugars are actually right-handed.
- 19:29And that's because the glove kind of fits the, you know, the enzymes fit the right-handed version, things like that.
- 19:35And this insight is pretty incredible, right?
- 19:39And the next question, obviously, is what happened at the dawn of life to make life's chemistry one-handed?
- 19:45Because Pasteur was able to create both versions in his lab, right?
- 19:49If you grow tartaric acid abiotically, you'll get both versions of the crystal.
- 19:54But everywhere that we see in life, they prefer only one-handedness.
- 19:58And when we try to figure that out, the main question is, why do living organisms only use one mirror image of the amino acids?
- 20:07Like, how can this preference even arise?
- 20:11Now, some chemists just claim that chiral chemistry is unique to life, right?
- 20:15Maybe it could be that, like, there's, like, you know, some woo-woo thing.
- 20:20Hand-wavy.
- 20:20Yeah, hand-wavy woo-woo thing of, like, vitalism, where, like, life has some, like, force, right?
- 20:27Right.
- 20:28is beyond the laws of physics as of now that we haven't seen.
- 20:32But in the 1900s, a German chemist, Willy Markwald, he showed that, no, I can actually make a reaction that prefers one way or the other.
- 20:42This is the first time that we've found a reaction like this.
- 20:46He used a catalyst.
- 20:48A catalyst is basically an intermediary in a chemical reaction that facilitates a chemical reaction.
- 20:55He figured out that actually if the catalyst itself has a particular handedness, then it will prefer to make products of that same handedness versus the other handedness.
- 21:07Well, sometimes the other way around.
- 21:08But in any case...
- 21:10You've got two different products that you can make, the left and the right-handed version.
- 21:13If the thing that is making the product is itself right or left-handed, then you can skew the chances one way or the other, right?
- 21:23And this particular experiment here, this is from the Nobel Committee, the visualizations that they put out.
- 21:32Here, the key thing is you've got a metal ion that is marked M in black that is associated with a chiral molecule, and then that thing attaches to a substrate, and that entire complex starts creating one particular side of products versus the other.
- 21:52Now, in this case, both are being created, but one is preferred over the other.
- 21:57In physical terms, what this really means is that both pathways...
- 22:01have different activation energies.
- 22:04We've got a little diagram that kind of shows this, where if we talk about reaction progress on the x-axis...
- 22:12Okay.
- 22:13That means going from reactants to products.
- 22:16You can think about it as a time axis.
- 22:17It's not exactly, but let's just say for this visual, it's a time axis.
- 22:22The Gibbs free energy is on the y-axis.
- 22:25That tells you effectively what is the energy of the chemicals that are involved here.
- 22:32The reactants have a higher energy and the products have a lower energy.
- 22:35That's why, just like in physics, you go from high to low energy.
- 22:38But in order to get there, you have to go through this hill, which is the activation energy.
- 22:41That's why, just like in physics, you go from high to low energy.
- 22:42That's why every time you put reactants into a vial, they're not going to immediately go to products.
- 22:49A lot of times they're going to stay reactants because you have this energy barrier.
- 22:53when I put my Mentos into my Coca-Cola, it doesn't immediately explode.
- 22:57There's a little buffer time.
- 22:58There's a little buffer time.
- 23:00And that's because, you know, the jiggling is getting over that activation energy.
- 23:05But as you know, the stuff is a runaway reaction because the jiggling creates higher temperature, which then creates more jiggling, which creates more jiggling.
- 23:13And so more and more stuff go over the activation energy.
- 23:16What's happening with the chiral catalyst is that the activation energy is decreased
- 23:22For the ones that are preferred, like let's say the right-hand side has a lower activation than the left-hand side because the catalyst is preferring that one over the other.
- 23:30And that's why there's more right-hand side reactants or products, I should say, versus the other.
- 23:35There's more right-hand side products versus the other because the activation energy is lowered because that catalyst itself...
- 23:42is right or left-handed.
- 23:44Depending on its handedness of the catalyst, the entry point for the end product of that same handedness has a lower barrier to entry.
- 23:52Exactly.
- 23:53And this was in the early 1900s.
- 23:55The difference was small, but the mere existence of it is revolutionary because this means that it's not just life.
- 24:01We can create organic stuff in our Petri dish, in our vial,
- 24:09That creates this asymmetry.
- 24:11So there's the potential.
- 24:13You're saying there's a chance.
- 24:14Yes.
- 24:14The woo-woo.
- 24:15It's not the vitality.
- 24:17Yeah.
- 24:17And there's a way to fundamentally understand what life is doing to make it homochiral.
- 24:24Like this is now where we are like, okay, there's a path that we can go down.
- 24:28Exactly.
- 24:29To understand that fundamental question.
- 24:30Exactly.
- 24:31And this is where the theoretical physicists come in.
- 24:33Oh, yes.
- 24:33Right?
- 24:35This brings us to 1953.
- 24:36Yeah.
- 24:37There's an article by Charles Frank from the University of Bristol.
- 24:43I should say Sir Charles Frank because he was knighted.
- 24:45He's a fellow of the Royal Society.
- 24:47And he is a theoretical physicist who...
- 24:51A colleague describes to him the fact that chemistry and chemists can't really understand why life's asymmetry arose.
- 24:58And maybe a mathematical solution or like at least a roadmap to understanding this problem would be nice.
- 25:05And so Charles Frank writes this paper and it's kind of a –
- 25:10It's a classic theoretical physicist paper of like, this is trivial.
- 25:15He's the kind of theoretical physicist that everyone hates, especially the experimentalist.
- 25:20Okay.
- 25:21Like in his introduction, he talks about how like, you know, this is...
- 25:29This is... Guys.
- 25:30Why are you wasting my time?
- 25:31Yeah, yeah.
- 25:32And he responds with three categories that we need to establish in order to make something like an asymmetry like this happen.
- 25:40The first one is that there is a chiral catalyst and an asymmetric reaction.
- 25:44That's the kind that we had just discussed from Willy Markwald.
- 25:51The second stipulation...
- 25:54is that the formation of one of the mirror images is somehow enhanced and the other is dampened.
- 26:00This means that there's an inhibition of types.
- 26:04Okay, you're not just making both.
- 26:05Somehow the presence of one is making the other one worse.
- 26:09Okay?
- 26:09And the third is that the chemical reaction has to form the catalyst itself.
- 26:14You need a runaway reaction.
- 26:16You need the product itself to go back into the reaction.
- 26:19and feed in, so you get this nonlinear effect.
- 26:21So he's putting out a roadmap, okay?
- 26:24That last part is called autocatalysis, and that's the self-reinforcing effect.
- 26:29And Frank concludes his report by just laconically noting that a laboratory demonstration may not be impossible.
- 26:37Like, really?
- 26:39Yeah.
- 26:39This is something that classic theoretical physicists do.
- 26:43It's like, oh, why don't you just figure it out?
- 26:46Just go do it.
- 26:47Yeah.
- 26:47Like, what are you asking me for?
- 26:48Yeah.
- 26:49It's like, oh, really?
- 26:50Okay, nice.
- 26:52Well, his paper does make waves because now we've got kind of a roadmap on how to get there, right?
- 26:58And it's spread widely among chemists.
- 27:00It becomes kind of a chemical puzzle that university lecturers present to their students.
- 27:05Like, this is an open problem.
- 27:06Let's see if you guys can figure it out.
- 27:08Now, Markwald, as I said, had already succeeded in the first condition at the start of the 20th century.
- 27:13And autocatalysis, asymmetric catalysis, is also something that has been figured out.
- 27:21The 2001 Nobel Prize in Chemistry recognized William Knowles, Ryoji Noyori, and Barry Sharpless for important chiral catalytic reactions.
- 27:31This is the autocatalysis that we're talking about.
- 27:36That led to the industrial route to L-DOPA, which is a pharmaceutical that's used pretty widely.
- 27:43And in 2021, the Nobel Prize recognized Benjamin List and our favorite chemist on the podcast, David McMillan from Princeton University.
- 27:53Go Tigers.
- 27:54They created asymmetric organocatalysis.
- 27:58So organic chemistry that preferred one way or the other, right?
- 28:03Yeah.
- 28:05All of that is fine.
- 28:06The Nobel Prize in Chemistry this year recognizes the fulfillment of the remaining two conditions, meaning you need inhibition and you need that inhibition paired with catalysis, this runaway reaction.
- 28:20Okay?
- 28:21So in nature, there's this 50-50 thing where it happens naturally where it's not asymmetric.
- 28:27And through 2021, we had all of these different ways to artificially create an asymmetry.
- 28:34But the thing was to fulfill sort of the ultimate vision, we still had two missing variables.
- 28:43Yeah.
- 28:44And those specifically are the difference between the past Nobel Prizes and this Nobel Prize.
- 28:48Exactly.
- 28:49In this particular Nobel Prize, we are establishing the nonlinear effect, which is this sort of property that like –
- 28:56I can get more asymmetry from underlying asymmetry and the fact that we can have a runaway reaction, that autocatalysis part.
- 29:04Okay?
- 29:06So to make that question measurable, there's one scientific sort of...
- 29:14There's one scientific, like...
- 29:17parameter that I need to introduce to everyone.
- 29:20And this is the idea of enantiomeric excess, abbreviated EE.
- 29:25This is the difference between the amount of left-handed stuff and the amount of right-handed stuff.
- 29:30If I have exactly 50% left and right, that's a 0% excess, right?
- 29:35Because I have exactly the same.
- 29:37If I have all of 1%,
- 29:40all of one type, if I have all of left-handed and no right-handed, that means I have 100% excess of left-handed stuff.
- 29:49This is a key thing, a key parameter that we're going to have to deal with as we move on.
- 29:54So a 50-50% mixture, that's a zero.
- 29:57If I have a 60-40 mixture, that's a 20% excess, because it's really the difference between how much of one I have and how much of the other I have.
- 30:07And that distinction is essential as we get to talking about how a small starting imbalance is going to create a large ending imbalance.
- 30:16So 2% excess is almost a coin flip?
- 30:20Yeah.
- 30:20And then 51, 49 of the other... That's 2%, right?
- 30:25That's 2%.
- 30:25Yeah, and that's almost a coin flip.
- 30:27Okay, okay, okay, okay, okay.
- 30:28Yeah.
- 30:30So I think we now are getting to...
- 30:34Our Nobel laureates.
- 30:36Yes.
- 30:36We know the setup.
- 30:39And, you know, as a fan of Thierry Henry, the French footballer, although he was an Arsenal player, this is a Chelsea house.
- 30:47We will start with Henri Cagin.
- 30:51And so what was it that he discovered as a part of now this setup we've created?
- 30:57Right.
- 30:57So now we get to our actual Nobel laureates.
- 31:01Henri Cagón tries to tackle the nonlinear part of the Nobel description.
- 31:07Let's suppose that we start with a pure right-handed catalyst that favors right-handed products.
- 31:13Mark Wald has already shown that.
- 31:15If you start with the catalyst itself has a particular geometry, then the products are going to favor some particular geometry.
- 31:22Okay, so let's say the right-handed catalyst favors the right-handed product and the left-handed catalyst favors the left-handed product.
- 31:30The prevailing wisdom at the time was that if each of these catalysts work independently, then if I start out with, let's say, a 60-40 mixture of catalysts, the ending reactants are also going to be 60-40, because 60% of the catalysts created the 60% products, the 40% of the right-handed stuff created the 40%, and the ratio is going to remain the same, right?
- 31:55The slope, in this case, is going to be one.
- 31:58Like, if I start out with some
- 32:00I'm going to end up with some ratio.
- 32:02The slope could also be something different.
- 32:04For example, like, you know, if I start out with 60%, I could end up with 30% of something.
- 32:09But the line is going to be linear.
- 32:12Because maybe, like, you know, there's some, like, weird effect that happens.
- 32:15And, like, one type goes one way and the other type goes the other way.
- 32:20The line, if I increase the asymmetry on the catalyst side, I will just only linearly increase the asymmetry on the reactant side.
- 32:29Because these things are working independently.
- 32:31Right.
- 32:32Okay?
- 32:33That is the assumption that Kagan starts to question.
- 32:37Okay.
- 32:37Everyone believed this at the time.
- 32:39Kagan's like, well, you know, if you think about the catalyst itself, we don't actually know how it works.
- 32:47And during a chemical reaction, we've got this metal atom that's doing a lot of the work.
- 32:52But the metal atom could be doing different things if there are multiple agents involved.
- 33:01Metal atoms normally react...
- 33:03and interact with several molecules simultaneously.
- 33:06They're not just like, oh, I'm going to stick to this guy.
- 33:09They're recruiting all sorts of other stuff.
- 33:11And that's why metals like zinc and things like that are very important for our body as cofactors, because they actually help proteins recruit all sorts of other types of stuff.
- 33:21Now, here's what he considers, right?
- 33:25Suppose we've got two chiral molecules.
- 33:30that are catalysts.
- 33:30There's a left-handed version and a right-handed version, and we combine it with a metal atom, right?
- 33:36Now, this metal atom is going to recruit two of these
- 33:40to create mixtures.
- 33:42So we're going to get three possibilities.
- 33:43We're going to get a right-right mixture, a left-right mixture, and then a left-left mixture, right?
- 33:50But because of combinatorics, if I start out with a certain asymmetry, that asymmetry is only going to grow because of my mixtures.
- 33:58For example, if I start out with 25% and 75%, I'm going to end up with
- 34:056% and 56%.
- 34:08Like if I start out with 25% left, the combinatorics there is going to be 0.25 squared, which is going to be 0.625.
- 34:16So these guys are rounding to... Boo.
- 34:19They should say 6.25%, but this is the popular information and they don't want to deal with decimals like for the plebs, but it should really be 6.25%.
- 34:27That makes sense.
- 34:29If you guys are taking the GRE,
- 34:31Don't round.
- 34:32Don't do that.
- 34:34So you get 6.25% of the left-hand side.
- 34:37You get something like, I think it's 56.25%, or I don't know what the, you know what I mean, of the right-right.
- 34:44And then the mixture is going to be about 38%.
- 34:47It's really 37 point something something percent.
- 34:50But that's the key distinction now, right?
- 34:52So you've made these mixtures of molecules that have a different...
- 34:58than what you started it's not that same linear ratio we just talked about previously exactly and now if you create this type of multi-molecular interaction and you try to run your reaction through what are the products going to look like
- 35:18This is the big paper that comes out in 1986 in the Journal of Chemical Society, the Journal of the American Chemical Society.
- 35:26He shows that actually for a particular type of reaction called the Sharpless Epoxidation of Geronial, which is depicted on the lower there.
- 35:38we don't get a line.
- 35:39We get a nonlinear effect.
- 35:41If I increase the amount of asymmetry or I increase the amount of right-handed versus left-handed, I don't get a straight line.
- 35:49I actually get a difference.
- 35:51I get a slope that is very, very much a nonlinear effect.
- 35:55The type of reaction here is the Sharpless epoxidation that's named after Barry Sharpless, who won the Nobel Prize in 2001.
- 36:01So this is building on some of the asymmetric oxidation stuff that
- 36:06Barry Sharpless had done earlier on.
- 36:09The left-right catalyst behaves differently.
- 36:12And that is the key distinction that he's trying to make.
- 36:16So theoretically, what's happening, he actually tries and figures it out.
- 36:19Now we have the complete fixture, right?
- 36:21We've created these left-right catalysts, and we've created the left-left and the right-left.
- 36:27Sorry, left-left and the right-right, right?
- 36:29Right.
- 36:31What ends up happening is the left-right catalyst, the mixture, can't do anything.
- 36:37It is completely useless.
- 36:40Inert?
- 36:41Yeah, in some sense.
- 36:42It can't react with anything because I guess it's getting confused about which type of reactant to make.
- 36:50And now, at the very end, you're taking out that middle 38 portion.
- 36:54Yeah, yeah, from before.
- 36:55And you get a huge asymmetry.
- 36:57Yeah, yep, yep.
- 36:58Right?
- 36:59Before we had 6%, 38%, 56%.
- 37:02But the 38% is not creating any reactants.
- 37:06And so if we look at the reactant distribution...
- 37:09We only get 10% of reactants and 90% of the right version.
- 37:1710% of the left version and 90% of the right version.
- 37:20Which is basically taking up all of the product that would have come out of the left-right because effectively it cannot catalyze.
- 37:28Yeah, there's no catalysis happening.
- 37:30And so this is nonlinear.
- 37:31Yeah.
- 37:32Because you're starting...
- 37:33Yeah.
- 37:34With 25%, 75%.
- 37:37And you're ending up with a 10% and a 90%.
- 37:40And specifically, this mixing mechanism is a multiplicative thing, right?
- 37:48Which is why we're getting that slope, right?
- 37:50If it was just an additive thing, that the slope would just change.
- 37:55But like, it would still be a straight line.
- 37:57The fact that it's multiplicative means that I'm getting a parabola, right?
- 38:01Yep.
- 38:02And that's why you've got a curve in that reaction kinetics.
- 38:07Yep.
- 38:08That's the key distinction that's happening.
- 38:10This is the positive nonlinear effect.
- 38:13And this is the nonlinear part.
- 38:16Of the Nobel Prize discovery.
- 38:17Exactly.
- 38:18So if we go back to the top here, right, the official citation is for the discovery of nonlinear effects –
- 38:27and autocatalysis and asymmetric organic synthesis.
- 38:31So now we've identified, this is the first piece.
- 38:34Yeah, the nonlinear effects, right?
- 38:37And this is a historic breakthrough.
- 38:39It's historic because many chemists didn't think it was possible.
- 38:43And now they start exploring this new phenomenon.
- 38:46Everyone in chemistry who cares anything about asymmetric catalysis starts exploring this.
- 38:51One of these chemists is Kenzo Soai at the Tokyo University of Science.
- 38:57in that Nobel Prize citation.
- 39:00And before we get to that, let's do some housekeeping because we haven't done that in a while, and I think we deserve it.
- 39:06A quick opportunity to shill, a quick pause.
- 39:09So you can find all of the papers that we talk about and go through on the show at our website, ffppod.com.
- 39:17We do short clips and little bite-sized takes of some of the best science that we talk about on our socials.
- 39:24at FFP pod.
- 39:26And, you know, one of the best ways to help this show get seen by more people, the like, share a comment, share it with somebody you think would find it interesting.
- 39:35Five star on Spotify or any of the podcast networks really helps us get the best science show on the planet out to more people.
- 39:44And I just want to note, I was so excited when I saw the announcement this morning, because one of the, and you mentioned this earlier,
- 39:54One of the biggest unlock episodes for me in terms of my mental framework around the sciences was when we talked about, due to the unfortunate passing of Chen Ningyong at the end of last year, we have an episode, The Man Who Unlocked Symmetry.
- 40:11If any of these concepts are super interesting to you and you want to know more, whether it's about parody violation or the birth of Yang Mills, that episode is an absolute banger.
- 40:21Yeah, it really is.
- 40:22And the one thing that I want to mention about that episode and its distinction with this one is the fact that physics does care about the mirror world.
- 40:31Yes.
- 40:31Right?
- 40:32In chemistry, as we said, you can create a petri dish of both left-handed and right-handed stuff.
- 40:37And you might be thinking, well, you know, does everything in physics...
- 40:42care about left-handed, right-handed or not.
- 40:44Like in chemistry, clearly it doesn't.
- 40:46In physics, in fact, there is a way to tell between left-handed and right-handed stuff.
- 40:51And we do this great analysis that Richard Feynman actually originally did, where he talked about, you know, if we were to call up an alien...
- 41:00How would we tell him left versus right hands, right?
- 41:03We can't use chemistry.
- 41:04We can't be like, grow some glucose and then make it go through light and see which way the light turns.
- 41:11Because the glucose on Earth, sure, it's turning to the right-hand side because glucose is right-handed here on Earth.
- 41:17But the alien is going to grow crystals.
- 41:19And then like Louis Pasteur, he's going to be like, well, there's two different types of crystals.
- 41:23And like this type of crystal is going left-hand, this type of crystal is going right-hand.
- 41:28Or in the worst case scenario, the alien has a left-handed version of life, right?
- 41:33He's still somehow eating glucose, but his version of glucose is all left-handed.
- 41:38And so he goes the other way, and he thinks his left is our right.
- 41:43Chemistry cannot make that distinction.
- 41:46Physics, on the other hand, can.
- 41:47Chen Ningyang was one of the key people who understood that.
- 41:52And C.S.
- 41:53Wu, the very famous Chinese physicist, she did not win the Nobel Prize very controversially, but she proved that that was in fact...
- 42:02a fact of the universe that parody violation exists in beta decay where neutrons spit out, um, a proton and an electron, but the electron only spins in one direction versus the other.
- 42:13It's an incredible episode.
- 42:14It's actually one of my favorites as well.
- 42:15It's so good.
- 42:16And beta decay coming up again.
- 42:18Yeah.
- 42:18We talked about beta decay yesterday.
- 42:20So yeah.
- 42:21Um,
- 42:22Okay, so with that said, we now have the nonlinear part of this 2026 chemistry, Nobel.
- 42:28The next word in the Nobel description is autocatalysis.
- 42:32How do we get there?
- 42:33Yes, this is where we get into autocatalysis.
- 42:40The idea of autocatalysis is that the product participates in catalyzing the reaction that produces more of the product that then catalyzes more of the reaction that produces more of the product.
- 42:50So as the product accumulates, you get this runaway reaction.
- 42:53And a signature of this type of reaction in reaction kinetics is as time goes on, you get kind of a sigmoid where the first half –
- 43:02is like exponential because the more and more products you get, you start blowing up.
- 43:08But as you start running out of the reactants, you reach a baseline where all of the reactants are finally taken care of.
- 43:16Life has a bunch of this type of autocatalysis.
- 43:19For example, there's several cycles that we have in life where you create a particular product,
- 43:26And then that particular product feeds back into the cycle itself.
- 43:29The Krebs cycle in mitochondria is a great one.
- 43:33The Calvin cycle in photosynthesis is a great one.
- 43:36So life does this all the time, right?
- 43:38And you can imagine like...
- 43:40Kind of makes sense, right?
- 43:41If you've got a workshop that builds tools and then the tools build themselves, then you've got this thing going.
- 43:48This is not recursive self-improvement and we're not talking about AI.
- 43:52Yeah, we're not talking about AI, although that is also a runaway effect that we should be certainly concerned about.
- 43:59In any case, so Soai and his collaborators, they start exploring reactions in which organozinc reagents add to aldehydes to make alcohols.
- 44:10Let's take this particular reaction here.
- 44:12This is an asymmetric catalytic addition of dimethyl zinc, which is the ME2ZN.
- 44:19ME is the methyl, so dimethyl group.
- 44:22This is being attached to a chiral ligand on the left-hand side.
- 44:27The pH is a phenyl group.
- 44:29That's a C6H5, okay?
- 44:31When you scrutinize this thing, look at the product.
- 44:34The product also has a phenyl with OH.
- 44:37Mm-hmm.
- 44:38It's a bit different from the reactant, but it's also kind of similar to the thing that is catalyzing the reaction at the very top, because it's got a phenyl group, an OH group, and extra carbon.
- 44:49And the carbon, if you can somehow attach it to the N-benzene feridine, the NBN over there, then perhaps you could make more of this stuff.
- 44:59Okay, so this is kind of a, like, you know, maybe there's something here.
- 45:04This sparks an idea, right?
- 45:05Perhaps you can design a reaction where the catalyst forms itself.
- 45:09Now, at this time, early 1990s, there's several known examples of autocatalytic reactions, but none that are asymmetric.
- 45:18There's several reactions of this thing doing it, but we need something that prefers one hand over the other.
- 45:24And by experimenting with many different molecules, SOI succeeds in finding a chiral substance called 5-pyramidal alkanol,
- 45:33I almost said alcohol.
- 45:34And chemists with their... Dude, I remember organic chemistry.
- 45:39Like, if you put down alcohol and not alkanol, which, by the way, the H kind of looks like an N. Like, you get a zero.
- 45:48So, oh my God, I hate it, Orgo.
- 45:51But in any case, five-pyramidal alkanol
- 45:55is a chiral substance that Soai finds that can create itself.
- 46:00And in a publication in 1995 in Nature, he describes this revolutionary experiment, asymmetric autocatalysis and the amplification of enantiomeric excess of a chiral molecule.
- 46:12Banger title.
- 46:13For anyone who is in the field, like this is like, oh, you did it.
- 46:18And this is literally like the word for word, some of the stuff that the Nobel Committee is citing, right?
- 46:23Asymmetric autocatalysis.
- 46:25So great title, 1995.
- 46:29It's not the end of his work because this is kind of halfway there.
- 46:33It starts with a 2% excess of one enantiomer and ends up with an excess of 87%.
- 46:39That's pretty good.
- 46:40But the reaction is not what life does because in life you start with a little bit of excess and you've got to get to 100%.
- 46:47It's the Riemann hypothesis.
- 46:49We got to rule out all of the non-trivial zeros.
- 46:52Yeah, yeah, yeah.
- 46:52Even when you get to 100 percent.
- 46:53Yeah, yeah.
- 46:54A little different.
- 46:55A little different.
- 46:55A little different.
- 46:56But at least this is like some statistical type thing, right?
- 46:59We're getting close.
- 47:00We're getting close.
- 47:00We're getting close, right?
- 47:02So another eight years, SOA's lab just continues their search, and they finally find the ultimate autocatalytic process.
- 47:09In 2003…
- 47:11They publish in the American Chemical Society Journal.
- 47:16This journal, by the way, is just one of the goats for chemistry.
- 47:21In last year's episode, if you look back, a lot of the MOFs, the Metal Organic Framework Papers, came out in the American Chemical Society Journal.
- 47:31So it kind of goes under the radar compared to nature, science, but...
- 47:36We see you.
- 47:37Yeah, we see you.
- 47:37This thing is a heavy hitter.
- 47:40This is the first time that anyone had successfully created chirality from non-chiral combinations of molecules since the dawn of life.
- 47:47This is where he got to 100% chiral.
- 47:48Sheesh.
- 47:50Unbelievable.
- 47:51Since the dawn of life.
- 47:52Yeah, since the dawn of life, this is the first time.
- 47:56It's called the Soi reaction, and it is considered by chemists as the most elegant chemical experiment
- 48:05ever conducted by some chemists.
- 48:07I just want to note the pronunciation of the last name, So I, being the one that created this, is also just like a sort of aesthetically interesting naming convention.
- 48:19It's like, So I and I only.
- 48:21Yeah, I think that is quite funny.
- 48:24I mean, it's considered one of the most elegant chemical experiments ever conducted, which that is a high bar to me.
- 48:32So here's what's happening.
- 48:33When you start the catalytic process, you've got both enantiomers that are present, but a tiny excess of just one creates 100% excess of that one, and that's because...
- 48:47Effectively, what's happening is one enantiomer takes over the entire reaction.
- 48:52The left-hand side creates only left-hand catalysts, and the right-hand side creates only right-hand catalysts.
- 48:58But if you've got a tiny imbalance, the left-hand sides create way more than the right-hand side, which is going to then create way more, which is then going to create way more.
- 49:06So you start out with something like 0.00005%.
- 49:09After the first...
- 49:14run, you get all the way to 57%.
- 49:16Unbelievable.
- 49:18After the second run, you get to 99%.
- 49:20And after the third run, you get to 99.5%.
- 49:23It's a runaway reaction because of autocatalysis.
- 49:27That is the key.
- 49:28The thing is creating itself, which is then creating itself.
- 49:32Right?
- 49:35I remember seeing this image in the Nobel materials.
- 49:38And without necessarily connecting the dots...
- 49:43understanding, like looking at this runaway in three runs and three rounds, uh, with how small your starting point was in terms of the imbalance clearly was going to be important.
- 49:53Yeah.
- 49:54Now the connection as to how and why is fascinating.
- 49:57Yeah.
- 49:57And this is, it's like one part in what?
- 50:0010,000.
- 50:00I think if I'm doing the math, right.
- 50:02One part in 10,000 is leading to in three runs, 99.5%, almost at a hundred.
- 50:08Right.
- 50:09Just one of them is just dominating just because of the chance.
- 50:13Right.
- 50:14Beginning asymmetry.
- 50:15And the small scale of that chance asymmetry at the beginning is very small.
- 50:21Yeah.
- 50:21Yeah.
- 50:22It could have gone the other way.
- 50:23Right.
- 50:23And then in which case we would have had a lot of the of the left hand side.
- 50:28This is so good.
- 50:29And so now we've kind of gotten to the point where we understand now all of the component parts of the description.
- 50:38And just to say it one more time, the nonlinear effects.
- 50:42That was Kagan.
- 50:43That was Kagan.
- 50:44Kagan.
- 50:45Kogan, yeah.
- 50:46No, no.
- 50:47And then if it's not, you can let us know in the comments.
- 50:49Yeah, please.
- 50:51And then autocatalysis, which is what creates this runaway, in asymmetric organic synthesis, which means the inputs –
- 51:01uh have that slight asymmetry and it only it doesn't always have to have a slight asymmetry but it only requires a slight asymmetry in this example to then create this 100 runaway reaction um and this is fascinating for a lot of reasons obviously we made the connection earlier to uh how you know a couple of things but one of the notes was that
- 51:23this changes how we make medicines or pharmaceuticals.
- 51:28So how does that connect to the impacts now that we have this understanding?
- 51:32Yeah, and this leads to some of why chemists are so motivated by this.
- 51:38The aim is to produce enantiomers that are as pure as possible.
- 51:42For example, in pharmaceutical manufacturing, you want a particular type of handedness
- 51:47for the drug that you're making.
- 51:48You don't want to do Louis Pasteur where you've got both sides.
- 51:52The importance of achieving this has been shown by the thalidomide, the thalidomide scandal of the 1960s.
- 52:00I don't know if you're aware of this.
- 52:02I was not.
- 52:03But this is an incredibly dark time in chemistry, in pharmaceuticals, and in the world at large.
- 52:11Like, aside from war, this is one of the worst disasters
- 52:16In history that I hadn't really heard about, which I was really surprised by.
- 52:20So this is the thalidomide scandal of the 1960s when thousands of children were affected by birth defects caused by a sedative, thalidomide.
- 52:29It was widely given to pregnant women to treat morning sickness.
- 52:34It's actually incredible that there's so little testing on pregnant women to create such a tragedy.
- 52:40Tens of thousands of people were affected.
- 52:44And when researchers analyzed what had happened, they'd realized that it was an active substance.
- 52:50The mirror image was causing the harm, right?
- 52:54Both mirror images were in the drug.
- 52:57And while one of the...
- 52:59one of the mirror images was actually creating the sedative version.
- 53:02The other mirror image was causing these defects.
- 53:05And I want to take a brief note here and talk about why the world at large was very much affected by the thalidomide scandal.
- 53:14Tens of thousands, I'm talking literally, tens of thousands of birth defects.
- 53:18The U.S. was spared because of Francis Oldham Kelsey.
- 53:23And if you go back to that photo that we had, mm-hmm.
- 53:29Frances Oldham Kelsey is the hero in our story for America because she was a pharmacologist working for the U.S. Food and Drug Administration.
- 53:37She blocked the drug's approval in the United States despite heavy pressure from the manufacturer Grunenthal, which was a German pharmaceutical company.
- 53:48They were trying to pressure the FDA to approve this thing.
- 53:52She saw the writing on the wall in early clinical studies that others had kind of just hand-waved as like, oh, that's just a hand of God, like, chance stuff.
- 54:02She was looking at the data going, no, no, there's clearly an effect here.
- 54:05I don't know what you guys are talking about.
- 54:07She received a lot of pressure.
- 54:10from lobbyists, from like, you know, I can imagine like as a woman at the time in the 1960s in the Food and Drug Administration as a scientist trying to block approval.
- 54:20But, you know, it took her and it largely spared the US from this crisis.
- 54:25There are several other countries that are still dealing with this.
- 54:28Japan, Australia, a lot of Europe.
- 54:32These are developed nations that have their own versions of the Food and Drug Administration.
- 54:37But somehow the pressure from Grunenthal
- 54:39like actually, you know, they succumb to that pressure.
- 54:42We did not because of her.
- 54:45And, you know, there's a photo of President John F. Kennedy giving her the President's Award for Distinguished Federal Civilian Service.
- 54:53It highlights why the FDA is important.
- 54:57I want to bring this up in today's climate where...
- 55:01Apparently, we're just making decisions with the FDA that don't make sense to me, don't make sense to a lot of trained scientists.
- 55:11I just wanted to show that this is one of those situations where you really need independent thinkers in our government to make informed decisions.
- 55:20America was spared from that crisis.
- 55:23When the next crisis comes, we need someone like Francis Oldham Kelsey to do that again.
- 55:30And just to piggyback on that, I think this also highlights the importance of not allowing commercial influence in America.
- 55:41sort of public health decisions 100 as well as research and r&d decisions there needs to be a healthy tension there um and this is a perfect example of you don't want it to become too late because you've allowed sort of this runaway corporatism to infect
- 56:04civic institutions to their own benefit for the sake of shareholder value at the expense of a potential catastrophe that can last generations.
- 56:15And that's, these decisions can last generations.
- 56:18Right.
- 56:18And these countries are still dealing with it to this day.
- 56:20I think it was only the last decade when that German company... Yeah, very good.
- 56:27Yeah.
- 56:27But only in the last decade was that
- 56:32Which is like 50 years later.
- 56:34Yeah.
- 56:34Really?
- 56:35And a lot of...
- 56:36I mean, I went in a deep dive on this.
- 56:38A lot of the original scientists and shareholders and the CEO of that company in the 1960s that was peddling this thing, they were just trying to avoid any sort of responsibility.
- 56:49They avoided responsibility for most of their life until most of them had passed away.
- 56:53And then they had the repercussions.
- 56:57If you guys want to go into a deep dive about...
- 57:00like how badly things can go wrong, you should look up the thalidomide scandal of the early 1960s.
- 57:08But I think this highlights something about drug development, which is chirality is a practical design and quality control issue, right?
- 57:14If two mirror images interact differently with the body, then the manufacturer needs to understand which form is being made, how much of it is being made, and how we can actually create asymmetric synthesis where we can build a preference of one over another, right?
- 57:28Understanding these nonlinear effects...
- 57:32helps researchers interpret experiments, identify active species, and decide how to actually improve selectivity.
- 57:38So this year's Nobel Prizes, the work that they've done is very much important for drug development at large.
- 57:48this is it's so interesting i think you know i've talked about this previously you know my dad has worked in stage one drug discovery for quite some time um and this is one of those things where you know even in the course of his career uh the change of understanding has impacted what he's been able to do and work on and that it's always touching on stories that have a tangential connection to allow me to understand his work a little bit better i always find uh
- 58:15Gratifying.
- 58:16And I know you feel the same when we talk about stuff in the other category for you as well.
- 58:21But I think this now brings us back to the last missing piece from the beginning of the episode setup, which comes back to this age old question about...
- 58:31life.
- 58:32So how does this now, you know, what does all of this say about why biology is homochiral?
- 58:40It only has one chirality.
- 58:43Like, how does this now connect to that bigger question?
- 58:46Right, right.
- 58:47And you might think that this sort of answers it, right?
- 58:49Because the So I reaction shows that you can start with a small asymmetry and get, you know, 100% one way or the other.
- 58:56Now, that is certainly true.
- 58:58And it has a lot of
- 59:00compounding effects for drug development, as we talked about, and fundamental chemistry questions at large.
- 59:05But at the end of the day, the SOI reaction is artificial, and it is a bit different from the chemistry of life.
- 59:11It still awakens a new enthusiasm in chemists who want to understand life's origins, but the connection to life is limited in some sense, because these experiments demonstrate that the chemical route from little or no-handedness
- 59:27to a very strong preference for handedness that is certainly possible.
- 59:31Whether the mechanism 4 billion years ago was exactly the Sawai reaction or some other part, it's not entirely possible.
- 59:40clear right i mean there's the extreme case where life came from outer space and that already had a handedness so then you know that answers the question so so pan-spermia yeah so origin of life is a is a very is a very different question but this certainly gets to things that are possible right you know it tells you that you don't need like an outside
- 1:00:05Like, agent.
- 1:00:06Invisible hand.
- 1:00:06Yeah, invisible hand, vitalism, like some mysterious force that's in life that creates these building blocks one way or the other.
- 1:00:14Now, around the world, researchers are taking the next step, and they're trying to repeat Psoa's achievement, but with the aim of producing homochiral amino acids and sugars.
- 1:00:24Right now, we've done simple molecules.
- 1:00:26We'd like to make even more complicated molecules, but we need to be careful.
- 1:00:29Okay.
- 1:00:30Okay?
- 1:00:30We do not want to make mirror life.
- 1:00:33Okay.
- 1:00:34And in the recent times, we've had a lot of, like, alarmist news coming out about Mirror Life.
- 1:00:42We have more doomers?
- 1:00:43We have a lot of doomers.
- 1:00:45There's AI doomers.
- 1:00:46The Mirror Life doomers have been around for a while.
- 1:00:49Okay?
- 1:00:49Ever since we figured out that life is chiral.
- 1:00:52And we've been able to make asymmetric catalysis happen.
- 1:00:56There have been mirror life doomers that are telling us not to do it.
- 1:01:01This is just a few of the headlines.
- 1:01:03Mirror life is still hypothetical.
- 1:01:05Here's why it should probably stay that way.
- 1:01:07There was a news article in Nature that said, how should mirror life research be restricted?
- 1:01:12The debate heats up.
- 1:01:13My favorite one is mirror life is a mass extinction risk we don't need to take.
- 1:01:20I want to go a little bit into some of this.
- 1:01:23So what is mirror life?
- 1:01:24What it means is the molecules and the proteins that make up these organisms would be completely mirrored from the ones that we have.
- 1:01:33This would require mirrored sugars, mirrored DNA, mirrored proteins, like everything, literally everything that this particular life form that we create would have the opposite version.
- 1:01:50has issues if it is created and if it escapes the lab.
- 1:01:55Some really, really bad issues, okay?
- 1:01:57Because suppose you create a mirror bacterium, like a bacteria where everything is the opposite chirality from normal life, okay?
- 1:02:09So that means the amino acids are right-handed.
- 1:02:11That means the sugars are left-handed.
- 1:02:13Everything is opposite.
- 1:02:15What that means is that you can have a bacteria that...
- 1:02:20proliferates, but there is no defense mechanism on the earth that is suited to combat this thing.
- 1:02:29The viruses, like the bacteriophages that prey on the bacteria, they require chiral mechanisms to get into the bacteria.
- 1:02:37Well, if the bacteria has the opposite-handedness, the virus can't really screw itself into the bacterium and kill it.
- 1:02:44It can't.
- 1:02:45The Lego blocks don't.
- 1:02:46Yeah.
- 1:02:46A lot of our antibiotics...
- 1:02:48are chiral in nature, and they require the specific chirality of the bacterial proteins to attach and then destroy.
- 1:02:57Now you've got, you know, there's no predation, there's no effective predation, and the accompanying increase in the bacteria would create this runaway reaction, because the bacteria would just start eating, suppose it's photosynthetic, right?
- 1:03:10It doesn't, it would just, like all it needs is water, which is not chiral, carbon dioxide, which is not chiral, and sunlight.
- 1:03:18Which is not chiral.
- 1:03:20And it would just create the opposite type of glucose, the opposite type of proteins.
- 1:03:24Boom.
- 1:03:24You get a runaway reaction, right?
- 1:03:26Mm-hmm.
- 1:03:28In humans, we've got an innate human immune system, and the first line of human defense in the immune system against microbial threats relies on a pattern of recognition where you've got antibodies reacting to the invaders, or you've got antigens.
- 1:03:43No, the antigens are the invaders.
- 1:03:45The antibodies react to them, recognize, and then you've got the second line of defense that characterizes, okay, we need to start an immune response.
- 1:03:53Well, if our antibodies do not...
- 1:03:56recognize the antigens and they have no hope of recognizing the antigens because they can't because you literally can't make the opposite chirality antibody yeah that that's dangerous right that's dangerous yeah it's this is getting weird right um so immune systems will go bad instead of causing standard infections the mirror pathogen is going to act more like a cancer
- 1:04:23because we're not gonna even have an immune response to this thing.
- 1:04:26The mirror pathogen is just gonna go in and it's gonna start occupying space.
- 1:04:30It's gonna start reproducing and creating a runaway reproductive reaction that's gonna use bodily energy resources and there's gonna be no existing countermeasures.
- 1:04:42This is a very scary prospect, right?
- 1:04:46So image mirror life is really quite a danger.
- 1:04:51OG Doomers might be on to something there.
- 1:04:53Yeah, yeah.
- 1:04:54This is from way back, and they've been calling for bans on this thing for a very long time.
- 1:04:59Now, what's the current status?
- 1:05:01Now, mirror life does not exist, and it can't form naturally because natural...
- 1:05:06So biology prefers one-handedness and mirror life is necessarily the other-handedness.
- 1:05:11Should we put a qualifier there that says on Earth?
- 1:05:14On Earth.
- 1:05:15We should.
- 1:05:16Just as a – not that it's – Yeah.
- 1:05:18We haven't seen extraterrestrial life at this point in time.
- 1:05:21Yeah.
- 1:05:21But –
- 1:05:22That's also a reason why bringing stuff back is not a good idea as well.
- 1:05:26Yes, exactly.
- 1:05:28And that's also a reason why bringing stuff there is not a good idea as well, right?
- 1:05:32So that's why when we go to places like Europa to look for life, we better know that all of our equipment is sterilized in some sense, right?
- 1:05:40Because Europa could have the other handedness of life.
- 1:05:44Now, it's challenging to build mirrored life, right?
- 1:05:47You need to create a central dogma that is a mirrored central dogma.
- 1:05:50Like, for example, nobody's created a mirrored ribosome where all of the amino acids and all of the RNA are exactly the opposite type, let alone some major components like the tRNAs that are required for protein synthesis and things like that.
- 1:06:05You would need a mirrored DNA.
- 1:06:07You would need a mirrored RNA.
- 1:06:09You would need mirrored RNA polymerases.
- 1:06:11So all of this stuff needs to happen.
- 1:06:13And like you'd really need to like try.
- 1:06:16Yeah, yeah, yeah.
- 1:06:17You know?
- 1:06:17Yeah.
- 1:06:18Um, it, it, there's so many similarities with the ongoing AI safety conversation, just in terms of like, there being two camps, people are like, this shouldn't happen.
- 1:06:27Uh, and then other folks saying, well, we don't even, we're not even close.
- 1:06:31Yeah.
- 1:06:31Right.
- 1:06:32It has that same, uh, dynamic.
- 1:06:34Um, um,
- 1:06:36Part of the challenge with things like this is because we are increasing in our ability to do scientific innovation generally, AI enabled or not, the gap time between we don't have any of the component parts to having the component parts.
- 1:06:50It's not necessarily the time compression there is non-trivial.
- 1:06:53Exactly.
- 1:06:54Yeah.
- 1:06:54And so right now, the best we've got is like a scientific moratorium.
- 1:06:59OK, in 2024, there was an international coalition of 38 leading scientists, including some Nobel laureates.
- 1:07:05They published this landmark call for a halt.
- 1:07:09And what they're effectively doing is like a taboo strategy.
- 1:07:12Like, I'm not going to review papers that...
- 1:07:16you know, forward mirror life.
- 1:07:18Maybe we don't fund research that forwards mirror life.
- 1:07:21There's major international bodies that recently issued critical reports like the UNESCO international bioethics committee, the world health organization, the UN secretary general's scientific advisory, but like,
- 1:07:33Yeah, we've seen how in the current world environment, geopolitically and otherwise, unfortunately, these entities that are meant to create collective action have struggled.
- 1:07:44Yeah.
- 1:07:46And we've seen a breakdown, unfortunately, in the ability to get global collaboration on things.
- 1:07:53a lot of different things.
- 1:07:54Yeah.
- 1:07:54So we're kind of in a tough spot.
- 1:07:55Yeah.
- 1:07:56And it's complicated by the fact that not everyone even agrees that we should just like sweepingly ban this thing.
- 1:08:01There's some synthetic biologists that argue that a blanket ban would be premature because we're so far away from it.
- 1:08:07And, you know, mirror image peptides and biomolecules, they can currently be used to design safer, highly stable drugs.
- 1:08:14You know, beneficial mirror molecules can make...
- 1:08:19better drugs effectively and that's very far away from living self-replicating mirror cells sounds a lot like sam altman right yeah um i don't think there's a whole like usa versus china debate here right because i think everyone agrees that let's not do this um but there's no like supremacy mirror life supremacy going on but but there's there's some like debate about you know maybe not a blanket ban it kind of reminds me of you know um when we were talking about
- 1:08:49Sudhir Parikh, the CEO of AAAS, he was talking about how some of the advice that he gave the Senate Scientific Advisory Committee was used on the floor of Congress to, like, steer legislation.
- 1:09:05One of the examples that he gave us, and we'll have the interview coming out soon, he said that, you know, there was a ban for any chimeras of human, animal, or animal, animal animals.
- 1:09:18Well, the blanket ban would stop any genetic modification from happening, right?
- 1:09:25And that's a huge ban, right?
- 1:09:27So there's, like, room to do this, but at the same time, like...
- 1:09:34like animal animal chimeras are not an existential risk for all life on earth so the fact that like right now we're just we're just oh it's taboo like let's not do it guys i think we should have a little i think we should get our act together here guys like the more i researched this i was like how are we just how are we just like let's not do it guys that's like our best strategy
- 1:10:00It doesn't make any sense.
- 1:10:01And it's fascinating because once you get into the details to understand what's functionally happening –
- 1:10:07It's clear where the risk comes from.
- 1:10:09Exactly.
- 1:10:10It's a lot easier to see the risk than some of the RSI debate.
- 1:10:14Although I am more doomer than non-doomer on recursive self-improvement.
- 1:10:18But I think it requires more infrastructure around it.
- 1:10:23This is like once it's created and it's out.
- 1:10:25No, it's like – It's really bad.
- 1:10:27It's really bad.
- 1:10:27It's really bad.
- 1:10:28All you need is like one bacteria.
- 1:10:30Right.
- 1:10:30Exactly.
- 1:10:31Yeah.
- 1:10:31Exactly.
- 1:10:32So –
- 1:10:33I'm going to end on a lighter note than existential dread.
- 1:10:37Before we end, I want to mention that I'm pretty sure I caught a mistake by the Nobel Committee's press material.
- 1:10:44Uh-oh.
- 1:10:45Okay?
- 1:10:45So on the left-hand side is the popular science background.
- 1:10:50That's an image of the Sawa chemical reaction.
- 1:10:55The intermediary is the left and right versions of the catalyst that then, you know, auto catalyze themselves and create the runaway reaction.
- 1:11:04And...
- 1:11:05If you notice on the left-hand side, the colored versions, this is the popular science.
- 1:11:09So, you know, they got some graphic artists to, like, make this version.
- 1:11:14They're showing the left version of it and then the right version of it.
- 1:11:18It's flipped.
- 1:11:18Yes.
- 1:11:19Right?
- 1:11:19Okay.
- 1:11:20But let's look at the molecule in a little bit greater detail, okay?
- 1:11:27If this molecule was completely flat...
- 1:11:30then all I'd have to do is just flip the left into the right.
- 1:11:33And then I would, those two are not enantiomers if they're completely flat.
- 1:11:38The fact that they're not flat comes from the fact that on the left, there's a dotted line that's attaching the zinc group to the organic molecule.
- 1:11:48And on the right-hand side, there's a solid line that is attaching the zinc to the solid molecule.
- 1:11:53Now in chemistry, the convention is dotted line means it's moving away.
- 1:11:58And solid line means it's moving towards.
- 1:12:01But if you're flipping it, then the zinc that's away on the left-hand side, as I turn it and flip it, the zinc is going to come towards me on the right-hand side.
- 1:12:16Those two are the same molecule, right?
- 1:12:19In the scientific background, they were a bit more careful because I think they just copy and pasted the image from the paper itself.
- 1:12:27And there, it's showing the left and the right versions of that molecule.
- 1:12:34It's not flipped.
- 1:12:35Right.
- 1:12:36And one of them is dotted going away.
- 1:12:38One of them is solid going towards.
- 1:12:40Uh-oh.
- 1:12:42Right?
- 1:12:42I see it.
- 1:12:43Yeah, so on the left-hand side, what would have been correct is both of them are either dotted or you don't flip.
- 1:12:50And one of them is dotted.
- 1:12:51One of them is solid.
- 1:12:52Yep, yep.
- 1:12:52You see what I'm saying?
- 1:12:53I see exactly what you're saying.
- 1:12:54Because by having it flipped in this orientation, you're actually changing the in and outness of the zinc.
- 1:12:59Yeah, yeah.
- 1:13:00Yeah, the zinc is going away from me on the left, but if I flip it to the right, it would be coming towards me.
- 1:13:05It's the same molecule.
- 1:13:07On the other hand, if it's the opposite version, then...
- 1:13:10As I flip it, it would be a dotted line on the right as well.
- 1:13:14We're awaiting comments.
- 1:13:16Right.
- 1:13:16So if there's any chemists out there that like have some justification for this, like let me know.
- 1:13:21But I'm pretty sure the Nobel Committee made a mistake here.
- 1:13:24The Nobel Committee has been very quiet since this tweet.
- 1:13:27You know?
- 1:13:28But given what we've gone through, it makes total sense why these are representing different things.
- 1:13:34Yeah, yeah.
- 1:13:35On the right-hand side, we're seeing true chirality, right?
- 1:13:37We're seeing the enantiomers that are left-handed and right-handed.
- 1:13:42On the left-hand side, we're actually seeing the same molecule.
- 1:13:44Yeah, yeah.
- 1:13:45Because all you're doing is rotating it.
- 1:13:48Oh, that's a good one.
- 1:13:50In case people didn't think we did our homework.
- 1:13:53Yeah.
- 1:13:54This is proof positive that we spend the time.
- 1:13:59So in the comments, right?
- 1:14:00FFP pod greater than Nobel Committee.
- 1:14:03Let's go.
- 1:14:05Or I'm wrong and let me know.
- 1:14:10We have spent a lot of time this week waking up early, putting all these materials together so we could have had daily drops with the detailed understandings of each of the moving parts.
- 1:14:20I just want to quickly kind of go through what we've talked about today.
- 1:14:23So we started with two hands that cannot be made identical by rotating them.
- 1:14:29From that small geometric difference, we reached a problem that connects the molecules in medicine to,
- 1:14:34to the building blocks of life.
- 1:14:36Pasteur, Louis Pasteur, made molecular symmetry experimentally visible.
- 1:14:42This was our wine example earlier.
- 1:14:44Cagan showed why the behavior of mixed-handed catalyst need not be a simple average.
- 1:14:50And so I demonstrated a reaction in which self-production and amplification work together.
- 1:14:56This non-linearity we talked about then, this autocatalysis theory.
- 1:15:00A tiny starting imbalance does not always stay tiny.
- 1:15:03Fascinating.
- 1:15:03Under the right chemical conditions, it can shape almost the entire outcome.
- 1:15:08That is the idea behind this year's Chemistry Nobel.
- 1:15:12And it leaves an excellent question open.
- 1:15:15Which other chemical systems can turn a small beginning into a strongly ordered result?
- 1:15:20Which is what we just ended on.
- 1:15:22Maybe we need to be a little bit careful about it.
- 1:15:24when it comes to some of the mirror life stuff.
- 1:15:26If there's a step in the story that you would like us to unpack further, in addition to the FFP Greater Than Nobel Committee in the comments, please let us know.
- 1:15:36Again, all the papers and the sources are available at ffppod.com.
- 1:15:41On socials, you can get all of our clips.
- 1:15:44at ffp pod uh oh look our little give it a like just popped up on the screen uh for those watching on youtube that timing was quite nice look that was no hands look mom no hands i i want to take a but i know this is running a little long but i want to just take a last moment since this is going to be our last episode from the nobels um i want to give a huge big uh shout out to our resident phd krishna chowdhury this week who's been an absolute champion of
- 1:16:10These are extremely dense and complex issues.
- 1:16:14As I mentioned, we are up all morning recording first thing after several hours to deliver a deeply technical but conversational and approachable podcast.
- 1:16:26episode right when it happens so you can really get this immediately.
- 1:16:31Krishna is a big part, not only in every episode, but especially in Nobel Prize week, for us to be able to deliver the correct and accurate and still
- 1:16:44enjoyable result here.
- 1:16:45And, you know, I really just want to give you some flowers.
- 1:16:49It's a hugely challenging thing for us to accomplish this, um, in, in, in this time period with just the two of us.
- 1:16:57Um, and to get it out to you with high production value, making us look pretty.
- 1:17:02Um, so, you know, in the comments, uh, if you made it to the end of the episode, please give Christian a big shout out because, um, this is, this is real work.
- 1:17:11And, uh,
- 1:17:12It's a pleasure to be able to produce this show alongside one of my favorite science communicators.
- 1:17:18My name is Lester Nare, alongside, again, one of my favorite people, Krishna.
- 1:17:25Is there anything from the week that you want to just end on before we let the people go here?
- 1:17:31I want to end on the fact that, you know, I think Nobel, I think in a grand scheme, if we zoom out,
- 1:17:39The Nobel Prizes are a great way to recognize scientists for a lifelong career in advancing a particular field.
- 1:17:49But prizes aren't everything.
- 1:17:52And science is so much bigger than the few individuals that get the Nobel Prize.
- 1:17:56Yeah.
- 1:17:57Even in today's episode, we talked about all of the stuff that led up to it.
- 1:18:01In the Ice Cube episode, I mean, there's 450 people involved in Ice Cube.
- 1:18:07Only one person got the Nobel Prize.
- 1:18:09It was his baby, and it kind of makes sense.
- 1:18:11But let's not forget about all of the scientists that work...
- 1:18:15for creating science.
- 1:18:18You know, they're just as much heroes as the Nobel Prize winners.
- 1:18:23And that's why a big part of the show is just highlighting science as it happens throughout the year.
- 1:18:28It's a team sport.
- 1:18:29This is not tennis.
- 1:18:31And again, we do always try to, for example, when we show the papers, show the whole author byline.
- 1:18:38So everyone gets that recognition.
- 1:18:39Yeah.
- 1:18:39Because I think it's a really good point.
- 1:18:41We are trying to create an entry point into this to make it enjoyable.
- 1:18:46But we are extremely grateful to the entire research community.
- 1:18:52And we are trying to elevate your stories in this love letter to science.
- 1:18:57And one thing I will also say is that, you know, the...
- 1:19:01Getting up at 2.30 in the morning, it's not just me.
- 1:19:04You're doing it too.
- 1:19:05And, you know, the fact that we can, like, produce this thing, release it day of, release a bunch of social clips the day of, that's all Lester.
- 1:19:15And, you know, be sure to look at, like, all of the advancements that we've had in our automatic caption creation and things like that.
- 1:19:23Pretty cool stuff.
- 1:19:25We are one of the best teams in science entertainment, and we are trying to build off the shoulders of giants of the many researchers who don't get their stories told as often as other things.
- 1:19:38And so it's a pleasure for us both to...
- 1:19:40To be able to bring the show to you for many of the new listeners, we have a great back catalog.
- 1:19:44Check it out.
- 1:19:45We are going to go get some rest.
- 1:19:50Next episode will be our interview episode from the Golden Goose Awards, which was, I can't believe that was last week.
- 1:19:57When we were in D.C., we'll have three interviews with all of the awardees that won this year and that will be followed up by our interview with AAAS CEO Sudip Parikh.
- 1:20:09And we may do a Halloween special, but we haven't decided.
- 1:20:13We're going to take a couple days for a breather.
- 1:20:15We appreciate you all and FFP Nation for joining us, and we will see you all next week.