[00:00:00] Speaker A: And you can see the amino acids build up, they plateau and then they start going away.
And so right away, you know, not only are they being produced, but they're being consumed.
And as the, as the gases get consumed and the amino acid production slows down, the consuming reactions take over.
[00:00:26] Speaker B: ID the Future, a podcast about evolution and intelligent design.
Hello and welcome to ID the Future. I'm Casey Luskin and today we have on the show with us a very special guest, and frankly, this is a podcast that I've been looking forward to doing for years. We have on the show with us today, Dr. Ed Peltzer. Ed holds an undergraduate degree in chemistry from Bucknell University and then he earned a PhD in Oceanography from Scripps Institution for Oceanography at the University of California, San Diego, studying some of the chemistry that produces organic molecules in meteorites. He studied there under Professor Jeffrey Bethe and also had the famous origin of life theorist Stanley Miller on his thesis committee. But Bethe is also a very well known origin of life theorist. And actually Bethe was one of my professors when I was taking courses at Scripps as a student at UC San Diego many years later.
And of course, Jeffrey Bethe is also a leader in the field of origin of life chemistry.
And so Ed himself is also an expert in prebiotic synthesis and origin of life chemistry, and his research was directly relevant to important questions related to the origin of life.
After earning his PhD, Ed went on to do research at the Woods Hole Oceanographic institute for about 20 years and eventually went to the Monterey Bay Research Aquarium Institute where he was a scientist for 27 years. And he recently retired. And he studied many interesting topics over the years, including the transport of dust particles in the atmosphere, dissolved organic carbon and seawater, and how to use remotely operated vehicles to study gas hydrates on the seafloor. So Ed has quite a prestigious and accomplished scientific career and most interestingly is that he has been a friend of intelligent design for many years. And in fact, some folks may have read over the years articles where I would cite and an anonymous chemist who was helping to advise me on origin of life chemistry questions, and that person was often Ed Peltzer because of his expertise in this issue. He's been a real resource to us at Discovery Institute over the years. So Ed, it's delightful to have you on ID the Future with us today.
[00:02:35] Speaker A: Thank you very much, Casey. That's quite an introduction.
[00:02:38] Speaker B: Well, Ed, you've been making the rounds recently. You did an interview with William Dembsky, you did an interview with Professor James tour on his YouTube channel. And you're kind of, you know, coming out of the closet, so to speak, after many years as a researcher, although you've been a friend of ID for many years, you kind of have been undercover because you did not want to, you know, harm your career, so to speak.
[00:03:00] Speaker A: Well, and in part it was worry about my career, but it was also where I was working.
You know, they. They don't have a, you know, a. A pony in the race, so to speak. But if somebody there is involved in something controversial, they get dragged into it.
And I didn't want to get them involved in things they didn't have any interest in.
[00:03:28] Speaker B: That's fair, I understand that. But unfortunately, it's just a sign of the world that we live in that unfortunately, there's nothing as much academic freedom as we would like for intelligent design. But let's take the story back a little bit.
What first got you personally interested in the question of origins?
You obviously studied the origin of life in your PhD thesis. What got you interested in these kinds of questions?
[00:03:52] Speaker A: Well, anybody that works in the life sciences will eventually wonder about how it all began.
And with that sort of as a background, I sort of backed into the field. I was taking a class in organic geochemistry from Jeff Beta in the spring of my first year as a graduate student, and he was talking about the Miller Urey experiment. And that was very shortly after the Murchison meteorite had fallen. And NASA had just released results of their analysis where they found a pattern of amino acids in the meteorite that was very similar to what people find in the Miller Urey experiment.
And they also were able to identify that these amino acids were racemic. So they were not of terrestrial origin. They were native to the meteorite.
And as Jeff explained it, there's the pathway that produces these amino acids is the Strecker cyanohydrin pathway. But that pathway has a fork, and the switching of the fork depends upon the ammonia concentration during the time of synthesis.
If ammonia is high, you get all amino acids. If there's no ammonia present, that pathway leads to only hydroxy acids.
And if it's somewhere in between, you get both.
So his offer to the class was if somebody wanted to look at this process, he had access to a sample from the Murchison meteorite, and it would make a great thesis topic.
And since it was close to the end of my first year, I was thinking about what I was going to do, and this seemed like too good of an opportunity to pass up.
So I Thought about it overnight and went to talk to Jeff the next day. And we went from there.
[00:06:01] Speaker B: That's fascinating, Ed.
So you then did your PhD thesis looking at basically how organic molecules are created in meteorites. And this is of great interest, of course, to origin of life theorists who want to say that maybe the molecules necessary for life, some of the building blocks of life, came to Earth from outer space.
So what did you find in your PhD?
I mean, obviously we know that there are pathways to create amino acids outside of biological organisms. I think that was known for a long time. But what did you find in your PhD thesis and what were sort of the implications for the origin of life?
[00:06:40] Speaker A: Well, what we found was a parallel series of hydroxy acids that were homologs of the amino acids. So same carbon length, same chain branching.
Instead of an amino group, they had a hydroxy group.
Fortunately for me, some of Stanley Miller's most recent students had worked out all the thermodynamics and kinetics of the Strecker cyanohydrin pathway.
So we were able to take the results of the hydroxy acids that we found, those concentrations and use them in a ratio with the amino acids to back calculate the ammonia concentration in the merchant meteorite parent body.
[00:07:30] Speaker B: So basically inferring what that primordial environment or gaseous mixture was to produce this. So give us a sense of this, Ed. How exactly do you produce amino acids in space? We think of space as being an empty environment.
There's not a lot. I mean, obviously there is matter in space, but is it too sparse to be able to do this kind of chemistry? How are they being produced in these meteorites?
[00:07:57] Speaker A: Well, the thought was, is that the meteorite was a fraction of a parent body, and then on the parent body there was enough mass that you had liquid water.
And the reaction takes place best in liquid water.
And that water would then be in equilibrium with the atmosphere of the parent body, and that's where the ammonia would be coming from.
It's in equilibrium with the atmosphere as well.
[00:08:32] Speaker B: Okay, so this little meteorite is actually a chunk of something much bigger that probably had a gravitational mass large enough to maintain some kind of an ammonia based atmosphere. Is that, that's kind of the idea?
[00:08:44] Speaker A: I guess that's exactly what, what we were thinking.
[00:08:48] Speaker B: Okay, so, I mean, I don't know how much you've followed this over the years. Do we see meteorites or asteroids or comets large enough in space to actually have an ammonia based atmosphere? Is this something that we actually observe? Or.
I mean, how well is this solidified.
[00:09:06] Speaker A: Well, I'm not aware that they've seen any small planets and this one would have to be one in our solar system.
Sure.
I'm not aware they've seen any of the small.
Actually these would be. The large asteroids would have an atmosphere.
I'm not aware that's been seen. We have seen several other carbonaceous chondrites fall and they had similar patterns of amino acids.
[00:09:46] Speaker B: Yeah, yeah, go ahead, go ahead.
[00:09:49] Speaker A: Sorry. Well, I was going to say, but nobody's looked at hydroxy acids in them as well.
It's a much trickier technique because the hydroxy acids are much more volatile and if you're not careful, they go away.
[00:10:07] Speaker B: Let's talk about these amino acids and meteorites a little bit more for just a moment because I know that obviously origin of life theorists get very excited when they see some non biological pathway to produce organic molecules. So that's what got the Miller Urey experiment so much attention. Of course, Stanley Miller was sort of the academic father of Jeffrey Bethe, and Jeffrey Bethe was the academic father of you in this sense. So you have a very prestigious academic lineage here.
But do these experiments, when they're producing amino acids, are they really showing a pathway towards life? I mean, I guess the question, to put a different way, the products of these reactions, the products of these experiments, are they really showing the kinds of molecules that we see in life or how close are they getting us to explaining how life originated?
[00:11:04] Speaker A: Well, there's two big problems that were seen in the Miller Urey experiment.
The first one was those amino acids that are produced are racemic.
[00:11:16] Speaker B: And what does that mean? Can you explain that for our listeners who may not know?
[00:11:20] Speaker A: Easiest way to think of it is that the molecules are left handed or right handed.
They have two isomeric forms that are mirror images of each other. Like your right hand is a mirror image of your left hand.
In biological systems, only the L amino acid is used.
So the D, the other form of the amino acid, isn't useful to the origin of life on Earth.
The other problem that is very often ignored is that the amino acids produced in the Miller Urey experiment are very low concentration.
And what is produced mostly in that experiment are dark red to black organic molecules that coat the inside of the synthesis apparatus.
And those are produced by, by the amino acids reacting with sugars that are produced simultaneously in a pathway called the Maillard reaction, where amino acids attack reducing sugars.
And that begins a cascade of reactions that Maillard, he mapped out. And they produce these large melanoid Compounds.
The interesting thing about that is that the Murchison meteorite is basically a very dry tar ball.
And the minerals are held together by this dark black tarry matrix.
And so in both the Miller Urey experiments and the Merchant meteorite, not only do we see amino and hydroxy acids produced, but we also see the next step in the reaction where the amino acids react with sugars and make these melanoid compounds.
So while the amino acids give you hope of a pathway to life, they are so reactive with the sugars that they're quickly consumed.
And in one of Miller's early papers, he actually took samples at frequent time intervals throughout the process. And you can see the amino acids build up, they plateau, and then they start going away.
And so right away, you know, not only are they being produced, but they're being consumed.
And as the gases get consumed and the amino acid production slows down, the consuming reactions take over.
[00:14:14] Speaker B: Yeah, so I've heard this kind of argument before, these results before, that the largest product, the greatest product of Muller Urey type experiments is actually tar.
But the Maillard reaction and these other molecules are being produced. Is that also like tar?
[00:14:33] Speaker A: Well, that's the first step.
[00:14:35] Speaker B: Okay.
And then pre tar precursor?
[00:14:39] Speaker A: Well, yeah.
[00:14:40] Speaker B: Well.
[00:14:43] Speaker A: It doesn't go completely to tar right away.
That takes some time.
Everybody is familiar with the Maillard reaction because you can see it in daily life, like when you're making a cheese pizza, that nice brown color on the crust of the cheese, that's the product of amino acids and sugars in the cheese reacting to form the brown crust. And likewise, when you're baking bread, if you want to get a nice brown crust on that, you coat it with some milk or cream, which has a reducing sugar in it, lactose, and that reacts with amino acids and in the wheat and the bread.
[00:15:34] Speaker B: So basically, we're cooking here. We're cooking.
[00:15:36] Speaker A: We are cooking.
[00:15:38] Speaker B: We're cooking the ingredients that are supposed to be being used to create life. And instead we're cooking them and producing something that is not leading towards life.
[00:15:47] Speaker A: I presume that's correct.
There's actually a symposium on the Maillard reaction, and it had two major themes. The one theme was the Maillard reaction and cooking.
And the other theme was the Maillard reaction in medicine.
Because when the amino acids and the protein in your eye react with an excess level of sugar, you generate cataracts.
And when you have lots of sugar loose in your blood, it can react with the proteins in your blood.
And this is a cause of arteriosclerosis so this one reaction, it makes great food and causes some serious medical problems.
[00:16:44] Speaker B: Yeah, well, I think this just speaks to the fragility of the molecules that are necessary for life. I mean, our cells have to work very hard to maintain an environment where the necessary biochemical reactions can go forward. You can create the building blocks you need and not have them be degrading. But without that cellular environment, all those molecular machines and all the processes that carefully maintain homeostasis, the life friendly environment, this is what happens. What you're talking about is sort of the natural progression.
So I guess people get very excited about amino acids being found in meteorites, amino acids being found in these Miller Year experiments, but that's not the end of the story.
And I guess the question is what's, you know, really, it's a case study in what happens when you have the building blocks of life but you don't have life.
What does it turn into? And it, if what you're saying, I understand it correctly, it doesn't progress towards life, it progresses towards substances that are very far removed from life.
[00:17:50] Speaker A: Yeah, that's correct. And they show.
When you're looking at a figure of abiogenesis, starting with the Miller Urey experiment and making amino acids and sugars and fatty acids and the nuclear basis for DNA and rna, they show arrows.
Taking these compounds individually, the amino acids make proteins and the fatty acids make lipids. And the nuclear bases, they make DNA and rna.
And that's a very nice idea, but that's not what happens. And the reason we know that's not what happens is if you go out into the environment and you look at like a swamp when organisms die and their cells lice, they release amino acids and sugars and fatty acids, all the things you need to build molecules or build cells, all those biomolecules.
But what do they do?
Do they spontaneously form new living organisms? No, they start reacting crosswise and you quickly get a buildup of melanoids.
These are the ultimate products of the Maillard reaction. And you can see it any day in the natural environment. This is what's going on. So we already know what happens next.
It's not what the people that are pushing abiogenesis want to happen.
In fact, it's the opposite.
[00:19:40] Speaker B: I love the example that you just gave. This reminds me of sort of the point that Jonathan Wells used to make. Obviously he passed away last year, but he would say, look, you could take a living cell, puncture it in a test tube. You now have all the components you need for a Cell. Everything you need is there, and yet you'll never form another cell. You're going to get basically degradation, exactly what you're talking about. But yet this is sort of like giving the origin of life its best chance. You're putting all the raw materials needed for a cell right there. They're right there. You know, in a swamp, you've got all this decaying biomatter, probably a steady stream supply of newly dead organisms that are resupplying, you know, undecayed biomatter. That's exactly what life supposedly needs to exist. And yet all it does is progress away from life. It never progresses back towards life. So I mean, just to like make sure, you know, this point is painfully clear for our listeners. The question is, on the early Earth where you've never had life, how are you going to move these biomolecules or these organic molecules towards life if you don't even have life to begin with?
I mean, what's going to happen, Ed? You're just going to have this sort of making amino acids and then these other reactions take place and eventually the end product is tar. Is that sort of what you would predict would happen on the early Earth if you had a steady stream of amino acids flowing in?
[00:21:05] Speaker A: Yeah.
If you just kept running the Miller Urey experiment for years or centuries, you're going to generate a lot of this melanoid compound and that's going to be your primary product.
There'll be a steady state concentration that's very low of amino acids and sugars and fatty acids and the nucleobases.
But you're not going to get the large biomolecules.
You're going to get the geomolecules that you find when you go into the natural environment and look at the diagenesis of organic matter.
[00:21:49] Speaker B: Yeah. Well, let's talk about that really quick.
And I don't know how much you've looked at this, but whether or not amino acids, these monomers, could link up into polymers. And I mean, I remember actually you talked about how Miller Urey experiments create this racemic mixture, which is an equal balance of left handed and, and right handed amino acids. I remember the first time that I learned about this concept of a race mixture was actually in a class I took from Jeffrey Beta when I was an undergraduate and he was talking to us about you could actually date dead organisms. Because initially when an organism dies, it's only using left hand amino acids. But over time, at a known sort of half life rate, those left hand amino acids will spontaneously revert to to right hand amino acids. And eventually you will end up in that dead decaying biomatter with a racemic mixture. And by measuring the proportion of left right handed, you could actually date dead biomatter. I remember Jeffrey Beta teaching our class about this when I was a student at UCSD and taking classes from him at Scripps. But this is a problem because if you want to link up these amino acids to form a protein, which of course that would be sort of the next step in the origin of life would be to try to grade these primitive peptides. Well, you've got this race pick mixture. So now you're linking up left handed and right hand amino acids. That obviously is not what life as we know it uses. Life only uses left hand amino acids. But from what I also understand, Ed, and maybe you can explain this. Sorry, this wasn't a question on the list of questions I gave you. But from what I understand, amino acids don't always link up in the same way where you're actually generating what we would call a peptide or protein. They can link them in different ways which yield biomolecules that are very far removed from biological proteins. Can you speak to this a little bit? What are some of the challenges faced, I guess is what I would say in linking up amino acids to form proteins?
[00:23:47] Speaker A: And you want that in two minutes, right?
[00:23:50] Speaker B: Well, no, I mean we're having a conversation, whatever you want to say.
[00:23:55] Speaker A: Amino acids, most of them have an amino group and a carboxylic acid group.
Some of them have a second amino group.
And these are called basic amino acids. And some of them are acidic, like aspartic acid that have two carboxylic acid groups. And so if you're building a protein biologically, you take the carboxylic acid that's on the alpha carbon and you react it with the amino group on another amino acid that's also on the alpha carbon. And you can build this long chain.
It's a very precise assembly.
And if you use only L, then these chains can coil uniformly.
If you throw in some D amino acids, you get kinks in that coil and that would hurt the protein functioning as an enzyme. The other thing is, if you're just putting things together randomly is you can have the wrong the terminal amino group on a basic amino acid react with the alpha carboxylic acid on another amino acid and you can form a branch.
And so instead of getting a linear chain, you can have multiple branches. And the same thing with the acidic amino acids they can form branches as well with the terminal functional group.
Now, in a regular protein, those terminal functional groups make the active sites.
But if they're consumed in the linear string of amino acids, you don't have those to give the protein its enzymatic function.
So not only is it hard to make that peptide bond that takes energy, but you have to put them all together the right way or you lose the chance of getting the functionality of that the enzyme needs.
[00:26:06] Speaker B: That was a pretty good explanation, Ed. That was probably less than two minutes and that was incredibly clear. And I've actually, I've heard this explained before, but the way you explained it was one of the clearest I've ever heard. You both get, basically you get these shapes of these peptides that don't coil the way a normal protein would, and you get these branches as well, which of course is not the way peptides or proteins in life are, are structured. And they can never function the way enzymes do in living organisms. Let me just, while I'm picking your brain here, Ed, I've also heard it said, and I think I remember learning about this when I was taking courses at UC San Diego as well, that when you link up two amino acids, that is a reaction that produces a water molecule.
And so if you think about Le Chatelier's principle, where a chemical reaction does not want to go forward in the presence of its products, okay? So if the polymerization reaction between two amino acids produces a water molecule, well, that reaction is never going to want to go forward in a water based environment.
You talked earlier about what was the environment on these, where the Murchison meteorite came from? Well, it sounds like they think that these amino acids there was some kind of a water based environment that, that help lead to their formation. Okay, fine. But that same environment is actually going to prevent the amino acids from linking up to form polymers because the polymerization reaction is never gonna wanna happen in a water based environment. Same goes for the quote unquote primordial soup. If this reaction was happening on the early earth, that's a water based environment. Water based environments are not where you want to have amino acids linking up to form polymers. So this problem I'm talking about, does this apply to sort of what you're talking about right now?
How would you form these primitive enzymes? And is there a solution for origin of life theorists or what are your thoughts on this?
[00:28:02] Speaker A: Well, in a biological system, the synthesis of proteins is driven by the cell's metabolism.
And you add leaving groups to make things couple together.
And it's all very carefully regulated so that they're put together properly when you're doing things randomly. Well, like you say, first off, the tendency in water is for peptide bonds to hydrolyze and break.
And so people start talking about, well, you've got a hot spring nearby, or you've got the sun drying out. And as the warm little pond becomes now a hot wet spot, you can drive these reactions together.
The problem being that as soon as it's hydrated again, either it rains or something, you're now in a situation where hydrolysis is the most common reaction and things are coming apart.
[00:29:08] Speaker B: So you're breaking them up again, basically.
[00:29:10] Speaker A: That's right.
[00:29:11] Speaker B: They're kind of like a bad relationship. They come together, but then they break up.
[00:29:15] Speaker A: Yes, all the time. And not only is it a bad relationship, but they're changing partners all the time.
And sometimes they get linked up with their sugar, and now they've gone really wrong.
[00:29:29] Speaker B: So it's a very, very unhappy relationship, basically. But, I mean, you talked about the possibility that in an environment where you could dry it out, maybe the idea, if I understand it right, is you could remove that water and then drive the polymerization reaction forward. And I've heard this talked about before. Maybe the primordial soup was splish splashing on the side of a volcano, that volcano was warm enough to allow things to dry out. And okay, fine. But it's always struck me that this now presents a new set of problems because heat also destroys these biological or these organic molecules, right? And they have half lives, and you actually want them to be there, to be less heat. Less heat tends to mean longer half lives, but more heat, the very heat you would need to dry these, these very, very, you know, primitive polymers out that also is going to have a destructive effect. Am I right in saying this, Ed? Or, you know, is there are. Are they sort of in like a damned if you do, damned if you don't situation here with regards to the heat needed?
[00:30:31] Speaker A: Yeah, well, the heat can also catalyze the hydrolysis faster.
It's heat. But you got to get rid of the water.
And if the heat is still there and your water's still there, you're racemizing the amino acids faster.
So any reaction that may have sorted the Ds from the Ls is now getting undone.
All of these ideas try and lead to plausible schemes.
They introduce new problems, as you just said.
[00:31:08] Speaker C: That was recently retired chemist and researcher Ed Peltzer discussing the fragility of life at the biochemical level, explaining how just having life friendly chemicals does not automatically result in life.
A lot of hype comes out of origin of life studies as they claim to be getting closer to elucidating the origin of life or creating life synthetically in a lab. But as Peltzer has explained, the challenges are sobering indeed.
Now, don't miss the second half of this discussion. In Part two, Peltzer will discuss the problems associated with the RNA world hypothesis, the debate over the early Earth conditions, and he even shares his own personal story of being censored and almost canceled during his long career as a researcher.
That's all in Part two, so look out for that in a separate episode for ID the Future. I'm Andrew McDermott. Thanks for joining us.
[00:32:02] Speaker B: Visit
[email protected] and intelligent design.org this program is copyright Discovery Institute and recorded by its center for Science and Culture.
