So there are really two questions. The first question is can researchers use directed evolution experiments to improve the catalytic properties of the ribozymes to such a degree that it is able to reproduce itself? The second question is can a self reproducing ribozyme achieve an error rate that is low enough to enable some populations of ribozymes to achieve and maintain Darwinian advantage over other populations?
Now as an inventor I have a very optimistic viewpoint of what creative people can achieve, so Iâm am willing to concede the first point as a real possibility, even though it seems pretty far out of reach at present the article you provided suggests that it might not be impossible. However it is the second question that I think presents the real challenge to the RNA world hypothesis. I think that if a truly self reproducing ribozyme is ever developed, that it is likely that after a few rounds of reproduction the reproductive process would ground to a halt. The author of the first paper that I mentioned also considers the low fidelity problem to be possible fatal to the RNA world:
These errors would be critical to the prospects of molecular evolution, since there is a threshold error rate above which a replicating molecule loses any Darwinian advantage over the rest of the population â in other words, evolution depends on good enough replication. Fidelity of copying could thus be a problem, hitherto insufficiently recognised, for the appearance of a self-sustaining, evolving RNA-based system: that is, for an RNA world.
Maybe this obstacle could have been overcome in time. But my hunch is that any prebiotic molecule will have been too inefficient, inaccurate, dilute and noise-ridden to have cleared the hurdle.
While I donât see an evolutionary solution to this issue, I think that from a strictly engineering perspective an artificial riboorganism would need an error correcting mechanism in order to reproduce continuously, like organism do. Perhaps one can be engineered using similar methods as was used to create error correction for reverse transcription in the paper below:
It looks to me like a case of the product of polymerization being critical for the fitness of the polymerase.
When researchers select RNA polymerase ribozymes only for their ability to copy a template at a higher rate, with little to no concern for the accuracy of replication, that is, where the function of the product of template copying does not in turn contribute to the fitness of the polymerase ribozyme, then there is effectively no selection pressure to improve or even maintain any level of copying fidelity.
For a real evolving organism, the replicated genes have functions that in turn contribute to the fitness of the organism that reproduces, such that if the replication machinery makes too many errors the mean fitness of the offspring is reduced in comparison. Reduced mean fitness => lose in competition to dominate the population. Thatâs normally how selection pressures can change mutation rates in real biology, where the competing organismâs offspring mean fitness is tied to the accuracy of replication. Over time, mean fitness of carriers of mutations that affect the mutation rate would determine how mutation rates would evolve in the future.
This does of course raise questions about how a higher copying fidelity would emerge initially in an RNA world, but what we can say is that in so far as a replicase with copying ability (whether a single molecule or a small community of cooperators) arose at all, itâs fidelity would immediately be a component of selection in a way it has not been in the experiments described above, since itâs ability to reduce the rate of deleterious mutations would be directly tied to itâs offspringâs survival and reproductive capacity.
So if we think about what sort of ribozymes could actually exist and function in a RNA world it seems me that the very first thing one would need to do is study how well ribozymes function without cytosine. One paper that attempts to do this conceptually can be found on the link below:
If we take the short chemical half life of any cytosine generated in the warm oceans of the Archean, and the lack of cytosine in meteors, then one must acknowledge that ribozymes taken from nature that rely on 4 RNA nucleobases, do not represent chemistries that would be possible in a hypothetical RNA world. So chemists would have to first engineer alternative molecules that are capable of analogous processes accomplished by observable ribozymes while just using three bases first. Then it would necessary to demonstrate that those compounds could last long enough to reproduce, and be capable of guided evolution.
Current experiments that attempt to use guided evolution to engineer riboorganisms by using RNA enzymes that are taken from living cells, are using templates that are not demonstrably able to exist without cells that function in much the same way as modern cells do, and are thus examining how to use current biology to engineer alternative biologies, as opposed to studying how the raw materials available in nature could have been the basis for an RNA world on the early earth.
Yes in concert with DNA based enzymes such as RNA polymerase and aaRS enzymes, very little is possible without those DNA based enzymes. The above is assuming ideal conditions if we start to take in consideration the actual environmental conditions the situation deteriorates much more for RNA world speculations.
It seems weâve entered the mere assertion-phase of this discussion. Can you please show how you know what is possible? It would seem - taking your statements at face value - that you have some sort of inside knowledge of possible chemistries, that a large swath of chemists and biochemists are not aware of. Where did you obtain this knowledge?
I think we have to be really careful when we think about the chemistry here. Remember that chemistry is controlled by the collisions of reacting molecules, and molecules are constantly colliding. Chemical reactions are controlled by kinetics and thermodynamics:
Thermodynamically, when given time to equilibrate reactions will favor the more stable (lowest energy) products. This is most often what we study in the lab. However highly disfavored reactions still happen because reactions are random collisions which means the product we report is just the statistically most likely product, not exclusively the only product. On top of this, chemical reactions in nature can often be non-equilibrium which means that unexpected things can happen and products that would normally be favored might not be under different, and potentially temporary, conditions.
Kinetics describes how quickly a reaction occurs and depends primarily on the activation energy (the energetic hill a reaction has to get over in order to form a product) and temperature. Catalysts speed up a reaction by lowering the activation energy but donât change the products. Enzymes are biological catalysts and itâs important (I think) to remember that in general catalysts are not required for a reaction to work, but they may be required for a reaction to work efficiently or on timescales we study. I have no doubt that some biological reactions that people assume enzymes are necessary for are not necessary at all if you wait long enough.
From the article you cited:
However, the rapid deamination of C to U and the absence of C in meteorite samples suggest that prebiotic RNA may have been deficient in cytosine.
Deficient is not absent.
These problems do not rule out the possibility of an RNA World based on AUG, but they show that it would be significantly more difficult than with a four-base alphabet.
Difficult is not impossible.
I think itâs clear at this point that we are way too early into understanding what chemistries may have been like in the beginning to make any conclusions about abiogenesis. And even if we find plausible chemical routes to the first cell, it doesnât mean it happened and I doubt weâll find conclusive evidence. As a chemist itâs a really interesting and challenging question. OoL really stretches the imagination as a scientist.
But as a Christian Iâm not hung up on whether God âpoofedâ the first cell into existence or nudged some molecules in the right direction, or just watched nature work the way he created it to work. Nobody knows the answer to how precisely how the first living thing got here, so we should be open to possibilities and eager to let science do its thing. That doesnât exclude theological explanations and explorations, as I think GAE showed pretty well. We can interweave multiple layers of understanding without trying to force them onto each other.
By the way, aminoacylating ribozymes are known. Some can even self-aminoacylate. aaRS enzymes donât appear to be strictly needed for charging tRNA with amino acids. The smallest known ribozyme catalyst of aminoacylation is 5 nucleotides long.
Letâs first define the difference between an evidence based conclusion versus a false assertion. If we treat the RNA hypothesis as a historical fact we are making a false assertion, if we treat as a hypothesis then concluding that the evidence doesnât support its historicity that isnât a false assertion, especially if one has evidence to support oneâs statements.
If we look at nature, our RBCs function without using RNA polymerase and the aaRS, however their simplicity is the result a complicated process inside a multicellular organism. Similarly, one can find very simple cells living inside other cells as obligate intercellular parasites, so in nature extreme simplicity in a cell seems to depend on itâs environment taking over the processes of life support for it, and the best examples that I know of exist inside a more complex living system. What is being proposed by OOL researchers are free living cells that are not only much simpler than our red blood cells but are formed using simpler processes. That appears to be a really tough engineering challenge, sort of like artificial low mass controlled nuclear fusion (accomplished without the mass of a star) it might be possible to engineer, but there really isnât evidence such a process can arise in nature due to physics and chemistry. So now I will justify that statement.
First we do not have scientific evidence that RNA can arise naturally in any environment except a modern cell or the laboratories of highly skilled chemists. While some ribose has been found in comets, adenine, guanine , cytosine, and thymine have not been. What is more only three of those nucleosides have been found in meteors cytosine hasnât.
What is more theses nucleosides do not readily attach to ribose simply due to proximity. Rather as explained by James Tour the ability of natural processes to join these nucleosides to ribose without a modern cell also hasnât been in anyway demonstrated to be possible, without the skillful intervention of synthetic chemists. As he explained in the article linked below:
So in a pre cellular world what we actually would have are racemic mixtures of amino acids, three out four nucleosides that needed to make stable RNA, and racemic mixtures of ribose, arabinose, xylose, and other pentose sugars also in minute concentrations entering a global ocean of unknown pH over large areas. How does that situation lead to RNA, much less ribozymes and riboorganisms? An honest answer is that know one has ever demonstrated the existence of any process in which chemistry and physics alone can cause the above to form into RNA, ribozymes much less a cell, so to assert that it definitely happened spontaneously would be a false assertion. However there are many reasons not to think it is possible, here are a few less complicated ones.
One if we put aside all biases the evidence that the earth spent over a billion years as a water world without dry land seems to be growing stronger all of the time. As explained in the article below:
So how exactly could biopolymers that form due to cycles of wetting and drying form in the middle of a ocean without dry land?
How does the inability of black smoker vents to build methanethiol, as demonstrated by direct analysis impact the plausibility of the metabolism first hypotheses?
Lipids bilayers can form in bench models of alkaline deep sea vents at temperatures above 60 C and a pH of 11 to 12. However such temperatures and pHs would dissolve RNA which is most stable at an acidic pH. So did RNA end up inside a phospholipid bilayer, without DNA derived enzymes, and proteins? And how did those proteins form outside of a cell in the middle of an global ocean without the process dehydration synthesis?
I could list many more of problems with the concepts as questions that demonstrate that the problems with OOL speculations are serious with some of them even being somewhat obvious such as the ones I mentioned, while others are so nuanced that I would rather let professional chemists and physicists such as James Tour, and Stephen Miller pose them but Iâm sure that you have read their papers so I would rather pose the questions that I understand, In any event I am not making false assertions (at least based on the available evidence). If you disagree please use this post to demonstrate that I am.
Yes. And itâs a fact that you have no evidence that cytosine canât arise outside of the context of life as we know it. All you have is two things: Cytosine isnât found in comets(so what? Can life or RNA only arise if cytosine is presently found in comets?), and has a shorter half-life than the other nucleobases. How does it follow from this that cytosine did not exist in the prebiotic environment at some point? Please explain that to me in as much detail as possible.
Sure. But it is also a false assertion to say there is no evidence that there was an RNA world.
First of all, logically speaking, in so far as there has to be some solution to the chicken-and-egg paradox concerning the relationship between DNA as a relatively inert information storage molecule, and proteins as the so-called workhorses of biochemistry, the fact alone that RNA is capable of serving both information storage and catalytic roles lends itself as an obvious candidate.
But not only that, the fact that it performs that very role in protein biosynthesis canât just be ignored.
The ribosome being a universally conserved ribozyme, RNA being an intermediate in translation, the role of tRNA in the same, and that all the individual steps necessary for translation can be performed by RNA alone would seem an absurd coincidence, that RNA is prior to DNA in the pathways of nucleotide biosynthesis(biosynthesis of deoxyribonucleotides is by reduction of ribonucleotides, implying that DNA biosynthesis is an evolutionary elaboration on the pathways to RNA biosynthesis, and DNA therefore came chronologically later), and the widespread use of nucleotide cofactors in enzymes functioning in central metabolism is all data best explained by there having once been an RNA world.
We donât have to know how that RNA world arose to be able to say that there really is evidence it existed, and that extant life appears to have evolved from some RNA-world like state, even if many aspects of the nature of this RNA world are still unknown.
But you have no such evidence. All you have are assertions and appeals to ignorance. Things you donât know compel no conclusion other than the conclusion that your lack of knowledge.
Iâll take all of that as commentary. Nothing follows from any of that.
Not really true. There is no in-principle barrier preventing any synthetic experiment in abiotic chemistry from occurring in nature. At best what you can say is it would seem very unlikely for some particular synthetic route of chemistry to occur given some set of assumptions about what a pre-biotic environment might have looked like, but such arguments are only as good as the assumptions you make about the pre-biotic environment.
But thereâs a more important point to make here: At any given moment in history there was something we didnât know how could happen in nature, and then a later time when someone found out. This kind of âno one have shown how Xâ is not compelling evidence for anyting unless you can say that youâve actually tried all(or a very substantial fraction of) plausible naturally arising pre-biotic environments.
And we have not. Not by a long shot.
The truth is that we human beings have next to no idea of just what kind of chemistry is really possible, and new discoveries are made all the time. Nobody knows and nobody is able to predict the long-term behavior of complex bulk solutions. The longest running wet-dry cycle experiment in history ran for something like 30-ish cycles. It tested only one specific setting. Nobody knows what would have happened with a different mix of chemicals, or another million cycles with intermittent replenishment.
You donât know. James Tour doesnât know. Nobody knows. Because the conditions become so complex so fast they canât even be simulated on computers.
This is all based on the assumption that ribose and the nitrogenous bases were synthesized individually and then had to join up through that glycosidic bond. Do they have to? Is that the only route to RNA? How do you know? And what do you really know about what conditions favor these reactions?
Bzzt. Stop. Now youâre claiming to know what we would have in a pre-cellular world. Please describe to me this pre-cellular world, and how you know it was like you think it is, and then tell me how you can predict from first principles what kind of chemistry occurs in this pre-biotic world. Sounds like you need to start lecturing on planetary astronomy and geochemistry with this remarkable insight you have. Just where did you get it?
I accept that confession to ignorance. Fine, nothing wrong with that. But when we donât know, we investigate. You sound like youâre desperate to quit.
No one has ever demonstrated that the scenario you describe would have to.
At any given moment in science there is some advancing frontier of research, where certain topics are hotly contested, and in those moments you can find statements by people on different sides arguing that the views of their opposition are somehow all unlikely, implausible, or impossible. Yet such debates usually eventually settle, and one side comes out being right and the other side wrong. You can go pick quotes from the period when the mechanism of oxidative phosphorylation was unknown and a subject of hot contest, to âproveâ that (taking the arguments from both camps) life must be impossible , because apparently thereâs no way any mechanism of oxidative phosphorylation could possibly occur and suffice to power life. But one side won that debate eventually, and the other side lost, and we now know ATP is generated by chemiosmosis.
You can find lots of papers arguing that âthe other guyâs scenario for the RNA world is wrong and hereâs whyâ, itâs just that itâs all based on innumerable assumptions that have yet to be settled(some argue there was no dry land at all, not even volcanoes of any appreciable size, which would basically rule out all versions that involve evaporation and wet-dry cycles, leaving only submarine hydrothermal vents among presently conceived settings for lifeâs emergence), and are likely to remain unknowns for quite a while, because thereâs scant little evidence for what the earliest periods in Earthâs history was really like.
This is exactly what youâre doing now.
Which particular metabolism-first hypothesis? There are dusins.
At what rate? At what rate is it synthesized? Whatâs the equilibrium concentration? In what specific microenvironment? How long does that state last? For any given answer you provide to each of these questions, how did you determine these are the correct assumptions to make?
Good question, we donât know. Do you? Guess we need to investigate.
Who says they did? Are they required to? How do you know?
Do you have a point? The fact that currently, they work with non-ribozymes is completely irrelevant to the point, which is that such relics were predicted by the RNA World hypothesis. âDNA based enzymesâ makes no sense.
So, Geremy, what hypothesis so you have that explains the stone-cold fact that the enzyme at the center of protein synthesis is a ribozyme?
The brain trust of ID creationism canât help you with this, as they simply misrepresent this factâno interpretation involved.
In science, neither is relevant. We test hypotheses.
Agreed.
We donât. We test its empirical predictions. Pseudoscientists use language like yours and refuse to test their hypotheses.
Unfortunately testing hypotheses costs money, at present I can only afford to test hypotheses that are related to increasing the efficiency of emergency generators, since that the area that my present invention is related to, which I am turning into a business enterprise which of course takes up a lot of time. I do spend way too much time comparing the predictions of origin of life and evolutionary theorists, to the evidence from the embryology, chemistry etc.
Youâre not evaluating any evidence. Youâre looking at rhetoric and only claiming expertise for those who say things you wish were true.
Yeah right, I do no such thing, Iâve read whole books by authors as diverse as Eugene Kooninâs âThe Logic of Chanceâ, and Ernst Haeckelâs âThe Riddles of the Universe in the End of the Nineteenth Centuryâ, to Micheal Dentonâs The Miracle of the Cell", along with countless papers on the subject. Your statement only reveals your false presumptions about me.
Such as? Why wouldnât you view the experts who actually do the research as experts? Has Tour tested any abiogenesis hypothesis?
When I read any paper I save it in my computer and then I read, the papers in their references. For example here is a paper by Brian Miller and Jeremy England:
It piqued my interest in what Jeremy Englandâs work actually is so I read his paper about where he made catalytic sets use salt crystals, and I started watching his interviews on you tube etc. where he explained his work.
As far as James Tour is concerned James Tour is a synthetic chemist, and a chemical engineer, that is expertise. After reading his papers in Inference, it helped me to understand that many famous OOL researchers such as Albert Eschenmoser, and Nick Lane who have written so much about the origin of life are also very good chemical engineers, and synthetic chemists, that is their expertise. Of course that doesnât make them experts on the origin of life any more than than Tour is, because the are not studying what happens in plausible early earth conditions without a highly motivated intelligent agent, rather they are laying the groundwork for more advanced synthetic biology experiments in the future.
No, but them having actually studied biology and the methods of historical inference in biology makes them more qualified to say something about what kind of problem it is that needs to be solved. Several of Tourâs objections are crappy because Tour appears to have no understanding of the history of life on Earth. An example I like to bring up is that Tour seems obsessed with pointing to the structures and molecules found in eukaryotes as things the origin of life field need to explain, in total ignorance of the fact that eukaryotes evolved at least 2 billion years later than lifeâs origins. Another point is Tour appears to have no familiarity with the field he criticizes when he invokes the argument that early primitive cells couldnât function without complex membrane transport proteins because modern phospholipid bilayers are impermeable. Hey, Tour, you in there? Nobody thinks the first cell-membranes were made of phospholipids.
This is the âyou canât study anything in a lab without being in the labâ-argument. The worst of all creationist arguments. What are the researchers supposed to do here, step out of the laboratory and wait for a volcano or hydrothermal field to spontaneously form in the fume hood?
Obviously the researchers have to set up some sort of analogue or facsimile of the environment they are positing could produce phenomena of interest, as the laboratory setting is just not the kind of environment in which these geological phenomena naturally arise. You wonât be surprised to discover that thunderstorms donât spontaneously occur in the average wetlab. But can we all agree that volcanoes and hydrothermal vents exist, and that nobody had to walk out into the field and create them? And thunderstorms are a real thing that happens âout thereâ in the world?
Since you canât study those environments out in nature outside of the influence of the life that already exists everywhere on Earth, you have to try to synthetically reconstruct the setting in the laboratory so you can understand itâs behavior in the absence of extant biology. Blathering that someone had to use tubes and flasks, and a computer, and had to buy the chemicals off the shelf to start these experiments, is inane.
Well there was no scientific evidence that ribose could arise naturally in any environment except a modern cell or chemistry laboratory until it was found in meteorites. There was no cozy cellular environment, neither were there laboratories equipped with batch reactors, flasks, incubators etcetera yet ribose formed in those meteorites (the oldest ones, for that matter).
Do you know the amount of biochemistry a modern cell must accomplish to get activated ribose, yet ribose formed in meteorites without all of the enzymes present in modern cells. Look at the pentose phosphate pathway below which is the mechanism of ribose-5-phosphate generation in cells like ours. The pathway has two phases, one oxidative and the other non-oxidative: ribose (with an attached phosphate) is formed in the non-oxidative phase.
The first graphic shows the oxidative phase and it ends with ribulose-5-phosphate. Ribulose-5-phosphate is changed to ribose-5-phosphate in the non-oxidative phase as shown in the second graphic. Each arrow represents a chemical reaction catalyzed by an enzyme.
Surely, whatever physical conditions were present on those meteorites and others which travel through space were sufficient to drive ribose synthesis without the aid of enzymes or the equipment and reagents available to chemists. This indicates you are baselessly underestimating the ability of natural processes.
Not even close, and even if true, it would not justify your misrepresentation of the scientific method as not including hypothesis testing.
Testing personal hypotheses is a great way to guide oneâs personal search through the literature. It costs $0 to articulate an empirical test anyway. What are you waiting for?
I donât see any evidence of your engagement with any such evidence.
Has Brian Miller done any relevant work in the field?
He has none testing abiogenesis or early evolutionary hypotheses. Can you show me where Tour has addressed metabolism-first hypotheses, even rhetorically?
No. Nick Laneâs relevant expertise and experience is far, far broader than Tourâs. Heâs neither a chemical engineer nor a synthetic chemist, as you would know if you had read any of his papers:
Of course, their work does. As I said, youâre not looking at evidence, just rhetoric.
You seem to not understand that working backward from what we have now is just as, if not more, important as starting from scratch.
Not even close, and even if true, it would not justify your misrepresentation of the scientific method as not including hypothesis testing.
Where did I say any such thing if you create arguments that I did not make and then attack them that is simply creating and attacking a strawman. All I said is that hypothesis testing costs money, which is true, unless technicians will work for free, and chemical kits and lab equipment are free. This wasnât an argument against the validity of hypothesis testing, only an acknowledgment that If I were to use my personal resources researching the OOL, it would require a significant expenditure of personal funds.
Testing personal hypotheses is a great way to guide oneâs personal search through the literature. It costs $0 to articulate an empirical test anyway. What are you waiting for?
My position with the origin of life is simple, people who do not know how to construct a cell from the naturally occurring chemicals taken from the earth, or even synthesized in a laboratory are not experts on how cells came to be, aka the origin of life, so there are no human experts on the origin of life on earth. One may be an expert at many other things: evolutionary biology, geochemistry, planetary science etc, but we should be honest about our ignorance, and our knowledge.
I think that a better methodology to gain a better understanding of the actual constraints on constructing cells at the OOL, would be for OOL researchers to dedicate their time and expertise into trying to understand how to build and assemble the component parts of living observable cells. This would have countless side benefits for medicine and biotechnology and would create actual experts on how to construct and assemble cells from the ground up, an expertise that does not exist at present.
I donât see any evidence of your engagement with any such evidence.
Everyone is entitled to their opinion, letâs talk a little moreâŚ
Has Brian Miller done any relevant work in the field?
Does he pretend that he knows how to make cells from scratch? No, does he take a deep dive into the physics of some models of abiogenesis proposed by those who proposed models of abiogenesis? Yes, many OOL theorists seem pretty convinced that the cells that we can not study because they lived in the distant past survived just fine without the very mechanisms that are essential to the survival of cells today, but surely the lack of enzymes would slow down the chemical reactions of a cell to the point that it would be essentially dependent on the environment to do the work of that the enzymes were doing. Of course he isnât the only one who does this ATP motors, DNA, that cells could exist the mechanisms that allow them to exist so all that Miller does is discusses with them the implications of those models of biology. For example in the paper that I attached earlier
Miller writes:
Enzymes are essential for energetically favorable reactions since most reactions are too slow to drive cellular operations. Enzymes accelerate the reactionsâ turnover rates by factors typically between 10^8 and 10^10, and the increase in many cases is significantly higher.59. Without enzymes, the concentration of a substrate would typically need to be millions of times greater to maintain a comparable reaction rate. This is not a plausible scenario.
The statement that âenzymes are essential for energetically favorable reactions since most reactions are too slow to drive cellular operationsâ, is imminently falsifiable, so the best way for you to demonstrate that Miller has nothing to contribute to the conversation is to simply find an example in nature of a cell that survive without using enzymes, without such a discovery it seems to be a valid hypothesis that cells need enzymes to function, if one is interested in looking at the evidence instead of rhetoric.
He has none testing abiogenesis or early evolutionary hypotheses. Can you show me where Tour has addressed metabolism-first hypotheses, even rhetorically?
No, I donât know of him specifically addressing metabolism first hypotheses, but others have who believe in unguided abiogenesis have :
No. Nick Laneâs relevant expertise and experience is far, far broader than Tourâs. Heâs neither a chemical engineer nor a synthetic chemist, as you would know if you had read any of his papers:
Yes, Nick Lane is a biochemist with a profound understanding of metabolism, who I think actually helped advance the OOL speculations toward scientific rigor by falsifying the various organic soup hypotheses. He is also an evolutionary biologist, who is very good at designing environments that can make lipid bubbles, so while he may not be an engineer on paper in reality he thinks like an engineer which is a good thing from my standpoint not enough evolutionary biologists think like engineers which is just an observation that I have made reading papers written by evolutionary biologists of all stripes. When I first read his papers the very first thing that it made me do was investigate actual alkaline deep sea vents in nature, which led me to papers such this one:
To his credit Lane took such criticism in stride and began building bench models of alkaline deep sea vents, which actually make lipid bubbles at 70 C and high pHs. There are some interesting similarities between the chemistry of alkaline deep sea vents and the redox reactions that occur in biology. The experiment related to his work which I found most interesting actually demonstrated carbon fixation by a bench model alkaline deep when there was a large pH gradient between the simulated ocean water and the vent. I linked it below:
Of course metabolism is not life, any more than life is genetic sequences, proteins, or any other component of a cell. Lane and others who support the alkaline vent hypothesis should select an archaea that lives near an alkaline sea vent at present, genetically engineer to not make enough itâs own ATP to survive on its own, (much like Rickettsia and Chlamydia) and, then try various permutations of the alkaline vent environment to demonstrate that the alkaline vent can replace ATP in a cell just like a host organism can for a parasite, that would be a proof of concept that the alkaline sea vent can actually power cells, which hasnât been done or you can correct me if Iâm wrong even attempted as of yet.
Finally, like most OOL theorists Lane hasnât really addressed the problem of cell assembly. While many of these basic building blocks of cells can be explained by self ordering processes and natural law, the actual creation of cells has not been, instead the current explanations This still leaves the problem mentioned in the paper linked below:
Of course, their work does. As I said, youâre not looking at evidence, just rhetoric.
Again what evidence? All of the evidence we have available demonstrates that cells make cells, while extracellular environments donât. Be that as it may if you can provide evidence that a single environment can generate all of the chemistry of a cell I would be happy to look at it. If you could demonstrate the existence of a cell that reproduces without DNA I would look at that too. Since none of the above is in evidence there really isnât any evidence that cells can be naturally generated by something other than a preexisting cell.
