F Rosa Rubicondior: Abiogenesis News - That God-Shaped Gap Just Keeps On Shrinking

Friday 1 March 2024

Abiogenesis News - That God-Shaped Gap Just Keeps On Shrinking


Scripps Research scientists reveal how first cells could have formed on Earth | Scripps Research

It's been a bad week so far for creationists. Coming so soon after scientist announced they had solved the 'chirality problem, is news that another team have shown how simple cells could plausibly have formed in the pre-biotic conditions that pertained on early Earth.

Creationists are generally black & white thinkers who value certainty above truth, so, for them there is no such thing as a plausible explanation; either something is proven beyond doubt, even passing an especially impossible standard of evidence, or it is wrong (so God did it!).

And one of their 'certainties' is their absolute faith in the slogan, "You can't get life from non-life!", which is chanted like a protective mantra in any debate about evolution (conveniently switching the debate from evolution to what they think is safer ground, abiogenesis). But ask them to define 'life' in such a way that you can test for it to tell if something is alive or not, or to explain how the non-living food they eat gets converted into living tissues, if that's impossible, and you're likely to get an ad hominem or an indignant, condescending flounce and a swift termination of the conversation.

It is an essential ingredient of creationism that the belief that abiogenesis is 'impossible' be maintained as the last refuge for their ever-shrinking creator god to be located in, as all the other gaps are closed to it.

So, having committed themselves to the certainty that abiogenesis is 'impossible', they have unwittingly committed themselves to accepting that any plausible process which can be shown to be viable, refutes the notion of impossibility and everything they conclude from it. So, their next step is the intellectually bankrupt technique of moving the goal-posts or demanding scientist provide an impossible standard of evidence such as showing it happening - billions of years ago. Never will they concede that evidence of plausibility refutes the claim of impossibility because, to a black & white thinker, plausibility doesn't give enough certainty, so can be dismissed until proven.

So, we can expect that predictable display of intellectual bankruptcy in response to the news that scientists at the Scripps Institute, La Jolla, CA, USA have discovered a plausible mechanism for the formation of simple self-replicating cells in the prebiotic conditions that pertained on early Earth.

Their findings are published in the Cell Press journal Chem and are the subject of a Cripps Institute press release:
Scripps Research scientists reveal how first cells could have formed on Earth

New phospholipid discovery brings researchers closer to understanding how primordial cells emerged during origin of life.

Roughly 4 billion years ago, Earth was developing conditions suitable for life. Origin-of-life scientists often wonder if the type of chemistry found on the early Earth was similar to what life requires today. They know that spherical collections of fats, called protocells, were the precursor to cells during this emergence of life. But how did simple protocells first arise and diversify to eventually lead to life on Earth?

Now, Scripps Research scientists have discovered one plausible pathway for how protocells may have first formed and chemically progressed to allow for a diversity of functions.

The findings, published online on February 29, 2024, in the journal Chem, suggest that a chemical process called phosphorylation (where phosphate groups are added to the molecule) may have occurred earlier than previously expected. This would lead to more structurally complex, double chained protocells capable of harboring chemical reactions and dividing with a diverse range of functionalities. By revealing how protocells formed, scientists can better understand how early evolution could have taken place.

At some point, we all wonder where we came from. We’ve now discovered a plausible way that phosphates could have been incorporated into cell-like structures earlier than previously thought, which lays the building blocks for life. This finding helps us better understand the chemical environments of early Earth so we can uncover the origins of life and how life can evolve on early Earth.

Professor Dr. Ramanarayanan Krishnamurthy, PhD, co-corresponding senior author.
Department of Chemistry
The Scripps Research Institute, La Jolla, CA, USA.
Krishnamurthy and his team study how chemical processes occurred to cause the simple chemicals and formations that were present before the emergence of life in prebiotic Earth. Krishnamurthy is also a co-leader of a NASA initiative investigating how life emerged from these early environments.
Vesicles within the protocell-like structure.
Credit: Scripps Research
In this study, Krishnamurthy and his team collaborated with the lab of soft matter biophysicist Ashok Deniz, PhD, co-corresponding senior author and professor in the Department of Integrative Structural and Computational Biology at Scripps Research. They sought to examine if phosphates may have been involved during the formation of protocells. Phosphates are present in nearly every chemical reaction in the body, so Krishnamurthy suspected they may have been present earlier than previously believed.

Scientists thought protocells formed from fatty acids, but it was unclear how protocells transitioned from a single chain to a double chain of phosphates, which is what allows them to be more stable and harbor chemical reactions.

The scientists wanted to mimic plausible prebiotic conditions—the environments that existed prior to the emergence of life. They first identified three likely mixtures of chemicals that could potentially create vesicles, spherical structures of lipids similar to protocells. The chemicals used included fatty acids and glycerol (a common byproduct of soap production that may have existed during early Earth). Next, they observed the reactions of these mixtures and added additional chemicals to create new mixtures. These solutions were cooled and heated on repeat overnight with some shaking to promote chemical reactions.

They then used fluorescent dyes to inspect the mixtures and judge if vesicle formation had taken place. In certain cases, the researchers also varied the pH and the ratios of the components to better understand how these factors impacted vesicle formation. They also looked at the effect of metal ions and temperature on the stability of the vesicles.

The vesicles were able to transition from a fatty acid environment to a phospholipid environment during our experiments, suggesting a similar chemical environment could have existed 4 billion years ago.

Dr. Sunil Pulletikurti, first author. Department of Chemistry
The Scripps Research Institute, La Jolla, CA, USA.
It turns out that fatty acids and glycerol may have undergone phosphorylation to create that more stable, double chain structure. In particular, glycerol derived fatty acid esters may have led to vesicles with different tolerances to metal ions, temperatures, and pH—a critical step in diversifying evolution.

We’ve discovered one plausible pathway for how phospholipids could have emerged during this chemical evolutionary process. It’s exciting to uncover how early chemistries may have transitioned to allow for life on Earth. Our findings also hint at a wealth of intriguing physics that may have played key functional roles along the way to modern cells.

Professor Ashok A. Deniz, co-author
Department of Integrative Structural and Computational Biology
The Scripps Research Institute, La Jolla, CA, USA.
Next, the scientists plan to examine why some of the vesicles fused while others divided to better understand the dynamic processes of protocells.

Authors of the study, “Experimentally Modeling the Emergence of Prebiotically Plausible Phospholipid Vesicles” include Sunil Pulletikurti, Veena S. Kollery, Mahipal Yadav, Ashok A. Deniz, and Ramanarayanan Krishnamurthy of Scripps Research.
Sadly, the research paper is behind a paywall, but some technical detail is included in the abstract:
Graphical abstract
Highlights
  • Emergence of phospholipid-protocells in the context of chemical origins of life
  • Transition from fatty acids to phospholipid-based vesicles via cyclic-phospholipids
  • Heterogeneous vesicle compositions and morphologies stable to a range of conditions
  • Emergence of 1,2-diacylglycerol protocell-compositions coincidental with biology

Summary

The prebiotic emergence of protocells is an important part of any origins of life scenario. Although fatty-acid-based vesicles are well studied, how they transitioned to phospholipid vesicles is uncertain. Herein, we show that cyclic-phospholipids formed from fatty acids and glycerol could have played a role by generating a heterogeneous library of vesicles with diverse morphologies and tolerance to a range of metal ions, temperature, and pH. The cyclic phosphate moiety facilitates the natural emergence of vesicles composed of diacyl-phospholipids to become part of the chemical evolutionary process. Competing emergent properties of the various systems (facilitated by additives) could have led to an early preference of the sn-1,2-acyl-substitution on the glycerol backbone coincidental with extant biology. Thus, cyclic-phospholipids could have played a significant role not only in early prebiotic protocellular chemistry but also in facilitating the chemical evolution of protocells from the structurally simple to the functionally more complex.

So, the last refuge of Creationism's ever-shrinking little god is getting smaller and smaller. This means creationists frauds will need a special effort to try to misrepresent the science or discredit the scientists, so standby for a display of sanctimonious false witnessing as creationists try to cling to the flotsam from the wreck of their sinking ship.
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