New computational model of chemical building blocks may help explain the origins of life

August 24, 2017
Ken Dill explains the computational model that shows how certain molecules fold and bind together in the evolution of chemistry into biology, a key step to explain the origins of life. Credit: Stony Brook University

Scientists have yet to understand and explain how life's informational molecules – proteins and DNA and RNA – arose from simpler chemicals when life on earth emerged some four billion years ago. Now a research team from the Stony Brook University Laufer Center for Physical and Quantitative Biology and the Lawrence Berkeley National Laboratory believe they have the answer. They developed a computational model explaining how certain molecules fold and bind together to grow longer and more complex, leading from simple chemicals to primitive biological molecules. The findings are reported early online in PNAS .

Previously scientists learned that the early earth likely contained the basic building blocks, and sustained spontaneous chemical reactions that could string together short chains of chemical units. But it has remained a mystery what actions could then prompt short chemical chains to develop into much longer chains that can encode useful protein information. The new may help explain that gap in the evolution of chemistry into biology.

"We created a computational model that illustrates a fold-and-catalyze mechanism that amplifies polymer sequences and leads to runaway improvements in the polymers," said Ken Dill, lead author, Distinguished Professor and Director of the Laufer Center. "The theoretical study helps to understand a missing link in the evolution of chemistry into biology and how a population of molecular could, over time, result in the emergence of catalytic sequences essential to biological life."

In the paper, titled "The Foldamer Hypothesis for the growth and sequence-differentiation of prebiotic polymers," the researchers used computer simulations to study how random sequences of water-loving, or polar, and water-averse, or hydrophobic, polymers fold and bind together. They found these random sequence chains of both types of polymers can collapse and fold into specific compact conformations that expose hydrophobic surfaces, thus serving as catalysts for elongating other polymers. These particular polymer chains, referred to as "foldamer" catalysts, can work together in pairs to grow longer and develop more informational sequences.

This process, according to the authors, provides a basis to explain how random chemical processes could have resulted in protein-like precursors to biological life. It gives a testable hypothesis about early prebiotic polymers and their evolution.

"By showing how prebiotic polymers could have become informational 'foldamers', we hope to have revealed a key step to understanding just how life started to form on earth billions of years ago," explained Professor Dill.

Explore further: New theory of polymer length provides improved estimates of DNA and RNA size

More information: Elizaveta Guseva et al. Foldamer hypothesis for the growth and sequence differentiation of prebiotic polymers, Proceedings of the National Academy of Sciences (2017). DOI: 10.1073/pnas.1620179114

Related Stories

Synthetic imprinted polymers recognized by DNA

April 14, 2017

A UNT chemist is part of an international team who just made a breakthrough in DNA research. Using a polymer matrix, the team was able to imprint a sequence of a single strand DNA.

New study hints at spontaneous appearance of primordial DNA

April 7, 2015

The self-organization properties of DNA-like molecular fragments four billion years ago may have guided their own growth into repeating chemical chains long enough to act as a basis for primitive life, says a new study by ...

Researchers use light to design defined molecule chains

December 15, 2016

Chemists of Karlsruhe Institute of Technology (KIT) have succeeded in specifically controlling the setup of precision polymers by light-induced chemical reactions. The new method allows for the precise, planned arrangement ...

Model offers insight into how life continues to evolve

November 8, 2016

(Phys.org)—One of the most puzzling things about evolution is that, even after 4 billion years, it hasn't stopped. Instead of culminating in a single best adapted species, today the Earth contains an estimated 8.7 million ...

When it comes to polymer fragility, size does matter

October 18, 2016

Polymers are very large molecules consisting of thousands, even millions, of atoms bonded together in a repeating pattern similar to a chain. They make up many of the things around us we consider part of our everyday lives, ...

Recommended for you

New X-ray spectroscopy explores hydrogen-generating catalyst

November 22, 2017

Using a newly developed technique, researchers from Japan, Germany and the U.S. have identified a key step in production of hydrogen gas by a bacterial enzyme. Understanding these reactions could be important in developing ...

4 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

julianpenrod
1 / 5 (3) Aug 24, 2017
Note carefully, though, among other things, they may manage to fabricate some complex molecules under special circumstances, and they may even manage to get some of them in contact with each other, but they still have not created life. That is, they have not brought about the continuous expression, action, interaction that constitutes life. They keep working at it and working at it but life is not being produced. In fact, it looks like life is a separate essence in and of itself and something they, acting only in service to denying the presence of God, will not create.
A side point, too. Nowhere is any consideration made to degradation of the complex chemicals they make. They suggest that they came about in complicated circumstances, but nowhere do they indicate that they could have survived in those circumstances long enough to do anything.
TheMatrixDNA
1 / 5 (3) Aug 24, 2017
From Matrix/DNA perspective, we would trying to insert light ( preference for natural light ) somewhere into the computational simulation. What informations does have these initial polymers? If not about themselves and maybe, the random event producing them? When growing to foldamers, it means acquiring more atoms: which information has the foldamers if not " information about themselves plus information of atoms, which probable they already have? At this point they are still non-biological organization of matter. They are at the same level of minerals, rocks, sand... How could them to jump from here to an astonishing new complexity?
We have a model of the building block of astronomic systems and a theoretical mechanism that makes possible the information from these systems being transferred to terrestrial atoms through stellar energy, cosmic radiation, etc. It happens that the configuration of this astronomic system is exactly the configuration of a lateral base-pair of nucleotides.
torbjorn_b_g_larsson
5 / 5 (3) Aug 26, 2017
"But it has remained a mystery what actions could then prompt short chemical polymer chains to develop into much longer chains that can encode useful protein information."

That is only true for the biochemists that want to do it in chemical pools, while evolutionists and geologists have found potential solutions long since. Alkaline hydrothermal vents works as thermophoresis reactors and thermal gradients in pores as polymerization locales that makes long enough nucleotide sequences (> 200 nt) to produce self-replicating polymers (with template replication in the same hot-cold convective reactor). "The gradient accumulates monomers by thermophoresis and convection while retaining longer polymers exponentially better. ... We experimentally validate the theory ..." [ https://www.ncbi....3657786/ ]
torbjorn_b_g_larsson
5 / 5 (4) Aug 26, 2017
@julianpenrod: The work and its results speak for themselves, and it passed peer review. Your only point seem to be to claim irrelevant criteria and discuss irrelevant religion. And the only reason I respond is in case some other reader does not understand your inept commentary for the trolling it is.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.