Lipid-Assisted Polymerization of Nucleotides

Abstract

In addition to being one of the proponents of the “Lipid World hypothesis”, David Deamer, together with other colleagues, pioneered studies involving formation of RNA-like oligomers from their ‘non-activated’, prebiotically plausible monomeric moieties. In particular, the pioneering work in this regard was a publication from 2008 in Origins of Life and Evolution of Biospheres, The Journal of the International Astrobiology Society, wherein we described the formation of RNA-like oligomers from nucleoside 5’-monophosphates. In that study, we had simulated a terrestrial geothermal environment, a niche that is thought to have facilitated the prebiotic non-enzymatic synthesis of polynucleotides. We showed that a mixture of lipids and non-activated mononucleotides resulted in the formation of relatively long strands of RNA-like polymers when subjected to repeated cycles of dehydration and rehydration (DH-RH). Since 2008, terrestrial geothermal niches and DH-RH conditions have been explored in the context of several other prebiotic processes. In this article, we review the work that we and other researchers have carried out since then in this line of research, including the development of new apparatus to carry out the simulation of prebiotic terrestrial geothermal environments.

The Coevolution of Biomolecules and Prebiotic Information Systems in the Origin of Life: A Visualization Model for Assembling the First Gene

“…Similar to nucleotides, codons could be linked to one another in a chain by a condensation reaction to form oligonucleotides and pre-mRNA-like molecules. Olasagasti and Rajamani [ 57 ] showed the polymerization of RNA-like molecules experimentally from non-activated prebiotic mononucleotides and oligonucleotides via condensation reactions. These authors simulated a terrestrial hydrothermal environment that fluctuates between wet and dry cycling during seasonal change.…”

Membrane Catalysed Formation of Nucleotide Clusters and Its Role in the Origins of Life

“…An ongoing investigation in the molecular OoL research has been the understanding of the formation and synthesis of the first polymers of nucleic acids [21][22][23] . The comprehension of how RNA-like molecules were produced and its emergence in the absence of the catalysts and metabolism is elementary but rapidly evolving [24][25][26][27][28][29][30][31][32][33] .…”

“…Not only could the lipids safely encapsulate the nucleotides, it is likely to facilitate their polymerization as well. Nearly a decade ago, the concept of guided polymerisation was introduced [36][37][38] , and it was later discovered that RNA-like polymers could be synthesised nonenzymatically 39,40 in different settings reproducing prebiotic cycles such as fluctuations in hydration 26,34,[41][42][43] and the presence of various organising matrix [26][27][28][29][30][31]44 . Nucleotides in solution are highly diffusive, but diverse substrates provide different type of confinement environments.…”

Membrane Catalysed Formation of Nucleotide Clusters and Its Role in the Origins of Life

“…An ongoing investigation for researchers studying the molecular OoL [15][16][17] research has been the understanding of the formation and synthesis of the first polymers of nucleic acids. The comprehension of how RNA-like molecules were produced and its emergence in the absence of the catalysts and metabolism is elementary but rapidly evolving [18][19][20][21][22][23][24][25][26][27] .…”

“…The nonenzymatic polymerisation of RNA, a condensation reaction where phosphodiester bonds are formed, is thought to be a crucial step in origin of simple life forms in the prebiotic time 32 . Nearly a decade ago, the concept of guided polymerisation was introduced [33][34][35] , and it was later discovered that RNA-like polymers could be synthesised non-enzymatically 36,37 in different settings reproducing prebiotic cycles such as fluctuations in hydration 20,28,[38][39][40] and the presence of various organising matrix [20][21][22][23][24][25]41 ; conditions which procreate prebiotic environment. Nucleotides in solution are highly diffusive, but diverse substrates provide different type of confinement environments, such as phospholipid bilayers (membranes) allow 2D confinement 20,25,26 , salt confines them in between salt crystallites 24 , or nucleotides can confine in the layered structure of clay 21,22,[42][43][44] .…”