Лед и происхождение жизни
Sep. 27th, 2010 04:24 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
imbgВ последнем номере Nature Communication представлена интересная гипотеза - о возможной роли льда в опосредовании РНК-репликации с помощью рибозимов - специфических РНК с ферментативной (в данном случае - полимеразной) активностью. Эта открытие поможет объяснить один из важнейших вопросов биологии - вопрос о том, как же зародилась жизнь на Земле.
Английский абстракт статьи:
Ice as a protocellular medium for RNA replication
James Attwater, Aniela Wochner, Vitor B. Pinheiro, Alan Coulson & Philipp Holliger
Nature Communications 1 , Article number: 76 doi:10.1038/ncomms1076
Received 20 May 2010 Accepted 23 August 2010 Published 21 September 2010
A crucial transition in the origin of life was the emergence of an informational polymer capable of self-replication and its compartmentalization within protocellular structures. We show that the physicochemical properties of ice, a simple medium widespread on a temperate early Earth, could have mediated this transition prior to the advent of membraneous protocells. Ice not only promotes the activity of an RNA polymerase ribozyme but also protects it from hydrolytic degradation, enabling the synthesis of exceptionally long replication products. Ice furthermore relieves the dependence of RNA replication on prebiotically implausible substrate concentrations, while providing quasicellular compartmentalization within the intricate microstructure of the eutectic phase. Eutectic ice phases had previously been shown to promote the de novo synthesis of nucleotide precursors, as well as the condensation of activated nucleotides into random RNA oligomers. Our results support a wider role for ice as a predisposed environment, promoting all the steps from prebiotic synthesis to the emergence of RNA self-replication and precellular Darwinian evolution.
link
Английский абстракт статьи:
Ice as a protocellular medium for RNA replication
James Attwater, Aniela Wochner, Vitor B. Pinheiro, Alan Coulson & Philipp Holliger
Nature Communications 1 , Article number: 76 doi:10.1038/ncomms1076
Received 20 May 2010 Accepted 23 August 2010 Published 21 September 2010
A crucial transition in the origin of life was the emergence of an informational polymer capable of self-replication and its compartmentalization within protocellular structures. We show that the physicochemical properties of ice, a simple medium widespread on a temperate early Earth, could have mediated this transition prior to the advent of membraneous protocells. Ice not only promotes the activity of an RNA polymerase ribozyme but also protects it from hydrolytic degradation, enabling the synthesis of exceptionally long replication products. Ice furthermore relieves the dependence of RNA replication on prebiotically implausible substrate concentrations, while providing quasicellular compartmentalization within the intricate microstructure of the eutectic phase. Eutectic ice phases had previously been shown to promote the de novo synthesis of nucleotide precursors, as well as the condensation of activated nucleotides into random RNA oligomers. Our results support a wider role for ice as a predisposed environment, promoting all the steps from prebiotic synthesis to the emergence of RNA self-replication and precellular Darwinian evolution.
link
