Astrobiology: Life in the Universe Forming a Definition for Life. Boron Enrichment in Martian Clay. We have detected a concentration of boron in martian clay far in excess of that in any previously reported extra-terrestrial object. This enrichment indicates that the chemistry necessary for the formation of ribose, a key component of RNA, could have existed on Mars since the formation of early clay deposits, contemporary to the emergence of life on Earth. Given the greater similarity of Earth and Mars early in their geological history, and the extensive disruption of Earth's earliest mineralogy by plate tectonics, we suggest that the conditions for prebiotic ribose synthesis may be better understood by further Mars exploration.
Figures Citation: Stephenson JD, Hallis LJ, Nagashima K, Freeland SJ (2013) Boron Enrichment in Martian Clay. Editor: Stefan Maas, NIGMS, NIH, United States of America Received: March 12, 2013; Accepted: April 16, 2013; Published: June 6, 2013 Copyright: © 2013 Stephenson et al. Competing interests: The authors have declared that no competing interests exist.
Astrobiology: Life in the Universe. Astrobiology: Life in the Universe. Yin and Yang: Polypeptide and Polynucleotide December 20, 2012 / Written by: Loren Williams Two biopolymers have come to dominate the enzymatic and encoding machinery of contemporary life: polypeptides and polynucleotides. These molecules both exhibit exquisitely well-adapted self-assembly characteristics, albeit employing orthogonal self-assembly strategies. In contemporary life, the ribosome enables the flow of information between these two divergent, yet correlated biopolymers. This review discusses the relationship between these two biopolymers, with a focus on the early evolution of the ribosome. Charles Darwin famously observed [1] that “…from so simple a beginning, endless forms most beautiful and most wonderful have been, and are being, evolved”.
Figure 1. Progress in Studies on the RNA World. SAO/NASA ADS Astronomy Abstract Service · Electronic Refereed Journal Article (HTML)· References in the article· Citations to the Article (1) (Citation History) · Refereed Citations to the Article· Reads History· · Translate This Page Abstract The montmorillonite-catalyzed reactions of D, L-ImpA with D, L-ImpU generates RNA-like oligomers. The structures of the dimers to pentamers were investigated and homochiral products were identified in greater amounts than would be expected if theoretical amounts of each were formed.
The homochirality increased from 64% to 97% as the chain length increased from dimers to pentamers.