Coding coenzyme handles: a hypothesis for the origin of the genetic code.

E Szathmáry

doi:10.1073/pnas.90.21.9916

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Coding coenzyme handles: a hypothesis for the origin of the genetic code.

E Szathmáry

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Abstract

The coding coenzyme handle hypothesis suggests that useful coding preceded translation. Early adapters, the ancestors of present-day anticodons, were charged with amino acids acting as coenzymes of ribozymes in a metabolically complex RNA world. The ancestral aminoacyl-adapter synthetases could have been similar to present-day self-splicing tRNA introns. A codon-anticodon-discriminator base complex embedded in these synthetases could have played an important role in amino acid recognition. Extension of the genetic code proceeded through the take-over of nonsense codons by novel amino acids, related to already coded ones either through precursor-product relationship or physicochemical similarity. The hypothesis is open for experimental tests.

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Amino Acyl-tRNA Synthetases Biological Evolution Coenzymes Genetic Code Introns Models, Genetic RNA, Catalytic RNA, Transfer Journal Article Research Support, Non-U.S. Gov't

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E Szathmáry. 1993-11-01. Coding coenzyme handles: a hypothesis for the origin of the genetic code.. https://doi.org/10.1073/pnas.90.21.9916

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