Spectroscopy of the genetic code

Discussions of the nature of the genetic code cannot be divorced from the biological context of its origin and evolution. We briefly review some of the main arguments that have been put forward for the evolution of the genetic code, together with the salient biological background. Longstanding observations of genetic code regularities have led to combinatorially-based assertions about its structure. However, it is also possible to extend such `symmetry' descriptions to continuous symmetries or supersymmetries, especially in relation to the pattern of redundancy (degeneracy) of the genetic code. We give an account of some recent work along these lines. This is supported by graphical presentations, and some data fits, of samples of measured physico-chemical properties of codons and amino acids across the genetic code table. Finally, we review codon-anticodon recognition in terms of conformational degrees of freedom, and structural/stereochemical and kinetic considerations. Based on this, we suggest a possible role for quantum processes at important stages of codon reading and translation