Studies on polynucleotides, XLIX. Stimulation of the binding of aminoacyl-sRNA's to ribosomes by ribotrinucleotides and a survey of codon assignments for 20 amino acids.

Abstract
All of the possible trinucleotides have been tested extensively for their ability to stimulate the binding of labeled aminoacyl-sRNA''s to ribosomes. While a large number of trinucleotides stimulated the binding of only one amino-acyl-sRNA to ribosomes significantly, many cases of ambiguous as well as weak stimulation of the binding of aminoacyl-sRNA''s were encountered. In addition, five trinucleotides, concluded from other methods to be authentic codons, failed to stimulate the binding of the appropriate aminoacyl-sRNA. By a combination of the results of the binding technique and of the results obtained by other methods, a total of 56 codon assignments have been made.