CORRELATION BETWEEN BASE COMPOSITION OF DEOXYRIBONUCLEIC ACID AND AMINO ACID COMPOSITION OF PROTEIN

Abstract

Amino acid composition of the bulk protein isolation from 11 bacterial species whose DNA base compositions vary from 35 to 72% in guaninecytosine content has been examined. The following points are of interest: (1) The amino acid composition of the total protein is remarkably invariant to environmental changes. (2) Individual amino acids appear in distinguishably different molar proportions with rather uniform values. (3) Several significant correlations between DNA base composition and amino acid composition of protein exist. Among 18 amino acids tested, alanine, arginine, glycine, and proline are positively correlated with guanine-cytosine content of DNA. Isoleucine, lysine, aspartic acid plus asparagine, glutamic acid plus glutamine, tyrosine, and phenylalanine are negatively correlated. Histidine, valine, leucine, threonine, serine, and possibly methionine are extremely uniform with no detectable evidence of correlation. Results obtained are discussed in relation to the coding problem.