RESUMO
A statistical analysis aimed at obtaining some informations on a possible correlation between simultaneous amino acid substitutions is proposed. This method is applied to a set of cytochrome C, at the level of tandem and triple substitutions separated along the peptide chain by 1 to 15 peptide bonds. Monte-Carlo simulations are performed and the results are compared. We find a significant occurrence of three adjacent amino acid substitutions in which the first replacement requires a two nucleotide substitution. A possible explanation of this fact is proposed on the basis of covarions.
Assuntos
Grupo dos Citocromos c/biossíntese , Modelos Biológicos , Sequência de Aminoácidos , Animais , Evolução Biológica , Código Genético , PlantasRESUMO
Utilising the homology between goose alpha chain hemoglobin and chicken, the primary arrangement of the amino acid residues of the alpha chain (major component) of goose hemoglobin is presented. Data were obtained from amino acid analysis of the isolated alpha chain and of tryptic peptides of the chain. Their chemical structure was established by Edman degradation, carboxypeptidase A and B and leucineaminopeptidase digestion.