Two types of amino acid substitutions in protein evolution.

摘要: The frequency of amino acid substitutions, relative to the expected by chance, decreases linearly with increase in physico-chemical differences between pairs involved a substitution. This correlation does not apply abnormal human hemoglobins. Since hemoglobins mostly reflect process mutation rather than selection, manifest during protein evolution substitution and difference acids can be attributed natural selection. Outside ‘abnormal’ proteins, also certain regions proteins characterized rapid rates In these cases again, except for largest pairs, frequencies seem independent parameters. limination substituents involving physicochemical once more For smaller differences, if it is operating polypeptide regions, must based on parameters other those examined.