Abstract:
Fifty-one sequences of the
hetR gene from
Nostoc and related species of cyanobacteria were studied. The coding proteins of
hetR were analyzed by bioinformatics and phylogenetic analysis. The adaptive evolutionary characteristics of
hetR were studied using the branch, site, and branch-site models. Phylogenetic analysis showed that the inner group could be divided into four large branches. Based on the adaptive evolutionary analysis, no significant positive selection sites were detected in other branches and algae strains of the three evolutionary models, indicating that most of the sites were under negative selection pressure. However, significant positively selected sites (126T) were detected in
Nostoc commune (CHAB2802), indicating that the
hetR gene has undergone adaptive evolution in
Nostoc.