Experimental verification of acquisition of hemoprotein high-order functions by reverse molecular evolution

点击翻译按钮获取中文摘要

On the basis of the sequence database for proteins now available, we constructed phylogenetic trees for myoglobin and inferred the amino acid sequences for two ancestor animal's myoglobins, one for mammalian and the other for fishes (reverse evolution). These ancestral myoglobins, synthesized in E. coli, showed high oxygen affinity, stable structure and lowered autooxidation rate compared to the corresponding extant neighbor animals, North American opossum and Zebra fish. Thus, it is considered that, in mammals and fishes, myoglobin has evolved so that oxygen binding function is adapted to environments at the sacrifice of structural stability and autooxidation.