Methemalbumin: reality and myth.
The ability to form methemalbumin by binding oxidized heme is described frequently as a characteristic of albumin from all animal species. Actually, only albumin from a limited number of species makes methemalbumin. Lack of recognition of interspecies differences has led to the myth of methemalbumin in domestic animals. The literature on methemalbumin is reviewed including the chemical characteristics of true methemalbumin and the misuse of mythical methemalbumin.