Carnivora: the primary structure of the common otter (Lutra lutra, Mustelidae) hemoglobin.

The hemoglobin of the Common Otter (Lutra lutra, Carnivora) contains only one component. The complete primary structures of the alpha- and beta-chains are presented. They were separated by high-performance liquid chromatography and the sequences determined by automatic liquid and gas-phase Edman degradation of the chains and their tryptic peptides. The alpha-chains show 18 and the beta-chains 13 substitutions compared to human alpha- and beta-chains, respectively. In the alpha-chains one heme- and two alpha 1/beta 1-contacts are exchanged. In the beta-chains the replacements involve one heme-, one alpha 1/beta 1-, and one alpha 1/beta 2-contact. The alpha- and beta-chains of the Common Otter are compared to those of other Carnivora hemoglobins. The unexpected low number of substitutions between Common Otter hemoglobin and that of Lesser Panda as well as of Harbor Seal is discussed.