The complete amino acid sequence of the major component myoglobin from the arctic minke whale, Balaenoptera acutorostrata.

The complete primary structure of the major component myoglobin from the Arctic minke whale, Balaenoptera acutorostrata, was determined by specific cleavage of the protein to obtain large peptides which are readily degraded by the automatic sequencer. Over 80% of the amino acid sequence was established from the three peptides resulting from the cleavage of the apomyoglobin at the two methionine residues with cyanogen bromide along with the four peptides resulting from the cleavage of the methylacetimidated apomyoglobin at the three arginine residues with trypsin. The further digestion of the central cyanogen bromide peptide with trypsin and S. aureus strain V8 protease enabled the determining of the remainder of the covalent structure. This myoglobin differs from that of the dwarf sperm whale, Kogia simus, at 16 positions, and the common dolphin, Delphinus delphis, at 14 positions, from that of the common porpoise, Phocaena phocaena, and the bottlenosed dolphin, Tursiops truncatus at 13 positions, from that of the Amazon River dolphin, Inia geoffrensis, at 10 positions, and from that of California gray whale, Eschrichtius gibbosus, at 3 positions- All of the substitutions observed in this sequence fit easily into the three-dimensional structure of the sperm whale myoglobin.