The primary structure of the parvalbumin II of pike (Esox lucius)

The amino acid sequence of the parvalbumin II of the pike is reported. The protein has a molecular weight of 11 435. It consists of a single polypeptide chain of 107 amino acid residues with an acetyl group blocking the N-terminus and an alanine residue at the C-terminus. The molecule has been enzymically cleaved by trypsin, thermolysin and by the protease of the Staphylococcus aureus strain V8. Chemical cleavages make use of the CNBr reaction and of the sulfocyanoethylation method. The comparison of this amino acid sequence with that of the parvalbumin III of the pike indicates that these two homologous proteins belong respectively to two different subgroups derived from an early gene duplication of an ancestral gene at least prior to the differentiation of the Osteichthyes.