Parvalbumin from rabbit muscle. Isolation and primary structure.

A parvalbumin, with its characteristic low molecular weight (approximately 12000) acidic isoelectric point (approximately 5.5), ultraviolet spectrum (maxm 259 nm) and Ca2+-binding capacity (2 mol/mol protein) has been isolated from rabbit (Oryctolagus cuniculus) muscle. Its primary structure has been determined from a study of its tryptic peptides and of overlapping peptides generated by limited tryptic digestion and by chymotryptic and thermolytic digestions of the protein. The amino acid sequence so obtained is considered in comparison with those known for other parvalbumin and for rabbit troponin C.