The structure of caltrin, the calcium-transport inhibitor of bovine seminal plasma.

Abstract

The amino acid sequence of the bovine seminal protein, caltrin, which inhibits calcium transport into spermatozoa, has been determined. The protein contains 47 amino acid residues. Parts of the sequence are identical with that reported for bovine seminal plasmin, a protein possessing antibacterial activity. We believe the proteins are identical and that the previously reported sequence of seminal plasmin is in error.