Immunological Identification of Seminalplasmin in Tissue Extracts of Sex Glands of Bull

Abstract

Using immunoglobulin G (IgG)- antibodies raised against highly purified, homogenous seminalplasmin (SPLN), an antimicrobial protein of bovine seminal plasma, it has been shown that bovine ampullae, gland vesicularis and corpus prostate, but not testes and epididymis, contain SPLN. The content as estimated by radioimmunoassay employing [125I]SPLN was: ampullae. 267±13: gland vesicularis, 275±14 and corpus prostate, 445 ±22 μg per gram wet weight of the tissue. SPLN, as characterised by high performance liquid chromatography and in vivo inhibition of RNA synthesis in E. coli, was isolated from gland vesicularis. The SPLN content of bovine seminal plasma was shown to be 1%. A chymotryptic peptide of SPLN comprising residues 1-13 from the amino terminus was found to compete with [125I]SPLN for binding to anti-SPLN IgG.