Purification and partial peptide sequence analysis of the boar 32 kDa sperminogen

Boar 32 kDa sperminogen was purified from acid extracts of washed epididyma l spermatozoa, and partial peptide sequence was determined. Boar sperminoge n was purified from the acid extracts of boar spermatozoa by gel filtration through Sephadex G-75 column, followed by preparative SDS-PAGE. Gelatin zy mographic analysis of the gel-filtered fractions showed that sperminogen wa s composed of three separate proteolytic bands. Among the three proteolytic bands, the 32 kDa sperminogen band which showed the strongest proteolytic activities upon activation was sliced out and eluted from the gel fragments . The eluted 32 kDa sperminogen was then subjected to peptide sequencing. S ince the N-terminus of the 32 kDa sperminogen was blocked for peptide seque ncing by Edman degradation method, the internal amino acid sequence of the sperminogen was obtained from the CNBr-digested peptides of sperminogen. Th e amino acid sequence of the analyzed peptide of the 32 kDa sperminogen sho wed 100% identity with that of proacrosin.