Purification and partial peptide sequence analysis of the boar proacrosin binding protein

Boar proacrosin binding protein has been purified and the partial peptide sequence of the CNBr-digested proacrosin binding protein has been determined. Proacrosin binding protein was purified as a proacrosin and proacrosin binding protein complex from the acid extracts of boar spermatozoa through gel filtration. After the proacrosin binding protein was dissociated from proacrosin by freeze-thaw method, the proacrosin binding protein was purified through gel filtration. Fractions containing the proacrosin binding protein were pooled and were concentrated by lyophilization and then subjected to CNBr digestion. Four major CNBr-digested peptides were subjected to N-terminal peptide sequencing. All four showed the same N-terminus sequence.