title: Biochemical and immunological comparisons between the human and boar proacrosin-acrosin proteinase systems.
abstract: Biochemical and immunochemical methods have been used to examine the proacrosin-acrosin system of human and boar spermatozoa. Marked biochemical similarities including the relative molecular weights of proacrosin (approx. 55,000), alpha-acrosin (45,000-49,000) and beta-acrosin (34,000-38,000) were observed for both species. In addition, the time course of proacrosin autoconversion between 0 to 60 min revealed that the purified proacrosin from both species autoconverted to alpha-acrosin and then to beta-acrosin at approximately the same time intervals. Despite these apparent biochemical similarities, distinct immunological differences between the human and boar proacrosin-acrosin systems were observed. The human proacrosin antibody immunoreacted with purified human proacrosin and alpha-acrosin but not with beta-acrosin. The antibodies to boar proacrosin cross-reacted with the purified boar proacrosin, alpha-acrosin and beta-acrosin. The antibodies to human proacrosin also cross-reacted with boar proacrosin and to a weak extent with boar alpha-acrosin but not with the boar beta-acrosin. While antibodies to boar proacrosin did not react with any of the components of the human proacrosin system. Additionally, in the non-purified sperm extracts the human proacrosin antibody preparation reacted with several proteins larger than proacrosin and one with a molecular weight of approximately 34,000. In the non-purified boar sperm extracts, the antibodies to boar proacrosin only cross-reacted with the known components of the proacrosin-acrosin system suggesting a high degree of specificity. Thus, immunochemical evidence is presented that indicates there are specific structural differences which occur in the proacrosin-acrosin system of mammalian sperm.
mesh_terms: D000176:Acrosin / Q000096:biosynthesis* / Q000276:immunology; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D004591:Electrophoresis, Polyacrylamide Gel; D004792:Enzyme Precursors / Q000096:biosynthesis* / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D008297:Male; D012697:Serine Endopeptidases / Q000096:biosynthesis*; D013094:Spermatozoa / Q000201:enzymology* / Q000378:metabolism; D013552:Swine
chemical_list: D000911:Antibodies, Monoclonal; D004792:Enzyme Precursors; D012697:Serine Endopeptidases; C022438:proacrosin; D000176:Acrosin