Aggregated forms of heparin-binding and non-heparin-binding proteins of boar seminal plasma and their binding properties

Boar seminal plasma proteins were separated by affinity chromatography on i mmobilized heparin into two portions: heparin-binding (H) and non-heparin-b inding (H-) proteins. Gel chromatography of the H+ portion yielded four mai n protein fractions of >150, 45, 30 and 20 kDa, while that of the Ii portio n resulted in the separation into three main protein fractions of >150, 30 and 20 kDa, HPLC analysis and N-terminal sequencing used to characterize th e composition of the protein fractions obtained by gel chromatography revea led that all consisted of low (12-16 kDa) molecular weight components: the H+ fraction consisted of DQH sperm protein, AQN and AWN spermadhesins where as the H- fraction consisted of PSPI and PSPII spermadhesins. The high mole cular weight values of fractions obtained by gel chromatography thus sugges t that the proteins are present in boar seminal plasma in the form of aggre gates. Interactions of individual boar seminal plasma proteins and their ag gregates present in the H+ and H- fractions with acid polysaccharides were estimated.