Studies on boar seminal plasma proteins. 3. Fractionation by gel filtration, ion exchange and other means.

Abstract

1. Sephadex G-200 separates the proteins of boar seminal plasma into 2 major components. 2. The larger (80–90% of the total) has a sedimentation constant of 2.3 S and represents protein which is heat coagulable. It corresponds broadly with the proteins which are soluble at low ionic strength (I 0.015; pH 8). 3. The smaller (10–20% of the total) has a sedimentation constant of between 7 and about 40 S and represents protein which is not precipitated by 12% Na2SO4 or by low ionic strenght. It does, however, precipitate at low ionic strength on addition of an aliquot of the 2.3-S material from Sephadex G-200. 4. The precipitate at low ionic strength produced by a mixture of 7 S with an aliquot of the 2.3-S proteins changes slowly and irreversibly into a form, the soluble fraction of which has a sedimentation constant of 5 S. 5. The copious precipitate which appears on cooling samples of seminal plasma from some boars is also a 7-S protein.