Homodimer and heterodimer subunits of human prostate acid phosphatase.

摘要: Human prostatic acid phosphatase (PAP) isoenzymes, designated PAP-A and PAP-B, were isolated from human seminal plasma by sequential affinity chromatography on concanavalin A L(+)-tartrate, a classic inhibitor of PAP. Both the major minor PAP-B isoenzymes exhibited similar molecular mass (100 105 kDa respectively), multiple pI values (5.05-5.35 5.05-5.12), substrate specificity. Immunological characterization revealed that possesses distinct antigenic determinants, in addition to common sites shared with PAP-A. SDS/PAGE indicated both are composed two subunits 50 each. At high salt concentration, dissociated completely into single kDa, whereas remained intact at 100 kDa. was resolved reverse-phase h.p.l.c. three components, alpha, beta gamma, each molar ratio approx. 2:1:1. contained component The alpha possessed identical amino compositions N-terminal sequences, which different those gamma components. These results indicate PAP contains isoforms, 2, gamma. PAP-A, isoenzyme, is homodimer consisting (alpha 2), mixture heterodimers, non-identical gamma).