Hemisphaericin-D,a dialysable and polymerizable protease found in Bromelia hemisphaerica

Summary Proteolytic activity was detected outside dialysis bag filled with Bromelia hemisphaerica fruit juice. The dialysable protease was concentrated and purified from small molecular weight contaminants on Sephadex G-10 columns. Acrylamide gel electrophoresis of the dialysable protease, in the presence of SDS and 2-mercaptoethanol. demonstrated a single protein band of about 8000 daltons mol. wt. The same single band with identical mobility was shown with hemisphaericin, the enzyme retained inside the dialysis bag. The small protease, named Hemisphaericin-D was antigenic in rabbits and the antibodies cross-reacted fully with Hemisphaericin. Hemisphaericin-D appears not to be a degradation product of Hemisphaericin.This is contribution No. 22 from Departamento de Biología Experimental, Facultad de Medicina, UNAM, Mexico.Acknowledgments. We thank Irma Coria and Silvia Vizconde for skillful assistance. Interchange of information with Dr E. Toro-Goyco, University of Puerto Rico, School of Medicin, was most helpful.