Some properties of mitogenic components isolated from phytohemagglutinin by a preparative gel electrophoresis

Abstract Mitogenic components have been isolated from a commercially available phytohemagglutinin by a preparative gel electrophoresis. Characterization was accomplished by analytical disc electrophoresis, amino acid and carbohydrate analyses, NH 2 -terminal amino acid determination, analytical ultracentrifugation, and optical rotatory dispersion. Two mitogenic glycoprotein fractions were isolated electrophoretically, both having a molecular weight of about 140,000 but differing slightly in chemical composition. Differences also were noted in optical absorption and optical rotatory dispersion, suggesting a difference in electrophoretic mobility probably affected by charge, shape and conformation. These homogeneous glycoproteins showed mitogenic activity 50-fold greater than that of a commercial phytohemagglutinin (Difco PHA-P). Moreover, they had practically no hemagglutinating and leukoagglutinating activities.