Physical heterogeneity of bovine γ-globulins: Characterization of γM and γG globulins

The γG globulins of bovine serum were characterized by anion exchange chromatography, immunoelectrophoresis, zone electrophoresis, ultracentrifugation, and analysis of the products of papain digestion. Their properties were similar to those of analogous components of human serum. Fast and slow γG globulins were distinguished on the basis of differences in electrophoretic migration rates, chromatographic elution positions, and biological activities (complement fixation). Antigenic differences were detectable only in immunoelectrophoretic patterns (spur formation). Bovine γM was found to have properties quite similar to those of the analogous protein in human serum as determined by the methods of gel filtration, immunoelectrophoresis, anion exchange chromatography, ultracentrifugation, and reduction with mercaptoethanol. Bovine γA was provisionally recognized in immunoelectrophoretic analyses of serum and chromatographic fractions.