Microheterogeneity of globulin-1 storage protein from French bean with isoelectrofocusing.

The major storage protein fraction, globulin-1 protein, of French bean (Phaseolus vulgaris L.) was analyzed by two-dimensional electrophoresis. The protein pattern suggested a more complex system for globulin-1 protein than the model of three polypeptides, alpha, beta, and gamma, differing in molecular weight. Isoelectrofocusing analyses of the individual proteins showed that each exhibited charge microheterogeneity over a similar pH range. Isoelectrofocusing banding patterns may help to understand the relationships between the globulin-1 polypeptide subunits.