The different molecular weight forms of bovine liver rhodanese

Sedimentation equilibrium studies show that there are two forms of bovine liver rhodanese in crystalline enzyme preparations of full specific activity. One form dissociates to a species with a limiting molecular weight close to 19,000. The second form is nondissociable under the same experimental conditions. It exhibits a molecular weight of approximately 33,000. These conclusions are augmented by data from polyacrylamide gel electrophoresis and molecular exclusion chromatography. They serve to explain apparent inconsistencies in previous reports on this enzyme.