GM2 ganglioside activator occurs in multiple forms.

The protein which activates the hydrolysis of GM2 ganglioside by hexosaminidase A was purified from human kidney. The GM2 activator had a molecular mass of 28 kDa by gel filtration and was resolved into three major bands using polyacrylamide gel electrophoresis in the presence of SDS with molecular masses of 23, 22 and 21 kDa. These three bands corresponded respectively to strongly binding, weakly binding and non-binding fractions of GM2 activator chromatographed through concanavalin A-Sepharose, indicating that GM2 activator exists in multiple glycosylated forms.