Molecular forms of bovine gamma-glutamyltransferase and their enzyme immunoassay

Light form of bovine kidney gamma-glutamyl transferase was isolated from heavy form of the enzyme after digestion with bromelain. Its apparent molecular weight was 95,000 and in SDS solution it dissociated into two non-identical subunits with molecular weights 26,000 and 69,000. No substantial differences between both forms in activation, kinetic parameters and inhibition with anthglutin and its isomers were noted. Using enzyme immunoassay it was possible to determine one enzyme form in the presence of the other. This was applied for studies of gamma-glutamyltransferase forms in cow serum and colostrum.