Separation and partial characterization of two galactosyltransferase isoforms from malignant ascitic fluid

Galactosyltransferase was isolated from human malignant ascites by ammonium sulphate precipitation, alpha-lactalbumin affinity chromatography and by the removal of contaminating immunoglobulins with protein A chromatography. Two isoforms of galactosyltransferase were separated by DEAE chromatography, and partially characterised by gel filtration, non-denaturing polyacrylamide gel electrophoresis, concanavalin A binding and enzyme kinetics. The two forms isolated were compared with the isoenzymes previously described and the biochemical basis for the difference between the two forms discussed.