Reaction catalyzed by (N-acetylneuraminyl)-galactosylglucosylceramide N-acetylgalactosaminyltransferase (2.4.1.92)

		+			=			+
	UDP-N-acetyl-alpha-D-galactosamine	+		ganglioside N-acetyl-lyso-GM3	=		UDP	+		ganglioside N-acetyl-lyso-GM2