Reaction catalyzed by xylan alpha-1,2-glucuronosidase (3.2.1.131)

		+		H2O	=			+
	aldotetraouronic acid	+		H2O	=		4-O-methyl-D-glucuronic acid	+		Xylbeta(1-4)Xylbeta(1-4)Xylbeta(1-4)Xyl