Reaction catalyzed by endoplasmic reticulum Man9GlcNAc2 1,2-alpha-mannosidase (3.2.1.209)

		+	3	H2O	=			+	3
	alpha-D-mannopyranosyl-(1,2)-alpha-D-mannopyranosyl-(1,2)-alpha-D-mannopyranosyl-(1,3)-[alpha-D-mannopyranosyl-(1,2)-alpha-D-mannopyranosyl-(1,3)-[alpha-D-mannopyranosyl-(1,2)-alpha-D-mannopyranosyl-(1,6)]-alpha-D-mannopyranosyl-(1,6)]-beta-D-mannopyranosyl-(1,4)-2-(acetylamino)-2-deoxy-beta-D-glucopyranosyl-(1,4)-2-(acetylamino)-2-deoxy-beta-D-glucopyranose	+		3 H2O	=		alpha-D-mannopyranosyl-(1,2)-alpha-D-mannopyranosyl-(1,3)-[alpha-D-mannopyranosyl-(1,3)-[alpha-D-mannopyranosyl-(1,6)]-alpha-D-mannopyranosyl-(1,6)]-beta-D-mannopyranosyl-(1,4)-2-(acetylamino)-2-deoxy-beta-D-glucopyranosyl-(1,4)-2-(acetylamino)-2-deoxy-beta-D-glucopyranose	+		3 D-mannose