Reaction catalyzed by mannosylglycoprotein endo-beta-mannosidase (3.2.1.152)

		+		H2O	=			+
	Manbeta(1-4)GlcNAcbeta(1-4)GlcNAc-pyridylaminoside	+		H2O	=		beta-D-mannose	+		GlcNAcbeta(1-4)GlcNAc-pyridylaminoside