Reaction catalyzed by complement subcomponent C1s (3.4.21.42)

		+		H2O	=			+
	C2H5CO-Lys-(epsilon-Cbz)-Gly-Arg-4-nitroanilide	+		H2O	=		C2H5CO-Lys-(epsilon-Cbz)-Gly-Arg	+		4-nitroaniline