Reaction catalyzed by protein geranylgeranyltransferase type I (2.5.1.59)

		+		S-geranylgeranyl-Ki-Ras4B	=			+		S-geranylgeranyl-Ki-Ras4B
	geranylgeranyl diphosphate	+		S-geranylgeranyl-Ki-Ras4B	=		diphosphate	+		S-geranylgeranyl-Ki-Ras4B