Reaction catalyzed by protein geranylgeranyltransferase type I (2.5.1.59)
+
=
+
geranylgeranyl diphosphate
+
Ras-Cys-Val-Leu-Leu
=
diphosphate
+
Ras-S-geranylgeranyl-Cys-Val-Leu-Leu