Reaction catalyzed by protein geranylgeranyltransferase type I (2.5.1.59)
+
=
+
geranylgeranyl diphosphate
+
(biotin-CONH-(CH2)5-CO-)-GTPRASNRSCAIS
=
diphosphate
+
(biotin-CONH-(CH2)5-CO-)-GTPRASNRS-S-geranylgeranyl-CAIS