Reaction catalyzed by anaerobic magnesium-protoporphyrin IX monomethyl ester cyclase (1.21.98.3)
+
=
+
+
131-oxo-magnesium-protoporphyrin IX 13-monomethyl ester
+
S-adenosyl-L-methionine
=
3,8-divinyl protochlorophyllide a
+
5'-deoxyadenosine
+
L-methionine
