| Product Name |
anaerobic magnesium-protoporphyrin IX monomethyl ester cyclase |
| Example Structure |
 |
| Synonyms |
BChE, chlE, Cyan7425_4778, Cyan7822_3999, F_1025, MPE cyclase, oxygen-independent Mg-protoporphyrin IX monomethyl ester cyclase |
| EC Number |
1.21.98.3 |
| CAS Registry Number |
|
| Comments |
This radical AdoMet enzyme participates in the biosynthesis of chlorophyllide a in anaerobic bacteria, catalysing the formation of an isocyclic ring. Contains a [4Fe-4S] cluster and a cobalamin cofactor. The same transformation is achieved in aerobic organisms by the oxygen-dependent EC 1.14.13.81, magnesium-protoporphyrin IX monomethyl ester (oxidative) cyclase. Some facultative phototrophic bacteria, such as Rubrivivax gelatinosus, possess both enzymes. |
| Cofactor |
iron-sulfur;adenosylcob(III)alamin |
| History |
|
| Reactions |
Magnesium-protoporphyrin Ix 13-monomethyl ester + 3 S-adenosyl-L- methionine + H(2)O = 3,8-divinyl protochlorophyllide a + 3 5′-deoxyadenosine + 3 L-methionine. |
