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EC 6.6.1.2 Details
show Brenda entryEC number
6.6.1.2
Accepted name
cobaltochelatase
Reaction
ATP + hydrogenobyrinate a,c-diamide + Co2+ + H2O = ADP + phosphate + cob(II)yrinate a,c-diamide + H+
Other name(s)
hydrogenobyrinic acid a,c-diamide cobaltochelatase,
CobNST,
CobNCobST,
hydrogenobyrinic-acid-a,c-diamide:cobalt cobalt-ligase (ADP-forming)
Systematic name
hydrogenobyrinate-a,c-diamide:cobalt cobalt-ligase (ADP-forming)
CAS registry number
81295-49-0
Comment
This enzyme, which forms part of the aerobic (late cobalt insertion) cobalamin biosynthesis pathway, is a type I chelatase, being heterotrimeric and ATP-dependent. It comprises two components, one of which corresponds to CobN and the other is composed of two polypeptides, specified by cobS and cobT in Pseudomonas denitrificans, and named CobST [1]. Hydrogenobyrinate is a very poor substrate. ATP can be replaced by dATP or CTP but the reaction proceeds more slowly. CobN exhibits a high affinity for hydrogenobyrinate a,c-diamide. The oligomeric protein CobST possesses at least one sulfhydryl group that is essential for ATP-binding. See EC 4.99.1.3, sirohydrochlorin cobaltochelatase, for the cobaltochelatase that participates in the anaerobic cobalamin biosynthesis pathway.
History
created 2004
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1 Oxidoreductases
