/iron-sulfur protein methyltransferase (MeTr)
نویسنده
چکیده
The methyltetrahydrofolate:corrinoid/iron-sulfur protein methyltransferase (MeTr) enzyme was originally isolated from the acetogenic bacteria Moorella (formerly Clostridium) thermoaceticum [612]. This bacterium, as some other anaerobic organisms, can obtain its entire carbon and energy source from CO or H2/CO2 by the Wood-Ljungdahl or acetyl-CoA pathway [613-615]. Initially, CO2 is reduced to formate and converted to N5-methyltetrahydrofolate (CH3THF) by a formate dehydrogenase and a series of four different tetrahydrofolate (THF)-dependent enzymes. Then, MeTr catalyses the transfer of the methyl group of CH3THF to the cobalt centre of a corrinoid/iron-sulfur protein (C/Fe-SP). Afterwards, the methyl group is transferred from cob(III)amide to CO dehydrogenase/acetyl-CoA synthase (CODH/ACS) to form a methylnickel intermediate [616], which finally combines with a Fe-CO species [617,618] and CoA to form acetyl-CoA.
منابع مشابه
Transient B12-Dependent Methyltransferase Complexes Revealed by Small-Angle X-ray Scattering
In the Wood-Ljungdahl carbon fixation pathway, protein-protein interactions between methyltransferase (MeTr) and corrinoid iron-sulfur protein (CFeSP) are required for the transfer of a methyl group. While crystal structures have been determined for MeTr and CFeSP both free and in complex, solution structures have not been established. Here, we examine the transient interactions between MeTr an...
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