Description | Cobalt-precorrin-5A hydrolase CbiG is specific for anaerobic cobalamin (vitamin B12) biosynthesis. CbiG, which shows homology with CobE of the aerobic pathway, participates in the conversion of cobalt-precorrin 5 into cobalt-precorrin 6 [ ]. CbiG is responsible for the opening of the delta-lactone ring and extrusion of the C2-unit []. The aerobic pathway uses molecular oxygen to trigger the events at C-20 leading to contraction and expulsion of the C2-unit as acetic acid from a metal-free intermediate, whereas the anaerobic route involves the internal delivery of oxygen from a carboxylic acid terminus to C-20 followed by extrusion of the C2-unit as acetaldehyde, using cobalt complexes as substrates [].This entry represents a domain found at the C terminus of CibG. CobE is composed solely of this domain. | Name | CobE/GbiG C-terminal domain |
Short Name | CobE/GbiG_C | Type | Domain |