Transferases;
Transferring phosphorus-containing groups;
Transferases for other substituted phosphate groups
BRITE hierarchy

adenosylcobinamide-GDP:alpha-ribazole ribazoletransferase

(1) adenosylcobinamide-GDP + alpha-ribazole = GMP + adenosylcobalamin [RN:R05223];
(2) adenosylcobinamide-GDP + alpha-ribazole 5'-phosphate = GMP + adenosylcobalamin 5'-phosphate [RN:R11174]

R05223 R11174
Reaction

adenosylcobinamide-GDP [CPD:C06510];
alpha-ribazole [CPD:C05775];
alpha-ribazole 5'-phosphate [CPD:C04778]

In Salmonella typhimurium LT2, under anaerobic conditions, CobU (EC 2.7.7.62 and EC 2.7.1.156), CobT (EC 2.4.2.21), CobC (EC 3.1.3.73) and CobS (EC 2.7.8.26) catalyse reactions in the nucleotide loop assembly pathway, which convert adenosylcobinamide (AdoCbi) into adenosylcobalamin (AdoCbl). CobT and CobC are involved in 5,6-dimethylbenzimidazole activation whereby 5,6-dimethylbenzimidazole is converted to its riboside, alpha-ribazole. The second branch of the nucleotide loop assembly pathway is the cobinamide activation branch where AdoCbi or adenosylcobinamide-phosphate is converted to the activated intermediate AdoCbi-GDP by the bifunctional enzyme Cob U. CobS catalyses the final step in adenosylcobalamin biosynthesis, which is the condensation of AdoCbi-GDP with alpha-ribazole to yield adenosylcobalamin.

EC 2.7.8.26 created 2004