<p>In <taxon tax_id="99287">Salmonella typhimurium LT2</taxon>, under anaerobic conditions, CobU (<db_xref db="EC" dbkey="2.7.7.62"/> and <db_xref db="EC" dbkey="2.7.1.156"/>), CobT (<db_xref db="EC" dbkey="2.4.2.21"/>), CobC (<db_xref db="EC" dbkey="3.1.3.73"/>) and CobS (<db_xref db="EC" dbkey="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 into its riboside, alpha-ribazole. The second branch of the nuclotide loop assembly pathway is the cobinamide (Cbi) activation branch where AdoCbi or adenosylcobinamide-phosphate is converted into the activated intermediate AdoCbi-GDP by the bifunctional enzyme CobU. CobS catalyses the final step in adenosylcobalamin biosynthesis, which is the condensation of AdoCbi-GDP with alpha-ribazole to yield adenosylcobalamin.</p><p>Members of this entry include the known CobC protein of Salmonella and <taxon tax_id="562">Escherichia coli</taxon> species, and homologous proteins found in cobalamin biosynthesis regions in other bacteria. CobC is alpha-ribazole phosphatase (<db_xref db="EC" dbkey="3.1.3.73"/>) and, like many phosphatases, can be closely related in sequence to other phosphatases with different functions. Close homologues excluded from this entry include proteins with duplications.</p> Alpha-ribazole phosphatase, CobC