FIG. 1.

Late steps in corrin ring biosynthesis in Salmonella enterica. Shown is a model of the enzymatic reactions needed for nucleotide loop assembly in S. enterica. Shown are the enzymes, substrates, and intermediates in the pathway. Abbreviations: AdoCby, adenosylcobyric acid; AdoCbi, adenosylcobinamide; AdoCbl, adenosylcobalamin; α-DAD, α-5,6-dimethylbenzimidazole adenine dinucleotide; Nm, nicotinamide; AP, aminopropanol; AP-P, aminopropanol phosphate; CbiB, putative AdoCbi-phosphate synthase; CobU, AdoCbi kinase and guanylyltransferase; CobT, NaMN:5,6-dimethylbenzimidazole phosphoribosyltransferase; CobS, adenosylcobalamin synthase; CobC (CobZ in M. mazei), α-ribazole-phosphate phosphatase; CbiZ, amidohydrolase. Archaeal enzymes are boxed.