CbiD is essential for cobalamin biosynthesis in both S. typhimurium and B. megaterium, no functional role has been ascribed to the protein. The CbiD protein has a putative S-AdoMet binding site. It is possible that CbiD might have the same role as CobF in undertaking the C-1 methylation and deacylation reactions required during the ring contraction process.
Jiyao W et al.(2023). "The conserved domain database in 2023.",