. "The chemical reactions and pathways resulting in the formation of cobalamin (vitamin B12), a water-soluble vitamin characterized by possession of a corrin nucleus containing a cobalt atom." . . . . "cobalamin biosynthesis" . "cobalamin biosynthetic process" . "cobalamin anabolism" . "cobalamin formation" . "cobalamin synthesis" . "vitamin B12 biosynthesis" . "vitamin B12 biosynthetic process" . . . . .