Biosynthesis of Heme and Vitamin B12

摘要: The biosyntheses of the modified tetrapyrroles heme and adenosylcobalamin are outlined. two compounds made via a branched biosynthetic pathway that forks at first macrocyclic intermediate uroporphyrinogen III. For synthesis, modification peripheral acetate propionate side chains, oxidation, ferrochelation yields heme. In contrast, an extensive program methylation, cobalt insertion, chain amidation, ring contraction, decarboxylation, attachment upper lower axial ligands for ion required cobalamin synthesis. This review outlines individual steps in molecular detail reflects on range different chemistries enzymes involved making these essential metalloprosthetic groups.