Biosynthesis of vitamin B sub 12 : Isolation of precorrin-6x, a metal-free precursor of the corrin macrocycle retaining five S-adenosylmethionine-derived peripheral methyl groups

Journal Article · Wed Oct 31 23:00:00 EST 1990 · Proceedings of the National Academy of Sciences of the United States of America; (United States)

DOI:https://doi.org/10.1073/pnas.87.22.8795· OSTI ID:5822247

Thibaut, D; Debussche, L; Blanche, F ^[1]

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1. Centre de Rechereche de Vitry, Vitry-sur-Seine (France)

{delta}-Aminolevulinic acid and trimethylisobacteriochlorin are converted by cell-free protein preparations from pseudomonas denitrificans into a metal-free pigment, precorrin-6x. This pigment, which accumulates when the cell-free system lacks NADPH, can be enzymically converted in high yield (>50%) into hydrogenobyrinic acid by the complete enzyme preparation. Double-labeling experiments establish that precorrin-6x carries five C-methyl groups, which appear at C-1, C-2, C-7, C-12{alpha}, and C-17 of the hydrogenobyrinic acid formed enzymically from precorrin-6x. This precursor of the corrin macrocycle is at the dehydrocorrin level of oxidation, has undergone ring contraction and extrusion of C-20, but still carries the acetic acid side chain at C-12. It is demonstrated that the conversion of precorrin-6x into hydrogenobyrinic acid specifically requires and NADPH-dependent reduction step.

• OSTI ID: 5822247
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (United States), Journal Name: Proceedings of the National Academy of Sciences of the United States of America; (United States) Vol. 87:22; ISSN 0027-8424; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINO ACIDS
AMINOLEVULINIC ACID
BACTERIA
BIOSYNTHESIS
CARBON 14 COMPOUNDS
CARBON COMPOUNDS
CARBOXYLIC ACIDS
DOUBLE LABELLING
DRUGS
HEMATINICS
HEMATOLOGIC AGENTS
HYDROGEN COMPOUNDS
LABELLED COMPOUNDS
LABELLING
MICROORGANISMS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PIGMENTS
PSEUDOMONAS
SYNTHESIS
TRITIUM COMPOUNDS
VITAMIN B GROUP
VITAMIN B-12
VITAMINS