Enzymatic synthesis and structure of precorrin-3, a trimethyldipyrrocorphin intermediate in Vitamin B sub 12 biosynthesis
- Texas A and M Univ., College Station (United States)
The trimethylated intermediate of vitamin B{sub 12} (corrin) biosynthesis, precorrin-3, was produced from various {sup 13}C-enriched isotopomers of 5-aminolevulinic acid (ALA), using a multiple-enzyme system containing ALA dehydratase, porphobilinogen deaminase, uro'gen III synthetase, and the S-adenosyl-L-methionine- (SAM)-dependent uro'gen III methyltransferase (M-1) and precorrin-2 methyltransferase (M-2) in the presence of ({sup 13}C)SAM. Structural analysis of the resulting product, precorrin-3, reveals a close similarity to precorrin-2 but with several subtle differences in the conjugated array of C{double bond}C and C{double bond}N bonds which reflect the presence of the new C-methyl group at C20 and its influence on the electronic distribution in the dipyrrocorphin chromophore. The implications of this structure for corrin biosynthesis are discussed.
- OSTI ID:
- 5488978
- Journal Information:
- Biochemistry; (United States), Journal Name: Biochemistry; (United States) Vol. 31:2; ISSN 0006-2960; ISSN BICHA
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
59 BASIC BIOLOGICAL SCIENCES
BIOSYNTHESIS
CARBON 13
CARBON ISOTOPES
CARBON-GROUP TRANSFERASES
DRUGS
ENZYMES
EVEN-ODD NUCLEI
HEMATINICS
HEMATOLOGIC AGENTS
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
METHYL TRANSFERASES
NMR SPECTRA
NUCLEAR MAGNETIC RESONANCE
NUCLEI
ORGANIC COMPOUNDS
PROTEINS
REACTION INTERMEDIATES
RESONANCE
SPECTRA
STABLE ISOTOPES
SYNTHESIS
TRANSFERASES
ULTRAVIOLET SPECTRA
VISIBLE SPECTRA
VITAMIN B GROUP
VITAMIN B-12
VITAMINS