/sup 13/C nuclear magnetic resonance studies of the biosynthesis by Microbacterium ammoniaphilum of L-glutamate selectively enriched with carbon-13
/sup 13/C NMR of isotopically enriched metabolites has been used to study the metabolism of Microbacterium ammoniaphilum, a bacterium which excretes large quantities of L-glutamic acid into the medium. Biosynthesis from 90% (1-/sup 13/C) glucose results in relatively high specificity of the label, with (2,4-/sup 13/C/sub 2/) glutamate as the major product. The predominant biosynthetic pathway for synthesis of glutamate from glucose was determined to be the Embden Meyerhof glycolytic pathway followed by P-enolpyruvate carboxylase and the first third of the Krebs cycle. Different metabolic pathways are associated with different correlations in the enrichment of the carbons, reflected in the spectrum as different /sup 13/C-/sup 13/C scalar multiplet intensities. Hence, intensity and /sup 13/C-/sup 13/C multiplet analysis allows quantitation of the pathways involved. Although blockage of the Krebs cycle at the ..cap alpha..-ketoglutarate dehydrogenase step is the basis for the accumulation of glutamate, significant Krebs cycle activity was found in glucose grown cells, and extensive Krebs cycle activity in cells metabolizing (1-/sup 13/C) acetate. In addition to the observation of the expected metabolites, the disaccharide ..cap alpha..,..cap alpha..-trehalose and ..cap alpha..,..beta..-glucosylamine were identified from the /sup 13/C NMR spectra.
- Research Organization:
- Los Alamos National Lab., NM
- OSTI ID:
- 5177638
- Journal Information:
- J. Biol. Chem.; (United States), Vol. 257:3
- Country of Publication:
- United States
- Language:
- English
Similar Records
Formation of glutamine from (/sup 13/N)ammonia, (/sup 13/N)dinitrogen, and (/sup 14/C)glutamate by heterocysts isolated from Anabaena cylindrica
Examining Escherichia coli glycolytic pathways, catabolite repression, and metabolite channeling using Δpfk mutants
Related Subjects
CARBON 13
TRACER TECHNIQUES
GLUTAMIC ACID
BIOSYNTHESIS
BACTERIA
BIOLOGICAL PATHWAYS
ENZYME ACTIVITY
GLUCOSE
KREBS CYCLE
LABELLED COMPOUNDS
METABOLISM
METABOLITES
NUCLEAR MAGNETIC RESONANCE
ALDEHYDES
AMINO ACIDS
CARBOHYDRATES
CARBON ISOTOPES
CARBOXYLIC ACIDS
EVEN-ODD NUCLEI
HEXOSES
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
MICROORGANISMS
MONOSACCHARIDES
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
RESONANCE
SACCHARIDES
STABLE ISOTOPES
SYNTHESIS
550201* - Biochemistry- Tracer Techniques
550701 - Microbiology- Tracer Techniques