Biosynthetic preparation of L-(/sup 13/C)- and (/sup 15/N)glutamate by Brevibacterium flavum

Journal Article · Thu Jan 01 00:00:00 EST 1987 · Appl. Environ. Microbiol.; (United States)

OSTI ID:6859915

Walker, T E; London, R E

The biosynthesis of isotopically labeled L-glutamic acid by the microorganism Brevibacterium flavum was studied with a variety of carbon-13-enriched precursors. The purpose of this study was twofold: (i) to develop techniques for the efficient preparation of labeled L-glutamate with a variety of useful labeling patterns which can be used for other metabolic studies, and (ii) to better understand the metabolic events leading to label scrambling in these strains. B. flavum, which is used commercially for the production of monosodium glutamate, has the capability of utilizing glucose or acetate as a sole carbon source, and important criterion from the standpoint of developing labeling strategies. Unfortunately, singly labeled glucose precursors lead to excessive isotopic dilution which reduces their usefulness. Studies with (3-/sup 13/C)pyruvate indicate that this problem can in principle be overcome by using labeled three-carbon precursors; however, conditions could not be found which would lead to an acceptable yield of isotopically labeled L-glutamate. In contrast, (1-/sup 13/C)- or (2-/sup 13/C)acetate provides relatively inexpensive, readily available precursors for the production of selectively labeled, high enriched L-glutamate. The preparation of L-(/sup 15/N)glutamate from (/sup 15/N)ammonium sulfate was carried out and is a very effective labeling strategy. Analysis of the isotopic distribution in labeled glutamate provides details about the metabolic pathways in these interesting organisms.

• Research Organization: Los Alamos National Lab., NM
• OSTI ID: 6859915
• Journal Information: Appl. Environ. Microbiol.; (United States), Vol. 53:1
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
BACTERIA
METABOLISM
GLUTAMIC ACID
BIOSYNTHESIS
LABELLING
BIOLOGICAL PATHWAYS
CARBON 13
ISOTOPE RATIO
NITROGEN 15
PRECURSOR
AMINO ACIDS
CARBON ISOTOPES
CARBOXYLIC ACIDS
EVEN-ODD NUCLEI
ISOTOPES
LIGHT NUCLEI
MICROORGANISMS
NITROGEN ISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
STABLE ISOTOPES
SYNTHESIS
550201* - Biochemistry- Tracer Techniques
550701 - Microbiology- Tracer Techniques