Biomaterial Database

Oxidation of the active site of glutamine synthetase: conversion of arginine-344 to gamma-glutamyl semialdehyde. 1991

I Climent, and R L Levine

Laboratory of Biochemistry, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892.

Metal-catalyzed oxidative modification of proteins is implicated in a number of physiologic and pathologic processes. The reaction is presumed to proceed via a site-specific free radical mechanism, with the site-specificity conferred by a cation-binding site on the protein. The oxidation of bacterial glutamine synthetase has been studied in detail, providing the opportunity to examine whether the oxidation is consistent with a site-specific radical reaction. Oxidation leads to the appearance of carbonyl groups in amino acid side chains of the protein, and labeling of those carbonyl groups with fluorescein-amine facilitated purification of the oxidized peptide from a tryptic digest. The oxidized residue was arginine-344, which was converted to a gamma-glutamyl semialdehyde residue. Histidine-269 had previously been shown to be converted to asparagine during metal-catalyzed oxidation. Both arginine-344 and histidine-269 are situated at the metal-nucleotide binding pocket of the enzyme's active site, thus establishing the site-specificity of the oxidation.

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D010084	Oxidation-Reduction	A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).	Redox,Oxidation Reduction
D010446	Peptide Fragments	Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.	Peptide Fragment,Fragment, Peptide,Fragments, Peptide
D005456	Fluorescent Dyes	Chemicals that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.	Flourescent Agent,Fluorescent Dye,Fluorescent Probe,Fluorescent Probes,Fluorochrome,Fluorochromes,Fluorogenic Substrates,Fluorescence Agents,Fluorescent Agents,Fluorogenic Substrate,Agents, Fluorescence,Agents, Fluorescent,Dyes, Fluorescent,Probes, Fluorescent,Substrates, Fluorogenic
D005971	Glutamates	Derivatives of GLUTAMIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the 2-aminopentanedioic acid structure.	Glutamic Acid Derivatives,Glutamic Acids,Glutaminic Acids
D005974	Glutamate-Ammonia Ligase	An enzyme that catalyzes the conversion of ATP, L-glutamate, and NH3 to ADP, orthophosphate, and L-glutamine. It also acts more slowly on 4-methylene-L-glutamate. (From Enzyme Nomenclature, 1992) EC 6.3.1.2.	Glutamine Synthetase,Glutamate Ammonia Ligase (ADP),Glutamate Ammonia Ligase,Ligase, Glutamate-Ammonia,Synthetase, Glutamine
D006639	Histidine	An essential amino acid that is required for the production of HISTAMINE.	Histidine, L-isomer,L-Histidine,Histidine, L isomer,L-isomer Histidine
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D001120	Arginine	An essential amino acid that is physiologically active in the L-form.	Arginine Hydrochloride,Arginine, L-Isomer,DL-Arginine Acetate, Monohydrate,L-Arginine,Arginine, L Isomer,DL Arginine Acetate, Monohydrate,Hydrochloride, Arginine,L Arginine,L-Isomer Arginine,Monohydrate DL-Arginine Acetate
D001419	Bacteria	One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.	Eubacteria