Disease relevance of ggt

• The processing mechanism for gamma-glutamyltranspeptidase of Escherichia coli K-12 has been analyzed by means of in vitro studies using purified precursors [1].
• Essential role of Helicobacter pylori gamma-glutamyltranspeptidase for the colonization of the gastric mucosa of mice [2].
• A mutant Bacillus subtilis gamma-glutamyltranspeptidase specialized in hydrolysis activity [3].
• gamma-Glutamyltranspeptidase (GGT) was purified from a Pseudomonas sp. strain A14 [4].

High impact information on ggt

• gamma-Glutamyltranspeptidase is the key enzyme in glutathione metabolism, and we previously presented evidence suggesting that it belongs to the N-terminal nucleophile hydrolase superfamily [1].
• The deduced amino acid sequence of the dep product has sequence similarity to E. coli and mammalian gamma-glutamyltranspeptidase (GGT) [5].
• gamma-Glutamyltranspeptidase (EC 2.3.2.2) is the enzyme involved in glutathione metabolism and catalyzes the hydrolysis and transpeptidation of gamma-glutamyl compounds such as glutathione and its derivatives [6].
• Identification of catalytic nucleophile of Escherichia coli gamma-glutamyltranspeptidase by gamma-monofluorophosphono derivative of glutamic acid: N-terminal thr-391 in small subunit is the nucleophile [6].
• This substitution enabled gamma-glutamyltranspeptidase to deacylate glutaryl-7-aminocephalosporanic acid, producing 7-aminocephalosporanic acid, which is a starting material for the synthesis of semisynthetic cephalosporins [7].

Chemical compound and disease context of ggt

• This transporter, along with gamma-glutamyltranspeptidase, has an important role in E. coli growth with glutathione as a sole sulfur source [8].
• Escherichia coli K-12 mutants lacking gamma-glutamyltranspeptidase (EC 2.3.2.2) were isolated after mutagenesis of cells with ethyl methanesulfonate [9].
• A truncated gene from Bacillus lichenifromis ATCC 27811 encoding a recombinant gamma-glutamyltranspeptidase (BLrGGT) was cloned into pQE-30 to generate pQE-BLGGT, and the overexpressed enzyme was purified from the crude extract of IPTG-induced E. coli M15 (pQE-BLGGT) to homogeneity by nickel-chelate chromatography [10].

Biological context of ggt

• A single amino acid substitution converts gamma-glutamyltranspeptidase to a class IV cephalosporin acylase (glutaryl-7-aminocephalosporanic acid acylase) [7].
• Ggt- phenotype of gamma-glutamyltranspeptidase-deficient mutants was complemented by pSH101 [11].
• A gamma-glutamyltranspeptidase-less mutant of E. coli K-12 was transformed with each plasmid or with both of them [12].
• The DNA sequence of gamma-glutamyltranspeptidase gene of Bacillus subtilis (natto) plasmid pUH1 [13].
• The gene of gamma-glutamyltranspeptidase encoded a signal peptide, and the large and small subunits in a single open reading frame in that order [12].

Anatomical context of ggt

• Gamma-glutamyltranspeptidase: disulfide bridges, propeptide cleavage, and activation in the endoplasmic reticulum [14].
• gamma-Glutamyltranspeptidase (gammaGT) is found primarily on the apical surface of epithelial and endothelial cells, where it degrades reduced and oxidized glutathione (gamma-GluCysGly) by hydrolysis of the unique gamma-glutamyl bond [14].
• Kinetic parameters (Km and Vmax) of renal brush border membrane (BBM) enzymes alkaline phosphatase, maltase, leucine aminopeptidase and gamma-glutamyltranspeptidase were worked out in control, infected and immunized-infected rats [15].
• Besides morphological changes, concentration of serotonin and histamine in liver homogenates, the activity of asparagine and alanine aminotransferases (AspAT, ALAT), gamma-glutamyltranspeptidase (GGTP) and alcohol dehydrogenase (ADH) in blood serum were determined, too [16].

Associations of ggt with chemical compounds

• An enzymatic method for synthesizing various gamma-D-glutamyl compounds efficiently and stereospecifically involving bacterial gamma-glutamyltranspeptidase (EC 2.3.2.2) with D-glutamine as a gamma-glutamyl donor was developed [17].
• The optimum reaction conditions were 50 mM D-glutamine, 50 mM L-tryptophan, and 0.2 U ml(-1) gamma-glutamyltranspeptidase, pH 9-9.5, and incubation at 37 degrees C for 5 h [18].
• Because the effect of gamma-glutamylization of bitter amino acids was most obvious for Phe, which is an atypical bitter amino acid, an enzymatic method for the synthesis of gamma-glutamylphenylalanine (gamma-Glu-Phe) involving bacterial gamma-glutamyltranspeptidase was developed [19].
• Development of an efficient enzymatic production of gamma-D-glutamyl-L-tryptophan (SCV-07), a prospective medicine for tuberculosis, with bacterial gamma-glutamyltranspeptidase [18].

Analytical, diagnostic and therapeutic context of ggt

• Crystallization and preliminary X-ray analysis of gamma-glutamyltranspeptidase from Escherichia coli K-12 [20].
• Molecular cloning of Escherichia coli K-12 ggt and rapid isolation of gamma-glutamyltranspeptidase [11].
• The processing phenotypes of six mutants were examined by Western blot analysis, and their gamma-glutamyltranspeptidase activities were measured [21].
• gamma-Glutamyltranspeptidase [EC 2.3.2.2] of Escherichia coli K-12 consists of one large subunit and one small subunit, which can be separated from each other by high-performance liquid chromatography [12].

References