Disease relevance of guaA

• Effects of xapA and guaA Disruption on Inosine Accumulation in Escherichia coli [1].
• Characterization of LtsA from Rhodococcus erythropolis, an enzyme with glutamine amidotransferase activity [2].

High impact information on guaA

• The Class I glutamine amidotransferase domain of GMP synthetase is found in related enzymes of the purine, pyrimidine, tryptophan, arginine, histidine and folic acid biosynthetic pathways [3].
• PLP synthase is a heteromeric glutamine amidotransferase in which PdxT produces ammonia from glutamine and PdxS combines ammonia with five- and three-carbon phosphosugars to form PLP [4].
• Anthranilate synthase is a glutamine amidotransferase that catalyzes the first reaction in tryptophan biosynthesis [5].
• Nucleotide sequence of the guaA gene encoding GMP synthetase of Escherichia coli K12 [6].
• The amino acid sequence of the NH2 terminus of GMP synthetase was determined and used to verify the translation start site determined from the DNA sequence [6].

Chemical compound and disease context of guaA

• Crystal structure of Escherichia coli cytidine triphosphate synthetase, a nucleotide-regulated glutamine amidotransferase/ATP-dependent amidoligase fusion protein and homologue of anticancer and antiparasitic drug targets [7].
• Escherichia coli pabA encodes the glutamine amidotransferase subunit of p-aminobenzoate synthase. p-Aminobenzoate synthase catalyzes the conversion of chorismate and glutamine to 4-amino-4-deoxychorismate, which is then converted to p-aminobenzoate by a 4-amino-4-deoxychorismate lyase [8].
• GAT-containing proteins include many biosynthetic enzymes such as E. coli carbamoyl phosphate synthetase and anthranilate synthase [9].
• Combined, functional genomic-biochemical approach to intermediary metabolism: interaction of acivicin, a glutamine amidotransferase inhibitor, with Escherichia coli K-12 [10].

Biological context of guaA

• PCR-mediated deletion mutagenesis and cloning identified a 120-bp fragment upstream from the guaA gene to be the actual regulator [11].
• Primer extension analysis mapped the transcription start site to be the first 'G' residue of the translation start codon GTG of the guaA gene [11].
• Alkylation of GMP synthetase with iodacetamide selectively inactivated glutamine-dependent activity [12].
• Glutamine amidotransferase function. Replacement of the active-site cysteine in glutamine phosphoribosylpyrophosphate amidotransferase by site-directed mutagenesis [13].
• GMP synthetase catalyzes the hydrolysis of ATP to AMP and PPi along with an ATP/PPi exchange reaction in the absence of NH3 [14].

Associations of guaA with chemical compounds

• The mechanism of inhibition of GMP synthetase by purine and purine-analog nucleosides was investigated [15].
• Alkylation of guanosine 5'-monophosphate (GMP) synthetase with the glutamine analogs L-2-amino-4-oxo-5-chloropentanoic acid (chloroketon) and 6-diazo-5-oxonorleucine (DON) inactivated glutamine- and NH3-dependent GMP synthetase [12].
• Iodoacetamide inactivates glutaminase concomitant with glutamine-dependent GMP synthetase [12].
• Imidazole glycerol phosphate synthase: the glutamine amidotransferase in histidine biosynthesis [16].
• In the first step, a glutamine amidotransferase encoded by the pabA gene generates ammonia as a substrate that, along with chorismate, is used in the second step, catalyzed by aminodeoxychorismate synthase, the product of the pabB gene [17].

Other interactions of guaA

• The structure reveals a nearly symmetric 222 tetramer, in which each bifunctional monomer contains a dethiobiotin synthetase-like amidoligase N-terminal domain and a Type 1 glutamine amidotransferase C-terminal domain [7].
• GMP and dGMP labeled with 15N at the 2-amino group of the purine ring was obtained enzymatically from NH4Cl (> 99 at.% 15N) and from IMP or dIMP, respectively, by several reactions involving IMP-dehydrogenase, GMP-synthetase, adenylate kinase, and creatine kinase [18].

References