Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.5.1.4 (deaminase)
 5,113 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In Pseudomonas aeruginosa, the synthesis of histidase, urocanase and amidase is severly repressed when succinate is added to a culture growing in pyruvate + ammonium salts medium. When growth is nitrogen-limited, catabolite repression by succinate of histidase and urocanase synthesis does not occur but succinate repression of amidase synthesis persists. Amidase synthesis is not regulated in the same way as histidase synthesis by the availability of other nitrogen compounds for growth. Growth of P. aeruginosa strain PACI in succinate + histidine media is nitrogen-limited since this strain is defective in a histidine transport system. When methyl-ammonium chloride is added to succinate + histidine media, growth inhibition occurs. Mutants isolated from succinate + histidine + methylammonium chloride plates were found to be resistant to catabolite repression by succinate even in ammonium salts media. It is suggested that the hut genes of P. aeruginosa may be regulated in the same way as in Klebsiella aerogenes, by induction by urocanate and activation by either the cyclic AMP-dependent activator protein or by glutamine synthetase.
J Gen Microbiol 1976 Apr
PMID:The effect of nitrogen limitation on catabolite repression of amidase, histidase and urocanase in Pseudomonas aeruginosa. 0 23

Hydroxyurea inhibited growth of Pseudomonas aeruginosa strain AI 3 on media containing either acetanilide (N-phenyl acetamide) or acetamide as sole carbon sources. Mutants resistant to hydroxyurea inhibition of growth on acetanilide (OUCH strains) and acetamide (AmOUCH strains) displayed altered growth properties on various amide media compared with the parent strain AI3. AI3 amidase, which catalyses the initial step in the metabolism of acetanilide and acetamide, was inhibited by hydroxyurea in a time-dependent reaction that was slowly reversible at pH 7.2. Compared with AI3 amidase, amidases from the OUCH mutants were much less sensitive to inhibition by hydroxyurea and showed altered substrate specificities and pH/activity profiles; amidases from the AmOUCH mutants were more sensitive to hydroxyurea inhibition but showed increased activity towards acetamide. Association of resistance to hydroxyurea inhibition with a mutation in the amidase structural gene of strain OUCH 4 was confirmed by transduction.
Mol Gen Genet 1978 Oct 04
PMID:Relationship between mutant amidases of Pseudomonas aeruginosa and hydroxyurea as an inhibitor. 10 40

A family of mutant amidases has been derived by experimental evolution of the aliphatic amidase of Pseudomonas aeruginosa strain PAC1. Mutation amiE16, in the structural gene for the enzyme, results in the production of the mutant B amidase by strain B6. This strain, unlike the wild-type, can utilize butyramide for growth. Strain B6 gave rise by a single mutational event to strain V9, utilizing valeramide, and strain PhB3, utilizing phenylacetamide. Strain V9 was not itself able to utilize phenylacetamide but gave rise by mutation to the phenylacetamide-utilizing mutant PhV1. Peptide 108 was isolated from chymotryptic digests of mutant amidases from strains B6, PhB3 and PhV1, but could not be detected in chymotryptic digests of the wild-type amidase. The sequence of peptide 108 was established as Met-Arg-His-Gly-Asp-Ile-Phe. Thermolytic digests of mutant amidases from strains B6, PhB3, PhV1 and V9 were compared with digests of the wild-type amidase. A peptide of the composition Met, Arg, His, Gly2, Asp3, Ile, Ser3, Thr, Val was found in the digest of the wild-type amidase and was replaced in the digests of the mutant amidases by a peptide of the composition Met, Arg, His, Gly2, Asp3, Ile, Ser3, Thr, Val, Phe. Mutation amiE16 is common to the four mutant enzymes and can be accounted for by the mutation Ser leads to Phe. The sequence of the chymotryptic peptide corresponds with the N-terminal sequence of the amidase protein, and can also be related to the thermolysin peptides. It is concluded that mutation amiE16 is a Ser leads to Phe change at position 7 from the N-terminus and the effect of this on the enzyme conformation is discussed.
J Gen Microbiol 1979 Sep
PMID:Molecular basis of altered enzyme specificities in a family of mutant amidases from Pseudomonas aeruginosa. 11 34

Synthesis of the Pseudomonas aeruginosa aliphatic amidase was repressed severely by succinate and malate and less severely by glucose, acetate or lactate. Amidase synthesis in inducible and constitutive strains was stimulated by cyclic AMP, which also gave partial relief to catabolite repression produced by the addition of lactate to cultures growing in pyruvate medium. Mutants which were resistant to catabolite repression were isolated from succinate+lactamide medium.
J Gen Microbiol 1975 Sep
PMID:Catabolite repression of Pseudomonas aeruginosa amidase: the effect of carbon source on amidase synthesis. 17 Mar 65

Among mutants of Pseudomonas aeruginosa isolated from fluoroacetamide medium were some which synthesized amidase at about 5% of the rate of the parent constitutive strain, PAC101. Seven fluoroacetamide-resistant mutants with low amidase activity gave rise to secondary mutant strains on succinate+butyramide plates. One appeared to be an 'up-promotor' mutant and synthesized amidase at a high rate. This mutant, PAC433, was not stimulated by cyclic-AMP and was much less sensitive to catabolite repression by succinate. The mutation conferring resistance to catabolite repression was cotransduced at a frequency of 96% (26/27) with the amidase genes amiR, amiE. Five other revertants had catabolite repression-resistance mutations which were linked to the amidase genes and these also were probably promotor mutants. One strain had a mutation conferring resistance to catabolite repression which was unlinked to the amidase genes.
J Gen Microbiol 1975 Sep
PMID:Catabolite repression of Pseudomonas aeruginosa amidase: isolation of promotor mutants. 17 Mar 66

We describe the regulatory properties of two strains carrying either the ilvA624 or the ilvA625 mutations, located in the structural gene for threonine deaminase. Crude extracts of both these strains possess a threonine deaminase activity migrating on polyacrylamide gels, differently from the wild type enzyme. Growth studies demonstrate that these mutations do not cause a limitation of isoleucine biosynthesis, suggesting normal catalytic activity of deaminase. A regulatory consequence of the ilvA624 allele is a derepression of the isoleucine-valine biosynthetic enzymes, which is recessive to an ilvA+ allele. The ilvA625 mutation causes a derepression which is dominant in an ilvA625/ILVA+ diploid. We interpret these data assuming that threonine deaminase, previously shown to be an autogenous regulator of the ilv genes, lacks a repressor function in the ilvA624 mutant, while in the ilvA625 mutant it is a better activator than wild type threonine deaminase. The data are discussed in terms of a model requiring that threonine deaminase, or a precursor of it, is in equilibrium between two forms, one being an activator of gene expression and the other being a repressor.
Mol Gen Genet 1978 Feb 07
PMID:Dual autogenous regulatory role of threonine deaminase in Escherichia coli K-12. 34 81

A thermophilic bacillus growing on acetamide as both carbon and nitrogen sources produces an inducible amidase. This amidase hydrolysed the following amides in decreasing order or activity, in comparison with acetamide (1.00): propionamide (0.97), fluoroacetamide (0.84), formamide (0.35) and glycinamide (0.12). Cyanoacetamide, dimethylacetamide, dimethylformamide and urea also induced the synthesis of the amidase, but were not substrates of the enzyme. Studies with protoplasts suggest that the amidase is located in the cytoplasm. Glucose strongly inhibited amidase synthesis; and limiting nitrogen did not release this inhibition. Urea strongly inhibited amidase activity in a competitive manner; but the inhibition caused by iodoacetamide and cyanoacetamide was non-competitive. Both thioacetamide and thiourea were effective inhibitors of enzyme induction. Bacteria grown on a succinate-minimal medium exhibited a lag in amidase synthesis, which could be eliminated by decreasing the concentration of succinate. Acetate- or pyruvate-grown cultures behaved similarly, while those grown on alanine or glutamate exhibited no lag in enzyme induction. In the mutant strain E21, repression of amidase synthesis by glucose was much less evident and no lag for induction was apparent with any of the other carbon sources mentioned.
J Gen Microbiol 1976 May
PMID:Regulatory properties of an inducible aliphatic amidase in a thermophilic bacillus. 93 86

A mutation in a gene designated gmdA has been found to lead to loss of ability of Aspergillus nidulans to use benzamide, phenylacetamide and several other amides as sole nitrogen sources for growth. The gmdA1 lesion results in low levels of an enzyme, called the general amidase, which has acitivity for a wide range of amide substrates. This enzyme is reressed by certain nitrogen-containing metabolites, including ammonium, but is probably not regulated by induction or by carbon catabolite repression. Evidence is presented for the general amidase being distinct from the previously characterized acetamidase and formamidase enzymes. The data also indicate that there is a fourth amidase capable of the hydrolysis of valeramide and hexanamide.
J Gen Microbiol 1975 Nov
PMID:Amide utilization in Aspergillus nidulans: evidence for a third amidase enzyme. 110 71

A bacterial strain, AEI, which hydrolysed acetanilide, was isolated from soil and identified as Pseudomonas acidovorans. Numerous amides, esters and enzyme inhibitors were tested as amidase inducers. Phenacetin was chosen as inducer for the large scale cultivation of these organisms because it was less toxic to the bacteria than acetanilide. The induction increased the enzymic activity 250-fold. In comparison, the type culture strain of P. acidovorans, ATTCCI5668, had no amidase activity which could be induced by phenacetin. Optimal growth conditions were established with respect to the concentration of carbon source and inducer so that about 10% of the extractable bacterial protein consisted of the amidase. The organisms were lysed with lysozyme in the presence of EDTA and the enzyme was isolated mainly by column chromatography procedures. A preparation form 60 g (wet wt) bacteria yielded about 100 mg highly purified amidase with a specific activity of 137 mugmol substrate hydrolysed/min/mg protien. In addition to acetanilide, the purified enzyme hydrolysed several other amides and esters. As standard substrate, p-nitroacetanilide was chosen.
J Gen Microbiol 1975 Apr
PMID:Isolation of an inducible amidase from Pseudomonas acidovorans AE1. 114 56

The regulatory unit of Bacillus subtilis strain 168 encompassing the structural genes of the N-acetylmuramoyl-L-alanine amidase and of its modifier has been sequenced, and found to be a divergon consisting of divergently transcribed operons lytABC and lytR. Proteins LytA, LytB and LytC are endowed with export signal peptides. Mature LytA is a 9.4 kDa, highly acidic polypeptide whose deduced amino acid sequence points to a lipoprotein. LytB and LytC, the modifier and the amidase, are highly basic. After cleavage of the signal sequence their molecular masses are 74.1 and 49.9 kDa, respectively. These two proteins share considerable homology in their N-terminal moieties and have three GSNRY consensus motifs, characteristic of nearly all amidases. The C-terminal moiety of LytB exhibits homology to the product of spoIID. LytR is a 35 kDa protein which acts as an attenuator of the expression of both lytABC and lytR operons. Transcription of the lytABC operon proceeds from two promoters: PD, identified as P28-7 (Gilman et al., 1984), and an upstream PA. The former only is subject to LytR attenuation. Translational initiation of lytB and lytC is directed by UUG start codons, suggesting that lytA, B and C undergo coupled translation. Transcription of lytR is initiated at two start sites, one of which corresponds to a highly intense PA promoter whereas the other does not seem to share much homology with any of the known promoter consensus sequences. Both promoters are attenuated by LytR. It is confirmed that the synthesis of the amidase is controlled at least in part by SigD, i.e. that it belongs to the fla regulon and that its activity, or part of it, is co-regulated with flagellar motility. The role of the mutations conferring the Sin, Fla and Ifm phenotypes in the expression of the lytABC operon is discussed.
J Gen Microbiol 1992 Sep
PMID:Sequencing and analysis of the Bacillus subtilis lytRABC divergon: a regulatory unit encompassing the structural genes of the N-acetylmuramoyl-L-alanine amidase and its modifier. 135 79


1 2 3 4 5 6 Next >>