Gene/Protein Disease Symptom Drug Enzyme Compound
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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.
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PMID:The effect of nitrogen limitation on catabolite repression of amidase, histidase and urocanase in Pseudomonas aeruginosa. 0 23

The arrangement of the histidine utilization (hut) genes in Pseudomonas putida was established by examining the structure of a DNA segment that had been cloned into Escherichia coli via a cosmid vector. Southern blot analysis revealed that the restriction patterns of the hut genes cloned into E. coli and present in the P. putida genome were identical, indicating that no detectable DNA rearrangement took place during the cloning. Expression of the hut genes from a series of overlapping clones indicated the gene order to be hutG-hutI-hutH-hutU-hutC-hutF. The transcription directions of the different hut genes were determined by cloning the genes under control of the lambda pL promoter. This showed that hutF, encoding formiminoglutamate hydrolase, was transcribed in a direction opposite to that of the other genes. Inactivation of the cloned hut genes by Tn1000 insertion revealed that the hut genes were divided into three major transcriptional units (hutF, hutC [the repressor gene], and hut UHIG), but hutG may also be independently transcribed. When cloned individually with hutC on the same vector, hutF and hutU (which encodes urocanase) expression was induced by urocanate, indicating that these two genes each possess an operator-promoter element. Tn1000 insertions (in the cloned genes) or Tn5 insertions (in the P. putida genome) affecting the hutI or hutH gene only partially eliminated hutG expression. Furthermore, hutG, which specifies N-formylglutamate amidohydrolase, was regulated by the hutC product when the two genes were cloned on the same vector and expressed in E. coli. Therefore, hutG can be expressed independently from its own promoter, in keeping with earlier observations that N-formylglutamate amidohydrolase synthesis is not coordinated with that of urocanase and histidase and can be induced by N-formylglutamate or urocanate.
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PMID:Organization and multiple regulation of histidine utilization genes in Pseudomonas putida. 284 9

Crc (catabolite repression control) protein of Pseudomonas aeruginosa has shown to be involved in carbon regulation of several pathways. In this study, the role of Crc in catabolite repression control has been studied in Pseudomonas putida. The bkd operons of P. putida and P. aeruginosa encode the inducible multienzyme complex branched-chain keto acid dehydrogenase, which is regulated in both species by catabolite repression. We report here that this effect is mediated in both species by Crc. A 13-kb cloned DNA fragment containing the P. putida crc gene region was sequenced. Crc regulates the expression of branched-chain keto acid dehydrogenase, glucose-6-phosphate dehydrogenase, and amidase in both species but not urocanase, although the carbon sources responsible for catabolite repression in the two species differ. Transposon mutants affected in their expression of BkdR, the transcriptional activator of the bkd operon, were isolated and identified as crc and vacB (rnr) mutants. These mutants suggested that catabolite repression in pseudomonads might, in part, involve control of BkdR levels.
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PMID:Crc is involved in catabolite repression control of the bkd operons of Pseudomonas putida and Pseudomonas aeruginosa. 1064 42

Vfr of Pseudomonas aeruginosa is 91% similar to the cAMP receptor protein (CRP) of Escherichia coli. Based on the high degree of sequence homology between the two proteins, the question arose whether Vfr had a global regulatory effect on gene expression for P. aeruginosa as CRP did for E. coli. This report provides two-dimensional polyacrylamide gel electrophoretic evidence that Vfr is a global regulator of gene expression in P. aeruginosa. In a vfr101::aacC1 null mutant, at least 43 protein spots were absent or decreased when compared to the proteome pattern of the parent strain. In contrast, 17 protein spots were absent or decreased in the parent strain when compared to the vfr101::aacC1 mutant. Thus, a mutation in vfr affected production of at least 60 proteins in P. aeruginosa. In addition, the question whether Vfr and CRP shared similar mechanistic characteristics was addressed. To ascertain whether Vfr, like CRP, can bind cAMP, Vfr and CRP were purified to homogeneity and their apparent dissociation constants (K(d)) for binding to cAMP were determined. The K(d) values were 1.6 microM for Vfr and 0.4 microM for CRP, suggesting that these proteins have a similar affinity for cAMP. Previously the authors had demonstrated that Vfr could complement a crp mutation and modulate catabolite repression in E. coli. This study presents evidence that Vfr binds to the E. coli lac promoter and that this binding requires the presence of cAMP. Finally, the possible involvement of Vfr in catabolite repression control in P. aeruginosa was investigated. It was found that succinate repressed production of mannitol dehydrogenase, glucose-6-phosphate dehydrogenase, amidase and urocanase both in the parent and in two vfr null mutants. This implied that catabolite repression control was not affected by the vfr null mutation. In support of this, the cloned vfr gene failed to complement a mutation in the P. aeruginosa crc gene. Thus, although Vfr is structurally similar to CRP, and is a global regulator of gene expression in P. aeruginosa, Vfr is not required for catabolite repression control in this bacterium.
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PMID:Effect of vfr mutation on global gene expression and catabolite repression control of Pseudomonas aeruginosa. 1198 31