Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q96DG6 (Pseudomonas)
 76,258 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. The existence of two different D-glucose-6-phosphate dehydrogenases in Pseudomonas fluorescens has been demonstrated. Based on their different specificity and their different metabolic regulation one enzyme is appointed to the Entner-Doudoroff pathway and the other to the hexose monophosphate pathway. 2. A procedure is described for the isolation of that D-glucose-6-phosphate dehydrogenase which forms part of the Entner-Doudoroff pathway (Entner-Doudoroff enzyme). A 950-fold purification was achieved with an overall yield of 44%. The final preparation, having a specific activity of about 300 mumol NADH formed per min per mg protein, was shown to be homogeneous. 3. The molecular weight of the Entner-Doudoroff enzyme has been determined to be 220000 by gel permeation chromatography, and that of the other enzyme (Zwischenferment) has been shown to be 265000. 4. The pI of the Entner-Doudoroff enzyme has been shown to be 5.24 and that of the Zwischenferment 4.27. The Entner-Doudoroff enzyme is stable in the range of pH 6 to 10.5 and shows its maximal activity at pH 8.9. 5. The Entner-Doudoroff enzyme showed specificity for NAD+ as well as for NADP+ and exhibited homotropic effects for D-glucose 6-phosphate. It is inhibited by ATP which acts as a negative allosteric effector. Other nucleoside triphosphates as well as ADP are also inhibitory. 6. The enzyme catalyzes the transfer of the axial hydrogen at carbon-1 of beta-D-glucopyranose 6-phosphate to the si face of carbon-4 of the nicotinamide ring and must be classified as B-side stereospecific dehydrogenase.
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PMID:D-glucose-6-phosphate dehydrogenase (Entner-Doudoroff enzyme) from Pseudomonas fluorescens. Purification, properties and regulation. 0 Dec 57

The pyruvate carboxylase of Pseudonomas fluorescens was purified 160-fold from cells grown on glucose at 20 degrees C. The activity of this purified enzyme was not affected by acetyl-coenzyme A or L-aspartate, but was strongly inhibited by ADP, which was competitive towards ATP. Pyruvate gave a broken double reciprocal plot, from which two apparent Km values could be determined, namely 0-08 and 0-21 mM, from the lower and the higher concentration ranges, respectively. The apparent Km for HCO3 at pH 6-9, in the presence of the manganese ATP ion (MnATP2-), was 3-1 mM. The enzyme reaction had an optimum pH value of 7-1 or 9-0 depending on the use of MnATP2- or MgATP2-, respectively, as substrate. Free Mg2+ was an activator at pH values below 9-0. The enzyme was strongly activated by monovalent cations; NH4+ and K+ were the better activators, with apparent Ka values of 0-7 and 1-6 mM, respectively. Partially purified enzymes from cells grown on glucose at 1 or 20 degrees C had the same properties, including the thermal stability. In both cases 50% of the enzyme activity was lost after pre-incubation for 10 min at 46 degrees C. The molecular weight was estimated to be about 300000 daltons by gel filtration on Sephadex G-200. The regulatory properties and molecular weight are thus similar to those determined for the pyruvate carboxylases from Pseudomonas citronellolis and Azotobacter vinelandii.
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PMID:Some properties of the pyruvate carboxylase from Pseudomonas fluorescens. 0 79

Two strains of Escherichia coli and one strain each of Salmonella typhimurium and Pseudomonas aeruginosa were killed by the bactericidal activity of the lactoperoxidase-thiocyanate-hydrogen peroxide system in milk and in a synthetic medium. H2O2 was supplied exogenously by glucose oxidase, and glucose was produced at a level which was itself noninhibitory. Two phases were distinguished: the first phase was dependent on the oxidation of SCN(-) by lactoperoxidase and H2O2, which was reversed by reducing agent, and the second phase was dependent on the presence of accumulated H2O2, which was reversed by catalase. The latter enzyme could also reverse the first phase, but only when present in excessive and unphysiological levels. The bactericidal activity was greatest at pH 5 and below, and it depended on the SCN(-)concentration and on the number of organisms. Since raw or heated milk neutralizes the acid barrier against infection in the stomach, the bactericidal system discussed may contribute to the prevention of enteric infections in neonates.
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PMID:Nonspecific bactericidal activity of the lactoperoxidases-thiocyanate-hydrogen peroxide system of milk against Escherichia coli and some gram-negative pathogens. 0 74

Crystalline glutaminase-asparaginase which is effective against solid as well as ascites tumors was prepared from soil isolate organism Pseudomonas 7A. This enzyme has a ration of Vmax for L-glutamine and L-asparagine of 2.0. The presence of glutamic acid in the growth medium is essential for optimal enzyme production and glucose inhibits the production of glutaminase-asparaginase. The purification procedure provides an overall yield of 40 to 45% from crude cell extract to homogeneous glutaminase-asparaginase and is adaptable to large scale production of the enzyme. The specific activity of homogeneous enzyme is 160 +/- 15 i.u./mg of protein and the E1% 280 is 9.8. No disulfide or sulfhydryl groups appear to be present on the enzyme. The isoelectric point of glutaminase-asparaginase by isoelectric focusing on ampholine polyacrylamide gel plates is 5.8. The Km values for L-glutamine and L-asparagine are 4.6 and 4.4 X 10(-6) M, respectively. The enzyme catalyzes the hydrolysis of the D isomers of glutamine and asparagine at 87 and 69% the rate of the respective L isomers. L-Glutamic acid gamma-monohydroxamate is hydrolyzed at approximately the same rate as L-glutamine. The enzyme is not inhibited by ethylenediaminetetraacetate (0.1 mM), L-glutamate (30 mM), or L-aspartate (30 mM). Ammonium sulfate (10 mM) inhibits the enzymatic activity. The plasma half-life of Pseudomonas 7A glutaminase-asparaginase if 13 hours in normal mice and 43 hours in mice infected with the lactate dehydrogenase-elevating virus.
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PMID:Purification and properties of a highly potent antitumor glutaminase-asparaginase from Pseudomonas 7Z. 0 41

A freshwater Pseudomonas sp. was grown in continuous culture under steady-state conditions in L-lactate-, succinate-, glucose- or ammonium-limited media. Under carbon limitation, the NAD(H) (i.e. NAD + NADH) concentration of the organisms increased exponentially from approximately 2 to 7 mumol/g dry wt as the culture dilution rate (D) was decreased from 0.5 to 0.02 h-1. Organisms grown at a given D in any of the carbon-limited media possessed very similar levels of NAD(H). Therefore, under these conditions, cellular NAD(H) was only a function of the culture O and was independent of the nature of the culture carbon source. D had no influence on the NAD(H) content of cells grown under ammonium limitation. In contrast, cellular NADH concentration was not influenced by D in carbon- or ammonium-limited media. In L-lactate-limited medium, bacteria possessed 0.14 mumol NADH/g dry wt; very similar levels were found in organisms grown in the other media. The results are consistent with those of Wimpenny & Firth (1972) that bacteria rigidly maintain a constant NADH level rather than a constant constant NADH: NAD ratio. NADP(H) (i.e. NADP + NADPH) and NADPH levels were also not influenced by changes in the culture carbon source or in D; in L-lactate-limited medium these concentrations were 0.97 and 0.53 mumol/g cell dry wt, respectively. The NADPH:NADP(H) ratio was much higher than the NADH:NAD(H) ratio, averaging 55% in carbon-limited cells.
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PMID:Influence of dilution rate on NAD(P) and NAD(P)H concentrations and ratios in a Pseudomonas sp. grown in continuous culture. 0 37

The hydrolysis of o-nitrophenyl-beta-D-galactopyranoside (ONPG) by BAL-31, a marine Pseudomonas that acts as a host for bacteriophage PM2, was studied with intact cells and with cell-free extracts. A transport system for ONPG in whole cells and a beta-galactosidase activity in extracts were evident for cells grown on lactose minimal medium. It was found that the addition of isopropylthio-beta-D-galactopyranoside (IPTG) to cells growing in rich medium induced an ONPG hydrolytic activity detectable in cell extracts but cryptic in whole cells. The existence of a transport system for IPTG, which remained cryptic for ONPG, became apparent from studies of the rates of induction of beta-galactosidase as a function of cell mass at different concentrations of IPTG. The main properties of beta-galactosidase and the lactose transport system of BAL-31 were studied in terms of how they were affected by pH, temperature, or by the presence of several sugars. IPTG competitively inhibits the hydrolysis of ONPG by cell extracts. In cells pregrown on lactose, IPTG slightly inhibits the transport of ONPG. Glucose, and with less efficiency lactose, also inhibits the hydrolysis of ONPG in cell extracts. The growth of cells on lactose minimal medium was inhibited by the addition of IPTG. A mechanism for this inhibition and for the inhibition of ONPG transport by IPTG is discussed.
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PMID:Induction and general properties of beta-galactosidase and beta-galactoside permease in Pseudomonas BAL-31. 1 11

Metabolism of lactate as a carbon source by Pseudomonas citronellolis occurred via a nicotinamide adenine dinucleotide (NAD)-independent L-lactate dehydrogenase, which was present in cells grown on DL-lactate but was not present in cells grown on acetate, aspartate, citrate, glucose, glutamate, or malate. The cells also possessed a constitutive, NAD-independent malate dehydrogenase instead of the conventional NAD-dependent malate dehydrogenase instead of the conventional NAD-dependent enzyme in the tricarboxylic acid cycle. Both enzymes were particulate and used dichlorophenolindo-phenol or oxygen as an electron acceptor. In acetate-grown cells, the activity of pyruvate dehydrogenase and NAD phosphate-linked malate enzyme decreased, cells grown on glucose or lactate. This was consistent with the need to maintain a supply of oxalacetate for metabolism of acetate via the tricarboxylic acid cycle. Changes in enzyme activities suggest that gluconeogenesis from noncarbohydrate carbon sources occurs via the malate enzyme (when oxalacetate decarboxylase is inhibited) or a combination of the NAD-independent malate dehydrogenase and oxalacetate decarboxylase.
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PMID:Formation and dissimilation of oxalacetate and pyruvate Pseudomonas citronellolis grown on noncarbohydrate substrates. 1 74

Enzymes catalyzing steps from ethanol to acetyl-coenzyme A, from malate to pyruvate, and from pyruvate to glucose 6-phosphate were identified in ethanol-grown Pseudomonas indigofera. Enzymes catalyzing the catabolism of glucose to pyruvate via the Entner-Doudoroff pathway were identified in glucose-grown cells. Phosphofructokinase could not be detected in Pseudomonas indigofera. Itaconate, a potent inhibitor of isocitrate lyase, abolished growth of P. indigofera on ethanol at concentrations that had little effect upon growth on glucose. The date obtained through enzyme analyses and studies of itaconate inhibition with both extracts and toluene-treated cells suggest that itaconate selectively inhibits and reduces the specific activity of isocitrate lyase.
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PMID:Itaconate, an isocitrate lyase-directed inhibitor in Pseudomonas indigofera. 1 93

Fermentation studies using batch culture indicated that exopolysaccharide production by Pseudomonas NCIBI1264 in a chemically defined medium increased under conditions of nitrogen limitation and excess carbon substrate at pH values above 6. The polysaccharide was formed from a variety of carbon substrates and its composition was not affected by the nature of the carbohydrate source. Polysacharide formation did not increase in media containing small amounts of phosphate, and, as in secondary metabolite production, it started late in the exponential growth phase continuing maximally after growth had ceased. The efficiency of glucose conversion into exopolysaccharide was low. Colorimetric, viscometric, and total carbon estimation techniques are described for determining exopolysaccharide levels in cell-free culture supernatants.
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PMID:Exopolysaccharide production by Pseudomonas NCIB11264 grown in batch culture. 2 Dec 24

Exopolysaccharide formation by Pseudomonas NCIB11264 in a single-stage continuous culture was maximal under nitrogen limitation with excess carbohydrate substrate at 30 +/- 1 degrees C and pH 7.0 +/- 0.1. Polysaccharide production was not enhanced by phosphate limitation but was dependent on the dilution rate. Steady states were maintained for up to 500 h without deterioration of the culture or the development of mutant strains. The efficiency of conversion of the glucose substrate utilized into exopolysaccharide by the chemostat cultures was as high as 73%.
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PMID:Exopolysaccharide production by Pseudomonas NCIB11264 grown in continuous culture. 2 85


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