Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20020 (adenosine triphosphatase)
 3,299 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Penetration of substrates into marine bacteria as influenced by cations has been demonstrated by the effects of increased osmotic pressure in spheroplasts of these cells. Spheroplasts of Pseudomonas natriegens, stabilized with lactose, underwent a metabolic swelling in the presence of a substrate to which they had been induced. Maximal and persistent swelling was achieved only by addition of catabolizable substrate and both Na(+) and K(+). Addition, along with substrate, of Na(+) alone or K(+) alone did not stimulate swelling; no metabolic swelling occurred in the presence of a sugar to which the cells had not been induced. Confirmation of rapid uptake by induced cells of the inducer sugar, l-arabinose, but not the d-isomer, was obtained with (14)C-labeled substrate. Addition of NaN(3) completely inhibited swelling, and 2, 4-dinitrophenol and ouabain each suppressed it by 50%, indicating requirement for energy metabolism and involvement of an adenosine triphosphatase in the penetration phenomena of these cells.
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PMID:Influence of cations on spheroplasts of marine bacteria functioning as osmometers. 603 44

A gentamicin-resistant mutant of Pseudomonas aeruginosa PAO503 was selected after ethyl methane sulfonate mutagenesis. The strain, P. aeruginosa PAO2401 had increased resistance to all aminoglycosides tested but exhibited no change for other antibiotics. The mutation designated aglA (aminoglycoside resistance) was 50% cotransducible with the 8-min ilvB,C marker on the P. aeruginosa chromosome. It showed a marked reduction in cytochrome c(552) and nitrate reductase (Nar) and a change in terminal oxidase activity. Cytochrome c(552) is a component of the P. aeruginosa Nar. No changes in succinate and reduced nicotinamide adenine dinucleotide dehydrogenases, ubiquinone content, Mg(2+)/Ca(2+) membrane adenosine triphosphatase, and energy coupling of electron transport to adenosine 5'-triphosphate synthesis were detected. Transport of gentamicin and dihydrostreptomycin was impaired in PAO2401, but transport of proline, arginine, glutamine, glucose or the polyamine spermidine was not reduced. Ribosomes of PAO2401, and PAO503 bound dihydrostreptomycin equally well, and cell extracts did not inactivate gentamicin or dihydrostreptomycin. Strain PAO2401 is resistant to gentamicin and dihydrostreptomycin because of impaired transport of these compounds. The transport studies indicate a selective coupling of dihydrostreptomycin and gentamicin transport with terminal electron transport. This conclusion was supported by results from another mutant (PAO417-T2) with increased Nar activity, enhanced dihydrostreptomycin and gentamicin transport and a reduction in resistance to these drugs. These results are discussed in relation to a refined model for aminoglycoside transport and briefly relative to plasmid-mediated aminoglycoside resistance.
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PMID:Aminoglycoside-resistant mutation of Pseudomonas aeruginosa defective in cytochrome c552 and nitrate reductase. 624 53

Bacteria were isolated from lake water, and their ability to remain viable in a dilute, nutrient-deficient environment was tested by a method that permits suspension of test bacteria between two appressed microporous membranes in an aqueous environment. This approach permitted separation of the lake isolates into two categories. Members of the tribe Klebsielleae were shown to have a prolonged survival rate of 40% or better after 24 h, whereas nonsurvivors were not viable for much longer than 24 h. These nonsurvivors belonged to the genera Acinetobacter, Aeromonas, Alcaligenes, Erwinia, Escherichia, Flavobacterium, and Pseudomonas. Differences in ribonuclease and adenosine triphosphatase levels between Escherichia coli (nonsurvivor) and Klebsiella (survivor) cells were detected. At pH 7.5, stressed E. coli cells contained 14% of the adenosine triphosphatase activity detected in the control, whereas at pH 5.5, in the presence of calcium ions, these same cells contained 50% of the control adenosine triphosphatase levels. At pH 7.2, E. coli cells were strongly inhibited by an adenosine triphosphatase inhibitor, bathophenanthroline (88%); oligomycin (64%); and the proton ionophore carbonyl- cyanide-m-chlorophenyl hydrazone (67%). Both sodium azide and valinomycin were only moderately inhibitory (15 and 28%, respectively). Although the ability to scavenge internal endogenous reserves seems important, we postulate that certain enteric bacteria are capable of utilizing acidic conditions (pH 5.5) as an electrochemical gradient to generate necessary high-energy intermediates for prolongation of survival beyond that possible in environments of near-neutraL pH.
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PMID:Bacterial survival in a dilute environment. 645 90

Drapeau, Gabriel R., (Macdonald College of McGill University, Quebec, Canada) and Robert A. MacLeod. Nutrition and metabolism of marine bacteria. XII. Ion activation of adenosine triphosphatase in membranes of marine bacterial cells. J. Bacteriol. 85:1413-1419. 1963.-Isolated membranes of two species of marine bacteria, a Pseudomonas and a Cytophaga, have been shown to possess adenosine triphosphatase activity. The optimal pH for enzyme action of both organisms was 8.8. The enzyme system was found to be capable of splitting inorganic o-phosphate from adenosine triphosphate (ATP), adenosine diphosphate, adenosine monophosphate, and inosine triphosphate but not from inorganic pyrophosphate. Mg(++) was required for enzyme activity; with the Pseudomonas species, the optimal Mg(++) to ATP ratio was 1:1. Ca(++) could not replace Mg(++). In the presence of the optimal concentration of Mg(++), the enzyme system was further stimulated, nonspecifically, by a number of different salts. Maximal activation was achieved at an ionic strength of 0.3 to 0.4. No evidence of an adenosine triphosphatase specifically activated by a combination of Na(+) and K(+) was obtained with either organism. No effect of ouabain on either the membrane adenosine triphosphatase activity or Na(+) transport by whole cells could be detected. The results suggest that the mechanism of ion regulation in marine bacterial cells is different from that in animal cells.
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PMID:NUTRITION AND METABOLISM OF MARINE BACTERIA. XII. ION ACTIVATION OF ADENOSINE TRIPHOSPHATASE IN MEMBRANES OF MARINE BACTERIAL CELLS. 1404 38