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rapid detection of carbapenemase-producing pseudomonas spp.a novel biochemical technique, the carba np test, has been evaluated to detect carbapenemase production in pseudomonas spp. this test was specific (100%), sensitive (94.4%), and rapid (<2 h). this cost-effective test, which could be implemented in any microbiology laboratory, offers a reliable technique for identification of carbapenemase-producing pseudomonas spp.201222972829
denitrification and environmental factors influencing nitrate removal in guaymas basin hydrothermally altered sediments.we measured potential nitrate removal and denitrification rates in hydrothermally altered sediments inhabited by beggiatoa mats and adjacent brown oil stained sediments from the guaymas basin, gulf of california. sediments with beggiatoa maintained slightly higher rates of potential denitrification than did brown sediments at 31.2 ± 12.1 versus 21.9 ± 1.4 µm n day(-1), respectively. in contrast, the nitrate removal rates in brown sediments were higher than those observed in mat-hosting sediments ...201223112796
a culture-independent approach to unravel uncultured bacteria and functional genes in a complex microbial community.most microorganisms in nature are uncultured with unknown functionality. sequence-based metagenomics alone answers 'who/what are there?' but not 'what are they doing and who is doing it and how?'. function-based metagenomics reveals gene function but is usually limited by the specificity and sensitivity of screening strategies, especially the identification of clones whose functional gene expression has no distinguishable activity or phenotypes. a 'biosensor-based genetic transducer' (bgt) techn ...201223082176
potent antibacterial antisense peptide-peptide nucleic acid conjugates against pseudomonas aeruginosa.pseudomonas aeruginosa is an opportunistic pathogen causing severe infections in hospital settings, especially with immune compromised patients, and the increasing prevalence of multidrug resistant strains urges search for new drugs with novel mechanisms of action. in this study we introduce antisense peptide-peptide nucleic acid (pna) conjugates as antibacterial agents against p. aeruginosa. we have designed and optimized antisense peptide-pna conjugates targeting the translation initiation reg ...201223030590
genome sequence of a highly efficient aerobic denitrifying bacterium, pseudomonas stutzeri t13.pseudomonas stutzeri t13 is a highly efficient aerobic denitrifying bacterium. information about the genome of this aerobic denitrifying bacterium has been limited until now. we present the draft genome of p. stutzeri t13. the results could provide further insight into the aerobic denitrification mechanism in strain t13.201223012292
fatty acid biosynthesis in pseudomonas aeruginosa is initiated by the faby class of β-ketoacyl acyl carrier protein synthases.the prototypical type ii fatty acid synthesis (fas) pathway in bacteria utilizes two distinct classes of β-ketoacyl synthase (kas) domains to assemble long-chain fatty acids, the kasiii domain for initiation and the kasi/ii domain for elongation. the central role of fas in bacterial viability and virulence has stimulated significant effort toward developing kas inhibitors, particularly against the kasiii domain of the β-acetoacetyl-acyl carrier protein (acp) synthase fabh. herein, we show that t ...201222753059
genome sequence of the broad-host-range pseudomonas phage φ-s1.the broad-host-range lytic pseudomonas phage φ-s1 possess a 40,192 bp double-stranded dna (dsdna) genome of 47 open reading frames (orfs) and belongs to the family podoviridae, subfamily autographivirinae, genus t7likevirus.201222923799
multiple transcription-activating sequences regulate the rsmz regulatory small rna of pseudomonas brassicacearum.the muts-rpos region is known to be a highly polymorphic segment of the chromosome owing to horizontal gene transfer and evolutionary processes. in pseudomonas, muts-fdxa-rsmz-rpos organization is highly conserved, as well as the promoter region of the rsmz small rna (srna)-encoding gene. one exception to this conservation is in pseudomonas brassicacearum, where a 308-nucleotide (nt) sequence, predicted to form a hairpin structure in single-stranded dna (ssdna), is inserted between the rpos and ...201222773788
membrane vesicle formation as a multiple-stress response mechanism enhances pseudomonas putida dot-t1e cell surface hydrophobicity and biofilm formation.among the adaptive responses of bacteria to rapid changes in environmental conditions, those of the cell envelope are known to be the most crucial. therefore, several mechanisms with which bacteria change their cell surface and membranes in the presence of different environmental stresses have been elucidated. among these mechanisms, the release of outer membrane vesicles (mv) in gram-negative bacteria has attracted particular research interest because of its involvement in pathogenic processes, ...201222752175
pseudomonas aeruginosa possesses two putative type i signal peptidases, lepb and pa1303, each with distinct roles in physiology and virulence.type i signal peptidases (spases) cleave signal peptides from proteins during translocation across biological membranes and hence play a vital role in cellular physiology. spase activity is also of fundamental importance to the pathogenesis of infection for many bacteria, including pseudomonas aeruginosa, which utilizes a variety of secreted virulence factors, such as proteases and toxins. p. aeruginosa possesses two noncontiguous spase homologues, lepb (pa0768) and pa1303, which share 43% amino ...201222730125
a novel 5-enolpyruvylshikimate-3-phosphate synthase shows high glyphosate tolerance in escherichia coli and tobacco plants.a key enzyme in the shikimate pathway, 5-enolpyruvylshikimate-3-phosphate synthase (epsps) is the primary target of the broad-spectrum herbicide glyphosate. identification of new aroa genes coding for epsps with a high level of glyphosate tolerance is essential for the development of glyphosate-tolerant crops. in the present study, the glyphosate tolerance of five bacterial aroa genes was evaluated in the e. coli aroa-defective strain er2799 and in transgenic tobacco plants. all five aroa genes ...201222715408
crystal structures of phosphite dehydrogenase provide insights into nicotinamide cofactor regeneration.the enzyme phosphite dehydrogenase (ptdh) catalyzes the nad(+)-dependent conversion of phosphite to phosphate and represents the first biological catalyst that has been shown to conduct the enzymatic oxidation of phosphorus. despite investigation for more than a decade into both the mechanism of its unusual reaction and its utility in cofactor regeneration, there has been a lack of any structural data for ptdh. here we present the cocrystal structure of an engineered thermostable variant of ptdh ...201222564171
first report of an extensively drug-resistant vim-2 metallo-β-lactamase-producing brevundimonas diminuta clinical isolate.in the literature, only three brevundimonas diminuta environmental isolates carrying metallo-β-lactamase genes were recently published. however, so far, no b. diminuta clinical isolates carrying these carbapenem resistance genes have been described. here we report the first vim-2 metallo-β-lactamase-producing b. diminuta clinical isolate obtained from an immunocompromised patient.201222692741
genetic diversity and ecological evaluation of fluorescent pseudomonads isolated from the leaves and roots of potato plants.a total of 828 isolates of fluorescent pseudomonads (fps) were obtained from the leaves (305 isolates) and roots (523 isolates) of potato plants grown in different geographical locations in japan, and 16s rrna gene sequences of 776 isolates were successfully determined by direct pcr sequencing. clustering analysis (≥99% identity) identified 13 and 26 operational taxonomic units (otus) for leaf- and root-associated fps, respectively, and 29 otus were identified in the phytosphere of potato plants ...201222791043
lactate utilization is regulated by the fadr-type regulator lldr in pseudomonas aeruginosa.nad-independent l-lactate dehydrogenase (l-ildh) and nad-independent d-lactate dehydrogenase (d-ildh) activities are induced coordinately by either enantiomer of lactate in pseudomonas strains. inspection of the genomic sequences of different pseudomonas strains revealed that the lldpde operon comprises 3 genes, lldp (encoding a lactate permease), lldd (encoding an l-ildh), and llde (encoding a d-ildh). cotranscription of lldp, lldd, and llde in pseudomonas aeruginosa strain xmg starts with the ...201222408166
characterization of esterase a, a pseudomonas stutzeri a15 autotransporter.autotransporters are a widespread family of proteins, generally known as virulence factors produced by gram-negative bacteria. in this study, the esterase a (esta) autotransporter of the rice root-colonizing beneficial bacterium pseudomonas stutzeri a15 was characterized. a multiple sequence alignment identified esta as belonging to clade ii of the gdsl esterase family. autologous overexpression allowed the investigation of several features of both autotransporter proteins and gdsl esterases. fi ...201222307303
pseudomonas sp. as a source of medium chain length polyhydroxyalkanoates for controlled drug delivery: perspective.controlled drug delivery technology represents one of the most rapidly advancing areas of science. they offer numerous advantages compared to conventional dosage forms including improved efficacy, reduced toxicity, improved patient compliance and convenience. over the past several decades, many delivery tools or methods were developed such as viral vector, liposome-based delivery system, polymer-based delivery system, and intelligent delivery system. recently, nonviral vectors, especially those ...201222518140
probing the applicability of autotransporter based surface display with the esta autotransporter of pseudomonas stutzeri a15.autotransporters represent a widespread family of secreted proteins in gram-negative bacteria. their seemingly easy secretion mechanism and modular structure make them interesting candidates for cell surface display of heterologous proteins. the most widely applied host organism for this purpose is escherichia coli. pseudomonas stutzeri a15 is an interesting candidate host for environmentally relevant biotechnological applications. with the recently characterized p. stutzeri a15 esta autotranspo ...201223237539
glucarpidase to combat toxic levels of methotrexate in patients.in january 2012, glucarpidase (voraxaze(®)) received approval from the us food and drug administration for intravenous treatment of toxic plasma methotrexate concentrations due to impaired renal clearance. methotrexate, an antifolate agent, has been used for over 60 years in the treatment of various cancers. high-dose methotrexate has been particularly useful in the treatment of leukemias and lymphomas. however, even with aggressive hydration and urine alkalinization, such regimens can lead to a ...201223209370
efficient production of pyruvate from dl-lactate by the lactate-utilizing strain pseudomonas stutzeri sdm.the platform chemical lactate is currently produced mainly through the fermentation of sugars presented in biomass. besides the synthesis of biodegradable polylactate, lactate is also viewed as a feedstock for the green chemistry of the future. pyruvate, another important platform chemical, can be produced from lactate through biocatalysis.201222792404
leapfrog diagnostics: demonstration of a broad spectrum pathogen identification platform in a resource-limited setting.resource-limited tropical countries are home to numerous infectious pathogens of both human and zoonotic origin. a capability for early detection to allow rapid outbreak containment and prevent spread to non-endemic regions is severely impaired by inadequate diagnostic laboratory capacity, the absence of a "cold chain" and the lack of highly trained personnel. building up detection capacity in these countries by direct replication of the systems existing in developed countries is not a feasible ...201222759725
comparative activity of carbapenem testing (the compact study) in turkey.recent evidence indicates that gram-negative bacterial pathogens, the most common of which are pseudomonas spp., enterobacteriaceae, and acinetobacter baumannii, are frequent causes of hospital-acquired infections. this study aims to evaluate the in vitro activity of doripenem and comparator carbapenem antibiotics against gram-negative clinical isolates collected from comparative activity of carbapenem testing (compact) study centres in turkey.201222340940
molecular determinants of the cofactor specificity of ribitol dehydrogenase, a short-chain dehydrogenase/reductase.ribitol dehydrogenase from zymomonas mobilis (zmrdh) catalyzes the conversion of ribitol to d-ribulose and concomitantly reduces nad(p)(+) to nad(p)h. a systematic approach involving an initial sequence alignment-based residue screening, followed by a homology model-based screening and site-directed mutagenesis of the screened residues, was used to study the molecular determinants of the cofactor specificity of zmrdh. a homologous conserved amino acid, ser156, in the substrate-binding pocket of ...201222344653
metaproteogenomic insights beyond bacterial response to naphthalene exposure and bio-stimulation.microbial metabolism in aromatic-contaminated environments has important ecological implications, and obtaining a complete understanding of this process remains a relevant goal. to understand the roles of biodiversity and aromatic-mediated genetic and metabolic rearrangements, we conducted 'omic' investigations in an anthropogenically influenced and polyaromatic hydrocarbon (pah)-contaminated soil with (nbs) or without (n) bio-stimulation with calcium ammonia nitrate, nh(4)no(3) and kh(2)po(4) a ...201222832345
metaproteogenomic insights beyond bacterial response to naphthalene exposure and bio-stimulation.microbial metabolism in aromatic-contaminated environments has important ecological implications, and obtaining a complete understanding of this process remains a relevant goal. to understand the roles of biodiversity and aromatic-mediated genetic and metabolic rearrangements, we conducted 'omic' investigations in an anthropogenically influenced and polyaromatic hydrocarbon (pah)-contaminated soil with (nbs) or without (n) bio-stimulation with calcium ammonia nitrate, nh(4)no(3) and kh(2)po(4) a ...201222832345
exposure of soil microbial communities to chromium and arsenic alters their diversity and structure.extensive use of chromium (cr) and arsenic (as) based preservatives from the leather tanning industry in pakistan has had a deleterious effect on the soils surrounding production facilities. bacteria have been shown to be an active component in the geochemical cycling of both cr and as, but it is unknown how these compounds affect microbial community composition or the prevalence and form of metal resistance. therefore, we sought to understand the effects that long-term exposure to as and cr had ...201222768219
expression of nitrous oxide reductase from pseudomonas stutzeri in transgenic tobacco roots using the root-specific rold promoter from agrobacterium rhizogenes.the nitrous oxide (n(2)o) reduction pathway from a soil bacterium, pseudomonas stutzeri, was engineered in plants to reduce n(2)o emissions. as a proof of principle, transgenic plants expressing nitrous oxide reductase (n(2)or) from p. stutzeri, encoded by the nosz gene, and other transgenic plants expressing n(2)or along with the more complete operon from p. stutzeri, encoded by nosflzdy, were generated. gene constructs were engineered under the control of a root-specific promoter and with a se ...201222423324
genome sequence of pseudomonas stutzeri sdm-lac, a typical strain for studying the molecular mechanism of lactate utilization.pseudomonas stutzeri sdm-lac is an efficient lactate utilizer with various applications in biocatalysis. here we present a 4.2-mb assembly of its genome. the annotated four adjacent genes form a lactate utilization operon, which could provide further insights into the molecular mechanism of lactate utilization.201222275095
isolation and molecular identification of landfill bacteria capable of growing on di-(2-ethylhexyl) phthalate and deteriorating pvc materials.waste materials containing di-(2-ethylhexyl) phthalate (dehp), a suspected endocrine disruptor and reasonably anticipated human carcinogen, are typically disposed of in landfills. despite this, very few studies had been conducted to isolate and identify dehp-degrading bacteria in landfill leachate. therefore, this study was conducted to isolate and characterize bacteria in landfill leachate growing on dehp as the sole carbon source and deteriorating pvc materials. four strains lhm1, lhm2, lhm3 a ...201222934997
cysteine coordination of pb(ii) is involved in the pbrr-dependent activation of the lead-resistance promoter, ppbra, from cupriavidus metallidurans ch34.the pbr resistance operon from cupriavidus metallidurans ch34 plasmid pmol30 confers resistance to pb(ii) salts, and is regulated by the pb(ii) responsive regulator pbrr, which is a merr family activator. in other metal sensing merr family regulators, such as merr, cuer, and zntr the cognate regulator binds to a promoter with an unusually long spacer between the -35 and -10 sequences, and activates transcription of resistance genes as a consequence of binding the appropriate metal. cysteine resi ...201222708803
the microbial ferrous wheel in a neutral ph groundwater seep.evidence for microbial fe redox cycling was documented in a circumneutral ph groundwater seep near bloomington, indiana. geochemical and microbiological analyses were conducted at two sites, a semi-consolidated microbial mat and a floating puffball structure. in situ voltammetric microelectrode measurements revealed steep opposing gradients of o(2) and fe(ii) at both sites, similar to other groundwater seep and sedimentary environments known to support microbial fe redox cycling. the puffball st ...201222783228
effective enhancement of pseudomonas stutzeri d-phenylglycine aminotransferase functional expression in pichia pastoris by co-expressing escherichia coli groel-groes.d-phenylglycine aminotransferase (d-phgat) of pseudomonas stutzeri st-201 catalyzes the reversible stereo-inverting transamination potentially useful in the application for synthesis of d-phenylglycine and d-4-hydroxyphenylglycine using l-glutamate as a low cost amino donor substrate in one single step. the enzyme is a relatively hydrophobic homodimeric intracellular protein difficult to express in the soluble functionally active form. over-expression of the dpga gene in e. coli resulted in the ...201222515657
engineered escherichia coli silver-binding periplasmic protein that promotes silver tolerance.silver toxicity is a problem that microorganisms face in medical and environmental settings. through exposure to silver compounds, some bacteria have adapted to growth in high concentrations of silver ions. such adapted microbes may be dangerous as pathogens but, alternatively, could be potentially useful in nanomaterial-manufacturing applications. while naturally adapted isolates typically utilize efflux pumps to achieve metal resistance, we have engineered a silver-tolerant escherichia coli st ...201222286990
extracellular dna release by undomesticated bacillus subtilis is regulated by early competence.extracellular dna (edna) release is a widespread capacity described in many microorganisms. we identified and characterized lysis-independent edna production in an undomesticated strain of bacillus subtilis. dna fragments are released during a short time in late-exponential phase. the released edna corresponds to whole genome dna, and does not harbour mutations suggesting that is not the result of error prone dna synthesis. the absence of edna was linked to a spread colony morphology, which allo ...201223133654
the influence of rhamnolipids on aliphatic fractions of diesel oil biodegradation by microorganism combinations.twelve different bacteria-yeast combinations were tested for determination of their ability to biodegrade diesel oil. the cell surface properties of the bacterial and yeast strains were correlated with the type of carbon source used in the experiments. the highest biodegradation of diesel oil after 7 days was obtained for the following combinations: aeromonas hydrophila mr4-yarrowia lipolytica eh 56 (87 %) and xantomonas maltophila mrp7-candida maltosa eh15 (90 %). degradation performances of 10 ...201224426083
the influence of rhamnolipids on aliphatic fractions of diesel oil biodegradation by microorganism combinations.twelve different bacteria-yeast combinations were tested for determination of their ability to biodegrade diesel oil. the cell surface properties of the bacterial and yeast strains were correlated with the type of carbon source used in the experiments. the highest biodegradation of diesel oil after 7 days was obtained for the following combinations: aeromonas hydrophila mr4-yarrowia lipolytica eh 56 (87 %) and xantomonas maltophila mrp7-candida maltosa eh15 (90 %). degradation performances of 10 ...201224426083
catabolism and detoxification of 1-aminoalkylphosphonic acids: n-acetylation by the phno gene product.in escherichia coli uptake and catabolism of organophosphonates are governed by the phncdefghijklmnop operon. the phno cistron is shown to encode aminoalkylphosphonate n-acetyltransferase, which utilizes acetylcoenzyme a as acetyl donor and aminomethylphosphonate, (s)- and (r)-1-aminoethylphosphonate, 2-aminoethyl- and 3-aminopropylphosphonate as acetyl acceptors. aminomethylphosphonate, (s)-1-aminoethylphosphonate, 2-aminoethyl- and 3-aminopropylphosphonate are used as phosphate source by e. co ...201223056305
genome sequences of pseudomonas luteola xldn4-9 and pseudomonas stutzeri xldn-r, two efficient carbazole-degrading strains.pseudomonas luteola xldn4-9 and pseudomonas stutzeri xldn-r are two efficient carbazole-degrading pseudomonad strains. here we present 4.63- and 4.70-mb assemblies of their genomes. their annotated key genes for carbazole catabolism are similar, which may provide further insights into the molecular mechanism of carbazole degradation in pseudomonas.201223012282
rapid detection and identification of aspergillus from lower respiratory tract specimens by use of a combined probe-high-resolution melting analysis.diagnosis of invasive aspergillosis (ia) requires increasingly rapid molecular methods that enable sensitive detection and discrimination between species. we designed and evaluated a real-time pcr-based method that combined melting temperature (t(m)) calling analysis of a specific probe with high-resolution melting analysis of the full amplicon. the test correctly identified 78 isolates of aspergillus section fumigati and non-fumigati sections of aspergillus with a limit of detection of 10(2) co ...201222837320
genome sequence of pseudomonas stutzeri strain jm300 (dsm 10701), a soil isolate and model organism for natural transformation.pseudomonas stutzeri strain jm300 (dsm 10701) is a denitrifying soil isolate and a model organism for natural transformation in bacteria. here we report the first complete genome sequence of jm300, the reference strain of genomovar 8 for the species.201222965097
production of copolyesters of 3-hydroxybutyrate and medium-chain-length 3-hydroxyalkanoates by e. coli containing an optimized pha synthase gene.microbial polyhydroxyalkanoates (pha) are biopolyesters consisting of diverse monomers. pha synthase phac2ps cloned from pseudomonas stutzeri 1317 is able to polymerize short-chain-length (scl) 3-hydroxybutyrate (3hb) monomers and medium-chain-length (mcl) 3-hydroxyalkanoates (3ha) with carbon chain lengths ranging from c6 to c12. however, the scl and mcl pha production in escherichia coli expressing phac2ps is limited with very low pha yield.201222978778
natural transformation facilitates transfer of transposons, integrons and gene cassettes between bacterial species.we have investigated to what extent natural transformation acting on free dna substrates can facilitate transfer of mobile elements including transposons, integrons and/or gene cassettes between bacterial species. naturally transformable cells of acinetobacter baylyi were exposed to dna from integron-carrying strains of the genera acinetobacter, citrobacter, enterobacter, escherichia, pseudomonas, and salmonella to determine the nature and frequency of transfer. exposure to the various dna sourc ...201222876180
genome sequence of the moderately halotolerant, arsenite-oxidizing bacterium pseudomonas stutzeri ts44.we present the draft genome sequence of pseudomonas stutzeri ts44, a moderately halotolerant, arsenite-oxidizing bacterium isolated from arsenic-contaminated soil. the genome contains genes for arsenite oxidation, arsenic resistance, and ectoine/hydroxyectoine biosynthesis. the genome information will be useful for exploring adaptation of p. stutzeri ts44 to an arsenic-contaminated environment.201222843599
metallo-β-lactamase structure and function.β-lactam antibiotics are the most commonly used antibacterial agents and growing resistance to these drugs is a concern. metallo-β-lactamases are a diverse set of enzymes that catalyze the hydrolysis of a broad range of β-lactam drugs including carbapenems. this diversity is reflected in the observation that the enzyme mechanisms differ based on whether one or two zincs are bound in the active site that, in turn, is dependent on the subclass of β-lactamase. the dissemination of the genes encodin ...201223163348
metallo-β-lactamase structure and function.β-lactam antibiotics are the most commonly used antibacterial agents and growing resistance to these drugs is a concern. metallo-β-lactamases are a diverse set of enzymes that catalyze the hydrolysis of a broad range of β-lactam drugs including carbapenems. this diversity is reflected in the observation that the enzyme mechanisms differ based on whether one or two zincs are bound in the active site that, in turn, is dependent on the subclass of β-lactamase. the dissemination of the genes encodin ...201223163348
central line-associated bloodstream infections in adult hematology patients with febrile neutropenia: an evaluation of surveillance definitions using differential time to blood culture positivity.we used differential time to positivity between central and peripheral blood cultures to evaluate the positive predictive value (ppv) of the national healthcare safety network central line-associated bloodstream infection (clabsi) surveillance definition among hematology patients with febrile neutropenia. the ppv was 27.7%, which suggests that, when the definition is applied to this population, clabsi rates will be substantially overestimated.201223221198
central line-associated bloodstream infections in adult hematology patients with febrile neutropenia: an evaluation of surveillance definitions using differential time to blood culture positivity.we used differential time to positivity between central and peripheral blood cultures to evaluate the positive predictive value (ppv) of the national healthcare safety network central line-associated bloodstream infection (clabsi) surveillance definition among hematology patients with febrile neutropenia. the ppv was 27.7%, which suggests that, when the definition is applied to this population, clabsi rates will be substantially overestimated.201223221198
rationally re-designed mutation of nad-independent l-lactate dehydrogenase: high optical resolution of racemic mandelic acid by the engineered escherichia coli.nad-independent l-lactate dehydrogenase (l-ildh) from pseudomonas stutzeri sdm can potentially be used for the kinetic resolution of small aliphatic 2-hydroxycarboxylic acids. however, this enzyme showed rather low activity towards aromatic 2-hydroxycarboxylic acids.201223176608
investigation of the role of arg301 identified in the x-ray structure of phosphite dehydrogenase.phosphite dehydrogenase (ptdh) from pseudomonas stutzeri catalyzes the nicotinamide adenine dinucleotide-dependent oxidation of phosphite to phosphate. the enzyme belongs to the family of d-hydroxy acid dehydrogenases (dhdhs). a search of the protein databases uncovered many additional putative phosphite dehydrogenases. the genes encoding four diverse candidates were cloned and expressed, and the enzymes were purified and characterized. all oxidized phosphite to phosphate and had similar kinetic ...201222564138
nad-independent l-lactate dehydrogenase is required for l-lactate utilization in pseudomonas stutzeri sdm.various pseudomonas strains can use l-lactate as their sole carbon source for growth. however, the l-lactate-utilizing enzymes in pseudomonas have never been identified and further studied.201222574176
a designed functional metalloenzyme that reduces o2 to h2o with over one thousand turnovers. 201222539151
use of structural phylogenetic networks for classification of the ferritin-like superfamily.in the postgenomic era, bioinformatic analysis of sequence similarity is an immensely powerful tool to gain insight into evolution and protein function. over long evolutionary distances, however, sequence-based methods fail as the similarities become too low for phylogenetic analysis. macromolecular structure generally appears better conserved than sequence, but clear models for how structure evolves over time are lacking. the exponential growth of three-dimensional structural information may al ...201222535960
complete genome sequence of the naphthalene-degrading bacterium pseudomonas stutzeri an10 (ccug 29243).pseudomonas stutzeri an10 (ccug 29243) can be considered a model strain for aerobic naphthalene degradation. we report the complete genome sequence of this bacterium. its 4.71-mb chromosome provides insights into other biodegradative capabilities of strain an10 (i.e., benzoate catabolism) and suggests a high number of horizontal gene transfer events.201223144395
the rnf complex of clostridium ljungdahlii is a proton-translocating ferredoxin:nad+ oxidoreductase essential for autotrophic growth.it has been predicted that the rnf complex of clostridium ljungdahlii is a proton-translocating ferredoxin:nad(+) oxidoreductase which contributes to atp synthesis by an h(+)-translocating atpase under both autotrophic and heterotrophic growth conditions. the recent development of methods for genetic manipulation of c. ljungdahlii made it possible to evaluate the possible role of the rnf complex in energy conservation. disruption of the c. ljungdahlii rnf operon inhibited autotrophic growth. atp ...201223269825
iridescence of a marine bacterium and classification of prokaryotic structural colors.iridescence is a property of structural color that is occasionally encountered in higher eukaryotes but that has been poorly documented in the prokaryotic kingdom. in the present work, we describe a marine bacterium, identified as cellulophaga lytica, isolated from the surface of an anemone, that exhibits bright green iridescent colonies under direct epi-illumination. this phenomenon has not previously been investigated in detail. in this study, color changes of c. lytica colonies were observed ...201222267664
differential isotopic fractionation during cr(vi) reduction by an aquifer-derived bacterium under aerobic versus denitrifying conditions.we studied cr isotopic fractionation during cr(vi) reduction by pseudomonas stutzeri strain rch2. despite the fact that strain rch2 reduces cr(vi) cometabolically under both aerobic and denitrifying conditions and at similar specific rates, fractionation was markedly different under these two conditions (ε was ∼2‰ aerobically and ∼0.4‰ under denitrifying conditions).201222286991
investigation of antimicrobial activity and statistical optimization of bacillus subtilis spb1 biosurfactant production in solid-state fermentation.during the last years, several applications of biosurfactants with medical purposes have been reported. biosurfactants are considered relevant molecules for applications in combating many diseases. however, their use is currently extremely limited due to their high cost in relation to that of chemical surfactants. use of inexpensive substrates can drastically decrease its production cost. here, twelve solid substrates were screened for the production of bacillus subtilis spb1 biosurfactant and t ...201222536017
the rnf complex of clostridium ljungdahlii is a proton-translocating ferredoxin:nad+ oxidoreductase essential for autotrophic growth.it has been predicted that the rnf complex of clostridium ljungdahlii is a proton-translocating ferredoxin:nad(+) oxidoreductase which contributes to atp synthesis by an h(+)-translocating atpase under both autotrophic and heterotrophic growth conditions. the recent development of methods for genetic manipulation of c. ljungdahlii made it possible to evaluate the possible role of the rnf complex in energy conservation. disruption of the c. ljungdahlii rnf operon inhibited autotrophic growth. atp ...201223269825
evaluation of the bruker biotyper and vitek ms matrix-assisted laser desorption ionization-time of flight mass spectrometry systems for identification of nonfermenting gram-negative bacilli isolated from cultures from cystic fibrosis patients.the bruker biotyper and vitek ms matrix-assisted laser desorption ionization-time of flight (maldi-tof) mass spectrometry (ms) instruments were evaluated for the identification of nonfermenting gram-negative bacilli (nfgnb) by a blinded comparison to conventional biochemical or molecular methods. two hundred nfgnb that were recovered from cultures from cystic fibrosis patients in the university of iowa health care (uihc) microbiology laboratory between 1 january 2006 and 31 october 2010 were sen ...201222495566
reciprocal tripartite interactions between the aedes aegypti midgut microbiota, innate immune system and dengue virus influences vector competence.dengue virus is one of the most important arboviral pathogens and the causative agent of dengue fever, dengue hemorrhagic fever, and dengue shock syndrome. it is transmitted between humans by the mosquitoes aedes aegypti and aedes albopictus, and at least 2.5 billion people are at daily risk of infection. during their lifecycle, mosquitoes are exposed to a variety of microbes, some of which are needed for their successful development into adulthood. however, recent studies have suggested that th ...201222413032
fatal case of brucellosis misdiagnosed in early stages of brucella suis infection in a 46-year-old patient with marfan syndrome.we report a fatal case of brucella suis endocarditis initially misdiagnosed by automated identification systems as ochrobactrum anthropi infection in a patient with a history of marfan syndrome and recreational feral swine hunting. this report emphasizes the need to consider brucellosis as a part of the differential diagnosis of acute febrile illness, particularly in patients with known risk of exposure.201222495564
the twin-arginine translocation pathway in α-proteobacteria is functionally preserved irrespective of genomic and regulatory divergence.the twin-arginine translocation (tat) pathway exports fully folded proteins out of the cytoplasm of gram-negative and gram-positive bacteria. although much progress has been made in unraveling the molecular mechanism and biochemical characterization of the tat system, little is known concerning its functionality and biological role to confer adaptive skills, symbiosis or pathogenesis in the α-proteobacteria class. a comparative genomic analysis in the α-proteobacteria class confirmed the presenc ...201222438962
structural and functional insights from the metagenome of an acidic hot spring microbial planktonic community in the colombian andes.a taxonomic and annotated functional description of microbial life was deduced from 53 mb of metagenomic sequence retrieved from a planktonic fraction of the neotropical high andean (3,973 meters above sea level) acidic hot spring el coquito (ec). a classification of unassembled metagenomic reads using different databases showed a high proportion of gammaproteobacteria and alphaproteobacteria (in total read affiliation), and through taxonomic affiliation of 16s rrna gene fragments we observed th ...201223251687
characterization of bacteria in ballast water using maldi-tof mass spectrometry.to evaluate a rapid and cost-effective method for monitoring bacteria in ballast water, several marine bacterial isolates were characterized by matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms). since international maritime organization (imo) regulations are concerned with the unintended transportation of pathogenic bacteria through ballast water, emphasis was placed on detecting species of vibrio, enterococci and coliforms. seawater samples collected fr ...201222685576
functional importance of a pair of conserved glutamic acid residues and of ca(2+) binding in the cbb(3)-type oxygen reductases from rhodobacter sphaeroides and vibrio cholerae.the cbb(3)-type cytochrome c oxidases are members of the family of heme-copper proton pumping respiratory oxygen reductases. the structure of the cbb(3)-type oxidase from pseudomonas stutzeri reveals that, in addition to the six redox-active metal centers (two b-type hemes, three c-type hemes, and cu(b)), the enzyme also contains at least one ca(2+). the calcium bridges two propionate carboxyls at the interface between the low-spin heme b and the active-site heme b(3) and, in addition, is ligate ...201222913716
the periplasmic nitrate reductase nap is required for anaerobic growth and involved in redox control of magnetite biomineralization in magnetospirillum gryphiswaldense.the magnetosomes of many magnetotactic bacteria consist of membrane-enveloped magnetite crystals, whose synthesis is favored by a low redox potential. however, the cellular redox processes governing the biomineralization of the mixed-valence iron oxide have remained unknown. here, we show that in the alphaproteobacterium magnetospirillum gryphiswaldense, magnetite biomineralization is linked to dissimilatory nitrate reduction. a complete denitrification pathway, including gene functions for nitr ...201222730130
biochemical characterization of the purple form of marinobacter hydrocarbonoclasticus nitrous oxide reductase.nitrous oxide reductase (n(2)or) catalyses the final step of the denitrification pathway-the reduction of nitrous oxide to nitrogen. the catalytic centre (cuz) is a unique tetranuclear copper centre bridged by inorganic sulphur in a tetrahedron arrangement that can have different oxidation states. previously, marinobacter hydrocarbonoclasticus n(2)or was isolated with the cuz centre as cuz*, in the [1cu(2+) : 3cu(+)] redox state, which is redox inert and requires prolonged incubation under reduc ...201222451106
structural basis for nitrous oxide generation by bacterial nitric oxide reductases.the crystal structure of the bacterial nitric oxide reductase (cnor) from pseudomonas aeruginosa is reported. its overall structure is similar to those of the main subunit of aerobic and micro-aerobic cytochrome oxidases (coxs), in agreement with the hypothesis that all these enzymes are members of the haem-copper oxidase superfamily. however, substantial structural differences between cnor and cox are observed in the catalytic centre and the delivery pathway of the catalytic protons, which shou ...201222451105
nitrous oxide production and consumption: regulation of gene expression by gas-sensitive transcription factors.several biochemical mechanisms contribute to the biological generation of nitrous oxide (n(2)o). n(2)o generating enzymes include the respiratory nitric oxide (no) reductase, an enzyme from the flavo-diiron family, and flavohaemoglobin. on the other hand, there is only one enzyme that is known to use n(2)o as a substrate, which is the respiratory n(2)o reductase typically found in bacteria capable of denitrification (the respiratory reduction of nitrate and nitrite to dinitrogen). this article w ...201222451107
the diheme cytochrome c peroxidase from shewanella oneidensis requires reductive activation.we report the characterization of the diheme cytochrome c peroxidase (ccp) from shewanella oneidensis (so) using uv-visible absorbance, electron paramagnetic resonance spectroscopy, and michaelis-menten kinetics. while sequence alignment with other bacterial diheme cytochrome c peroxidases suggests that so ccp may be active in the as-isolated state, we find that so ccp requires reductive activation for full activity, similar to the case for the canonical pseudomonas type of bacterial ccp enzyme. ...201222239664
infectious etiologies of acute febrile illness among patients seeking health care in south-central cambodia.the agents of human febrile illness can vary by region and country suggesting that diagnosis, treatment, and control programs need to be based on a methodical evaluation of area-specific etiologies. from december 2006 to december 2009, 9,997 individuals presenting with acute febrile illness at nine health care clinics in south-central cambodia were enrolled in a study to elucidate the etiologies. upon enrollment, respiratory specimens, whole blood, and serum were collected. testing was performed ...201222302857
rapid discrimination of salmonella enterica serovar typhi from other serovars by maldi-tof mass spectrometry.systemic infections caused by salmonella enterica are an ongoing public health problem especially in sub-saharan africa. essentially typhoid fever is associated with high mortality particularly because of the increasing prevalence of multidrug-resistant strains. thus, a rapid blood-culture based bacterial species diagnosis including an immediate sub-differentiation of the various serovars is mandatory. at present, maldi-tof based intact cell mass spectrometry (icms) advances to a widely used rou ...201222768195
defining falciparum-malaria-attributable severe febrile illness in moderate-to-high transmission settings on the basis of plasma pfhrp2 concentration.in malaria-endemic settings, asymptomatic parasitemia complicates the diagnosis of malaria. histidine-rich protein 2 (hrp2) is produced by plasmodium falciparum, and its plasma concentration reflects the total body parasite burden. we aimed to define the malaria-attributable fraction of severe febrile illness, using the distributions of plasma p. falciparum hrp2 (pfhrp2) concentrations from parasitemic children with different clinical presentations.201223136222
defining falciparum-malaria-attributable severe febrile illness in moderate-to-high transmission settings on the basis of plasma pfhrp2 concentration.in malaria-endemic settings, asymptomatic parasitemia complicates the diagnosis of malaria. histidine-rich protein 2 (hrp2) is produced by plasmodium falciparum, and its plasma concentration reflects the total body parasite burden. we aimed to define the malaria-attributable fraction of severe febrile illness, using the distributions of plasma p. falciparum hrp2 (pfhrp2) concentrations from parasitemic children with different clinical presentations.201223136222
multidrug-resistance and toxic metal tolerance of medically important bacteria isolated from an aquaculture system.the use of antimicrobials and toxic metals should be considered carefully in aquaculture and surrounding environments. we aimed to evaluate medically relevant bacteria in an aquaculture system and their susceptibility to antimicrobials and toxic metals. selective cultures for enterobacteria (ent), non-fermenting gram-negative rods (nfr) and gram-positive cocci (gpc) were obtained from water samples collected in two different year seasons. the isolated bacteria were biochemically identified and a ...201222972388
bacterial contamination of dental unit waterlines.safety of patients and dental personnel requires the appropriate microbiological water quality in dental units. during treatment, patients and dental workers are exposed both to direct contact with bacteria-contaminated water in the form of splatter and with contaminated water aerosol emitted during work by unit handpieces, including rotating and ultrasonic instruments. the aim of the study was to determine the qualitative and quantitative contamination of water in dental unit reservoirs with ae ...201222899458
bacterial contamination of dental unit waterlines.safety of patients and dental personnel requires the appropriate microbiological water quality in dental units. during treatment, patients and dental workers are exposed both to direct contact with bacteria-contaminated water in the form of splatter and with contaminated water aerosol emitted during work by unit handpieces, including rotating and ultrasonic instruments. the aim of the study was to determine the qualitative and quantitative contamination of water in dental unit reservoirs with ae ...201222899458
complete sequence of a novel 178-kilobase plasmid carrying bla(ndm-1) in a providencia stuartii strain isolated in afghanistan.in response to global concerns over the spread of the new delhi metallo-β-lactamase gene 1, bla(ndm-1), a monthly surveillance program was initiated in september 2010. all carbapenem-resistant gram-negative strains forwarded to our facility are screened for this gene. to date, 321 carbapenem-resistant isolates, encompassing 11 bacterial species, have been tested. in february 2011, two strains of providencia stuartii, submitted from a military hospital in afghanistan, tested positive for bla(ndm- ...201222290972
role of trehalose in salinity and temperature tolerance in the model halophilic bacterium chromohalobacter salexigens.the disaccharide trehalose is considered as a universal stress molecule, protecting cells and biomolecules from injuries imposed by high osmolarity, heat, oxidation, desiccation and freezing. chromohalobacter salexigens is a halophilic and extremely halotolerant γ-proteobacterium of the family halomonadaceae. in this work, we have investigated the role of trehalose as a protectant against salinity, temperature and desiccation in c. salexigens. a mutant deficient in the trehalose-6-phosphate synt ...201222448254
biological sources and sinks of nitrous oxide and strategies to mitigate emissions.nitrous oxide (n(2)o) is a powerful atmospheric greenhouse gas and cause of ozone layer depletion. global emissions continue to rise. more than two-thirds of these emissions arise from bacterial and fungal denitrification and nitrification processes in soils, largely as a result of the application of nitrogenous fertilizers. this article summarizes the outcomes of an interdisciplinary meeting, 'nitrous oxide (n(2)o) the forgotten greenhouse gas', held at the kavli royal society international cen ...201222451101
structural determinants of the β-selectivity of a bacterial aminotransferase.chiral β-amino acids occur as constituents of various natural and synthetic compounds with potentially useful bioactivities. the pyridoxal 5'-phosphate (plp)-dependent s-selective transaminase from mesorhizobium sp. strain luk (mesat) is a fold type i aminotransferase that can be used for the preparation of enantiopure β-phe and derivatives thereof. using x-ray crystallography, we solved structures of mesat in complex with (s)-β-phe, (r)-3-amino-5-methylhexanoic acid, 2-oxoglutarate, and the inh ...201222745123
nitric oxide and nitrous oxide turnover in natural and engineered microbial communities: biological pathways, chemical reactions, and novel technologies.nitrous oxide (n(2)o) is an environmentally important atmospheric trace gas because it is an effective greenhouse gas and it leads to ozone depletion through photo-chemical nitric oxide (no) production in the stratosphere. mitigating its steady increase in atmospheric concentration requires an understanding of the mechanisms that lead to its formation in natural and engineered microbial communities. n(2)o is formed biologically from the oxidation of hydroxylamine (nh(2)oh) or the reduction of ni ...201223109930
impact of quaternary structure upon bacterial cytochrome c peroxidases: does homodimerization matter?all known active forms of diheme bacterial cytochrome c peroxidase (bccp) enzymes are described by a homodimeric state. further, the majority of bccps reported display activity only when the high-potential electron transfer heme of the protein (fe(h)) is reduced to the ferrous oxidation state. reduction of fe(h) results in a set of conformational changes allowing for the low-potential peroxidatic heme (fe(l)) to adopt a high-spin, five-coordinate state that is capable of binding substrate. here ...201223189923
altered large-ring cyclodextrin product profile due to a mutation at tyr-172 in the amylomaltase of corynebacterium glutamicum.corynebacterium glutamicum amylomaltase (cgam) catalyzes the formation of large-ring cyclodextrins (lr-cds) with a degree of polymerization of 19 and higher. the cloned cgam gene was ligated into the pet-17b vector and used to transform escherichia coli bl21(de3). site-directed mutagenesis of tyr-172 in cgam to alanine (y172a) was performed to determine its role in the control of lr-cd production. both the recombinant wild-type (wt) and y172a enzymes were purified to apparent homogeneity and cha ...201222865069
exploring the proton pump and exit pathway for pumped protons in cytochrome ba3 from thermus thermophilus.the heme-copper oxygen reductases are redox-driven proton pumps. in the current work, the effects of mutations in a proposed exit pathway for pumped protons are examined in the ba(3)-type oxygen reductase from thermus thermophilus, leading from the propionates of heme a(3) to the interface between subunits i and ii. recent studies have proposed important roles for his376 and asp372, both of which are hydrogen-bonded to propionate-a of heme a(3), and for glu126(ii) (subunit ii), which is hydrogen ...201222431640
trace metal requirements for microbial enzymes involved in the production and consumption of methane and nitrous oxide.fluxes of greenhouse gases to the atmosphere are heavily influenced by microbiological activity. microbial enzymes involved in the production and consumption of greenhouse gases often contain metal cofactors. while extensive research has examined the influence of fe bioavailability on microbial co(2) cycling, fewer studies have explored metal requirements for microbial production and consumption of the second- and third-most abundant greenhouse gases, methane (ch(4)), and nitrous oxide (n(2)o). ...201222363333
proteogenomic elucidation of the initial steps in the benzene degradation pathway of a novel halophile, arhodomonas sp. strain rozel, isolated from a hypersaline environment.lately, there has been a special interest in understanding the role of halophilic and halotolerant organisms for their ability to degrade hydrocarbons. the focus of this study was to investigate the genes and enzymes involved in the initial steps of the benzene degradation pathway in halophiles. the extremely halophilic bacteria arhodomonas sp. strain seminole and arhodomonas sp. strain rozel, which degrade benzene and toluene as the sole carbon source at high salinity (0.5 to 4 m nacl), were is ...201222885747
characterization of a novel phenol hydroxylase in indoles biotransformation from a strain arthrobacter sp. w1 [corrected].indigoids, as popular dyes, can be produced by microbial strains or enzymes catalysis. however, the new valuable products with their transformation mechanisms, especially inter-conversion among the intermediates and products have not been clearly identified yet. therefore, it is necessary to investigate novel microbial catalytic processes for indigoids production systematically.201223028517
identification of bacteria utilizing biphenyl, benzoate, and naphthalene in long-term contaminated soil.bacteria were identified associated with biodegradation of aromatic pollutants biphenyl, benzoate, and naphthalene in a long-term polychlorinated biphenyl- and polyaromatic hydrocarbon-contaminated soil. in order to avoid biases of culture-based approaches, stable isotope probing was applied in combination with sequence analysis of 16 s rrna gene pyrotags amplified from (13)c-enriched dna fractions. special attention was paid to pyrosequencing data analysis in order to eliminate the errors cause ...201222808223
diversity of 5s rrna genes within individual prokaryotic genomes.we examined intragenomic variation of paralogous 5s rrna genes to evaluate the concept of ribosomal constraints. in a dataset containing 1161 genomes from 779 unique species, 96 species exhibited > 3% diversity. twenty-seven species with > 10% diversity contained a total of 421 mismatches between all pairs of the most dissimilar copies of 5s rrna genes. the large majority (401 of 421) of the diversified positions were conserved at the secondary structure level. the high diversity was associated ...201222765222
unexpected nondenitrifier nitrous oxide reductase gene diversity and abundance in soils.agricultural and industrial practices more than doubled the intrinsic rate of terrestrial n fixation over the past century with drastic consequences, including increased atmospheric nitrous oxide (n(2)o) concentrations. n(2)o is a potent greenhouse gas and contributor to ozone layer destruction, and its release from fixed n is almost entirely controlled by microbial activities. mitigation of n(2)o emissions to the atmosphere has been attributed exclusively to denitrifiers possessing nosz, the en ...201223150571
effective selenium volatilization under aerobic conditions and recovery from the aqueous phase by pseudomonas stutzeri nt-i.selenium is an important rare metal and its recovery from waste and wastewater is necessary for its sustainable utilization. microbial selenium volatilization is suitable for selenium recovery from industrial wastewater because volatile selenium can be recovered in recyclable forms free from other chemicals. we found that pseudomonas stutzeri nt-i can aerobically transform selenate, selenite, and biogenic elemental selenium into dimethyldiselenide as well as dimethylselenide; these were temporar ...201223270669
hepatic portal venous gas--three non-fatal cases and review of the literature.hepatic portal venous gas is a rare imaging finding most commonly associated with intestinal ischaemia and high mortality. increased use of advanced imaging techniques has resulted in increased reporting and recognition of hepatic portal venous gas. advanced imaging can also recognise the many associated pathologies which have variable management strategies and prognoses.201223526850
hcpr of porphyromonas gingivalis is required for growth under nitrosative stress and survival within host cells.although the gram-negative, anaerobic periodontopathogen porphyromonas gingivalis must withstand nitrosative stress, which is particularly high in the oral cavity, the mechanisms allowing for protection against such stress are not known in this organism. in this study, microarray analysis of p. gingivalis transcriptional response to nitrite and nitric oxide showed drastic upregulation of the pg0893 gene coding for hybrid cluster protein (hcp), which is a putative hydroxylamine reductase. althoug ...201222778102
ethanolamine utilization in vibrio alginolyticus.ethanolamine is used as an energy source by phylogenetically diverse bacteria including pathogens, by the concerted action of proteins from the eut-operon. previous studies have revealed the presence of eutbc genes encoding ethanolamine-ammonia lyase, a key enzyme that breaks ethanolamine into acetaldehyde and ammonia, in about 100 bacterial genomes including members of gamma-proteobacteria. however, ethanolamine utilization has not been reported for any member of the vibrio genus. our comparati ...201223234435
type iv pilin proteins: versatile molecular modules.type iv pili (t4p) are multifunctional protein fibers produced on the surfaces of a wide variety of bacteria and archaea. the major subunit of t4p is the type iv pilin, and structurally related proteins are found as components of the type ii secretion (t2s) system, where they are called pseudopilins; of dna uptake/competence systems in both gram-negative and gram-positive species; and of flagella, pili, and sugar-binding systems in the archaea. this broad distribution of a single protein family ...201223204365
effects of resource chemistry on the composition and function of stream hyporheic biofilms.fluvial ecosystems process large quantities of dissolved organic matter as it moves from the headwater streams to the sea. in particular, hyporheic sediments are centers of high biogeochemical reactivity due to their elevated residence time and high microbial biomass and activity. however, the interaction between organic matter and microbial dynamics in the hyporheic zone remains poorly understood. we evaluated how variance in resource chemistry affected the microbial community and its associate ...201222347877
respiratory viruses from hospitalized children with severe pneumonia in the philippines.pneumonia remains a leading cause of child death in developing countries. the viruses in severe pneumonia remain poorly defined.201223092190
diversity and antibiograms of bacterial organisms isolated from samples of household drinking-water consumed by hiv-positive individuals in rural settings, south africa.diarrhoea is a hallmark of hiv infections in developing countries, and many diarrhoea-causing agents are often transmitted through water. the objective of the study was to determine the diversity and antibiotic susceptibility profiles of bacterial organisms isolated from samples of household drinking-water consumed by hiv-infected and aids patients. in the present study, household water stored for use by hiv-positive patients was tested for microbial quality, and isolated bacterial organisms wer ...201223082625
Effect of carbon source, C/N ratio, nitrate and dissolved oxygen concentration on nitrite and ammonium production from denitrification process by Pseudomonasstutzeri D6.Pseudomonasstutzeri D6, selectively isolated from activated sludge was used to study NO(2)(-) and NH(4)(+) production from denitrification processes. Changes in carbon type, C/N ratio and oxygen concentration significantly influenced the magnitude of NO(2)(-) and NH(4)(+) accumulation through denitrification. D6 showed a preference for citrate and acetate, which led to the largest quantity of nitrate reduced and which were exhausted most rapidly, with minimal intermediate products accumulation. ...201222074905
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