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occurrence and ecological risk assessment of fluoroquinolone antibiotics in hospital waste of lahore, pakistan.in the present study, wastewater and sludge samples of two major hospitals of lahore, pakistan were analyzed by developing an hplc-uv method for the possible occurrence of five frequently used fluoroquinolone antibiotics i.e. ofloxacin, ciprofloxacin, sparfloxacin, moxifloxacin and gemifloxacin. the highest detected concentration was for moxifloxacin in both wastewater (224 μg/l) and sludge samples (219 μg/kg. the highest concentration of ofloxacin, ciprofloxacin, sparfloxacin and gemifloxacin w ...201626773357
toxicity of titanium dioxide nanoparticles on pseudomonas putida.the increasing use of engineered nanoparticles (nps) in industrial and household applications will very likely lead to the release of such materials into the environment. as wastewater treatment plants (wwtps) are usually the last barrier before the water is discharged into the environment, it is important to understand the effects of these materials in the biotreatment processes, since the results in the literature are usually contradictory. we proposed the use of flow cytometry (fc) technology ...201626771160
effects of carbazole-degradative plasmid pcar1 on biofilm morphology in pseudomonas putida kt2440.bacteria typically form biofilms under natural conditions. to elucidate the effect of the carriage of carbazole-degradative plasmid pcar1 on biofilm formation by host bacteria, we compared the biofilm morphology, using confocal laser scanning microscopy, of three pcar1-free and pcar1-carrying pseudomonas hosts: p. putida kt2440, p. aeruginosa pao1 and p. fluorescens pf0-1. although pcar1 did not significantly affect biofilm formation by pao1 or pf0-1, pcar1-carrying kt2440 became filamentous and ...201626743211
pseudomonas putida stimulates primordia on agaricus bitorquis.casing layer is one step of agaricus bisporus cultivation where there is a competitive environment with a high number of microorganisms and diversity interacting with mycelia. it is suggested that a minimal community of these microorganisms would be necessary to stimulate fructification. however, a. bisporus is not able to produce primordia in sterile casing layers or petri dishes. thus, the objective of this study was to characterize bacterial microbiota of casing layers from a. bisporus cultiv ...201626742772
transport, retention, and long-term release behavior of zno nanoparticle aggregates in saturated quartz sand: role of solution ph and biofilm coating.the transport, retention, and long-term release of zinc oxide nanoparticle aggregates (denoted below as zno-nps) were investigated in saturated, bare and biofilm (pseudomonas putida) coated sand packed columns. almost complete retention of zno-nps occurred in bare and biofilm coated sand when the influent solution ph was 9 and the ionic strength (is) was 0.1 or 10 mm nacl, and the retention profiles were always hyper-exponential. increasing the solution is and biofilm coating produced enhanced r ...201626741396
a novel application of paracoccus pantotrophus for the decolorization of melanoidins from distillery effluent under static conditions.melanoidin is the hazardous byproduct formed during the production of ethanol in distilleries. in the present study, a highly effective melanoidin decolorizing bacterial isolate, sag1, was isolated from the effluent enriched soil of a distillery. this strain, identified as paracoccus pantotrophus, was highly efficient to decolorize melanoidins up to 81.2 ± 2.43% in the presence of glucose and nh4no3. the effects of autoclaved as well as living cells and inoculums size on decolorization activity ...201626724506
beta-ketoadipic acid and muconolactone production from a lignin-related aromatic compound through the protocatechuate 3,4-metabolic pathway.in this work, the effects of pcaj (beta-ketoadipate:succinyl-coenzyme a transferase)- and pcad (beta-ketoadipate enol-lactone hydrolase)-inactivation on protocatechuic acid metabolism in pseudomonas putida kt2440 were evaluated. beta-ketoadipic acid was produced from protocatechuic acid by the inactivation of pcaj as expected; however, a portion of the produced beta-ketoadipic acid was converted to levulinic acid through a purification step consisting of extraction from the culture and recrystal ...201626723258
fed-batch production of poly-3-hydroxydecanoate from decanoic acid.decanoic acid is an ideal substrate for the synthesis of medium-chain-length poly-3-hydroxyalkanoate (mcl-pha), but its use for this purpose has only previously been studied in shake-flasks likely due to its surfactant properties, low aqueous solubility and high melting temperature. a fed-batch fermentation process was developed for the production of mcl-pha from decanoic acid using pseudomonas putida kt2440. decanoic acid was kept in liquid form by heating or by mixing with acetic acid to preve ...201626689481
genetic characterization of a novel bladim-2-carrying megaplasmid p12969-dim from clinical pseudomonas putida.to characterize a bladim-2-carrying 409 kb megaplasmid p12969-dim of pseudomonas putida 12969 from a patient with pneumonia in china.201626679251
enhanced retention of chemotactic bacteria in a pore network with residual napl contamination.nonaqueous-phase liquid (napl) contaminants are difficult to eliminate from natural aquifers due, in part, to the heterogeneous structure of the soil. chemotaxis enhances the mixing of bacteria with contaminant sources in low-permeability regions, which may not be readily accessible by advection and dispersion alone. a microfluidic device was designed to mimic heterogeneous features of a contaminated groundwater aquifer. napl droplets (toluene) were trapped within a fine pore network, and bacter ...201626633578
the catalytic mechanism of decarboxylative hydroxylation of salicylate hydroxylase revealed by crystal structure analysis at 2.5 å resolution.the x-ray crystal structure of a salicylate hydroxylase from pseudomonas putida s-1 complexed with coenzyme fad has been determined to a resolution of 2.5 å. structural conservation with p- or m-hydroxybenzoate hydroxylase is very good throughout the topology, despite a low amino sequence identity of 20-40% between these three hydroxylases. salicylate hydroxylase is composed of three distinct domains and includes fad between domains i and ii, which is accessible to solvent. in this study, which ...201626616054
environmental stress speeds up dna replication in pseudomonas putida in chemostat cultivations.cellular response to different types of stress is the hallmark of the cell's strategy for survival. how organisms adjust their cell cycle dynamics to compensate for changes in environmental conditions is an important unanswered question in bacterial physiology. a cell using binary fission for reproduction passes through three stages during its cell cycle: a stage from cell birth to initiation of replication, a dna replication phase and a period of cell division. we present a detailed analysis of ...201626299279
μmore: a microfluidic magnetic oscillation reactor for accelerated parameter optimization in biocatalysis.enzymatic parameter determination is an essential step in biocatalytic process development. therefore higher throughput in miniaturized devices is urgently needed. an ideal microfluidic device should combine easy immobilization and retention of a minimal amount of biocatalyst with a well-mixed reaction volume. together, all criteria are hardly met by current tools. here we describe a microfluidic reactor (μmore) which employs magnetic particles for both enzyme immobilization and efficient mixing ...201627288595
total growth and root-cluster production by legumes and proteas depends on rhizobacterial strain, host species and nitrogen level.root clusters are bunches of hairy rootlets produced by >1800 species in nine families. the possible involvement of micro-organisms in root-cluster formation has produced conflicting results over the last 40 years. in addition, any effect of rhizobacteria on overall plant growth of root-cluster-bearing species remains unknown.201627288511
mobilization of pollutant-degrading bacteria by eukaryotic zoospores.the controlled mobilization of pollutant-degrading bacteria has been identified as a promising strategy for improving bioremediation performance. we tested the hypothesis whether the mobilization of bacterial degraders may be achieved by the action of eukaryotic zoospores. we evaluated zoospores that are produced by the soil oomycete pythium aphanidermatum as a biological vector, and, respectively, the polycyclic aromatic hydrocarbon (pah)-degrading bacteria mycobacterium gilvum vm552 and pseudo ...201627286642
coexistence of two d-lactate-utilizing systems in pseudomonas putida kt2440.it is advantageous for rhizosphere-dwelling microorganisms to utilize organic acids such as lactate. pseudomonas putida kt2440 is one of the most widely studied rhizosphere-dwelling model organisms. the p. putida kt2440 genome contains an nad-dependent d-lactate dehydrogenase encoding gene, but mutation of this gene does not play a role in d-lactate utilization. instead, it was found that d-lactate utilization in p. putida kt2440 proceeds via a multidomain nad-independent d-lactate dehydrogenase ...201627264531
3-chloro-1,2-propanediol biodegradation by ca-alginate immobilized pseudomonas putida dsm 437 cells applying different processes: mass transfer effects.3-chloro-1,2-propanediol (3-cpd) biodegradation by ca-alginate immobilized pseudomonas putida cells was performed in batch system, continuous stirred tank reactor (cstr), and packed-bed reactor (pbr). batch system exhibited higher biodegradation rates and 3-cpd uptakes compared to cstr and pbr. the two continuous systems (cstr and pbr) when compared at 200 mg/l 3-cpd in the inlet exhibited the same removal of 3-cpd at steady state. external mass-transfer limitations are found negligible at all s ...201627262716
nitrile-synthesizing enzyme: screening, purification and characterization.cyanide is known as a toxic compound for almost all living organisms. we have searched for cyanide-resistant bacteria from the soil and stock culture collection of our laboratory, and have found the existence of a lot of microorganisms grown on culture media containing 10 mm potassium cyanide. almost all of these cyanide-resistant bacteria were found to show β-cyano-l-alanine (β-cnala) synthetic activity. β-cnala synthase is known to catalyze nitrile synthesis: the formation of β-cnala from pota ...201627250663
from dirt to industrial applications: pseudomonas putida as a synthetic biology chassis for hosting harsh biochemical reactions.the soil bacterium pseudomonas putida is endowed with a central carbon metabolic network capable of fulfilling high demands of reducing power. this situation arises from a unique metabolic architecture that encompasses the partial recycling of triose phosphates to hexose phosphates-the so-called edemp cycle. in this article, the value of p. putida as a bacterial chassis of choice for contemporary, industrially-oriented metabolic engineering is addressed. the biochemical properties that make this ...201627239751
complete biodegradation of chlorpyrifos by engineered pseudomonas putida cells expressing surface-immobilized laccases.the long-term abuse use of chlorpyrifos-like pesticides in agriculture and horticulture has resulted in significant soil or water contamination and a worldwide ecosystem threat. in this study, the ability of a solvent-tolerant bacterium, pseudomonas putida mb285, with surface-displayed bacterial laccase, to biodegrade chlorpyrifos was investigated. the results of compositional analyses of the degraded products demonstrate that the engineered mb285 was capable of completely eliminating chlorpyrif ...201627231878
impact of pnpr, a lysr-type regulator-encoding gene, on the cellular processes of pseudomonas putida dll-e4.lysr-type transcriptional regulators (lttrs) regulate various cellular processes in bacteria. pnpr is an lttr-encoding gene involved in the regulation of hydroquinone (hq) degradation, and its effects on the cellular processes of pseudomonas putida dll-e4 were investigated at the physiological, biochemical and molecular levels. reverse transcription polymerase chain reaction revealed that pnpr positively regulated its own expression and that of the pnpc1c2decx1x2 operon; additionally, pnpr parti ...201627190157
biofilm formation-defective mutants in pseudomonas putida.out of 8000 candidates from a genetic screening for pseudomonas putida kt2442 mutants showing defects in biofilm formation, 40 independent mutants with diminished levels of biofilm were analyzed. most of these mutants carried insertions in genes of the lap cluster, whose products are responsible for synthesis, export and degradation of the adhesin lapa. all mutants in this class were strongly defective in biofilm formation. mutants in the flagellar regulatory genes fleq and flhf showed similar d ...201627190143
sulfhydryl binding sites within bacterial extracellular polymeric substances.in this study, the concentration of sulfhydryl sites on bacterial biomass samples with and without extracellular polymeric substances (eps) was measured in order to determine the distribution of sulfhydryl sites on bacteria. three different approaches were employed for eps removal from pseudomonas putida, and the measured sulfhydryl concentrations on bacterial eps molecules are independent of the eps removal protocols used. prior to eps removal, the measured sulfhydryl sites within p. putida sam ...201627177017
enhancing indigo production by over-expression of the styrene monooxygenase in pseudomonas putida.as an important traditional blue dye, indigo has been used in food and textile industry for centuries, which can be produced via the styrene oxygenation pathway in pseudomonas putida. hence, the styrene monooxygenase gene styab and oxide isomerase gene styc are over-expressed in p. putida to investigate their roles in indigo biosynthesis. rt-qpcr analysis indicated that transcriptions of stya and styb were increased by 2500- and 750-folds in the styab over-expressed strain b4-01, compared with t ...201627154464
transcriptional kinetics of the cross-talk between the ortho-cleavage and tol pathways of toluene biodegradation in pseudomonas putida mt-2.the tol plasmid promoters are activated by toluene leading to gene expression responsible for the degradation of the environmental signal. benzoate is formed as an intermediate, activating the benr protein of the chromosomal ortho-cleavage pathway that up-regulates the chromosomal pbena promoter and the tol pm promoter resulting in cross-talk between the two networks. herein, the transcriptional kinetics of the pbenr and pbena promoters in conjunction with tol promoters was monitored by real-tim ...201627046069
loop-grafted old yellow enzymes in the bienzymatic cascade reduction of allylic alcohols.the enzymatic reduction of c=c bonds in allylic alcohols with old yellow enzymes represents a challenging task, due to insufficient activation through the hydroxy group. in our work, we coupled an alcohol dehydrogenase with three wild-type ene reductases-namely nicotinamide-dependent cyclohex-2-en-1-one reductase (ncr) from zymomonas mobilis, oye1 from saccharomyces pastorianus and morphinone reductase (mr) from pseudomonas putida m10-and four rationally designed β/α loop variants of ncr in the ...201627037735
pseudomonas putida biofilm dynamics following a single pulse of silver nanoparticles.pseudomonas putida mono-species biofilms were exposed to silver nanoparticles (ag nps) in artificial wastewater (aw) under hydrodynamic conditions. specifically, 48 h old biofilms received a single pulse of ag nps at 0, 0.01, 0.1, 1, 10 and 100 mg l(-1) for 24 h in confocal laser scanning microscopy (clsm) compatible flow-cells. the biofilm dynamics (in terms of morphology, viability and activity) were characterised at 48, 72 and 96 h. consistent patterns were found across flow-cells and experim ...201627031799
high resolution structures of periplasmic glucose-binding protein of pseudomonas putida csv86 reveal structural basis of its substrate specificity.periplasmic substrate-binding proteins (sbps) bind to the specific ligand with high affinity and mediate their transport into the cytoplasm via the cognate inner membrane atp-binding cassette proteins. because of low sequence identities, understanding the structural basis of substrate recognition by sbps has remained very challenging. there are several structures available for the ligand-bound sugar sbps, but very few unliganded structures are reported. no structural data are available for sugar ...201626861882
mechanistic understanding of reduced agnp phytotoxicity induced by extracellular polymeric substances.a knowledge gap concerning the potential effects of extracellular polymeric substances (eps), a common organic material but highly variable in their composition of microbial origin, on the fate and phytotoxicity of silver nanoparticles (agnp) still remains. a 48-h root elongation toxicity test showed that agnp toxicity to wheat triticum aestivum l. was dramatically alleviated by eps isolated from pseudomonas putida, as revealed by 7-59% increase in relative root elongation (rre), 8-99% increase ...201626808239
comparisons of the transferability of plasmids pcar1, pb10, r388, and nah7 among pseudomonas putida at different cell densities.the transferability of plasmids pcar1, pb10, r388, and nah7 was compared using the same donor-recipient system at different cell density combinations in liquid or on a solid surface. pcar1 was efficiently transferred in liquid, whereas the other plasmids were preferentially transferred on a solid surface. difference of liquid or solid affected the transfer frequency especially at lower cell densities.201626806196
metabolic engineering of pseudomonas putida kt2440 for complete mineralization of methyl parathion and γ-hexachlorocyclohexane.agricultural soils are often cocontaminated with multiple pesticides. unfortunately, microorganisms isolated from natural environments do not possess the ability to simultaneously degrade different classes of pesticides. currently, we can use the approaches of synthetic biology to create a strain endowed with various catabolic pathways that do not exist in a natural microorganism. here, we describe the metabolic engineering of a biosafety pseudomonas putida strain kt2440 for complete mineralizat ...201626854500
c-di-gmp regulates the expression of lapa and bcs operons via fleq in pseudomonas putida kt2440.cyclic diguanylate (c-di-gmp) positively modulates the production of biofilm matrix components from the transcriptional to the post-translational level in a variety of bacterial species. however, mechanisms by which it regulates these opponents in pseudomonas putida kt2440 remain unclear. here we show that c-di-gmp regulates the adhesin lapa, lapf and exopolysaccharides bcs, pea at transcriptional level. transcriptional regulator fleq is required for the modulation of lapa and bcs expression by ...201627120564
bio-statistical enhancement of acyl transfer activity of amidase for biotransformation of n-substituted aromatic amides.acyl transfer activity (ata) of amidase transfers an acyl group of different amides to hydroxylamine to form the corresponding hydroxamic acid. bacterial isolate br-1 was isolated from cyanogenic plant cirsium vulgare rhizosphere and identified as pseudomonas putida br-1 by 16s rdna sequencing. this organism exhibited high ata for the biotransformation of n-substituted aromatic amide to the corresponding hydroxamic acid. optimization of media, tryptone (0.6%), inducer, ph 8.5, and a growth tempe ...201627118077
genome-wide mapping of transcription start sites yields novel insights into the primary transcriptome of pseudomonas putida.the environmental bacterium pseudomonas putida is an organism endowed with a versatile metabolism and stress tolerance traits that are desirable in an efficient production organism. in this work, differential rna sequencing was used to investigate the primary transcriptome and rna regulatory elements of p. putida strain kt2440. a total of 7937 putative transcription start sites (tsss) were identified, where over two-thirds were located either on the opposite strand or internal to annotated genes ...201627111755
broad-host-range prouser vectors enable fast characterization of inducible promoters and optimization of p-coumaric acid production in pseudomonas putida kt2440.pseudomonas putida kt2440 has gained increasing interest as a host for the production of biochemicals. because of the lack of a systematic characterization of inducible promoters in this strain, we generated prouser broad-host-expression plasmids that facilitate fast uracil-based cloning. a set of prouser-reporter vectors was further created to characterize different inducible promoters. the prhab and pm promoters were orthogonal and showed titratable, high, and homogeneous expression. to optimi ...201627092814
a pseudomonas putida cbrb transposon insertion mutant displays a biofilm hyperproducing phenotype that is resistant to dispersal.the cbrab two-component system in the pseudomonads controls a variety of metabolic and behavioural traits required for its adaptation to changing environmental conditions, including the uptake or assimilation of certain carbon sources, and processes such as chemotaxis or stress tolerance. in this work we characterise a minitn5-luxab-km transposon insertion mutant in cbrb (mpo406) in pseudomonas putida leading to a biofilm overproducing phenotype that is not dispersed when nutrients are depleted. ...201627085034
methylmercury degradation by pseudomonas putida v1.environmental contamination of mercury (hg) has caused public health concerns with focuses on the neurotoxic substance methylmercury, due to its bioaccumulation and biomagnification in food chains. the goals of the present study were to examine: (i) the transformation of methylmercury, thimerosal, phenylmercuric acetate and mercuric chloride by cultures of pseudomonas putida v1, (ii) the presence of the genes mera and merb in p. putida v1, and (iii) the degradation pathways of methylmercury by p ...201627062344
ventosimonas gracilis gen. nov., sp. nov., a member of the gammaproteobacteria isolated from cephalotes varians ant guts representing a new family, ventosimonadaceae fam. nov., within the order 'pseudomonadales'.cephalotes 'turtle' ants are known to harbor a core group of gut symbionts, including members belonging to the gammaproteobacteria. here, we describe the cultivation and characterization of strain cv58t, a novel member of the gammaproteobacteria order pseudomonadales isolated from the guts of the ant cephalotes varians. strain cv58t was rod-shaped, gram-stain-negative, non-motile and formed pale-yellow colonies on trypticase soy agar. optimum growth occurred under an atmosphere of 4-20 % (v/v) o ...201627054961
biodegradation of chlorpyrifos by bacterial genus pseudomonas.chlorpyrifos is an organophosphorus pesticide commonly used in agriculture. it is noxious to a variety of organisms that include living soil biota along with beneficial arthropods, fish, birds, humans, animals, and plants. exposure to chlorpyrifos may cause detrimental effects as delayed seedling emergence, fruit deformities, and abnormal cell division. contamination of chlorpyrifos has been found about 24 km from the site of its application. there are many physico-chemical and biological approa ...201626837064
the toxin grat inhibits ribosome biogenesis.most bacteria encode numerous chromosomal toxin-antitoxin (ta) systems that are proposed to contribute to stress tolerance, as they are able to shift the cells to a dormant state. toxins act on a variety of targets with the majority attacking the translational apparatus. intriguingly, the toxicity mechanisms of even closely related toxins may differ essentially. here, we report on a new type of ta toxin that inhibits ribosome biogenesis. grat of the grata system has previously been described in ...201626833678
a pseudomonas putida double mutant deficient in butanol assimilation: a promising step for engineering a biological biofuel production platform.biological production in heterologous hosts is of interest for the production of the c4 alcohol (butanol) and other chemicals. however, some hurdles need to be overcome in order to achieve an economically viable process; these include avoiding the consumption of butanol and maintaining tolerance to this solvent during production. pseudomonas putida is a potential host for solvent production; in order to further adapt p. putida to this role, we generated mini-tn5 mutant libraries in strain bird-1 ...201626818251
numerical modelling of biophysicochemical effects on multispecies reactive transport in porous media involving pseudomonas putida for potential microbial enhanced oil recovery application.ph and resident time of injected slug plays a critical role in characterizing the reservoir for potential microbial enhanced oil recovery (meor) application. to investigate meor processes, a multispecies (microbes-nutrients) reactive transport model in porous media was developed by coupling kinetic and transport model. the present work differs from earlier works by explicitly determining parametric values required for kinetic model by experimental investigations using pseudomonas putida at diffe ...201627030954
comparative study of wastewater treatment and nutrient recycle via activated sludge, microalgae and combination systems.algal-bacterial synergistic cultivation could be an optional wastewater treatment technology in temperate areas. in this study, a locally screened vigorous chlorella strain was characterized and then it was used in a comparative study of wastewater treatment and nutrient recycle assessment via activated sludge (as), microalgae and their combination systems. chlorella sp. cultured with as in light showed the best performance, in which case the removal efficiencies of cod, nh3-n and tp were 87.3%, ...201626995615
tactic response of bacteria to zero-valent iron nanoparticles.the microbial assessment of pollutant toxicity rarely includes behavioral responses. in this study, we investigated the tactic response of pseudomonas putida g7, a representative of soil bacterium, towards engineered zero-valent iron nanoparticles (nzvis), as a new end-point assessment of toxicity. the study integrated the characterization of size distribution and charge of nzvis and tactic reaction response by means of inverted capillary assay and computer-assisted motion analysis of motility b ...201626967351
rationally rewiring the connectivity of the xylr/pu regulatory node of the m-xylene degradation pathway in pseudomonas putida.the xylr/pu regulatory node of the m-xylene biodegradation pathway of pseudomonas putida mt-2 is one of the most intricate cases of processing internal and external cues into a single controlling element. despite this complexity, the performance of the regulatory system is determined in vivo only by the occupation of pu by m-xylene-activated xylr and σ(54)-rnap. the stoichiometry between these three elements defines natural system boundaries that outline a specific functional space. this space c ...201626961967
photoactivation reduces side-chain dynamics of a lov photoreceptor.we used neutron-scattering experiments to probe the conformational dynamics of the light, oxygen, voltage (lov) photoreceptor ppsb1-lov from pseudomonas putida in both the dark and light states. global protein diffusion and internal macromolecular dynamics were measured using incoherent neutron time-of-flight and backscattering spectroscopy on the picosecond to nanosecond timescales. global protein diffusion of ppsb1-lov is not influenced by photoactivation. observation-time-dependent global dif ...201626958884
airborne toluene removal for minimizing occupational health exposure by means of a trickle-bed biofilter.the paper presents the experimental results on a biotrickling pilot plant, with a water scrubber as pre-treatment, finalized to the treatment of an airborne toluene stream in a working place. the air stream was characterized by a very high variability of the inlet concentrations of toluene (range: 4.35-68.20 mg nm(-3)) with an average concentrations of 16.41 mg nm(-3). the pilot plant has proved its effectiveness in toluene removal, along a 90-day experimentation period, in steady-state conditio ...201626946504
biological manganese oxidation by pseudomonas putida in trickling filters.biological oxidation has been researched as a viable alternative for treating waters with high manganese (mn) concentrations, typically found in mine drainage or in some geological formations. in this study, laboratory-scale trickling filters were constructed to compare the mn removal efficiency between filters inoculated with the mn oxidizing bacteria, pseudomonas putida, and filters without inoculation. manganese oxidation and removal was found to be significantly greater in trickling filters ...201626943637
toxicity of graphene oxide on growth and metabolism of pseudomonas putida.the increasing consumption of graphene derivatives leads to greater presence of these materials in wastewater treatment plants and ecological systems. the toxicity effect of graphene oxide (go) on the microbial functions involved in the biological wastewater treatment process is studied, using pseudomonas putida and salicylic acid (sa) as bacterial and pollutant models. a multiparametric flow cytometry (fc) method has been developed to measure the metabolic activity and viability of p. putida in ...201626937871
metabolomics reveals the physiological response of pseudomonas putida kt2440 (uwc1) after pharmaceutical exposure.human pharmaceuticals have been detected in wastewater treatment plants, rivers, and estuaries throughout europe and the united states. it is widely acknowledged that there is insufficient information available to determine whether prolonged exposure to low levels of these substances is having an impact on the microbial ecology in such environments. in this study we attempt to measure the effects of exposing cultures of pseudomonas putida kt2440 (uwc1) to six pharmaceuticals by looking at differ ...201626932201
release of outer membrane vesicles in pseudomonas putida as a response to stress caused by cationic surfactants.pseudomonas putida a (atcc 12633), a degrader of cationic surfactants, releases outer membrane vesicles (omvs) when grown with tetradecyltrimethylammonium bromide (ttab) as the sole carbon, nitrogen and energy source. the omvs exhibit a bilayer structure and were found to be composed of lipopolysaccharides, proteins and phospholipids (pls) such as cardiolipin, phosphatidylcholine, phosphatidic acid and phosphatidylglycerol (pg). the omvs showed a marked increase in the pg content, approximately ...201626925774
the revisited genome of pseudomonas putida kt2440 enlightens its value as a robust metabolic chassis.by the time the complete genome sequence of the soil bacterium pseudomonas putida kt2440 was published in 2002 (nelson et al., ) this bacterium was considered a potential agent for environmental bioremediation of industrial waste and a good colonizer of the rhizosphere. however, neither the annotation tools available at that time nor the scarcely available omics data-let alone metabolic modeling and other nowadays common systems biology approaches-allowed them to anticipate the astonishing capac ...201626913973
characterization of rhamnolipids by liquid chromatography/mass spectrometry after solid-phase extraction.rhamnolipids are surface-active agents with a broad application potential that are produced in complex mixtures by bacteria of the genus pseudomonas. analysis from fermentation broth is often characterized by laborious sample preparation and requires hyphenated analytical techniques like liquid chromatography coupled to mass spectrometry (lc-ms) to obtain detailed information about sample composition. in this study, an analytical procedure based on chromatographic method development and characte ...201626879646
structural and kinetic characterization of the 4-carboxy-2-hydroxymuconate hydratase from the gallate and protocatechuate 4,5-cleavage pathways of pseudomonas putida kt2440.the bacterial catabolism of lignin and its breakdown products is of interest for applications in industrial processing of ligno-biomass. the gallate degradation pathway ofpseudomonas putidakt2440 requires a 4-carboxy-2-hydroxymuconate (chm) hydratase (galb), which has a 12% sequence identity to a previously identified chm hydratase (ligj) fromsphingomonassp. syk-6. the structure of galb was determined and found to be a member of the pig-ln-acetylglucosamine deacetylase family; galb is structural ...201626867578
engineering synthetic bacterial consortia for enhanced desulfurization and revalorization of oil sulfur compounds.the 4s pathway is the most studied bioprocess for the removal of the recalcitrant sulfur of aromatic heterocycles present in fuels. it consists of three sequential functional units, encoded by the dszabcd genes, through which the model compound dibenzothiophene (dbt) is transformed into the sulfur-free 2-hydroxybiphenyl (2hbp) molecule. in this work, a set of synthetic dsz cassettes were implanted in pseudomonas putida kt2440, a model bacterial "chassis" for metabolic engineering studies. the co ...201626802977
pseudomonas putida kt2440 markerless gene deletion using a combination of λ red recombineering and cre/loxp site-specific recombination.pseudomonas putida kt2440 is a saprophytic, environmental microorganism that plays important roles in the biodegradation of environmental toxic compounds and production of polymers, chemicals and secondary metabolites. gene deletion of kt2440 usually involves cloning of the flanking homologous fragments of the gene of interest into a suicide vector followed by transferring into kt2440 via triparental conjugation. selection and counterselection steps are then employed to generate gene deletion mu ...201626802072
interactions of eps with soil minerals: a combination study by itc and clsm.the adsorption of extracellular polymeric substances (eps) from pseudomonas putida on montmorillonite, kaolinite and goethite was investigated as a function of ph using batch studies coupled with confocal laser scanning microscopy (clsm) and isothermal titration calorimetry (itc). characterization by raman spectroscopy, x-ray photoelectron spectroscopy (xps) and fourier transform infrared (ftir) spectroscopy showed that the extracted eps contained carboxyl, phosphoryl, amino, and hydroxyl on fun ...201626638177
transcription factor levels enable metabolic diversification of single cells of environmental bacteria.transcriptional noise is a necessary consequence of the molecular events that drive gene expression in prokaryotes. however, some environmental microorganisms that inhabit polluted sites, for example, the m-xylene degrading soil bacterium pseudomonas putida mt-2 seem to have co-opted evolutionarily such a noise for deploying a metabolic diversification strategy that allows a cautious exploration of new chemical landscapes. we have examined this phenomenon under the light of deterministic and sto ...201626636554
integrated micro-biochemical approach for phytoremediation of cadmium and lead contaminated soils using gladiolus grandiflorus l cut flower.the potential of vermicompost, elemental sulphur, thiobacillus thiooxidans and pseudomonas putida for phytoremediation is well known individually but their integrated approach has not been discovered so far. the present work highlights the consideration of so far overlooked aspects of their integrated treatment by growing the ornamental plant, gladiolus grandiflorus l in uncontaminated and sewage-contaminated soils (sulphur-deficient alluvial entisols, ph 7.6-7.8) for phytoremediation of cadmium ...201626615479
protective role of glycerol against benzene stress: insights from the pseudomonas putida proteome.chemical activities of hydrophobic substances can determine the windows of environmental conditions over which microbial systems function and the metabolic inhibition of microorganisms by benzene and other hydrophobes can, paradoxically, be reduced by compounds that protect against cellular water stress (bhaganna et al. in microb biotechnol 3:701-716, 2010; cray et al. in curr opin biotechnol 33:228-259, 2015a). we hypothesized that this protective effect operates at the macromolecule structure- ...201626612269
3-fluorophenmetrazine, a fluorinated analogue of phenmetrazine: studies on in vivo metabolism in rat and human, in vitro metabolism in human cyp isoenzymes and microbial biotransformation in pseudomonas putida and wastewater using gc and lc coupled to (hr)-ms techniques.wastewater-based epidemiology (wbe) as means to estimate illicit drug and new psychoactive substance (nps) consumption with spatial and temporal resolution is gaining increasing attention. in order to evaluate a given nps using wbe, in vivo metabolism and microbial biotransformation of excretion products and unchanged compounds need evaluation. the aims of this study were to identify in vivo phase i and ii metabolites of the nps 3-fluorophenmetrazine (3-fpm) in human and rat urine and study the ...201627372653
competitive adsorption of pb and cd on bacteria-montmorillonite composite.the characteristics and mechanisms of competitive adsorption of trace metals on bacteria-associated clay mineral composites have never been studied, despite their being among the most common organic-mineral complexes in geological systems. herein, competitive adsorption of pb and cd on pseudomonas putida-montmorillonite composite was investigated through adsorption-desorption experiment, isothermal titration calorimetry (itc), and synchrotron micro x-ray fluorescence (μ-xrf). from the experiment ...201627566847
spatial pattern of copper phosphate precipitation involves in copper accumulation and resistance of unsaturated pseudomonas putida cz1 biofilm.bacterial biofilms are spatially structured communities that contain bacterial cells with a wide range of physiological states. the spatial distribution and speciation of copper in unsaturated pseudomonas putida cz1 biofilms that accumulated 147.0 mg copper per g dry weight were determined by transmission electron microscopy coupled with energy dispersive x-ray analysis, and micro-x-ray fluorescence microscopy coupled with micro-x-ray absorption near edge structure (micro-xanes) analysis. it was ...201627558435
pyridine nucleotide transhydrogenases enable redox balance of pseudomonas putida during biodegradation of aromatic compounds.the metabolic versatility of the soil bacterium pseudomonas putida is reflected by its ability to execute strong redox reactions (e.g., mono- and di-oxygenations) on aromatic substrates. biodegradation of aromatics occurs via the pathway encoded in the archetypal tol plasmid pww0, yet the effect of running such oxidative route on redox balance against the background metabolism of p. putida remains unexplored. to answer this question, the activity of pyridine nucleotide transhydrogenases (that ca ...201627348295
novel polyhydroxyalkanoate copolymers produced in pseudomonas putida by metagenomic polyhydroxyalkanoate synthases.bacterially produced biodegradable polyhydroxyalkanoates (phas) with versatile properties can be achieved using different pha synthases (phacs). this work aims to expand the diversity of known phacs via functional metagenomics and demonstrates the use of these novel enzymes in pha production. complementation of a pha synthesis-deficient pseudomonas putida strain with a soil metagenomic cosmid library retrieved 27 clones expressing either class i, class ii, or unclassified pha synthases, and many ...201627333909
in silico analysis for prediction of degradative capacity of pseudomonas putida sf1.the study employs draft genome sequence data to explore p-nitrophenol (pnp) degradation activity of pseudomonas putida strain sf-1 at a genomic scale. annotation analysis proposes that the strain sf1 not only possesses the gene cluster for pnp utilization but also for the utilization of benzoate, catechol, hydroxybenzoate, protocatechuate, and homogentisate. further, the analysis was carried out to understand more details of pnp 4-monooxygenase and its regulator. a comparative analysis of pnp 4- ...201627317892
signaling states of a short blue-light photoreceptor protein ppsb1-lov revealed from crystal structures and solution nmr spectroscopy.light-oxygen-voltage (lov) domains represent the photo-responsive domains of various blue-light photoreceptor proteins and are widely distributed in plants, algae, fungi, and bacteria. here, we report the dark-state crystal structure of ppsb1-lov, a slow-reverting short lov protein from pseudomonas putida that is remarkably different from our previously published "fully light-adapted" structure [1]. a direct comparison of the two structures provides insight into the light-activated signaling mec ...201627291287
the response of aggregated pseudomonas putida cp1 cells to uv-c and uv-a/b disinfection.uv radiation is a spread method used worldwide for the disinfection of water. however, much of the research on the disinfection of bacterial cells by uv has focused on planktonic cells. many bacterial cells in nature are present in clumps or aggregates, and these aggregates, which are more resistant to disinfection than their planktonic counterparts, can be problematic in engineered water systems. the current research used pseudomonas putida (p. putida) cp1, an environmental and non-pathogenic m ...201627655528
content of cardiolipin of the membrane and sensitivity to cationic surfactants in pseudomonas putida.to establish the role of cardiolipin (cl) of the membrane in response to the presence of tetradecyltrimethylammonium in pseudomonas putida a (atcc 12633).201627442261
robust at-line quantification of poly(3-hydroxyalkanoate) biosynthesis by flow cytometry using a bodipy 493/503-syto 62 double-staining.poly(3-hydroxyalkanoates) (phas) are bio-based and biodegradable polyesters which have been considered as a promising alternative to petrol-based plastics. their bacterial production is a dynamic process in which intracellular polymerization and depolymerization are closely linked and depend on the availability of carbon substrates and other nutrients. these dynamics require a fast and quantitative method to determine the optimal harvest-time of pha containing cells or to adjust carbon supply. i ...201627720900
biofilm adaptation to iron availability in the presence of biotite and consequences for chemical weathering.bacteria in nature often live within biofilms, exopolymeric matrices that provide a favorable environment that can differ markedly from their surroundings. biofilms have been found growing on mineral surfaces and are expected to play a role in weathering those surfaces, but a clear understanding of how environmental factors, such as trace-nutrient limitation, influence this role is lacking. here, we examine biofilm development by pseudomonas putida in media either deficient or sufficient in fe d ...201627384343
u(vi) biosorption by bi-functionalized pseudomonas putida @ chitosan bead: modeling and optimization using rsm.in this work, pseudomonas putida cells immobilized into chitosan beads (picb) were synthesized to investigate the impact of microorganism entrapment on biosorption capacity of prepared biosorbent for u(vi) biosorption from aqueous solutions. response surface methodology (rsm) based on central composite design (ccd) was utilized to evaluate the performance of the picb in comparison with chitosan beads (cb) under batch mode. performing experiments under optimal condition sets viz. ph 5, initial u( ...201627180295
role of conserved met112 residue in the catalytic activity and stability of ketosteroid isomerase.ketosteroid isomerase (3-oxosteroid δ(5)-δ(4)-isomerase, ksi) from pseudomonas putida catalyzes allylic rearrangement of the 5,6-double bond of δ(5)-3-ketosteroid to 4,5-position by stereospecific intramolecular transfer of a proton. the active site of ksi is formed by several hydrophobic residues and three catalytic residues (tyr14, asp38, and asp99). in this study, we investigated the role of a hydrophobic met112 residue near the active site in the catalysis, steroid binding, and stability of ...201627375051
rhizosphere selection of pseudomonas putida kt2440 variants with increased fitness associated to changes in gene expression.as the interface between plant roots and soil, the rhizosphere is a complex environment where nutrients released by the plant promote microbial growth. increasing evidences indicate that the plant also exerts a selective pressure on microbial populations in the rhizosphere, favouring colonization by certain groups. in this work, we have designed an experimental setup to begin analysing the evolution of a specific bacterial population in the rhizosphere, using pseudomonas putida kt2440 as model o ...201627487165
stepwise simulation of 3,5-dihydro-5-methylidene-4h-imidazol-4-one (mio) biogenesis in histidine ammonia-lyase.a 3,5-dihydro-5-methylidene-4h-imidazol-4-one (mio) electrophilic moiety is post-translationally and autocatalytically generated in homotetrameric histidine ammonia-lyase (hal) and other enzymes containing the tripeptide ala-ser-gly in a suitably positioned loop. the backbone cyclization step is identical to that taking place during fluorophore formation in green fluorescent protein from the tripeptide ser-tyr-gly, but dehydration, rather than dehydrogenation by molecular oxygen, is the reaction ...201627682658
biosorption of aluminum through the use of non-viable biomass of pseudomonas putida.living and non-living biomass of pseudomonas putida a (atcc 12633) was used as biosorbent for the removing of al(3+) from aqueous solutions. the process was stable with time, efficient at ph 4.3 and between 15°c and 42°c. two isotherms models were applied to describe the interaction between the biosorbent and al(3+). non-living biomass of p. putida a (atcc 12633) was found to be the most efficient at adsorbing al(3+) with a maximum sorption capacity of 0.55mg al(3+)/gr adsorbent and with 36×10(5 ...201627485814
proteome analysis of pseudomonas putida f1 genes induced in soil environments.knowledge of the gene expression dynamics of a single soil bacterial strain contributes to the understanding of its behaviour, physiological state and surrounding microenvironment. genes expressed in soil environments rather than in laboratory media are considered to particularly relevant. here, we compared genome-wide gene expression profiles of the bacterium pseudomonas putida f1 inoculated in three different types of nonsterile soils deduced using proteome analysis via sodium dodecyl sulfate- ...201627452675
production of glucaric acid from myo-inositol in engineered pichia pastoris.a potential myo-inositol oxygenase (ppmiox) was identified as a functional enzyme and a glucaric acid synthetic pathway was firstly constructed in pichia pastoris. coexpression of the native ppmiox and the urinate dehydrogenase (udh) from pseudomonas putida kt2440 led to obvious accumulation of glucaric acid (90.46±0.04mg/l) from myo-inositol whereas no glucaric acid was detected from glucose. in comparison, coexpression of the heterologous mouse miox (mmiox) and udh resulted in higher titers of ...201627444324
identification and validation of novel small proteins in pseudomonas putida.small proteins of 50 amino acids or less have been understudied due to difficulties that impede their annotation and detection. in order to obtain information on small open reading frames (sorfs) in pseudomonas putida, bioinformatic and proteomic approaches were used to identify putative sorfs in the well-characterized strain kt2440. a plasmid-based system was established for sorf validation, enabling expression of c-terminal sequential peptide affinity tagged variants and their detection via pr ...201627717237
synthesis gas (syngas)-derived medium-chain-length polyhydroxyalkanoate synthesis in engineered rhodospirillum rubrum.the purple nonsulfur alphaproteobacterium rhodospirillum rubrum s1 was genetically engineered to synthesize a heteropolymer of mainly 3-hydroxydecanoic acid and 3-hydroxyoctanoic acid [p(3hd-co-3ho)] from co- and co2-containing artificial synthesis gas (syngas). for this, genes from pseudomonas putida kt2440 coding for a 3-hydroxyacyl acyl carrier protein (acp) thioesterase (phag), a medium-chain-length (mcl) fatty acid coenzyme a (coa) ligase (pp_0763), and an mcl polyhydroxyalkanoate (pha) syn ...201627520812
a pseudo-outbreak of pseudomonas putida and stenotrophomonas maltophilia in a bronchoscopy unit.endoscopes represent the medical devices most commonly linked to health care-associated outbreaks and pseudo-outbreaks. most of the recent outbreaks and pseudo-outbreaks have resulted from contaminated automated endoscope reprocessors (aer) or the use of damaged or malfunctioning bronchoscopes or contaminated equipment.201627627819
self-regulation and interplay of rsm family proteins modulate the lifestyle of pseudomonas putida.in the plant-beneficial bacterium pseudomonas putida kt2440, three genes have been identified that encode posttranscriptional regulators of the csra/rsma family. their regulatory roles in the motile and sessile lifestyles of p. putida have been investigated by generating single-, double-, and triple-null mutants and by overexpressing each protein (rsma, rsme, and rsmi) in different genetic backgrounds. the rsm triple mutant shows reduced swimming and swarming motilities and increased biofilm for ...201627422830
pseudomonas putida as a platform for the synthesis of aromatic compounds.aromatic compounds such as l-phenylalanine, 2-phenylethanol and trans-cinnamate are aromatic compounds of industrial interest. current trends support replacement of chemical synthesis of these compounds by 'green' alternatives produced in microbial cell factories. the solvent-tolerant pseudomonas putida dot-t1e strain was genetically modified to produce up to 1 g l-1 of l-phenylalanine. in order to engineer this strain, we carried out the following stepwise process: (1) we selected random mutant ...201627417954
a rapid method to estimate nadh regeneration rates in living cells.we introduce a rapid whole cell assay for the estimation of nadh regeneration rates based on the fluorescent dye resazurin. a co-feed of formate and glucose, known to increase the intrinsic nadh regeneration rate of p. putida kt2440, was chosen as model system for the validation of this assay.201627592588
structural and kinetic properties of the aldehyde dehydrogenase nahf, a broad substrate specificity enzyme for aldehyde oxidation.the salicylaldehyde dehydrogenase (nahf) catalyzes the oxidation of salicylaldehyde to salicylate using nad(+) as a cofactor, the last reaction of the upper degradation pathway of naphthalene in pseudomonas putida g7. the naphthalene is an abundant and toxic compound in oil and has been used as a model for bioremediation studies. the steady-state kinetic parameters for oxidation of aliphatic or aromatic aldehydes catalyzed by 6xhis-nahf are presented. the 6xhis-nahf catalyzes the oxidation of ar ...201627580341
responses of pseudomonas putida to zinc excess determined at the proteome level: pathways dependent and independent of colrs.zinc is an important micronutrient for bacteria, but its excess is toxic. recently, the colrs two-component system was shown to detect and respond to zinc excess and to contribute to zinc tolerance of pseudomonas putida. here, we applied a label-free whole-cell proteome analysis to compare the zinc-induced responses of p. putida and colr knockout. we identified dozens of proteins that responded to zinc in a colr-independent manner, among others, known metal efflux systems czccba1, czccba2, cada2 ...201627797207
toxicity testing of pristine and aged silver nanoparticles in real wastewaters using bioluminescent pseudomonas putida.impact of aging on nanoparticle toxicity in real matrices is scarcely investigated due to a lack of suitable methodologies. herein, the toxicity of pristine and aged silver nanoparticles (ag nps) to a bioluminescent pseudomonas putida bioreporter was measured in spiked crude and final wastewater samples (cws and fws, respectively) collected from four wastewater treatment plants (wwtps). results showed lower toxicity of pristine ag nps in cws than in fws. the effect of the matrix on the eventual ...201628344306
effects of even and odd number fatty acids cofeeding on pha production and composition in pseudomonas putida bet001 isolated from palm oil mill effluent.the biosynthesis of medium-chain-length poly-3-hydroxyalkanoates by pseudomonas putida bet001 cultivated on mixed carbon sources was investigated. the mixed carbon sources consisted of heptanoic acid (ha) and oleic acid (oa). a relatively low pha content at 1.2% (w/w) and 11.4% (w/w) was obtained when ha or oa was used as the sole carbon source. when these fatty acids were supplied as a mixture, pha content increased threefold. interestingly, the mixture-derived pha composed of both odd and even ...201625643814
chemotaxis increases the residence time of bacteria in granular media containing distributed contaminant sources.the use of chemotactic bacteria in bioremediation has the potential to increase access to, and the biotransformation of, contaminant mass within the subsurface. this laboratory-scale study aimed to understand and quantify the influence of chemotaxis on the residence times of pollutant-degrading bacteria within homogeneous treatment zones. focus was placed on a continuous-flow sand-packed column in which a uniform distribution of naphthalene crystals created distributed sources of dissolved-phase ...201626605857
use of response surface method for maximizing the production of arginine deiminase by pseudomonas putida.statistically designed experiments were used to optimize the production of arginine deiminase (adi) by pseudomonas putida kt2440 in batch culture. a plackett-burman design involving eleven factors showed that adi production was most influenced by the initial ph and the initial concentrations of glucose and yeast extract. a central composite experimental design showed that the optimal values of these factors were 8.0, 10 g/l and 12.5 g/l, respectively. the other components of the optimal culture ...201628352521
a holistic view of polyhydroxyalkanoate metabolism in pseudomonas putida.polyhydroxyalkanoate (pha) metabolism has been traditionally considered as a futile cycle involved in carbon and energy storage. the use of cutting-edge technologies linked to systems biology has improved our understanding of the interaction between bacterial physiology, pha metabolism and other cell functions in model bacteria such as pseudomonas putida kt2440. pha granules or carbonosomes are supramolecular complexes of biopolyester and proteins that are essential for granule segregation durin ...201625556983
recombineering and i-scei-mediated pseudomonas putida kt2440 scarless gene deletion.pseudomonas putida kt2440 is a saprophytic, generally recognized as safe microorganism that plays important roles in the biodegradation and production of value-added chemicals. chromosomal gene deletion of p. putida kt2440 usually involves time-consuming gene coning, conjugal transfer and counterselection. recently, we developed a p. putida kt2440 markerless gene deletion method based on recombineering and cre/loxp site-specific recombination. pcr-based λ red recombineering circumvents the tedio ...201627765807
interactive effects of phosphorus and pseudomonas putida on chickpea (cicer arietinum l.) growth, nutrient uptake, antioxidant enzymes and organic acids exudation.phosphorus (p) availability in alkaline soils of arid and semi-arid regions is a major constraint for decreased crop productivity. use of plant growth promoting rhizobacteria (pgpr) may enhance plant growth through the increased plant antioxidation activity. additionally, pgpr may increase nutrient uptake by plants as a result of induced root exudation and rhizosphere acidification. the current study was aimed to investigate combined effects of p and pesudomonas putida (pgpr) on chickpea growth ...201627485620
a broad mercury resistant strain of pseudomonas putida secretes pyoverdine under limited iron conditions and high mercury concentrations.the pseudomonas putida fb1, known as a broad-spectrum mercury resistant strain, becomes yellow-green due to the secretion of pyoverdine (pvds) under limited iron conditions and high mercury concentrations. different modified nelson's media were obtained by adding mercury, iron, and the complexing agent nitrilotriacetic acid to demonstrate that the strain produces only the highest concentrations of pvds due to the induction with 25 µm hg(2+). an amount of 250 mg pvds was purified from the superna ...201627848043
elimination of persistent emerging micropollutants in a suspended-bed photocatalytic reactor: influence of operating conditions and combination with aerobic biological treatment.a larger, lab-scale photocatalytic suspended-bed reactor using tio2 sol-gel-coated expanded clay granules as a bed material was evaluated for oxidative removal of the persistent pharmaceuticals doxycycline, prednisolone, amoxicillin, and sulfamethizole, as well as their mixture, in ppm concentrations. the photocatalytic degradation potential of drug molecules increases as their adsorption affinity increases towards tio2-containing coatings. the performance of the photocatalytic reactor in the re ...201627830220
structural analysis provides mechanistic insight into nicotine oxidoreductase from pseudomonas putida.the first structure of nicotine oxidoreductase (nica2) was determined by x-ray crystallography. pseudomonas putida has evolved nicotine-degrading activity to provide a source of carbon and nitrogen. the structure establishes nica2 as a member of the monoamine oxidase family. residues 1-50 are disordered and may play a role in localization. the nicotine-binding site proximal to the isoalloxazine ring of flavin shows an unusual composition of the classical aromatic cage (w427 and n462). the active ...201627933790
isolation and characterization of bacteria that use furans as the sole carbon source.five bacterial strains were isolated from wastewater treatment facilities which were able to use furfural as the sole carbon source. based on 16s rrna phylogenetic analysis, these strains were identified as cupriavidus pinatubonensis (designated als1280), pigmentiphaga sp. (als1172), pseudomonas sp. bwdy (als1279), pseudomonas mendocina (als1131), and pseudomonas putida (als1267). in all cases, growth under oxygenated conditions on furfural was accompanied by the transient accumulation of 2-furo ...201626419660
biofilm removal using carbon dioxide aerosols without nitrogen purge.biofilms can cause serious concerns in many applications. not only can they cause economic losses, but they can also present a public health hazard. therefore, it is highly desirable to remove biofilms from surfaces. many studies on co2 aerosol cleaning have employed nitrogen purges to increase biofilm removal efficiency by reducing the moisture condensation generated during the cleaning. however, in this study, periodic jets of co2 aerosols without nitrogen purges were used to remove pseudomona ...201627842343
two-step bioleaching of copper and gold from discarded printed circuit boards (pcb).an effective strategy for environmentally sound biological recovery of copper and gold from discarded printed circuit boards (pcb) in a two-step bioleaching process was experimented. in the first step, chemolithotrophic acidophilic acidithiobacillus ferrivorans and acidithiobacillus thiooxidans were used. in the second step, cyanide-producing heterotrophic pseudomonas fluorescens and pseudomonas putida were used. results showed that at a 1% pulp density (10g/l pcb concentration), 98.4% of the co ...201626704063
hydrogen isotope fractionation as a tool to identify aerobic and anaerobic pah biodegradation.aerobic and anaerobic polycyclic aromatic hydrocarbon (pah) biodegradation was characterized by compound specific stable isotope analysis (csia) of the carbon and hydrogen isotope effects of the enzymatic reactions initiating specific degradation pathways, using naphthalene and 2-methylnaphtalene as model compounds. aerobic activation of naphthalene and 2-methylnaphthalene by pseudomonas putida ncib 9816 and pseudomonas fluorescens atcc 17483 containing naphthalene dioxygenases was associated wi ...201626855125
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