| a comparison of the sorption reactivity of bacteriogenic and mycogenic mn oxide nanoparticles. | biogenic mno2 minerals affect metal fate and transport in natural and engineered systems by strongly sorbing metals ions. the ability to produce mno2 is widely dispersed in the microbial tree of life, leading to potential differences in the minerals produced by different organisms. in this study, we compare the structure and reactivity of biogenic mn oxides produced by the biofilm-forming bacterium pseudomonas putida gb-1 and the white-rot fungus coprinellus sp. the rate of mn(ii) oxidation, and ... | 2015 | 25668070 |
| the phasin phaf controls bacterial shape and size in a network-forming strain of pseudomonas putida. | pseudomonas putida n, a poly-3-hydroxyalkonate (pha)-producing bacterium, showing ampicillin resistance, is an unusual strain. in the presence of this antibiotic, it grows as giant cells (25-50μm) forming complex networks inter-connected by micro-tubular structures. the transformation of this bacterium with a plasmid containing the gene phaf, which encodes a phasin involved in the molecular architecture of the pha-granules, (i) restores the wild-type phenotype by reducing both bacterial size and ... | 2015 | 25661838 |
| synergic role of the two ars operons in arsenic tolerance in pseudomonas putida kt2440. | the chromosome of pseudomonas putida kt2440 carries two clusters of genes, denoted ars1 and ars2, that are annotated as putative arsenic resistance operons. in this work, we present evidence that both operons encode functional arsenic-response regulatory genes as well as arsenic extrusion systems that confer resistance to both arsenite [as(iii)] and arsenate [as(v)]. transcriptional fusions of p(ars1) and p(ars2) to lacz revealed that expression of both operons was induced by arsenite and arsena ... | 2014 | 25646541 |
| 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 ... | 2016 | 25643814 |
| integrated engineering of β-oxidation reversal and ω-oxidation pathways for the synthesis of medium chain ω-functionalized carboxylic acids. | an engineered reversal of the β-oxidation cycle was exploited to demonstrate its utility for the synthesis of medium chain (6-10-carbons) ω-hydroxyacids and dicarboxylic acids from glycerol as the only carbon source. a redesigned β-oxidation reversal facilitated the production of medium chain carboxylic acids, which were converted to ω-hydroxyacids and dicarboxylic acids by the action of an engineered ω-oxidation pathway. the selection of a key thiolase (bktb) and thioesterase (ydii) in combinat ... | 2015 | 25638687 |
| effects of lb broth, naphthalene concentration, and acetone on the naphthalene degradation activities by pseudomonas putida g7. | luria-bertani broth and acetone were usually used in naphthalene degradation experiments as nutrient and solvent. however, their effect on the degradation was seldom mentioned. in this work, we investigated the effect of lb, naphthalene concentration, and acetone on the degradation of naphthalene by pseudomonas putida g7, which is useful for the degradation of naphthalene on future field remediation. by adding lb, the naphthalene degradation efficiencies and naphthalene dioxygenase were both dec ... | 2015 | 25630128 |
| toxic effect of environmentally relevant concentration of silver nanoparticles on environmentally beneficial bacterium pseudomonas putida. | silver nanoparticles (ag nps) are being increasingly used in many consumer products owing to their excellent antimicrobial properties. the continuous use of ag nps in consumer products will lead to environmental release. the present study evaluated the toxic effects and the possible underlying mechanism of ag nps on pseudomonas putida. ag np exposure inhibited growth of the cells. increased lipid peroxidation occurred coincident with suppression of the antioxidant defense system. ag np exposure ... | 2015 | 25627470 |
| the loss of function of phac1 is a survival mechanism that counteracts the stress caused by the overproduction of poly-3-hydroxyalkanoates in pseudomonas putidaδfadba. | the poly-3-hydroxylkanoate (pha)-overproducing mutant pseudomonas putida u δfadba (ppδfadba) lacks the genes encoding the main β-oxidation pathway (fadba). this strain accumulates enormous amounts of bioplastics when cultured in chemically defined media containing pha precursors (different n-alkanoic or n-aryl-alkanoic acids) and an additional carbon source. in medium containing glucose or 4-hydroxy-phenylacetate, the mutant does not accumulate phas and grows just as the wild type (p. putida u). ... | 2015 | 25627209 |
| aromatic catabolic pathway selection for optimal production of pyruvate and lactate from lignin. | lignin represents an untapped feedstock for the production of fuels and chemicals, but its intrinsic heterogeneity makes lignin valorization a significant challenge. in nature, many aerobic organisms degrade lignin-derived aromatic molecules through conserved central intermediates including catechol and protocatechuate. harnessing this microbial approach offers potential for lignin upgrading in modern biorefineries, but significant technical development is needed to achieve this end. catechol an ... | 2015 | 25617773 |
| development of eukaryotic zoospores within polycyclic aromatic hydrocarbon (pah)-polluted environments: a set of behaviors that are relevant for bioremediation. | in this study, we assessed the development (formation, taxis and settlement) of eukaryotic zoospores under different regimes of exposure to polycyclic aromatic hydrocarbons (pahs), which imitated environmental scenarios of pollution and bioremediation. with this aim, we used an oomycete, pythium aphanidermatum, as a source of zoospores and two pah-degrading bacteria (mycobacterium gilvum vm552 and pseudomonas putida g7). the oomycete and both bacteria were not antagonistic, and zoospore formatio ... | 2015 | 25617701 |
| effect of plant growth-promoting rhizobacteria inoculation on cadmium (cd) uptake by eruca sativa. | microbe-assisted phyto-remediation approach is widely applied and appropriate choice to reduce the environmental risk of heavy metals originated from contaminated soils. the present study was designed to screen out the nested belongings of eruca sativa plants and pseudomonas putida (atcc 39213) at varying cadmium (cd) levels and their potential to deal with cd uptake from soils. we carried out pot trial experiment by examining the soil containing e. sativa seedlings either treated with p. putida ... | 2015 | 25592913 |
| personal care product preservatives: risk assessment and mixture toxicities with an industrial wastewater. | the aquatic toxicity of eight preservatives frequently used in personal care products (pcps) (iodopropynyl butylcarbamate, bronopol, diazolidinyl urea, benzalkonium chloride, zinc pyrithione, propylparaben, triclosan and a mixture of methylchloroisothiazolinone and methylisothiazolinone) was assessed by means of two different approaches: a battery of bioassays composed of single species tests of bacteria (vibrio fischeri and pseudomonas putida) and protozoa (tetrahymena thermophila), and a whole ... | 2015 | 25585550 |
| integration of chemotaxis, transport and catabolism in pseudomonas putida and identification of the aromatic acid chemoreceptor pcay. | aromatic and hydroaromatic compounds that are metabolized through the β-ketoadipate catabolic pathway serve as chemoattractants for pseudomonas putida f1. a screen of p. putida f1 mutants, each lacking one of the genes encoding the 18 putative methyl-accepting chemotaxis proteins (mcps), revealed that pcay encodes the mcp required for metabolism-independent chemotaxis to vanillate, vanillin, 4-hydroxybenzoate, benzoate, protocatechuate, quinate, shikimate, as well as 10 substituted benzoates tha ... | 2015 | 25582673 |
| differential transcriptional response to antibiotics by pseudomonas putida dot-t1e. | multi-drug resistant bacteria are a major threat to humanity, especially because the current battery of known antibiotics is not sufficient to combat infections produced by these microbes. therefore, the study of how current antibiotics act and how bacteria defend themselves against antibiotics is of critical importance. pseudomonas putida dot-t1e exhibits an impressive array of rnd efflux pumps, which confer this microorganism high resistance to organic solvents and antibiotics that would kill ... | 2015 | 25581266 |
| carbon-limited fed-batch production of medium-chain-length polyhydroxyalkanoates by a phaz-knockout strain of pseudomonas putida kt2440. | a medium-chain-length poly-3-hydroxyalkanote (mcl-pha) depolymerase knockout mutant of pseudomonas putida kt2440 was produced by double homologous recombination. a carbon-limited shake-flask study confirmed that depolymerase activity was eliminated. lysis of both mutant and wild-type strains occurred under these conditions. in carbon-limited, fed-batch culture, the yield of unsaturated monomers from unsaturated substrate averaged only 0.62 mol mol(-1) for the phaz minus strain compared to 0.72 m ... | 2015 | 25563970 |
| toxicity of fungal-generated silver nanoparticles to soil-inhabiting pseudomonas putida kt2440, a rhizospheric bacterium responsible for plant protection and bioremediation. | silver nanoparticles have attracted considerable attention due to their beneficial properties. but toxicity issues associated with them are also rising. the reports in the past suggested health hazards of silver nanoparticles at the cellular, molecular, or whole organismal level in eukaryotes. whereas, there is also need to examine the exposure effects of silver nanoparticle to the microbes, which are beneficial to humans as well as environment. the available literature suggests the harmful effe ... | 2015 | 25562807 |
| widening functional boundaries of the σ(54) promoter pu of pseudomonas putida by defeating extant physiological constraints. | the extant layout of the σ(54) promoter pu, harboured by the catabolic tol plasmid, pww0, of pseudomonas putida is one of the most complex instances of endogenous and exogenous signal integration known in the prokaryotic domain. in this regulatory system, all signal inputs are eventually translated into occupation of the promoter sequence by either of two necessary components: the m-xylene responsive transcriptional factor xylr and the σ(54) containing form of rna polymerase. modelling of these ... | 2015 | 25560994 |
| 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 ... | 2016 | 25556983 |
| effect of trace metals and electron shuttle on simultaneous reduction of reactive black-5 azo dye and hexavalent chromium in liquid medium by pseudomonas sp. | this study demonstrates the role of electron shuttles and trace metals in the biotransformation of azo dye reactive black-5 and hexavalent chromium (crvi) that are released simultaneously in tannery effluent. previously isolated bacterial strain pseudomonas putida ki was used for the simultaneous reduction of the dye (100 mg l(-1)) and crvi (2 mg l(-1)) in a mineral salts medium (msm). among various trace metals, only cu(ii) had a stimulating effect on the bacterial-mediated reduction process. a ... | 2015 | 25556007 |
| genotypic and phenotypic diversity of polyhydroxybutyrate (phb) producing pseudomonas putida isolates of chhattisgarh region and assessment of its phosphate solubilizing ability. | a diverse and versatile spectrum of metabolic activities among isolates of fluorescent pseudomonas putida indicates their adaptability to various niches. these polyhydroxybutyrate producing and phosphate solubilizing isolates showed a high level of functional and genetic versatility among themselves. one of the potential p. putida isolate p132 can contribute as a candidate agent for both biocontrol and pgpr applications. identified as one of the most efficient phb producer and phosphate solubili ... | 2015 | 28324359 |
| removing selected steroid hormones, biocides and pharmaceuticals from water by means of biogenic manganese oxide nanoparticles in situ at ppb levels. | the oxidation of organic micro-pollutants by biogenic manganese oxide nanoparticles (biomnox) has been studied with respect to possible implementation of biomnox in wastewater treatment. for this it would be prerequisite that microbial mn(2+) oxidation and biomnox-driven pollutant removal can occur in situ, i.e. in the same reactor as the removal. here we present the in situ reactivity of biomnox produced by pseudomonas putida towards a range of micro-pollutants at environmentally relevant conce ... | 2015 | 25532770 |
| evaluation of metal biouptake from the analysis of bulk metal depletion kinetics at various cell concentrations: theory and application. | bioavailability of trace metals is a key parameter for assessment of toxicity on living organisms. proper evaluation of metal bioavailability requires monitoring the various interfacial processes that control metal partitioning dynamics at the biointerface, which includes metal transport from solution to cell membrane, adsorption at the biosurface, internalization, and possible excretion. in this work, a methodology is proposed to quantitatively describe the dynamics of cd(ii) uptake by pseudomo ... | 2015 | 25525993 |
| effect of heavy-metal-resistant bacteria on enhanced metal uptake and translocation of the cu-tolerant plant, elsholtzia splendens. | a hydroponics trial was employed to study the effects of pseudomonas putida cz1 (cz1), a heavy-metal-resistant bacterial strain isolated from the rhizosphere of elsholtzia splendens (e. splendens), on the uptake and translocation of copper (cu) in e. splendens. significant promotion of plant growth coupled with the obvious plant-growth-promoting (pgp) characters of the bacteria suggested that cz1 would be a plant-growth-promoting rhizobacterium (pgpr) to e. splendens under cu stress condition. t ... | 2015 | 25510610 |
| fringe-controlled biodegradation under dynamic conditions: quasi 2-d flow-through experiments and reactive-transport modeling. | biodegradation in contaminated aquifers has been shown to be most pronounced at the fringe of contaminant plumes, where mixing of contaminated water and ambient groundwater, containing dissolved electron acceptors, stimulates microbial activity. while physical mixing of contaminant and electron acceptor by transverse dispersion has been shown to be the major bottleneck for biodegradation in steady-state plumes, so far little is known on the effect of flow and transport dynamics (caused, e.g., by ... | 2015 | 25496820 |
| the ppui-rsal-ppur quorum-sensing system regulates cellular motility, pectate lyase activity, and virulence in potato opportunistic pathogen pseudomonas sp. stflb209. | pseudomonas sp. stflb209 was isolated from potato leaf as an n-acylhomoserine lactone (ahl)-producing bacterium and showed a close phylogenetic relationship with p. cichorii, a known plant pathogen. although there are no reports of potato disease caused by pseudomonads in japan, stflb209 was pathogenic to potato leaf. in this study, we reveal the complete genome sequence of stflb209, and show that the strain possesses a ppui-rsal-ppur quorum-sensing system, the sequence of which shares a high si ... | 2015 | 25485871 |
| ner enzymes maintain genome integrity and suppress homologous recombination in the absence of exogenously induced dna damage in pseudomonas putida. | in addition to its prominence in producing genetic diversity in bacterial species, homologous recombination (hr) plays a key role in dna repair and damage tolerance. the frequency of hr depends on several factors, including the efficiency of dna repair systems as hr is involved in recovery of replication forks perturbed by dna damage. nucleotide excision repair (ner) is one of the major dna repair pathways involved in repair of a broad range of dna lesions generally induced by exogenous chemical ... | 2015 | 25463394 |
| integrated micro-biochemical approach for phytoremediation of cadmium and zinc contaminated soils. | the integrated potential of oilcake manure (om), elemental sulphur (s(0)), glomus fasciculatum and pseudomonas putida by growing helianthus annuus l for phytoremediation of cadmium and zinc contaminated soils was investigated under pot experiment. the integrated treatment (2.5 g kg(-1) om, 0.8 g kg(-1) s(0) and co-inoculation with g. fasciculatum and p. putida promoted the dry biomass of the plant. the treatment was feasible for enhanced cadmium accumulation up to 6.56 and 5.25 mg kg(-1) and zin ... | 2015 | 25450919 |
| enhanced 3-methylcatechol production by pseudomonas putida tode1 in a two-phase biotransformation system. | in this study, genetically engineered pseudomonas putida tode1 served as a biocatalyst for the bioproduction of valuable 3-methylcatechol (3mc) from toluene in an aqueous-organic two-phase system. the two-phase system was used as an approach to increase the biocatalyst efficiency. among the organic solvent tested, n-decanol offered several benefits including having the highest partitioning of 3mc, with a high 3mc yield and low cell toxicity. the effect of media supplementation with carbon/energy ... | 2014 | 25420423 |
| singlet oxygen photosensitisation by the fluorescent protein pp2fbfp l30m, a novel derivative of pseudomonas putida flavin-binding pp2fbfp. | flavin-binding fluorescent proteins (fbfps) are a class of fluorescent reporters that have been increasingly used as reporters in the study of cellular structures and dynamics. flavin's intrinsic high singlet oxygen ((1)o2) quantum yield (φδ = 0.51) provides a basis for the development of new fbfp mutants capable of photosensitising (1)o2 for mechanistic and therapeutic applications, as recently exemplified by the fbfp minisog. in the present work we report an investigation on the (1)o2 photopro ... | 2015 | 25375892 |
| formulation of microbial cocktails for btex biodegradation. | btex biodegradation by a mixed community of micro-organisms offers a promising approach in terms of cost-effectiveness and elimination of secondary pollution. two bacterial strains, pseudomonas putida f1 and pseudomonas stutzeri ox1 were chosen to formulate synthetic consortia based on their ability to biodegrade the mono-aromatic compounds. benzene and toluene supported the growth of both the strains; while ethyl benzene and o-xylene were only utilized as growth substrates by p. putida f1 and p ... | 2015 | 25331771 |
| high cell density cultivation of pseudomonas putida kt2440 using glucose without the need for oxygen enriched air supply. | high cell density (hcd) cultivation of bacteria is essential for the majority of industrial processes to achieve high volumetric productivity (g l(-1) h(-1) ) of a bioproduct of interest. this study developed a fed batch bioprocess using glucose as sole carbon and energy source for the hcd of the well described biocatalyst pseudomonas putida kt2440 without the supply of oxygen enriched air. growth kinetics data from batch fermentations were used for building a bioprocess model and designing feed ... | 2015 | 25311981 |
| metabolic engineering of arabidopsis for remediation of different polycyclic aromatic hydrocarbons using a hybrid bacterial dioxygenase complex. | the widespread presence of polycyclic aromatic hydrocarbons (pahs) and their potential harm to various organisms has generated interest in efficiently eliminating these compounds from the environment. phytoremediation is an efficient technology for cleaning up pollutants. however, unlike microorganisms, plants lack the catabolic pathway for complete degradation of these dangerous groups of compounds. one way to enhance the potential of plants for remediation of these compounds is by transferring ... | 2014 | 25305469 |
| coordinated response of phospholipids and acyl components of membrane lipids in pseudomonas putida a (atcc 12633) under stress caused by cationic surfactants. | the present study assessed the role of membrane components of pseudomonas putida a (atcc 12633) under chemical stress conditions originated by treatment with tetradecyltrimethylammonium bromide (ttab), a cationic surfactant. we examined changes in fatty acid composition and in the fluidity of the membranes of cells exposed to ttab at a specific point of growth as well as of cells growing with ttab. the addition of 10-50 mg ttab l(-1) promoted an increase in the saturated/unsaturated fatty acid r ... | 2014 | 25280753 |
| degradation, phytoprotection and phytoremediation of phenanthrene by endophyte pseudomonas putida, pd1. | endophytes have been isolated from a large diversity of plants and have been shown to enhance the remediation efficiency of plants, but little information is available on the influence of endophytic bacteria on phytoremediation of widespread environmental contaminants such as polycyclic aromatic hydrocarbons (pahs). in this study we selected a naturally occurring endophyte for its combined ability to colonize plant roots and degrade phenanthrene in vitro. inoculation of two different willow clon ... | 2014 | 25275224 |
| gibberellin secreting rhizobacterium, pseudomonas putida h-2-3 modulates the hormonal and stress physiology of soybean to improve the plant growth under saline and drought conditions. | the physiological changes in tolerant soybean plants under salt and drought stress conditions with pseudomonas putida h-2-3 were investigated. a bacterial isolate h-2-3 was isolated from soil and identified as pseudomonas putida h-2-3 by 16s rdna sequences. the treatment of p. putida h-2-3 significantly increased the length, fresh and dry weight of shoot and chlorophyll content in gibberellins (gas) deficient mutant waito-c rice seedlings over the control, it might be the presence of ga1, ga4, g ... | 2014 | 25270162 |
| microscopical observation of inhibition-behaviors against diaporthe citri by pre-treated with pseudomonas putida strain thj609-3 on the leaves of citrus plants. | citrus melanose is one of the most important diseases in orchards cultivating citrus in the world. although the disease does not cause yield loss, the profitability of the infected fruits is often reduced in the fresh-market, resulting in economic loss. in this study, disease reduction was proven by pre-treatment with pseudomonas putida strain thj609-3. in order to illustrate mechanism of the disease reduction by the bacterial strain, the infection behaviors of diaporthe citri and necrosis depos ... | 2014 | 25269607 |
| synthetic vanillate-regulated promoter for graded gene expression in sphingomonas. | regulated promoters are an important basic genetic tool allowing, for example, gene-dosage and gene depletion studies. we have previously described a cumate-inducible promoter (p(q5)) that is functional in diverse alphaproteobacteria. this promoter has been engineered by combining a synthetic minimal promoter, p(syn2), and operator sites and the repressor of the pseudomonas putida f1 cym/cmt system. in the present study, we engineered a vanillate-regulated promoter using p(syn2) and the regulato ... | 2014 | 25262659 |
| fis overexpression enhances pseudomonas putida biofilm formation by regulating the ratio of lapa and lapf. | bacteria form biofilm as a response to a number of environmental signals that are mediated by global transcription regulators and alarmones. here we report the involvement of the global transcription regulator fis in pseudomonas putida biofilm formation through regulation of lapa and lapf genes. the major component of p. putida biofilm is proteinaceous and two large adhesive proteins, lapa and lapf, are known to play a key role in its formation. we have previously shown that fis overexpression e ... | 2014 | 25253613 |
| effect of amines as activators on the alcohol-oxidizing activity of pyrroloquinoline quinone-dependent quinoprotein alcohol dehydrogenase. | pyrroloquinoline quinone-dependent quinoprotein alcohol dehydrogenases (pqq-adh) require ammonia or primary amines as activators in in vitro assays with artificial electron acceptors. we found that pqq-adh from pseudomonas putida kt2440 (ppadh) was activated by various primary amines, di-methylamine, and tri-methylamine. the alcohol oxidation activity of ppadh was strongly enhanced and the affinity for substrates was also improved by pentylamine as an activator. | 2014 | 25229857 |
| physical lysis only (plo) methods suitable as rapid sample pretreatment for qpcr assay. | quantitative pcr (qpcr) enables rapid and sensitive gene quantification and is widely used in genomics, such as biological, medical, environmental, and food sciences. however, sample pretreatment requires the use of conventional dna extraction kits which are time-consuming and labor intensive. in this study, we investigated four physical lysis only (plo) methods which are rapid and could serve as alternatives to conventional dna extraction kits. these plo methods are bead mill, heating, sonicati ... | 2014 | 25219535 |
| responses of unsaturated pseudomonas putida cz1 biofilms to environmental stresses in relation to the eps composition and surface morphology. | the extracellular polymeric substance (eps) and surface properties of unsaturated biofilms of a heavy metal-resistant rhizobacterium pseudomonas putida cz1, in response to aging, ph, temperature and osmotic stress, were studied by quantitative analysis of eps and atomic force microscope. it was found that eps production increased approximately linearly with culture time, cells in the air-biofilm interface enhanced eps production and decreased cell volume to cope with nutrient depletion during ag ... | 2014 | 25217027 |
| the potential of the ni-resistant tce-degrading pseudomonas putida w619-tce to reduce phytotoxicity and improve phytoremediation efficiency of poplar cuttings on a ni-tce co-contamination. | to examine the potential of pseudomonas putida w619-tce to improve phytoremediation of ni-tce co-contamination, the effects of inoculation of a ni-resistant, tce-degrading root endophyte on ni-tce phytotoxicity, ni uptake and trichloroethylene (tce) degradation of ni-tce-exposed poplar cuttings are evaluated. after inoculation with p. putida w619-tce, root weight of non-exposed poplar cuttings significantly increased. further, inoculation induced a mitigation of the ni-tce phytotoxicity, which w ... | 2015 | 25174423 |
| analysis of n-acylhomoserine lactone dynamics in continuous cultures of pseudomonas putida isof by use of elisa and uhplc/qtof-ms-derived measurements and mathematical models. | in this interdisciplinary approach, the dynamics of production and degradation of the quorum sensing signal 3-oxo-decanoylhomoserine lactone were studied for continuous cultures of pseudomonas putida isof. the signal concentrations were quantified over time by use of monoclonal antibodies and elisa. the results were verified by use of ultra-high-performance liquid chromatography. by use of a mathematical model we derived quantitative values for non-induced and induced signal production rate per ... | 2014 | 25116602 |
| biocatalytic coatings for air pollution control: a proof of concept study on voc biodegradation. | although biofilm-based biotechnologies exhibit a large potential as solutions for off-gas treatment, the high water content of biofilms often causes pollutant mass transfer limitations, which ultimately limit their widespread application. the present study reports on the proof of concept of the applicability of bioactive latex coatings for air pollution control. toluene vapors served as a model volatile organic compound (voc). the results showed that pseudomonas putida f1 cells could be successf ... | 2015 | 25115963 |
| fed-batch strategies using butyrate for high cell density cultivation of pseudomonas putida and its use as a biocatalyst. | a mathematically based fed-batch bioprocess demonstrated the suitability of using a relatively cheap and renewable substrate (butyric acid) for pseudomonas putida ca-3 high cell density cultivation. butyric acid fine-tuned addition is critical to extend the fermentation run and avoid oxygen consumption while maximising the biomass volumetric productivity. a conservative submaximal growth rate (μ of 0.25 h(-1)) achieved 71.3 g l(-1) of biomass after 42 h of fed-batch growth. when a more ambitious ... | 2014 | 25104034 |
| experimental and kinetic study on the cometabolic biodegradation of phenol and 4-chlorophenol by psychrotrophic pseudomonas putida ly1. | this study investigated the kinetics of phenol and 4-chlorophenol (4-cp) biodegradation by a cold-adapted bacteria, pseudomonas putida ly1, isolated from songhua river sediment. the results showed that p. putida ly1 cannot grow on 4-cp as a sole carbon source. p. putida ly1 had the potential to cometabolic biodegrade phenol and 4-cp in a wide range of temperature (varying from 5 to 35 °c) with the optimal temperature around 25 °c. mixture of phenol and 4-cp were completely removed at two 4-cp co ... | 2015 | 25091164 |
| near-zero growth kinetics of pseudomonas putida deduced from proteomic analysis. | intensive microbial growth typically observed in laboratory rarely occurs in nature. because of severe nutrient deficiency, natural populations exhibit near-zero growth (nzg). there is a long-standing controversy about sustained nzg, specifically whether there is a minimum growth rate below which cells die or whether cells enter a non-growing maintenance state. using chemostat with cell retention (ccr) of pseudomonas putida, we resolve this controversy and show that under nzg conditions, bacteri ... | 2015 | 25088710 |
| comprehensive proteome analysis of the response of pseudomonas putida kt2440 to the flavor compound vanillin. | understanding of the molecular response of bacteria to precursors, products and environmental conditions applied in bioconversions is essential for optimizing whole-cell biocatalysis. to investigate the molecular response of the potential biocatalyst pseudomonas putida kt2440 to the flavor compound vanillin we applied complementary gel- and lc-ms-based quantitative proteomics approaches. our comprehensive proteomics survey included cytoplasmic and membrane proteins and led to the identification ... | 2014 | 25026441 |
| novel and tightly regulated resorcinol and cumate-inducible expression systems for streptomyces and other actinobacteria. | inducible expression is a versatile genetic tool for controlling gene transcription, determining gene functions and other uses. herein, we describe our attempts to create several inducible systems based on a cumate or a resorcinol switch, a hammerhead ribozyme, the laci repressor, and isopropyl β-d-thiogalactopyranoside (iptg). we successfully developed a new cumate (p-isopropylbenzoic acid)-inducible gene switch in actinobacteria that is based on the cymr regulator, the operator sequence (cmt) ... | 2014 | 25012786 |
| screening, identification and culture optimization of a newly isolated aromatic nitrilase-producing bacterium--pseudomonas putida cgmcc3830. | microbial nitrilases have attracted increasing attention in nitrile hydrolysis for carboxylic acid production in recent years. a bacterium with nitrilase activity was isolated and identified as pseudomonas putida cgmcc3830 based on its morphology, physiological and biochemical characteristics, as well as 16s rrna gene sequence. the nitrilase production was optimized by varying culture conditions using the one-factor-at-a-time method and response surface methodology. glycerol 13.54 g/l, tryptone ... | 2014 | 25007577 |
| evaluation of medium-chain-length polyhydroxyalkanoate production by pseudomonas putida ls46 using biodiesel by-product streams. | medium-chain-length polyhydroxyalkanoate (mcl-pha) production by pseudomonas putida ls46 was analyzed in shake-flask-based batch reactions, using pure chemical-grade glycerol (pg), biodiesel-derived "waste" glycerol (wg), and biodiesel-derived "waste" free fatty acids (wfa). cell growth, substrate consumption, mcl-pha accumulation within the cells, and the monomer composition of the synthesized biopolymers were monitored. the patterns of mcl-pha synthesis in p. putida ls46 cells grown on pg and ... | 2014 | 24983445 |
| development of a novel multi-functional active membrane capping barrier for the remediation of nitrobenzene-contaminated sediment. | a novel bio-reactive capping barrier composed of polysulfone/granular activated carbon (ps/gac) hybrid membranes immobilized with microorganism was developed for the remediation of nitrobenzene in sediments. the sem observation demonstrated that all the membranes had a dense top layer and a porous sublayer, this structure can block the transfer of nitrobenzene from sediment to the water and enhance nitrobenzene degradation. adsorption behaviors of nitrobenzene on membranes showed that the membra ... | 2014 | 24929303 |
| electron donation to an archaeal cytochrome p450 is enhanced by pcna-mediated selective complex formation with foreign redox proteins. | cytochrome p450 monooxygenases (p450s) are environmentally friendly biocatalysts that catalyze diverse chemical reactions using molecular oxygen under mild reaction conditions. p450s are activated upon receiving electrons from specific redox partner proteins, although the redox partners for most bacterial/archaeal p450s are not yet identified. thus, it is important to establish a variety of efficient and versatile electron transfer systems from nad(p)h to p450s for the design of biocatalysts. su ... | 2014 | 24924478 |
| aerobic transformation of bde-47 by a pseudomonas putida sp. strain tz-1 isolated from pbdes-contaminated sediment. | a bacterial isolate, tz-1, was isolated from contaminated sediment near electronic waste dismantling workshops, taizhou, china that degraded 2,2',4,4'-tetrabrominated diphenyl ether (bde-47). the isolate was identified as pseudomonas putida sp. with respect to its morphology, biochemical characteristics and 16srdna sequence analysis. tz-1 can use bde-47 as the sole carbon and energy source for growth in mineral salt medium. the isolate degraded bde-47 up to 49.96 % of the initially applied conce ... | 2014 | 24898799 |
| transcriptional and translational control through the 5'-leader region of the dmpr master regulatory gene of phenol metabolism. | expression of pathways for dissimilation of toxic aromatic compounds such as (methyl)phenols interfaces both stress-response and carbon catabolite repression control cascades. in pseudomonas putida, carbon catabolite repression is mediated by the protein crc - a translational repressor that counteracts utilization of less-preferred carbon sources as growth substrates until they are needed. in this work we dissect the regulatory role of the 5'-leader region (5'-lr) of the dmpr gene that encodes t ... | 2015 | 24889314 |
| hyaluronic acid production with corynebacterium glutamicum: effect of media composition on yield and molecular weight. | corynebacterium glutamicum was tested as an alternative host for heterologous production of hyaluronic acid (ha). | 2014 | 24863652 |
| influence of the operon structure on poly(3-hydroxypropionate) synthesis in shimwellia blattae. | glycerol has become a cheap and abundant carbon source due to biodiesel production at a large scale, and it is available for several biotechnological applications. we recently established poly(3-hydroxypropionate) [poly(3hp)] synthesis in a recombinant shimwellia blattae strain (heinrich et al. appl environ microbiol 79:3582-3589, 2013). the major drawbacks of the current strains are (i) low poly(3hp) yields, (ii) low plasmid stability and (iii) insufficient conversion rates. in this study, we d ... | 2014 | 24859521 |
| accurate determination of plasmid copy number of flow-sorted cells using droplet digital pcr. | many biotechnological processes rely on the expression of a plasmid-based target gene. a constant and sufficient number of plasmids per cell is desired for efficient protein production. to date, only a few methods for the determination of plasmid copy number (pcn) are available, and most of them average the pcn of total populations disregarding heterogeneous distributions. here, we utilize the highly precise quantification of dna molecules by droplet digital pcr (ddpcr) and combine it with cell ... | 2014 | 24842041 |
| purification and characterization of carbon-phosphorus bond-cleavage enzyme from glyphosate degrading pseudomonas putida t5. | an inducible, carbon-phosphorus bond-cleavage enzyme was purified from cells of pseudomonas putida t5 grown on n-phosphonomethyl glycine. the native enzyme had a molecular mass of approximately 70 kd and upon sodium dodecyl sulfate polyacrylamide gel electrophoresis (sds-page), yielded a homogeneous protein band with an apparent molecular mass of about 70 kd. activity of purified enzyme was increased by 627-fold compared to the crude extract and showed ph and temperature optima of approximately ... | 2015 | 24840030 |
| effects of biochar-bde-47 interactions on bde-47 bioaccessibility and biodegradation by pseudomonas putida tz-1. | with biochar amendments widely accepted as efficient pops contamination remediation methods, the post-remediation risk assessment and effectiveness evaluation were urgently needed. so in the study, the effects of biochar -2,2',4,4'-tetrabromodiphenyl ether (bde-47) interactions on the bioaccessibility and biodegradation of bde-47 were systematically examined. biodegradation was monitored over 7 day incubation time with strain pseudomonas putida tz-1 and it was revealed that the presence of three ... | 2014 | 24836874 |
| multiple native flavin reductases in camphor-metabolizing pseudomonas putida ncimb 10007: functional interaction with two-component diketocamphane monooxygenase isoenzymes. | although they have been studied for nearly 50 years, the source of the fmnh2 needed for effective biooxidation by the 2,5- and 3,6-diketocamphane monooxygenase (dkcmo) isoenzymes induced by the growth of pseudomonas putida ncimb 10007 (atcc 17453) on camphor remains incompletely characterized. prior studies have focussed exclusively on enzymes present in cells harvested during late-exponential-phase growth despite considerable circumstantial evidence that the flavin reductase (fr) component of t ... | 2014 | 24836624 |
| promoter fusions with optical outputs in individual cells and in populations. | reporter genes are widely used to quantify promoter activity, which controls production of mrna through the interplay with rna polymerases and transcription factors. some of such reporters have either diffuse (lux) or focused (gfp) optical outputs that allow description of transcriptional activity in populations and in single cells. this chapter discusses the use of a dual reporter system gfp-luxcdabe that is placed in broad-host-range plasmids having origins of replication from rk2 and pbbr1. t ... | 2014 | 24818934 |
| the standard european vector architecture (seva) plasmid toolkit. | the standard european vector architecture (seva) toolkit is a simple and powerful resource for constructing optimal plasmid vectors based on a backbone and three interchangeable modules flanked by uncommon restriction sites. functional modules encode several origins of replication, diverse antibiotic selection markers, and a variety of cargoes with different applications. the backbone and dna modules have been minimized and edited for flaws in their sequence and/or functionality. a protocol for ... | 2014 | 24818926 |
| isolation and partial characterization of bacteriophages infecting pseudomonas syringae pv. actinidiae, causal agent of kiwifruit bacterial canker. | the phytopathogen pseudomonas syringae pv. actinidiae (psa) is the causal agent of bacterial canker of kiwifruit. in the last years, it has caused severe economic losses to actinidia spp. cultivations, mainly in italy and new zealand. conventional strategies adopted did not provide adequate control of infection. phage therapy may be a realistic and safe answer to the urgent need for novel antibacterial agents aiming to control this bacterial pathogen. in this study, we described the isolation an ... | 2014 | 24810619 |
| the crc and hfq proteins of pseudomonas putida cooperate in catabolite repression and formation of ribonucleic acid complexes with specific target motifs. | the crc protein is a global regulator that has a key role in catabolite repression and optimization of metabolism in pseudomonads. crc inhibits gene expression post-transcriptionally, preventing translation of mrnas bearing an aanaanaa motif [the catabolite activity (ca) motif] close to the translation start site. although crc was initially believed to bind rna by itself, this idea was recently challenged by results suggesting that a protein co-purifying with crc, presumably the hfq protein, cou ... | 2015 | 24803210 |
| effect of silver nanoparticles and silver ions on growth and adaptive response mechanisms of pseudomonas putida mt-2. | the distribution and use of nanoparticles increased rapidly during the last years, while the knowledge about mode of action, ecological tolerance and biodegradability of these chemicals is still insufficient. the effect of silver nanoparticles (agnp) and free silver ions (ag(+) , agno3 ) on pseudomonas putida mt-2 as one of the best described bacterial strains for stress response were investigated. the effective concentration (ec50) causing 50% growth inhibition for agnp was about 250 mg l(-1) , ... | 2014 | 24801753 |
| from the phosphoenolpyruvate phosphotransferase system to selfish metabolism: a story retraced in pseudomonas putida. | although dna is the ultimate repository of biological information, deployment of its instructions is constrained by the metabolic and physiological status of the cell. to this end, bacteria have evolved intricate devices that connect exogenous signals (e.g. nutrients, physicochemical conditions) with endogenous conditions (metabolic fluxes, biochemical networks) that coordinately influence expression or performance of a large number of cellular functions. the phosphoenolpyruvate:carbohydrate-pho ... | 2014 | 24801646 |
| coselection for resistance to multiple late-generation human therapeutic antibiotics encoded on tetracycline resistance plasmids captured from uncultivated stream and soil bacteria. | transmissible plasmids captured from stream and soil bacteria conferring resistance to tetracycline in pseudomonas were evaluated for linked resistance to antibiotics used in the treatment of human infections. | 2014 | 24797476 |
| abatement of styrene waste gas emission by biofilter and biotrickling filter: comparison of packing materials and inoculation procedures. | the removal of styrene was studied using two biofilters packed with peat and coconut fibre (bf1-p and bf2-c, respectively) and one biotrickling filter (btf) packed with plastic rings. two inoculation procedures were applied: an enriched culture with strain pseudomonas putida cect 324 for bfs and activated sludge from a municipal wastewater treatment plant for the btf. inlet loads (ils) between 10 and 45 g m(-3) h(-1) and empty bed residence times (ebrts) from 30 to 120 s were applied. at inlet c ... | 2015 | 24797312 |
| identification and characterization of an acyl-coa dehydrogenase from pseudomonas putida kt2440 that shows preference towards medium to long chain length fatty acids. | diverse and elaborate pathways for nutrient utilization, as well as mechanisms to combat unfavourable nutrient conditions make pseudomonas putida kt2440 a versatile micro-organism able to occupy a range of ecological niches. the fatty acid degradation pathway of p. putida is complex and correlated with biopolymer medium chain length polyhydroxyalkanoate (mcl-pha) biosynthesis. little is known about the second step of fatty acid degradation (β-oxidation) in this strain. in silico analysis of its ... | 2014 | 24794972 |
| temporary removal: optimization of recombinant pseudomonas putida proline dehydrogenase purification in aqueous two-phase systems using response surface methodology. | the publisher regrets that this article has been temporarily removed. a replacement will appear as soon as possible in which the reason for the removal of the article will be specified, or the article will be reinstated. the full elsevier policy on article withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy. | 2014 | 24794501 |
| structural basis for the substrate specificity and the absence of dehalogenation activity in 2-chloromuconate cycloisomerase from rhodococcus opacus 1cp. | 2-chloromuconate cycloisomerase from the gram-positive bacterium rhodococcus opacus 1cp (rho-2-cmci) is an enzyme of a modified ortho-pathway, in which 2-chlorophenol is degraded using 3-chlorocatechol as the central intermediate. in general, the chloromuconate cycloisomerases catalyze not only the cycloisomerization, but also the process of dehalogenation of the chloromuconate to dienelactone. however rho-2-cmci, unlike the homologous enzymes from the gram-negative bacteria, is very specific fo ... | 2014 | 24768773 |
| freeing pseudomonas putida kt2440 of its proviral load strengthens endurance to environmental stresses. | 2.6% of the genome of the soil bacterium pseudomonas putida kt2440 encodes phage-related functions, but the burden of such opportunistic dna on the host physiology is unknown. each of the four apparently complete prophages borne by this strain was tested for stability, spontaneous excision and ability to cause lysis under various stressing conditions. while prophages p3 (pp2266-pp2297) and p4 (pp1532-1584) were discharged from the genome at a detectable rate, their induction failed otherwise to ... | 2015 | 24762028 |
| effect of red clay on diesel bioremediation and soil bacterial community. | red clay is a type of soil, the red color of which results from the presence of iron oxide. it is considered an eco-friendly material, with many industrial, cosmetic, and architectural uses. a patented method was applied to red clay in order to change its chemical composition and mineral bioavailability. the resulting product was designated processed red clay. this study evaluates the novel use of red clay and processed red clay as biostimulation agents in diesel-contaminated soils. diesel biode ... | 2014 | 24743885 |
| pumping iron to keep fit: modulation of siderophore secretion helps efficient aromatic utilization in pseudomonas putida kt2440. | studies of biotechnology applications of pseudomonas putida kt2440 have been predominantly focused on regulation and expression of the toluene degradation (tol) pathway. unfortunately, there is limited information on the role of other physiological factors influencing aromatic utilization. in this report, we demonstrate that p. putida kt2440 increases its siderophore secretion in response to the availability of benzyl alcohol, a model aromatic substrate. it is argued that accelerated siderophore ... | 2014 | 24742959 |
| the effect of fish and card-fish on the isotopic composition of (13)c- and (15)n-labeled pseudomonas putida cells measured by nanosims. | the use of nanosims for the exploration of microbial activities in natural habitats often implies that stable isotope tracer experiments are combined with in situ hybridization techniques (i.e. fluorescence in situ hybridization (fish) or catalyzed reporter deposition (card)-fish). in this study, pseudomonas putida grown on (13)c- and (15)n-labeled carbon and nitrogen, collected in exponential growth and stationary phases, was hybridized and analyzed by nanosims. it was shown that (13)c and (15) ... | 2014 | 24702905 |
| enhancement of thermo-stability and product tolerance of pseudomonas putida nitrile hydratase by fusing with self-assembling peptide. | self-assembling amphipathic peptides (saps) are the peptides that can spontaneously assemble into ordered nanostructures. it has been reported that the attachment of saps to the n- or c-terminus of an enzyme can benefit the thermo-stability of the enzyme. here, we discovered that the thermo-stability and product tolerance of nitrile hydratase (nhase) were enhanced by fusing with two of the saps (eak16 and elk16). when the elk16 was fused to the n-terminus of β-subunit, the resultant nhase (sap-n ... | 2014 | 24698299 |
| simultaneous removal of phenol, cu and cd from water with corn cob silica-alginate beads. | phenol and heavy metals in petroleum waste are environmental and human health concerns, but physicochemical removal is often cost-prohibitive and can produce toxic secondary products and treatment residues. an environmentally benign alternative combines corn cob silica with alginate and immobilized bacteria into beads for treating contaminated water. the concentration of phenol was decreased >92% by pseudomonas putida yns1 on aliginate-silica beads (2%, w/v) after equilibrating for 96h with wate ... | 2014 | 24685529 |
| crystal structures of pseudomonas putida esterase reveal the functional role of residues 187 and 287 in substrate binding and chiral recognition. | a recombinant carboxylesterase (rppe) from pseudomonas putida ecu1011 was previously cloned and engineered to give a potential application for resolving chiral α-hydroxy acids including mandelic acids and derivatives. two variants rppew187h and rpped287a showed a ∼100-fold increase in activity towards rac-2-acetoxy-2-(2'-chlorophenyl) acetate (rac-aco-cpa), but rpped287a had a significant decrease in enantioselectivity (e=8.7) compared to rppew187h and the wild-type rppe (rppewt) (e>200). here w ... | 2014 | 24680822 |
| effect of external voltage on pseudomonas putida f1 in a bio electrochemical cell using toluene as sole carbon and energy source. | | 2014 | 24677363 |
| liquid chromatography time of flight mass spectrometry based environmental metabolomics for the analysis of pseudomonas putida bacteria in potable water. | water supply biofilms have the potential to harbour waterborne diseases, accelerate corrosion, and contribute to the formation of tuberculation in metallic pipes. one particular species of bacteria known to be found in the water supply networks is pseudomonas sp., with the presence of pseudomonas putida being isolated to iron pipe tubercles. current methods for detecting and analysis pipe biofilms are time consuming and expensive. the application of metabolomics techniques could provide an alter ... | 2014 | 24674937 |
| functional coexistence of twin arsenic resistance systems in pseudomonas putida kt2440. | the genome of the soil bacterium pseudomonas putida kt2440 bears two virtually identical arsrbch operons putatively encoding resistance to inorganic arsenic species. single and double chromosomal deletions in each of these ars clusters of this bacterium were tested for arsenic sensitivity and found that the contribution of each operon to the resistance to the metalloid was not additive, as either cluster sufficed to endow cells with high-level resistance. however, otherwise identical traits link ... | 2015 | 24673935 |
| identification, cloning and biochemical characterization of pseudomonas putida a (atcc 12633) monooxygenase enzyme necessary for the metabolism of tetradecyltrimethylammonium bromide. | this study presents the first report of the purification and characterization of a monooxygenase enzyme from pseudomonas putida a (atcc 12633) that is responsible for the oxidation of physiologically relevant quaternary ammonium compounds, the tetradecyltrimethylammonium bromide. the degradation of tetradecyltrimethylammonium bromide by p. putida a (atcc 12633) is initiated by n-dealkylation and catalysed by tetradecyltrimethylammonium monooxygenase (ttabmo), resulting in the formation of tetrad ... | 2014 | 24664234 |
| toxicity of differently sized and coated silver nanoparticles to the bacterium pseudomonas putida: risks for the aquatic environment? | aim of this study was to describe the toxicity of a set of different commercially available silver nanoparticles (agnps) to the gram-negative bacterium pseudomonas putida (growth inhibition assay, iso 10712) in order to contribute to their environmental hazard and risk assessment. different agnp sizes and coatings were selected in order to analyze whether those characteristics are determinants of nanoparticle toxicity. silver nitrate was tested for comparison. in general pseudomonas putida react ... | 2014 | 24659347 |
| structural and mechanistic insight into alkane hydroxylation by pseudomonas putida alkb. | pseudomonas putida gpo1 alkane hydroxylase (alkb) is an integral membrane protein that catalyses the hydroxylation of medium-chain alkanes (c3-c12). 1-octyne irreversibly inhibits this non-haem di-iron mono-oxygenase under turnover conditions, suggesting that it acts as a mechanism-based inactivator. upon binding to the active site, 1-octyne is postulated to be oxidized to an oxirene that rapidly rearranges to a reactive ketene which covalently acylates nearby residues, resulting in enzyme inact ... | 2014 | 24646189 |
| degradation of polyurethane by bacterium isolated from soil and assessment of polyurethanolytic activity of a pseudomonas putida strain. | the increasing usage and the persistence of polyester polyurethane (pu) generate significant sources of environmental pollution. the effective and environmental friendly bioremediation techniques for this refractory waste are in high demand. in this study, three novel pu degrading bacteria were isolated from farm soils and activated sludge. based upon 16s ribosomal rna gene sequence blast, their identities were determined. particularly robust activity was observed in pseudomonas putida; it spent ... | 2014 | 24633845 |
| identification of novel polyphenolic inhibitors of shikimate dehydrogenase (aroe). | shikimate dehydrogenase (aroe) is an attractive target for herbicides and antimicrobial agents due to its conserved and essential nature in plants, fungi, and bacteria. here, we have performed an in vitro screen using a collection of more than 5500 compounds and identified 24 novel inhibitors of aroe from pseudomonas putida the ic50 values for the two most potent inhibitors we identified, epigallocatechin gallate (egcg) and epicatechin gallate (ecg), were 3.0 ± 0.2 µm and 3.7 ± 0.5 µm, respectiv ... | 2014 | 24632659 |
| the differential response of the pben promoter of pseudomonas putida mt-2 to benr and xyls prevents metabolic conflicts in m-xylene biodegradation. | pseudomonas putida mt-2 encompasses two alternative and potentially conflicting routes for benzoate metabolism, one meta pathway encoded by xyl genes of the pww0 plasmid and mastered by the pm promoter and xyls, and one chromosomally encoded ortho pathway initiated by pben and the benr protein. any cross-activation of pben promoter by xyls ought to cause a metabolic conflict during the degradation of m-xylene because 3-methylbenzoate (3mbz) generated as an intermediate can be channelled through ... | 2015 | 24588992 |
| effect of peg-mediated pore forming on ca-alginate immobilization of nitrilase-producing bacteria pseudomonas putida xy4. | effect of peg-mediated pore forming on ca-alginate immobilization of nitrilase-producing bacteria pseudomonas putida xy4 was studied. through using peg as porogen, the environmental tolerance as well as the biocatalytic reaction efficiency of immobilized cells was greatly improved, i.e., ca-alginate-peg immobilized cells got better temperature and substrate concentration tolerance than ca-alginate immobilized cells and showed similar efficiency with free cells, suggesting that the intrinsic mass ... | 2014 | 24573215 |
| a demonstration of biofiltration for voc removal in petrochemical industries. | a biotrickling filter demo has been set up in a petrochemical factory in sinopec group for about 10 months with a maximum inlet gas flow rate of 3000 m3 h(-1). the purpose of this project is to assess the ability of the biotrickling filter to remove hardly biodegradable vocs such as benzene, toluene and xylene which are recalcitrant and poorly water soluble and commonly found in petrochemical factories. light-weight hollow ceramic balls (φ 5-8 cm) were used as the packing media treated with larg ... | 2014 | 24569855 |
| critical residues of class ii pha synthase for expanding the substrate specificity and enhancing the biosynthesis of polyhydroxyalkanoate. | this study describes protein model of type ii pseudomonas putida gpo1 synthase (phac1(pp)) and using single or multiple points mutagenesis to identify the beneficial amino acid residues that change the pha accumulation and the substrate chain-length specificity of type ii pha synthase. the p. putida gpp104 pha⁻ was used as a host for evaluating the substrate specificity and pha yield of the mutated phac1(pp). the evolved phac1(pp) were coexpressed with β-ketothiolase (phba(re)) and the acetoacet ... | 2014 | 24564904 |
| homology modeling and function of trehalose synthase from pseudomonas putida p06. | trehalose is a non-reducing disaccharide that has wide applications in the food industry and pharmaceutical manufacturing. trehalose synthase (tres) from pseudomonas putida p06 catalyzes the reversible interconversion of maltose and trehalose and may have applications in the food industry. however, the catalytic mechanism of tres is not well understood. here, we investigated the structural characteristics of this enzyme by homology modeling. the highly conserved asp294 residue was identified to ... | 2014 | 24563286 |
| identification of the specific electron transfer proteins, ferredoxin, and ferredoxin reductase, for cyp105d7 in streptomyces avermitilis ma4680. | it was previously proposed that regiospecific hydroxylation of daidzein at 3'-position is mediated by cytochrome p450 hydroxylase (cyp105d7) in the presence of putidaredoxin (camb) and putidaredoxin reductase (cama) as electron transfer proteins from pseudomonas putida. the genome sequence of streptomyces avermitilis ma4680 revealed 33 p450 (cyps) with 6 ferredoxin reductases (fprs) and 9 ferredoxins (fdxs) as their putative electron transfer partner proteins. to identify right endogenous electr ... | 2014 | 24549766 |
| simulated sugar factory wastewater remediation kinetics using algal-bacterial raceway reactor promoted by polyacrylate polyalcohol. | the remediation kinetics of simulated sugar factory wastewater (sfw) using an algal-bacterial culture (abc) of chlorella vulgaris in association with pseudomonas putida in a raceway reactor was found to be enhanced by 89% with the addition of 80ppm of copolymer polyacrylate polyalcohol (papa). this was achieved by efficient suspension of the abc throughout the water body maintaining optimum ph and dissolved oxygen that led to rapid cod removal and improved algal biomass production. the suspensio ... | 2014 | 24530948 |
| support vector regression model of wastewater bioreactor performance using microbial community diversity indices: effect of stress and bioaugmentation. | the relationship between microbial community structure and function has been examined in detail in natural and engineered environments, but little work has been done on using microbial community information to predict function. we processed microbial community and operational data from controlled experiments with bench-scale bioreactor systems to predict reactor process performance. four membrane-operated sequencing batch reactors treating synthetic wastewater were operated in two experiments to ... | 2014 | 24530548 |
| microbial community analysis in biotrickling filters treating isopropanol air emissions. | the evolution of the microbial community was analysed over one year in two biotrickling filters operating under intermittent feeding conditions and treating isopropanol emissions, a pollutant typically found in the flexography sector. each reactor was packed with one media: plastic cross-flow-structured material or polypropylene rings. the communities were monitored by fluorescence in situ hybridization (fish) and denaturing gradient gel electrophoresis (dgge) analysis of the 16s rrna region. af ... | 2014 | 24527643 |
| polyhydroxyalkanoate synthesis affects biosurfactant production and cell attachment to hydrocarbons in pseudomonas sp. ka-08. | stressful conditions prevailing in hydrocarbon-contaminated sites influence the diversity, distribution, and activities of microorganisms. oil bioremediation agents should develop special characteristics to cope with these environments like surfactant production and cellular affinity to hydrocarbons. additionally, polyhydroxyalkanoate (pha) accumulation was proven to improve tolerance to stressful conditions. pseudomonas sp. ka-08 was isolated from a chronic oil-contaminated environment, it is h ... | 2014 | 24519857 |
| genetic evidence of a high-affinity cyanuric acid transport system in pseudomonas sp. adp. | the pseudomonas sp. adp plasmid padp-1 encodes the activities involved in the hydrolytic degradation of the s-triazine herbicide atrazine. here, we explore the presence of a specific transport system for the central intermediate of the atrazine utilization pathway, cyanuric acid, in pseudomonas sp. adp. growth in fed-batch cultures containing limiting cyanuric acid concentrations is consistent with high-affinity transport of this substrate. acquisition of the ability to grow at low cyanuric acid ... | 2014 | 24484197 |
| potent inhibition of mandelate racemase by a fluorinated substrate-product analogue with a novel binding mode. | mandelate racemase (mr) from pseudomonas putida catalyzes the mg(2+)-dependent 1,1-proton transfer that interconverts the enantiomers of mandelate. because trifluorolactate is also a substrate of mr, we anticipated that replacing the phenyl rings of the competitive, substrate-product analogue inhibitor benzilate (ki = 0.7 mm) with trifluoromethyl groups might furnish an inhibitor. surprisingly, the substrate-product analogue 3,3,3-trifluoro-2-hydroxy-2-(trifluoromethyl)propanoate (tfhtp) was a p ... | 2014 | 24472022 |
| an unusual repressor controls the expression of a crucial nicotine-degrading gene cluster in pseudomonas putida s16. | transcriptional factors that contain helix-turn-helix (hth) dna-binding domains are widespread in bacteria for regulating gene expression on demand, and function as homodimers that bind a palindromic dna segment. here, we show that an hth-containing transcriptional regulator, nicr2, in pseudomonas putida s16 plays a critical role in controlling the expression of a crucial gene cluster (nic2) in nicotine degradation, and nicr2 binds dna in a manner different from most other dna-binding proteins t ... | 2014 | 24471758 |