Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| arthrobacter siccitolerans sp. nov., a highly desiccation-tolerant, xeroprotectant-producing strain isolated from dry soil. | a novel desiccation-tolerant, xeroprotectant-producing bacterium, designated strain 4j27(t), was isolated from a nerium oleander rhizosphere subjected to seasonal drought in granada, spain. phylogenetic analysis based on 16s rrna gene sequencing placed the isolate within the genus arthrobacter, its closest relative being arthrobacter phenanthrenivorans shep3 dsm 18606(t), with which it showed 99.23 % 16s rrna gene sequence similarity. dna-dna hybridization measurements showed less than 25 % rela ... | 2013 | 23771623 |
| cooperativity and interaction energy threshold effects in recognition of the -10 promoter element by bacterial rna polymerase. | rna polymerase (rnap) melts promoter dna to form transcription-competent open promoter complex (rpo). interaction of the rnap σ subunit with non-template strand bases of a conserved -10 element (consensus sequence t-12a-11t-10a-9a-8t-7) is an important source of energy-driving localized promoter melting. here, we used an rnap molecular beacon assay to investigate interdependencies of rnap interactions with -10 element nucleotides. the results reveal a strong cooperation between rnap interactions ... | 2013 | 23771146 |
| isolation and genetic characterization of an improved benzene-tolerant mutant of pseudomonas putida s12. | pseudomonas putida s12.49, a mutant stain of p. putida s12 that tolerates up to 20 mm benzene, was obtained by evolutionary selection. the genetic basis for the strongly enhanced benzene tolerance was investigated by proteome and transcriptome analysis. indications were found that the highly benzene-tolerant phenotype is the resultant of multi-level systemic changes. the solvent extrusion pump srpabc was constitutively expressed in p. putida s12.49, which could be attributed to the disruption of ... | 2010 | 23766120 |
| functional analysis of new transporters involved in stress tolerance in pseudomonas putida dot-t1e. | pseudomonas putida dot-t1e is a highly solvent-tolerant strain. although the main mechanism that confers solvent tolerance to the strain is the ttgghi efflux pump, a number of other proteins are also involved in the response to toluene. previous proteomic and transcriptomic analysis carried out in our lab with p. putida dot-t1e, and the solvent-sensitive strain, p. putida kt2440, revealed several transporters that were induced in the presence of toluene. we prepared five mutants of the correspon ... | 2010 | 23766111 |
| pseudomonas putida kt2440 causes induced systemic resistance and changes in arabidopsis root exudation. | pseudomonas putida kt2440 is an efficient colonizer of the rhizosphere of plants of agronomical and basic interest. we have demonstrated that kt2440 can protect the model plant arabidopsis thaliana against infection by the phytopathogen pseudomonas syringae pv. tomato dc3000. p. putida extracellular haem-peroxidase (pp2561) was found to be important for competitive colonization and essential for the induction of plant systemic resistance. root exudates of plants elicited by kt2440 exhibited dist ... | 2010 | 23766110 |
| physiological and transcriptomic characterization of a flia mutant of pseudomonas putida kt2440. | pseudomonas putida kt2440 encodes 23 alternative sigma factors. the flia gene, which encodes σ(28) , is in a cluster with other genes involved in flagella biosynthesis and chemotaxis. reverse transcriptase-pcr revealed that this cluster is comprised of four independent transcriptional units: flhaf, flenflia, cheyza and chebmotab. we generated a nonpolar flia mutant by homologous recombination and tested its motility, adhesion to biotic and abiotic surfaces, and responses to various stress condit ... | 2010 | 23766109 |
| a general profile for the merr family of transcriptional regulators constructed using the semi-automated provalidator tool. | provalidator is a web-based tool that facilitates the design and validation of generalized profiles of protein families in prokaryotes. this tool combines the nearly full automation of profile building with a search for family members in all available databases. the tool is useful for assigning a given protein to a specific family, and is also useful for genome mining in annotated prokaryotic genomes. the tool is freely available at http://www.bactregulators.org. as proof of concept we construct ... | 2009 | 23765930 |
| in vivo role of fdhd and fdme in formate metabolism in pseudomonas putida: redundancy and expression in the stationary phase. | in pseudomonas putida two open reading frames (orfs) pp0257 and pp0492 were originally annotated as accessory formate dehydrogenase proteins. the orf pp0492 (fdmd) is at the 3' end of the orf pp0489 through pp0491 operon that encodes one of the formate dehydrogenases of p. putida and it is transcribed with this operon preferentially at the stationary phase. the orf pp0257 (fdhd) is unlinked to formate dehydrogenase clusters and, as to multi-component formate dehydrogenases, pp0257 is also prefer ... | 2009 | 23765795 |
| a metagenomic study highlights phylogenetic proximity of quorum-quenching and xenobiotic-degrading amidases of the as-family. | quorum-sensing (qs) signals of the n-acylhomoserine lactone (nahl) class are cleaved by quorum-quenching enzymes, collectively named nahlases. here, functional metagenomics allowed the discovery of a novel bacterial nahlase in a rhizosphere that was treated with γ-caprolactone. as revealed by rrs-dgge and rrs-pyrosequencing, this treatment increased the percentage of the nahl-degrading bacteria and strongly biased the structure of the bacterial community, among which azospirillum dominated. amon ... | 2013 | 23762380 |
| mycobacterium tuberculosis rv3406 is a type ii alkyl sulfatase capable of sulfate scavenging. | the genome of mycobacterium tuberculosis (mtb) encodes nine putative sulfatases, none of which have a known function or substrate. here, we characterize mtb's single putative type ii sulfatase, rv3406, as a non-heme iron (ii) and α-ketoglutarate-dependent dioxygenase that catalyzes the oxidation and subsequent cleavage of alkyl sulfate esters. rv3406 was identified based on its homology to the alkyl sulfatase atsk from pseudomonas putida. using an in vitro biochemical assay, we confirmed that rv ... | 2013 | 23762287 |
| bacterial tactic response to silver nanoparticles. | in this study, we investigated the tactic response of pseudomonas putida g7, a representative soil bacterium, towards silver nanoparticles (agnps). the study integrated the characterization of surface area and size distribution of agnps, toxicity determinations, based on atp production, and assessment of the repellent reaction by means of an inverted capillary assay ('chemical-in-pond' method), and changes in the motility behaviour determined by computer-assisted motion analysis. our data demons ... | 2011 | 23761331 |
| growth of pseudomonas putida at low temperature: global transcriptomic and proteomic analyses. | in its natural habitats (soil, water and rhizosphere), pseudomonas putida can suffer frequent and long-term changes in temperature that affect its growth and survival. pseudomonas putida kt2440, a well-characterized model strain, grows optimally at 30°c but can proliferate at temperatures as low as 4°c. however, little information is available on the physiological changes that occur when p. putida grows at low temperatures. to investigate this area, the transcriptome and proteome profiles of cel ... | 2011 | 23761279 |
| ppor, an orphan luxr-family protein of pseudomonas putida kt2440, modulates competitive fitness and surface motility independently of n-acylhomoserine lactones. | pseudomonas putida kt2440 does not produce any of the common molecules involved in quorum sensing signalling described in other bacteria. however, as is the case in other microorganisms, the genome of this strain contains an open reading frame (pp_4647) coding for a transcriptional regulator belonging to the luxr protein family. in this article, we present evidence indicating that this protein, named ppor, modulates swarming motility in kt2440 and plays a role in the survival of this strain in t ... | 2011 | 23761234 |
| fatty acid-mediated signalling between two pseudomonas species. | we report the identification of fatty acids as mediators of intercellular signalling in pseudomonas putida, and between pseudomonas aeruginosa and p. putida. tetradecanoic acid and fatty acids of similar chain length are present in supernatants of these strains and activate population density-dependent expression of ddca, a gene involved in corn seed and root colonization by p. putida kt2440. consistently, significant amounts of these compounds were also found in corn root exudates. the signalli ... | 2012 | 23760827 |
| plant lectin-like antibacterial proteins from phytopathogens pseudomonas syringae and xanthomonas citri. | the genomes of pseudomonas syringae pv. syringae 642 and xanthomonas citri pv. malvacearum lmg 761 each carry a putative homologue of the plant lectin-like bacteriocin (llpa) genes previously identified in the rhizosphere isolate pseudomonas putida bw11m1 and the biocontrol strain pseudomonas fluorescens pf-5. the respective purified recombinant proteins, llpapss642 and llpaxcm761 , display genus-specific antibacterial activity across species boundaries. the inhibitory spectrum of the p. syringa ... | 2012 | 23760822 |
| light regulation of swarming motility in pseudomonas syringae integrates signaling pathways mediated by a bacteriophytochrome and a lov protein. | the biological and regulatory roles of photosensory proteins are poorly understood for nonphotosynthetic bacteria. the foliar bacterial pathogen pseudomonas syringae has three photosensory protein-encoding genes that are predicted to encode the blue-light-sensing lov (light, oxygen, or voltage) histidine kinase (lov-hk) and two red/far-red-light-sensing bacteriophytochromes, bphp1 and bphp2. we provide evidence that lov-hk and bphp1 form an integrated network that regulates swarming motility in ... | 2013 | 23760465 |
| two novel piwi families: roles in inter-genomic conflicts in bacteria and mediator-dependent modulation of transcription in eukaryotes. | the piwi module, found in the piwi/ago superfamily of proteins, is a critical component of several cellular pathways including germline maintenance, chromatin organization, regulation of splicing, rna interference, and virus suppression. it binds a guide strand which helps it target complementary nucleic strands. | 2013 | 23758928 |
| evolution of rep diversity: a comparative study. | repetitive extragenic palindromic elements (reps) constitute a group of bacterial genomic repeats known for their high abundance and several roles in host cells´ physiology. we analyzed the phylogenetic distribution of particular rep classes in genomic sequences of sixty-three bacterial strains belonging to the pseudomonas fluorescens species complex and ten strains of stenotrophomonas sp., in order to assess intraspecific rep diversity and to gain insight into long-term rep evolution. | 2013 | 23758774 |
| transcriptional control of the main aromatic hydrocarbon efflux pump in pseudomonas. | bacteria of the species pseudomonas putida are ubiquitous soil inhabitants, and a few strains are able to thrive in the presence of extremely high concentrations of toxic solvents such as toluene and related aromatic hydrocarbons. toluene tolerance is multifactorial in the sense that bacteria use a wide range of physiological and genetic changes to overcome solvent damage. this includes enhanced membrane impermeabilization through cis to trans isomerization of unsaturated fatty acids, activation ... | 2012 | 23757269 |
| distinct lipopeptide production systems for wlip (white line-inducing principle) in pseudomonas fluorescens and pseudomonas putida. | the interaction of wlip (white line-inducing principle), a member of the viscosin group of pseudomonas lipopeptides, with tolaasin, a lipopeptide mycotoxin secreted by pseudomonas tolaasii, enables identification of the mushroom pathogen relying on formation of a lipopeptide coprecipitate between confronted colonies of an indicator strain (designated pseudomonas 'reactans') and p. tolaasii. the wlip non-ribosomal lipopeptide synthesis system of the mushroom isolate p. 'reactans' lmg 5329 (wip) w ... | 2012 | 23757145 |
| pectin methylesterase and pectin remodelling differ in the fibre walls of two gossypium species with very different fibre properties. | pectin, a major component of the primary cell walls of dicot plants, is synthesized in golgi, secreted into the wall as methylesters and subsequently de-esterified by pectin methylesterase (pme). pectin remodelling by pmes is known to be important in regulating cell expansion in plants, but has been poorly studied in cotton. in this study, genome-wide analysis showed that pmes are a large multi-gene family (81 genes) in diploid cotton (gossypium raimondii), an expansion over the 66 in arabidopsi ... | 2013 | 23755181 |
| shigella ipah0722 e3 ubiquitin ligase effector targets traf2 to inhibit pkc-nf-κb activity in invaded epithelial cells. | nf-κb plays a central role in modulating innate immune responses to bacterial infections. therefore, many bacterial pathogens deploy multiple mechanisms to counteract nf-κb activation. the invasion of and subsequent replication of shigella within epithelial cells is recognized by various pathogen recognition receptors as pathogen-associated molecular patterns. these receptors trigger innate defense mechanisms via the activation of the nf-κb signaling pathway. here, we show the inhibition of the ... | 2013 | 23754945 |
| amphipatic molecules affect the kinetic profile of pseudomonas putida chlorocatechol 1,2-dioxygenase. | dioxygenases are nonheme iron enzymes that biodegrade recalcitrant compounds, such as catechol and derivatives, released into the environment by modern industry. intradiol dioxygenases have attracted much attention due to the interest in their use for bioremediation, which has demanded efforts towards understanding their action mechanism and also how to control it. the role of unexpected amphipatic molecules, observed in crystal structures of intradiol dioxygenases, during catalysis has been poo ... | 2013 | 23754625 |
| optimized enzymatic dual functions of paprx protein by proton irradiation. | we investigated the effects of proton irradiation on the function and structure of the pseudomonas aeruginosa peroxiredoxin (paprx). polyacrylamide gel demonstrated that paprx proteins exposed to proton irradiation at several doses exhibited simultaneous formation of high molecular weight (hmw) complexes and fragmentation. size-exclusion chromatography (sec) analysis revealed that the number of fragments and very low molecular weight (lmw) structures increased as the proton irradiation dose incr ... | 2013 | 23753570 |
| optimized enzymatic dual functions of paprx protein by proton irradiation. | we investigated the effects of proton irradiation on the function and structure of the pseudomonas aeruginosa peroxiredoxin (paprx). polyacrylamide gel demonstrated that paprx proteins exposed to proton irradiation at several doses exhibited simultaneous formation of high molecular weight (hmw) complexes and fragmentation. size-exclusion chromatography (sec) analysis revealed that the number of fragments and very low molecular weight (lmw) structures increased as the proton irradiation dose incr ... | 2013 | 23753570 |
| identification and characterization of biosurfactants produced by the arctic bacterium pseudomonas putida bd2. | one hundred and thirty bacterial strains, isolated from arctic soil on the svalbard archipelago, were screened for biosurfactant production. among them, an isolate identified as pseudomonas putida bd2 was selected as a potential biosurfactant-producer based on the surface/interfacial activity of the culture supernatant. the ability of the strain to produce simultaneously phosphatidylethanolamines and rhamnolipid, using glucose as a sole carbon source, was demonstrated. the rhamnolipid rha-rha-c1 ... | 2013 | 23751417 |
| a lethal case of pseudomonas putida bacteremia due to soft tissue infection. | pseudomonas putida is an uncommon cause of skin and soft tissue infections. it is often associated with trauma or immunocompromised state. we present the first lethal case of bacteremia due to skin and soft tissue infections, which had malnutrition, immobility, and peripheral vascular disease as risk factors. | 2013 | 23750097 |
| regulation of the ald gene encoding alanine dehydrogenase by aldr in mycobacterium smegmatis. | the regulatory gene aldr was identified 95 bp upstream of the ald gene encoding l-alanine dehydrogenase in mycobacterium smegmatis. the aldr protein shows sequence similarity to the regulatory proteins of the lrp/asnc family. using an aldr deletion mutant, we demonstrated that aldr serves as both activator and repressor for the regulation of ald gene expression, depending on the presence or absence of l-alanine. the purified aldr protein exists as a homodimer in the absence of l-alanine, while i ... | 2013 | 23749971 |
| engineered escherichia coli for short-chain-length medium-chain-length polyhydroxyalkanoate copolymer biosynthesis from glycerol and dodecanoate. | short-chain-length medium-chain-length polyhydroxyalkanoate (scl-mcl pha) copolymers are promising as bio-plastics with properties ranging from thermoplastics to elastomers. in this study, the hybrid pathway for the biosynthesis of scl-mcl pha copolymers was established in recombinant escherichia coli by co-expression of β-ketothiolase (phaare) and nadph-dependent acetoacetyl-coa reductase (phabre) from ralstonia eutropha together with pha synthases from r. eutropha (phacre), aeromonas hydrophil ... | 2013 | 23748789 |
| conservation of dark recovery kinetic parameters and structural features in the pseudomonadaceae "short" light, oxygen, voltage (lov) protein family: implications for the design of lov-based optogenetic tools. | in bacteria and fungi, various light, oxygen, voltage (lov) sensory systems that lack a fused effector domain but instead contain only short n- and c-terminal extensions flanking the lov core exist. in the prokaryotic kingdom, this so-called "short" lov protein family represents the third largest lov photoreceptor family. this observation prompted us to study their distribution and phylogeny as well as their photochemical and structural properties in more detail. we recently described the slow a ... | 2013 | 23746326 |
| engineering of a hybrid biotransformation system for cytochrome p450sca-2 in escherichia coli. | p450sca-2 is an industrially important enzyme that stereoselectively converts mevastatin into pravastatin. however, little information or engineering efforts have been reported for this enzyme or its redox partner. in this study, we successfully reconstituted the p450sca-2 activity in escherichia coli by co-expression with putidaredoxin reductase (pdr) and putidaredoxin (pdx) from the pseudomonas putida cytochrome p450cam system. with an hplc-based screening assay, random mutagenesis was applied ... | 2013 | 23744742 |
| pseudomonas putida kt2442 as a platform for the biosynthesis of polyhydroxyalkanoates with adjustable monomer contents and compositions. | the β-oxidation weakened pseudomonas putida were established as a platform for the production of polyhydroxyalkanoates (pha) with adjustable monomer compositions and micro-structures. when mutant p. putida ktoyo6δc (phapcja.c) was cultivated on mixtures of sodium butyrate and sodium hexanoate (c4:c6), random copolymers of p(3hb-co-3hhx) consisting of 3-hydroxybutyrate (3hb), 3-hydroxyhexanoate (3hhx), were accumulated with 3hhx content ranged from 19 mol% to 75 mol%. while recombinant p. putida ... | 2013 | 23743426 |
| purification and identification of trichloroethylene induced proteins from stenotrophomonas maltophilia pm102 by immuno-affinity-chromatography and maldi-tof mass spectrometry. | a novel bacterial isolate capable of growth on trichloroethylene as the sole carbon source was identified as stenotrophomonas maltophilia pm102 by 16s rdna sequencing (genbank acc.no. jq797560). serum was obtained from a rabbit immunized with the total protein extracted from the pm102 isolate grown in 0.2% tce with 0.2% peptone. antibodies to the common antigens were removed by preadsorbing the serum antibody on total protein extracted from the pm102 strain grown in 0.2% peptone. western blot wi ... | 2013 | 23741645 |
| short rose-like rna thermometers control ibpa synthesis in pseudomonas species. | the bacterial small heat shock protein ibpa protects client proteins from aggregation. due to redundancy in the cellular chaperone network, deletion of the ibpa gene often leads to only a mild or no phenotypic defect. in this study, we show that a pseudomonas putida ibpa deletion mutant has a severe growth defect under heat stress conditions and reduced survival during recovery revealing a critical role of ibpa in heat tolerance. transcription of the ibpa gene depends on the alternative heat sho ... | 2013 | 23741480 |
| characterization of flavin-based fluorescent proteins: an emerging class of fluorescent reporters. | fluorescent reporter proteins based on flavin-binding photosensors were recently developed as a new class of genetically encoded probes characterized by small size and oxygen-independent maturation of fluorescence. flavin-based fluorescent proteins (fbfps) address two major limitations associated with existing fluorescent reporters derived from the green fluorescent protein (gfp)-namely, the overall large size and oxygen-dependent maturation of fluorescence of gfp. however, fbfps are at a nascen ... | 2013 | 23741385 |
| rescue of deleterious mutations by the compensatory y30f mutation in ketosteroid isomerase. | proteins have evolved to compensate for detrimental mutations. however, compensatory mechanisms for protein defects are not well understood. using ketosteroid isomerase (ksi), we investigated how second-site mutations could recover defective mutant function and stability. previous results revealed that the y30f mutation rescued the y14f, y55f and y14f/y55f mutants by increasing the catalytic activity by 23-, 3- and 1.3-fold, respectively, and the y55f mutant by increasing the stability by 3.3 kc ... | 2013 | 23740430 |
| elucidating the pseudomonas aeruginosa fatty acid degradation pathway: identification of additional fatty acyl-coa synthetase homologues. | the fatty acid (fa) degradation pathway of pseudomonas aeruginosa, an opportunistic pathogen, was recently shown to be involved in nutrient acquisition during balb/c mouse lung infection model. the source of fa in the lung is believed to be phosphatidylcholine, the major component of lung surfactant. previous research indicated that p. aeruginosa has more than two fatty acyl-coa synthetase genes (fadd; pa3299 and pa3300), which are responsible for activation of fas using atp and coenzyme a. thro ... | 2013 | 23737986 |
| particle-cell contact enhances antibacterial activity of silver nanoparticles. | it is generally accepted that antibacterial properties of ag nanoparticles (agnps) are dictated by their dissolved fraction. however, dissolution-based concept alone does not fully explain the toxic potency of nanoparticulate silver compared to silver ions. | 2013 | 23737965 |
| antibacterial activity of a lectin-like burkholderia cenocepacia protein. | bacteriocins of the llpa family have previously been characterized in the γ-proteobacteria pseudomonas and xanthomonas. these proteins are composed of two mmbl (monocot mannose-binding lectin) domains, a module predominantly and abundantly found in lectins from monocot plants. genes encoding four different types of llpa-like proteins were identified in genomes from strains belonging to the burkholderia cepacia complex (bcc) and the burkholderia pseudomallei group. a selected recombinant llpa-lik ... | 2013 | 23737242 |
| the catabolism of 2,4-xylenol and p-cresol share the enzymes for the oxidation of para-methyl group in pseudomonas putida ncimb 9866. | pseudomonas putida ncimb 9866 utilizes p-cresol or 2,4-xylenol as a sole carbon and energy source. enzymes catalyzing the oxidation of the para-methyl group of p-cresol have been studied in detail. however, those responsible for the oxidation of the para-methyl group in 2,4-xylenol catabolism are still not reported. in this study, real-time quantitative pcr analysis indicated pchc- and pchf-encoded p-cresol methylhydroxylase (pcmh) and pcha-encoded p-hydroxybenzaldehyde dehydrogenase (phbdd) in ... | 2014 | 23736872 |
| a membrane-integrated advanced scheme for treatment of industrial wastewater: dynamic modeling towards scale up. | modeling and simulation was carried out for an advanced membrane-integrated hybrid treatment process that ensures reuse of water with conversion and recovery of ammoniacal nitrogen as value-added struvite fertilizer from coke wastewater. while toxic cyanide was largely removed in a pre-chemical treatment unit using fenton's reagents under optimized conditions, more than 95% of nh4(+)-n could be recovered as a valuable by-product called struvite through addition of appropriate doses of magnesium ... | 2013 | 23735488 |
| rapid 16s rrna next-generation sequencing of polymicrobial clinical samples for diagnosis of complex bacterial infections. | classifying individual bacterial species comprising complex, polymicrobial patient specimens remains a challenge for culture-based and molecular microbiology techniques in common clinical use. we therefore adapted practices from metagenomics research to rapidly catalog the bacterial composition of clinical specimens directly from patients, without need for prior culture. we have combined a semiconductor deep sequencing protocol that produces reads spanning 16s ribosomal rna gene variable regions ... | 2013 | 23734239 |
| strategy for successful expression of the pseudomonas putida nitrile hydratase activator p14k in escherichia coli. | activators of nitrile hydratase (nhase) are essential for functional nhase biosynthesis. however, the activator p14k in p. putida is difficult to heterogeneously express, which retards the clarification of the mechanism of p14k involved in the maturation of nhase. although a strep tag containing p14k (strep-p14k) was over-expressed, its low expression level and low stability affect the further analysis. | 2013 | 23731949 |
| rise and dissemination of aminoglycoside resistance: the aac(6')-ib paradigm. | enzymatic modification is a prevalent mechanism by which bacteria defeat the action of antibiotics. aminoglycosides are often inactivated by aminoglycoside modifying enzymes encoded by genes present in the chromosome, plasmids, and other genetic elements. the aac(6')-ib (aminoglycoside 6'-n-acetyltransferase type ib) is an enzyme of clinical importance found in a wide variety of gram-negative pathogens. the aac(6')-ib enzyme is of interest not only because of his ubiquity but also because of oth ... | 2013 | 23730301 |
| transformation of pwwo in rhizobium leguminosarum dpt to engineer toluene degrading ability for rhizoremediation. | rhizoremediation of organic xenobiotics is based on interactions between plants and their associated micro-organisms. the present work was designed to engineer a bacterial system having toluene degradation ability along with plant growth promoting characteristics for effective rhizoremediation. pwwo harboring the genes responsible for toluene breakdown was isolated from pseudomonas putida mtcc 979 and successfully transformed in rhizobium dpt. this resulted in a bacterial strain (dpt(t)) which h ... | 2011 | 23729882 |
| transformation of pwwo in rhizobium leguminosarum dpt to engineer toluene degrading ability for rhizoremediation. | rhizoremediation of organic xenobiotics is based on interactions between plants and their associated micro-organisms. the present work was designed to engineer a bacterial system having toluene degradation ability along with plant growth promoting characteristics for effective rhizoremediation. pwwo harboring the genes responsible for toluene breakdown was isolated from pseudomonas putida mtcc 979 and successfully transformed in rhizobium dpt. this resulted in a bacterial strain (dpt(t)) which h ... | 2011 | 23729882 |
| nonproteinogenic amino acid building blocks for nonribosomal peptide and hybrid polyketide scaffolds. | freestanding nonproteinogenic amino acids have long been recognized for their antimetabolite properties and tendency to be uncovered to reactive functionalities by the catalytic action of target enzymes. by installing them regiospecifically into biogenic peptides and proteins, it may be possible to usher a new era at the interface between small molecule and large molecule medicinal chemistry. site-selective protein functionalization offers uniquely attractive strategies for posttranslational mod ... | 2013 | 23729217 |
| bacterial tethering analysis reveals a "run-reverse-turn" mechanism for pseudomonas species motility. | we have developed a program that can accurately analyze the dynamic properties of tethered bacterial cells. the program works especially well with cells that tend to give rise to unstable rotations, such as polar-flagellated bacteria. the program has two novel components. the first dynamically adjusts the center of the cell's rotational trajectories. the second applies piecewise linear approximation to the accumulated rotation curve to reduce noise and separate the motion of bacteria into phases ... | 2013 | 23728820 |
| actinobacillus pleuropneumoniae genes expression in biofilms cultured under static conditions and in a drip-flow apparatus. | actinobacillus pleuropneumoniae is the gram-negative bacterium responsible for porcine pleuropneumonia. this respiratory infection is highly contagious and characterized by high morbidity and mortality. the objectives of our study were to study the transcriptome of a. pleuropneumoniae biofilms at different stages and to develop a protocol to grow an a. pleuropneumoniae biofilm in a drip-flow apparatus. this biofilm reactor is a system with an air-liquid interface modeling lung-like environment. ... | 2013 | 23725589 |
| ecotoxicity of nanoparticles. | nanotechnology is a science of producing and utilizing nanosized particles that are measured in nanometers. the unique size-dependent properties make the nanoparticles superior and indispensable as they show unusual physical, chemical, and properties such as conductivity, heat transfer, melting temperature, optical properties, and magnetization. taking the advantages of these singular properties in order to develop new products is the main purpose of nanotechnology, and that is why it is regarde ... | 2013 | 23724300 |
| inhibitory effect of pseudomonas putida nitrogen-related phosphotransferase system on conjugative transfer of incp-9 plasmid from escherichia coli. | conjugative plasmid transfer systems have been well studied, but very little is known about the recipient factors that control horizontal transmission. a self-transmissible incp-9 naphthalene catabolic plasmid, nah7, carries the traf gene, whose product is considered to be a host-range modifier of nah7, because its traf deletion mutant (nah7df) is transmissible from pseudomonas putida to p. putida and escherichia coli and from e. coli to e. coli, but not from e. coli to p. putida. in this study, ... | 2013 | 23721112 |
| anthranilate degradation by a cold-adapted pseudomonas sp. | an alpine soil bacterium pseudomonas sp. strain pamc 25931 was characterized as eurypsychrophilic (both psychrophilic and mesotolerant) with a broad temperature range of 5-30 °c both for anthranilate (2-aminobenzoate) degradation and concomitant cell growth. two degradative gene clusters (antabc and catbca) were detected from a fosmid clone in the pamc 25931 genomic library; each cluster was confirmed to be specifically induced by anthranilate. when expressed in escherichia coli, the recombinant ... | 2015 | 23720227 |
| o-demethylations catalyzed by rieske nonheme iron monooxygenases involve the difficult oxidation of a saturated c-h bond. | dicamba monooxygenase (dmo) catalyzes the o-demethylation of dicamba (3,6-dichloro-2-methoxybenzoate) to produce 3,6-dichlorosalicylate and formaldehyde. recent crystallographic studies suggest that dmo catalyzes the challenging oxidation of a saturated c-h bond within the methyl group of dicamba to form a hemiacetal intermediate. testing of this hypothesis was made possible by our development of two new independent techniques. as a novel method to allow use of (18)o2 to follow reaction products ... | 2013 | 23719540 |
| microbial production of lactate-containing polyesters. | due to our increasing concerns on environmental problems and limited fossil resources, biobased production of chemicals and materials through biorefinery has been attracting much attention. optimization of the metabolic performance of microorganisms, the key biocatalysts for the efficient production of the desired target bioproducts, has been achieved by metabolic engineering. metabolic engineering allowed more efficient production of polyhydroxyalkanoates, a family of microbial polyesters. more ... | 2013 | 23718266 |
| synthesis, characterization, and in vivo efficacy of shell cross-linked nanoparticle formulations carrying silver antimicrobials as aerosolized therapeutics. | the use of nebulizable, nanoparticle-based antimicrobial delivery systems can improve efficacy and reduce toxicity for treatment of multi-drug-resistant bacteria in the chronically infected lungs of cystic fibrosis patients. nanoparticle vehicles are particularly useful for applying broad-spectrum silver-based antimicrobials, for instance, to improve the residence time of small-molecule silver carbene complexes (sccs) within the lung. therefore, we have synthesized multifunctional, shell cross-l ... | 2013 | 23718195 |
| tomato transcriptome and mutant analyses suggest a role for plant stress hormones in the interaction between fruit and botrytis cinerea. | fruit-pathogen interactions are a valuable biological system to study the role of plant development in the transition from resistance to susceptibility. in general, unripe fruit are resistant to pathogen infection but become increasingly more susceptible as they ripen. during ripening, fruit undergo significant physiological and biochemical changes that are coordinated by complex regulatory and hormonal signaling networks. the interplay between multiple plant stress hormones in the interaction b ... | 2013 | 23717322 |
| complete sequence of poz176, a 500-kilobase incp-2 plasmid encoding imp-9-mediated carbapenem resistance, from outbreak isolate pseudomonas aeruginosa 96. | pseudomonas aeruginosa 96 (pa96) was isolated during a multicenter surveillance study in guangzhou, china, in 2000. whole-genome sequencing of this outbreak strain facilitated analysis of its incp-2 carbapenem-resistant plasmid, poz176. the plasmid had a length of 500,839 bp and an average percent g+c content of 57%. of the 618 predicted open reading frames, 65% encode hypothetical proteins. the poz176 backbone is not closely related to any plasmids thus far sequenced, but some similarity to pqb ... | 2013 | 23716048 |
| engineering microbial cells for the biosynthesis of natural compounds of pharmaceutical significance. | microbes constitute important platforms for the biosynthesis of numerous molecules of pharmaceutical interest such as antitumor, anticancer, antiviral, antihypertensive, antiparasitic, antioxidant, immunological agents, and antibiotics as well as hormones, belonging to various chemical families, for instance, terpenoids, alkaloids, polyphenols, polyketides, amines, and proteins. engineering microbial factories offers rich opportunities for the production of natural products that are too complex ... | 2013 | 23710459 |
| detection, distribution and characterization of novel superoxide dismutases from yersinia enterocolitica biovar 1a. | superoxide dismutases (sods) cause dismutation of superoxide radicals to hydrogen peroxide and oxygen. besides protecting the cells against oxidative damage by endogenously generated oxygen radicals, sods play an important role in intraphagocytic survival of pathogenic bacteria. the complete genome sequences of yersinia enterocolitica strains show presence of three different sod genes. however, not much is known about the types of sods present in y. enterocolitica, their characteristics and role ... | 2013 | 23704955 |
| acyltransferases in bacteria. | long-chain-length hydrophobic acyl residues play a vital role in a multitude of essential biological structures and processes. they build the inner hydrophobic layers of biological membranes, are converted to intracellular storage compounds, and are used to modify protein properties or function as membrane anchors, to name only a few functions. acyl thioesters are transferred by acyltransferases or transacylases to a variety of different substrates or are polymerized to lipophilic storage compou ... | 2013 | 23699259 |
| sad phasing towards structure determination of a thermostable rieske ferredoxin with a novel stabilizing disulfide bridge. | rieske proteins and rieske ferredoxins are ubiquitous electron-transfer metalloproteins that are characterized by a [2fe-2s] cluster coordinated by pairs of cysteine and histidine residues. the thermoacidophilic archaeon acidianus ambivalens contains a rieske ferredoxin termed rfd2, which has an hitherto unknown additional region of 40-44 residues at the c-terminus with a cx3c motif that introduces a novel disulfide bond within the rieske fold. rfd2 was crystallized with the aim of determining i ... | 2013 | 23695576 |
| transcriptional activation of the crcz and crcy regulatory rnas by the cbrb response regulator in pseudomonas putida. | the cbrab two-component system has been described as a high-ranked element in the regulatory hierarchy of pseudomonas putida that controls a variety of metabolic and behavioural traits required for adaptation to changing environmental conditions. we show that the response regulatory protein cbrb, an activator of σ(n) -dependent promoters, directly controls the expression of the small rnas crcz and crcy in p. putida. these two rnas sequester the protein crc, which is a translational repressor of ... | 2013 | 23692431 |
| the antimicrobial compound xantholysin defines a new group of pseudomonas cyclic lipopeptides. | the rhizosphere isolate pseudomonas putida bw11m1 produces a mixture of cyclic lipopeptide congeners, designated xantholysins. properties of the major compound xantholysin a, shared with several other pseudomonas lipopeptides, include antifungal activity and toxicity to gram-positive bacteria, a supportive role in biofilm formation, and facilitation of surface colonization through swarming. atypical is the lipopeptide's capacity to inhibit some gram-negative bacteria, including several xanthomon ... | 2013 | 23690965 |
| clearance of pseudomonas aeruginosa foreign-body biofilm infections through reduction of the cyclic di-gmp level in the bacteria. | opportunistic pathogenic bacteria can engage in biofilm-based infections that evade immune responses and develop into chronic conditions. because conventional antimicrobials cannot efficiently eradicate biofilms, there is an urgent need to develop alternative measures to combat biofilm infections. it has recently been established that the secondary messenger cyclic diguanosine monophosphate (c-di-gmp) functions as a positive regulator of biofilm formation in several different bacteria. in the pr ... | 2013 | 23690403 |
| accumulation of inorganic polyphosphate enables stress endurance and catalytic vigour in pseudomonas putida kt2440. | accumulation of inorganic polyphosphate (polyp), a persistent trait throughout the whole tree of life, is claimed to play a fundamental role in enduring environmental insults in a large variety of microorganisms. the share of polyp in the tolerance of the soil bacterium pseudomonas putida kt2440 to a suite of physicochemical stresses has been studied on the background of its capacity as a host of oxidative biotransformations. | 2013 | 23687963 |
| broad host range vectors for expression of proteins with (twin-) strep-tag, his-tag and engineered, export optimized yellow fluorescent protein. | in current protein research, a limitation still is the production of active recombinant proteins or native protein associations to assess their function. especially the localization and analysis of protein-complexes or the identification of modifications and small molecule interaction partners by co-purification experiments requires a controllable expression of affinity- and/or fluorescence tagged variants of a protein of interest in its native cellular background. advantages of periplasmic and/ ... | 2013 | 23687945 |
| how to achieve high-level expression of microbial enzymes: strategies and perspectives. | microbial enzymes have been used in a large number of fields, such as chemical, agricultural and biopharmaceutical industries. the enzyme production rate and yield are the main factors to consider when choosing the appropriate expression system for the production of recombinant proteins. recombinant enzymes have been expressed in bacteria (e.g., escherichia coli, bacillus and lactic acid bacteria), filamentous fungi (e.g., aspergillus) and yeasts (e.g., pichia pastoris). the favorable and very a ... | 2013 | 23686280 |
| a new large-dna-fragment delivery system based on integrase activity from an integrative and conjugative element. | during the past few decades, numerous plasmid vectors have been developed for cloning, gene expression analysis, and genetic engineering. cloning procedures typically rely on pcr amplification, dna fragment restriction digestion, recovery, and ligation, but increasingly, procedures are being developed to assemble large synthetic dnas. in this study, we developed a new gene delivery system using the integrase activity of an integrative and conjugative element (ice). the advantage of the integrase ... | 2013 | 23686268 |
| increased lysine content is the main characteristic of the soluble form of the polyamide cyanophycin synthesized by recombinant escherichia coli. | cyanophycin, a polyamide of cyanobacterial or noncyanobacterial origin consisting of aspartate, arginine, and lysine, was synthesized in different recombinant strains of escherichia coli expressing cpha from synechocystis sp. strain pcc 6308 or pcc 6803, anabaena sp. strain pcc 7120, or acinetobacter calcoaceticus adp1. the molar aspartate/arginine/lysine ratio of the water-soluble form isolated from a recombinant strain expressing cpha6308 was 1:0.5:0.5, with a lysine content higher than any ev ... | 2013 | 23686266 |
| tyrb-2 and phhc genes of pseudomonas putida encode aromatic amino acid aminotransferase isozymes: evidence at the protein level. | two pseudomonas putida aminotransferases (arat i and arat ii) that exhibit activity toward l-tryptophan were purified 104- and 395-fold using a six-stage purification procedure involving ammonium sulfate fractionation and chromatographic separation on phenyl-sepharose, sephadex g-100 superfine, deae-cellulose and protein-pack q8 hr columns. mass spectrometry analysis resulted in the identification of 27 and 20 % of the total arat i and arat ii amino acid sequences. in addition, n-terminal sequen ... | 2013 | 23685963 |
| synthetic mammalian trigger-controlled bipartite transcription factors. | synthetic biology has significantly advanced the design of synthetic control devices, gene circuits and networks that can reprogram mammalian cells in a trigger-inducible manner. prokaryotic helix-turn-helix motifs have become the standard resource to design synthetic mammalian transcription factors that tune chimeric promoters in a small molecule-responsive manner. we have identified a family of actinomycetes transcriptional repressor proteins showing a tandem tetr-family signature and have use ... | 2013 | 23685433 |
| [2fe-2s]-ferredoxin binds directly to cysteine desulfurase and supplies an electron for iron-sulfur cluster assembly but is displaced by the scaffold protein or bacterial frataxin. | escherichia coli [2fe-2s]-ferredoxin (fdx) is encoded by the isc operon along with other proteins involved in the 'house-keeping' mechanism of iron-sulfur cluster biogenesis. although it has been proposed that fdx supplies electrons to reduce sulfane sulfur (s(0)) produced by the cysteine desulfurase (iscs) to sulfide (s(2-)) as required for the assembly of fe-s clusters on the scaffold protein (iscu), direct experimental evidence for the role of fdx has been lacking. here, we show that fdx (in ... | 2013 | 23682711 |
| urea output by l3 teladorsagia circumcincta and some properties of two urea producing enzymes. | like several other parasites, teladorsagia circumcincta secretes or excretes urea, but neither the rate of efflux nor the possible metabolic sources of the urea has been considered. | 2013 | 23682271 |
| peptidoglycan at its peaks: how chromatographic analyses can reveal bacterial cell wall structure and assembly. | the peptidoglycan (pg) cell wall is a unique macromolecule responsible for both shape determination and cellular integrity under osmotic stress in virtually all bacteria. a quantitative understanding of the relationships between pg architecture, morphogenesis, immune system activation and pathogenesis can provide molecular-scale insights into the function of proteins involved in cell wall synthesis and cell growth. high-performance liquid chromatography (hplc) has played an important role in our ... | 2013 | 23679048 |
| high specificity in cher methyltransferase function: cher2 of pseudomonas putida is essential for chemotaxis, whereas cher1 is involved in biofilm formation. | chemosensory pathways are a major signal transduction mechanism in bacteria. cher methyltransferases catalyze the methylation of the cytosolic signaling domain of chemoreceptors and are among the core proteins of chemosensory cascades. these enzymes have primarily been studied escherichia coli and salmonella typhimurium, which possess a single cher involved in chemotaxis. many other bacteria possess multiple cher genes. because the sequences of chemoreceptor signaling domains are highly conserve ... | 2013 | 23677992 |
| bioavailability of heavy metals in soil: impact on microbial biodegradation of organic compounds and possible improvement strategies. | co-contamination of the environment with toxic chlorinated organic and heavy metal pollutants is one of the major problems facing industrialized nations today. heavy metals may inhibit biodegradation of chlorinated organics by interacting with enzymes directly involved in biodegradation or those involved in general metabolism. predictions of metal toxicity effects on organic pollutant biodegradation in co-contaminated soil and water environments is difficult since heavy metals may be present in ... | 2013 | 23676353 |
| engineering pseudomonas protegens pf-5 for nitrogen fixation and its application to improve plant growth under nitrogen-deficient conditions. | nitrogen is the second most critical factor for crop production after water. in this study, the beneficial rhizobacterium pseudomonas protegens pf-5 was genetically modified to fix nitrogen using the genes encoding the nitrogenase of pseudomonas stutzeri a1501 via the x940 cosmid. pf-5 x940 was able to grow in l medium without nitrogen, displayed high nitrogenase activity and released significant quantities of ammonium to the medium. pf-5 x940 also showed constitutive expression and enzymatic ac ... | 2013 | 23675499 |
| reduce manual curation by combining gene predictions from multiple annotation engines, a case study of start codon prediction. | nowadays, prokaryotic genomes are sequenced faster than the capacity to manually curate gene annotations. automated genome annotation engines provide users a straight-forward and complete solution for predicting orf coordinates and function. for many labs, the use of ages is therefore essential to decrease the time necessary for annotating a given prokaryotic genome. however, it is not uncommon for ages to provide different and sometimes conflicting predictions. combining multiple ages might all ... | 2013 | 23675487 |
| clinical features and laboratory diagnosis of infection with the potential bioterrorism agents burkholderia mallei and burkholderia pseudomallei. | burkholderia mallei and burkholderia pseudomallei are the causative organisms of glanders and melioidosis, respectively. although now rare in western countries, both organisms have recently gained much interest because of their unique potential as bioterrorism agents. these organisms are less familiar to medical and laboratory personnel than other select bioterrorism bacterial agents and thus heightened awareness of glanders and melioidosis is crucial in order to enable adequate emergency prepar ... | 2007 | 23675037 |
| the solution structures of two prophage homologues of the bacteriophage λ ea8.5 protein reveal a newly discovered hybrid homeodomain/zinc-finger fold. | a cluster of genes in the exoxis region of bacteriophage λ are capable of inhibiting the initiation of dna synthesis in escherichia coli. the most indispensible gene in this region is ea8.5. here, we report the nuclear magnetic resonance structures of two ea8.5 orthologs from enteropathogenic e. coli and pseudomonas putida prophages. both proteins are characterized by a fused homeodomain/zinc-finger fold that escaped detection by primary sequence search methods. while these folds are both associ ... | 2013 | 23672713 |
| characterization of olfactory sensilla of the olive fly: behavioral and electrophysiological responses to volatile organic compounds from the host plant and bacterial filtrate. | the responses of olive fly (bactrocera oleae) antennal and palpal olfactory receptors to odors emitted by pseudomonas putida bacterial filtrate and to volatiles from a host plant were evaluated using electrophysiological and behavioral bioassays. morphological identification of olfactory receptors was also performed. the third antennal segment (flagellum) bears four types of multiporous sensilla: trichoid, short basiconica, clavate and grooved. maxillary palps have mechanosensory bristles and mu ... | 2013 | 23669464 |
| molecular characterization of camphor utilizing bacterial isolates from refinery sludge and detection of target loci-cytochrome p-450 cam mono oxygenase (cam c gene) by pcr and gene probe. | this study presents the isolation and molecular characterization of bacterial strains utilizing 1, 7, 7-trimethylbicyclo (2.2.1) heptane-2-one (camphor) as a sole source of carbon, isolated from the biomass sludge sample collected from an effluent treatment plant of mathura refinery limited (mrl), india. initial screening was carried out where the 16s rdna pcr was performed using reported eubacterial primer set followed by amplified ribosomal dna restriction analysis (ardra). about 47% of the is ... | 2013 | 23667817 |
| identification of antimony- and arsenic-oxidizing bacteria associated with antimony mine tailing. | antimony (sb) is a naturally occurring toxic element commonly associated with arsenic (as) in the environment and both elements have similar chemistry and toxicity. increasing numbers of studies have focused on microbial as transformations, while microbial sb interactions are still not well understood. to gain insight into microbial roles in the geochemical cycling of sb and as, soils from sb mine tailing were examined for the presence of sb- and as-oxidizing bacteria. after aerobic enrichment c ... | 2013 | 23666539 |
| microbial production of isoquinoline alkaloids as plant secondary metabolites based on metabolic engineering research. | plants produce a variety of secondary metabolites that possess strong physiological activities. unfortunately, however, their production can suffer from a variety of serious problems, including low levels of productivity and heterogeneous quality, as well as difficulty in raw material supply. in contrast, microorganisms can be used to produce their primary and some of their secondary metabolites in a controlled environment, thus assuring high levels of efficiency and uniform quality. in an attem ... | 2013 | 23666088 |
| 2-ketogluconic acid secretion by incorporation of pseudomonas putida kt 2440 gluconate dehydrogenase (gad) operon in enterobacter asburiae psi3 improves mineral phosphate solubilization. | enterobacter asburiae psi3 is known to efficiently solubilize rock phosphate by secretion of approximately 50 mm gluconic acid in tris-buffered medium in the presence of 75 mm glucose and in a mixture of seven aldosugars each at 15 mm concentration, mimicking alkaline vertisol soils. efficacy of this bacterium in the rhizosphere requires p release in the presence of low amount of sugars. to achieve this, e. asburiae psi3 has been manipulated to express gluconate dehydrogenase (gad) operon of pse ... | 2013 | 23666029 |
| inactivation of pseudomonas putida by pulsed electric field treatment: a study on the correlation of treatment parameters and inactivation efficiency in the short-pulse range. | an important issue for an economic application of the pulsed electric field treatment for bacterial decontamination of wastewater is the specific treatment energy needed for effective reduction of bacterial populations. the present experimental study performed in a field amplitude range of 40 > e > 200 kv/cm and for a suspension conductivity of 0.01 = κ(e) > 0.2 s/m focusses on the application of short pulses, 25 ns > t > 10 μs, of rectangular, bipolar and exponential shape and was made on pseud ... | 2013 | 23660812 |
| vaccination efficiency of surface antigens and killed whole cell of pseudomonas putida in large yellow croaker (pseudosciaena crocea). | large yellow croaker (pseudosciaena crocea), a major marine fish aquacultured in the southeastern coastal region of china, has become endangered by the pathogen pseudomonas putida in recent years. p. putida infections occur in low water temperatures when fish reduce food intake, thus oral antibiotic administration is not practical. therefore, vaccination may be the only method to prevent the infection. in the present study, main surface antigens of p. putida, including lipopolysaccharide (lps), ... | 2013 | 23659996 |
| the impact of the conjugative incp-1 plasmid pkjk5 on multispecies biofilm formation is dependent on the plasmid host. | horizontal gene transfer by conjugation has been reported to increase overall biofilm formation. biofilm is considered a hot spot for plasmid transfer, and it has been found that social interactions during biofilm formation can increase the biomass. in this study, we demonstrate a contrast to previous studies by showing that the conjugative incp-1 plasmid pkjk5 influences biofilm formation negatively. the results showed that a co-culture (pseudomonas putida, kluyvera sp., and escherichia coli) f ... | 2013 | 23659318 |
| the three-species consortium of genetically improved strains cupriavidus necator rw112, burkholderia xenovorans rw118, and pseudomonas pseudoalcaligenes rw120 grows with technical polychlorobiphenyl, aroclor 1242. | burkholderia xenovorans lb400, cupriavidus necator h850, and pseudomonas pseudoalcaligenes kf707 are bacterial strains able to mineralize biphenyl and to co-oxidize many of its halogenated derivatives (pcbs). only strain lb400 also mineralizes a few mono- and dichlorobiphenyls, due to the presence of a functioning chlorocatechol pathway. here, we used a tn5-based minitransposon shuttle system to chromosomically introduce genes tcbrcdef, encoding the chlorocatechol pathway into kf707, and genes c ... | 2013 | 23658554 |
| first detection in europe of the metallo-β-lactamase imp-15 in clinical strains of pseudomonas putida and pseudomonas aeruginosa. | in a prospective study (2009-2011) in healthcare institutions from the canary islands (spain), 6 out of 298 carbapenem non-susceptible pseudomonas aeruginosa isolates produced a metallo-β-lactamase: four imp-15, two vim-2 (including one imp-15-positive isolate) and one vim-1. multilocus sequence typing identified the single vim-1-producing isolate as clone st111 and two imp-15-producing isolates as st606, but, strikingly, bacterial re-identification revealed that the other three isolates (produc ... | 2013 | 23656535 |
| transcription factor-based screens and synthetic selections for microbial small-molecule biosynthesis. | continued advances in metabolic engineering are increasing the number of small molecules being targeted for microbial production. pathway yields and productivities, however, are often suboptimal, and strain improvement remains a persistent challenge given that the majority of small molecules are difficult to screen for and their biosynthesis does not improve host fitness. in this work, we have developed a generalized approach to screen or select for improved small-molecule biosynthesis using tra ... | 2012 | 23656325 |
| bacterial invasion potential in water is determined by nutrient availability and the indigenous community. | in drinking water (dw) and the distribution systems, bacterial growth and biofilm formation have to be controlled both for limiting taste or odour development and preventing clogging or biocorrosion problems. after a contamination with undesired bacteria, factors like nutrient availability and temperature will influence the survival of these invaders. understanding the conditions enabling invaders to proliferate is essential for a holistic approach towards microbial risk assessment in dw. pseudo ... | 2013 | 23656310 |
| decaffeination and measurement of caffeine content by addicted escherichia coli with a refactored n-demethylation operon from pseudomonas putida cbb5. | the widespread use of caffeine (1,3,7-trimethylxanthine) and other methylxanthines in beverages and pharmaceuticals has led to significant environmental pollution. we have developed a portable caffeine degradation operon by refactoring the alkylxanthine degradation (alx) gene cluster from pseudomonas putida cbb5 to function in escherichia coli. in the process, we discovered that adding a glutathione s-transferase from janthinobacterium sp. marseille was necessary to achieve n 7 -demethylation ac ... | 2013 | 23654268 |
| short and long-term genome stability analysis of prokaryotic genomes. | gene organization dynamics is actively studied because it provides useful evolutionary information, makes functional annotation easier and often enables to characterize pathogens. there is therefore a strong interest in understanding the variability of this trait and the possible correlations with life-style. two kinds of events affect genome organization: on one hand translocations and recombinations change the relative position of genes shared by two genomes (i.e. the backbone gene order); on ... | 2013 | 23651581 |
| p-hydroxycinnamic acid production directly from cellulose using endoglucanase- and tyrosine ammonia lyase-expressing streptomyces lividans. | p-hydroxycinnamic acid (phca) is an aromatic compound that serves as a starting material for the production of many commercially valuable chemicals, such as fragrances and pharmaceuticals, and is also used in the synthesis of thermostable polymers. however, chemical synthesis of phca is both costly and harmful to the environment. although phca production using microbes has been widely studied, there remains a need for more cost-effective methods, such as the use of biomass as a carbon source. in ... | 2013 | 23651460 |
| predatory bacteria: a potential ally against multidrug-resistant gram-negative pathogens. | multidrug-resistant (mdr) gram-negative bacteria have emerged as a serious threat to human and animal health. bdellovibrio spp. and micavibrio spp. are gram-negative bacteria that prey on other gram-negative bacteria. in this study, the ability of bdellovibrio bacteriovorus and micavibrio aeruginosavorus to prey on mdr gram-negative clinical strains was examined. although the potential use of predatory bacteria to attack mdr pathogens has been suggested, the data supporting these claims is lacki ... | 2013 | 23650563 |
| microbial biosensors: engineered microorganisms as the sensing machinery. | whole-cell biosensors are a good alternative to enzyme-based biosensors since they offer the benefits of low cost and improved stability. in recent years, live cells have been employed as biosensors for a wide range of targets. in this review, we will focus on the use of microorganisms that are genetically modified with the desirable outputs in order to improve the biosensor performance. different methodologies based on genetic/protein engineering and synthetic biology to construct microorganism ... | 2013 | 23648649 |
| a novel pair of inducible expression vectors for use in methylobacterium extorquens. | due to the ever increasing use of diverse microbial taxa in basic research and industrial settings, there is a growing need for genetic tools to alter the physiology of these organisms. in particular, there is a dearth of inducible expression systems available for bacteria outside commonly used γ-proteobacteria, such as escherichia coli or pseudomonas species. to this end, we have sought to develop a pair of inducible expression vectors for use in the α-proteobacterium methylobacterium extorquen ... | 2013 | 23648175 |
| serum dihydrolipoamide dehydrogenase is a labile enzyme. | dihydrolipoamide dehydrogenase (dldh) is a multifunctional oxidoreductase and is well known as an essential component of four mammalian mitochondrial multienzyme complexes: pyruvate dehydrogenase, α-ketoglutarate dehydrogenase, branched chain α-keto acid dehydrogenase, and the glycine cleavage system. however, existence of extracellular dldh in mammals, if any, has not been clearly defined. the present article reports identification and biochemical characterization of serum dldh. proteomic analy ... | 2013 | 23646291 |
| adaptation of the hydrocarbonoclastic bacterium alcanivorax borkumensis sk2 to alkanes and toxic organic compounds: a physiological and transcriptomic approach. | the marine hydrocarbonoclastic bacterium alcanivorax borkumensis is able to degrade mixtures of n-alkanes as they occur in marine oil spills. however, investigations of growth behavior and physiology of these bacteria when cultivated with n-alkanes of different chain lengths (c6 to c30) as the substrates are still lacking. growth rates increased with increasing alkane chain length up to a maximum between c12 and c19, with no evident difference between even- and odd-numbered chain lengths, before ... | 2013 | 23645199 |