the regulated outer membrane protein omp21 from comamonas acidovorans is identified as a member of a new family of eight-stranded beta-sheet proteins by its sequence and properties.omp21, a minor outer membrane protein of the soil bacterium comamonas acidovorans, was purified from a spontaneous mutant lacking a surface layer and long-chain lipopolysaccharide. omp21 synthesis is enhanced by oxygen depletion, and the protein has a variable electrophoretic mobility in sodium dodecyl sulfate-polyacrylamide gel electrophoresis due to its heat-modifiable behavior. the structural gene omp21 encodes a precursor of 204 amino acids with a putative signal peptide of 21 amino acids. m ...19989683466
phylogenetic relationships among members of the comamonadaceae, and description of delftia acidovorans (den dooren de jong 1926 and tamaoka et al. 1987) gen. nov., comb. nov.the phylogenetic relationships among members of the family comamonadaceae and several unclassified strains were studied by direct sequencing of their pcr-amplified 16s rrna genes. based on the 16s rrna gene sequence analysis, members of the family formed a coherent group. the closest relatives are species of the rubrivivax sub-group: leptothrix discophora, ideonella dechloratans and rubrivivax gelatinosus. the genus hydrogenophaga formed two subclusters, as did the species of acidovorax, whereas ...199910319477
novel screening methods--the key to cloning commercially successful biocatalysts.providing sufficient biocatalyst to support the demands of multi tonne product supply can be problematical. here we describe how screening for and cloning a gamma-lactamase overcame biocatalyst supply issues, and greatly improved the actual biocatalytic process. the isolation of an expressing gamma-lactamase clone from a gene library necessitated a combination of classical molecular biology techniques together with innovative screening methods to identify a functional clone. once isolated the en ...199910579521
an extractive membrane biofilm reactor for degradation of 1,3-dichloropropene in industrial waste water.a bacterial biofilm, capable of mineralising a technical mixture of cis- and trans-1,3-dichloropropene (dcpe), was enriched on the biomedium side of an extractive membrane biofilm reactor (embr). the membrane separates the biomedium from the industrial waste water, in terms of ph, ionic strength and the concentration of toxic chemicals. the biofilm, attached to a silicone membrane, is able to mineralize dcpe after its diffusion through the membrane. five bacterial strains with degradation capabi ...199910616720
comamonas acidovorans strain mc1: a new isolate capable of degrading the chiral herbicides dichlorprop and mecoprop and the herbicides 2,4-d and mcpa.a gram-negative prototrophic bacterial species, strain mc1, was isolated from the vicinity of herbicide-contaminated building rubble and identified by 16s rdna sequence analysis, its physiological properties, gc content, and fatty acid composition as comamonas acidovorans. this strain displays activity for the productive degradation of the two enantiomers of dichlorprop [(rs)-2-(2,4-dichlorophenoxy-)propionate; (rs)-2,4-dp] and mecoprop [(rs)-2-(4-chloro-2-methyl-) phenoxypropionate; (rs)-mcpp] ...199910652787
factors affecting the freeze-fracture morphology of in vivo polyhydroxyalkanoate granules.interesting morphologies were observed when comamonas acidovorans containing polyhydroxyalkanoates (pha) of various compositions was freeze-fractured at temperatures far below the glass transition temperatures of pha. in vivo granules of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) comparatively showed the most ductility, and could be stretched extensively. contrary to the uniform needle-type deformation shown by the poly(3-hydroxybutyrate) homopolymer when fractured at -110 degrees c, copolymer ...200010779866
enantiomeric degradation of 2-(4-sulfophenyl)butyrate via 4-sulfocatechol in delftia acidovorans spb1.enrichment cultures with enantiomeric 2-(4-sulfophenyl)butyrate (spb) as the sole added source(s) of carbon and energy for growth yielded a pure culture of a degradative bacterium, which was identified as delftia acidovorans spb1. the organism utilized the enantiomers sequentially. r-spb was utilized first (specific growth rate [mu] = 0.28 h(-1)), with transient excretion of an unknown intermediate, which was identified as 4-sulfocatechol (4sc). utilization of s-spb was slower (mu = 0.016 h(-1)) ...200010788358
crystal structure of omp32, the anion-selective porin from comamonas acidovorans, in complex with a periplasmic peptide at 2.1 a resolution.porins provide diffusion channels for salts and small organic molecules in the outer membrane of bacteria. in ompf from escherichia coli and related porins, an electrostatic field across the channel and a potential, originating from a surplus of negative charges, create moderate cation selectivity. here, we investigate the strongly anion-selective porin omp32 from comamonas acidovorans, which is closely homologous to the porins of pathogenic bordetella and neisseria species.200010986465
characterization of strain hy99, a novel microorganism capable of aerobic and anaerobic degradation of aniline.we have characterized a novel microorganism, strain hy99, which is capable of aerobic and anaerobic degradation of aniline. strain hy99 was found to aerobically metabolize aniline via catechol and 2-hydroxymuconic semialdehyde intermediates, and to transform aniline via p-aminobenzoate in anaerobic environments. physiological and biochemical tests revealed that strain hy99 was most similar to delftia acidovorans, but unlike d. acidovorans, strain hy99 was able to metabolize aniline under anaerob ...200011034282
expression, two-dimensional crystallization, and three-dimensional reconstruction of the beta8 outer membrane protein omp21 from comamonas acidovorans.the omp21 protein from the proteobacterium comamonas (delftia) acidovorans belongs to the recently described beta8 family of outer membrane proteins, characterized by eight antiparallel beta-strands which form a beta-barrel. this family includes virulence proteins, ompa and ompx from escherichia coli, and other related molecules. after we established an expression system, recombinant omp21 was purified by ni(2+) chelation affinity chromatography and refolded in situ while bound to resin. the nat ...200011042080
comamonas acidovorans keratitis in a hydrogel contact lens present an unusual case of keratitis in a patient who wears hydrogel contact lenses that are replaced on a monthly basis. the agent isolated was comamonas acidovorans, a species of pseudomonas.200111215608
genetic diversity among 3-chloroaniline- and aniline-degrading strains of the comamonadaceae.we examined the diversity of the plasmids and of the gene tdnq, involved in the oxidative deamination of aniline, in five bacterial strains that are able to metabolize both aniline and 3-chloroaniline (3-ca). three strains have been described and identified previously, i.e., comamonas testosteroni i2 and delftia acidovorans ca28 and bn3.1. strains lme1 and b8c were isolated in this study from linuron-treated soil and from a wastewater treatment plant, respectively, and were both identified as d. ...200111229899
physiological and genetic characteristics of two bacterial strains utilizing phenoxypropionate and phenoxyacetate herbicides.two strains, rhodoferax sp. p230 and delftia (comamonas) acidovorans mci, have previously been shown to carry activities for the degradation of the two enantiomers of (rs)-2-(2,4-dichlorophenoxy-)propionate (dichlorprop) and (rs)-2-(4-chloro-2-methylphenoxy-)propionate (mecoprop) and, in addition, are capable of degrading phenoxyacetate derivatives 2.4-dichlorophenoxyacetate (2,4-d) and 4-chloro-2-methylphenoxyacetate (mcpa). metabolism of the herbicides is initiated by alpha-ketoglutarate-depen ...200111572451
the coenzyme a-dependent, non-beta-oxidation pathway and not direct deacetylation is the major route for ferulic acid degradation in delftia acidovorans.the gene loci fcs and ech, encoding feruloyl-coa synthetase and enoyl-coa hydratase/aldolase, respectively, are involved in the ferulic acid catabolism in delftia acidovorans. the amino acid sequence deduced from ech exhibited 51% identity to the enoyl-coa hydratase/aldolase from pseudomonas sp. strain hr199, indicating that the enzyme from d. acidovorans represents a new lineage of this protein. the genes fcs and ech were expressed in escherichia coli enabling the recombinant strain to transfor ...200111728709
selective enrichment and characterization of a phosphorus-removing bacterial consortium from activated sludge.under alternating aerobic/anaerobic conditions and without additional carbon sources, a bacterial consortium consisting initially of 18 bacterial strains was obtained in a sequence batch reactor. the phosphorus removal capability could only be maintained using sterile filtrate of activated sludge as medium. the addition of calcium and magnesium salts, as well as vitamins and trace elements, to autoclaved sterile filtrate of activated sludge was not sufficient to achieve stable phosphorus removal ...200211831470
comamonas koreensis sp. nov., a non-motile species from wetland in woopo, korea.a bacterial strain, designated yh12t, was isolated from a wetland sample collected from woopo, republic of korea, and characterized using a polyphasic approach. analysis of 16s rdna indicated that the isolate formed a monophyletic clade with the members of the genus comamonas. the closest phylogenetic relative among the valid species was comamonas testosteroni, with 96.6% 16s rdna similarity. the chemotaxonomic properties of the wetland isolate supported its membership of the genus comamonas, as ...200211931145
degradation of aniline by newly isolated, extremely aniline-tolerant delftia sp. an3.a bacterial strain, an3, which was able to use aniline or acetanilide as sole carbon, nitrogen and energy sources was isolated from activated sludge and identified as delftiasp. an3. this strain was capable of growing on concentrations of aniline up to 53.8 mm (5000 mg/l). substituted anilines such as n-methylaniline, n, n-dimethylaniline, 2-methylaniline, 4-methylaniline, 2-chloroaniline, 3-chloroaniline, o-aminoaniline, m-aminoaniline, p-aminoaniline, and sulfanilic acid did not support the gr ...200211956754
characterization of a class ii defective transposon carrying two haloacetate dehalogenase genes from delftia acidovorans plasmid puo1.the two haloacetate dehalogenase genes, dehh1 and dehh2, on the 65-kb plasmid puo1 from delftia acidovorans strain b were found to be located on transposable elements. the dehh2 gene was carried on an 8.9-kb class i composite transposon (tnhad1) that was flanked by two directly repeated copies of is1071, is1071l and is1071r. the dehh1 gene was also flanked by is1071l and a truncated version of is1071 (is1071n). tnhad1, dehh1, and is1071n were located on a 15.6-kb class ii transposon (tnhad2) who ...200211976102
electrostatic properties of the anion selective porin omp32 from delftia acidovorans and of the arginine cluster of bacterial porins.the functional properties of the anion-selective porin omp32 from the bacterium delftia acidovorans, formerly comamonas acidovorans, are determined by the particularly narrow channel constriction and the electrostatic field inside and outside the pore. a cluster of arginines (arg 38, arg 75, and arg 133) determines the electrostatic field close to the constriction zone. stacked amino acids carrying charges are prone to drastic pk(a) shifts. however, optimized calculations of the titration behavi ...200212021430
bioconversion of 3 beta-acetoxypregna-5,16-diene-20-one to androsta-1,4-diene-3,17-dione by mixed bacterial isolate a bacterium capable of degrading 3 beta-acetoxypregna-5,16-diene-20-one (16-dpa) to androsta-1,4-diene-3,17-dione (add) and to decipher the biodegradation pathway.200212100580
infectious keratitis manifesting as a white plaque on the cornea. 200212149067
assimilatory detoxification of herbicides by delftia acidovorans mc1: induction of two chlorocatechol 1,2-dioxygenases as a response to chemostress.proteome analysis of bacteria that can detoxify harmful organic compounds enables the discovery of enzymes involved in the biodegradation of these substances and proteins that protect the cell against poisoning. exposure of delftia acidovorans mc1 to 2,4-dichlorophenoxypropionic acid and its metabolites 2,4-dichlorophenol and 3,5-dichlorocatechol during growth on pyruvate as a source of carbon and energy induced several proteins. contrary to the general hypothesis that lipophilic or reactive com ...200212213933
the two enantiospecific dichlorprop/alpha-ketoglutarate-dioxygenases from delftia acidovorans mc1--protein and sequence data of rdpa and sdpa.two alpha-ketoglutarate-dependent dioxygenases carrying enantiospecific activity for the etherolytic cleavage of racemic phenoxypropionate herbicides [(rs)-2-(2,4-dichlorophenoxy)propionate and (rs)-2-(4-chloro-2-methylphenoxy)propionate] from delftia acidovorans mc1 were characterized with respect to protein and sequence data. the (s)-phenoxypropionate/alpha-ketoglutarate-dioxygenase (sdpa) appeared as a monomeric enzyme with a molecular weight of 32 kda in the presence of sds. n-terminal seque ...200212501996
gene cloning, purification, and characterization of a phosphodiesterase from delftia acidovorans.a novel phosphodiesterase (pdea) was purified from delftia acidovorans, the gene encoding the enzyme was cloned and expressed in escherichia coli, and the recombinant enzyme was purified to apparent homogeneity and characterized. pdea is an 85-kda trimer that exhibits maximal activity at 65 degrees c and ph 10 even though it was isolated from a mesophilic bacterium. although pdea exhibited both mono- and diesterase activity, it was most active on the phosphodiester bis(p-nitrophenyl)phosphate wi ...200312514034
[studies on the metabolism pathway of aniline degradation by comamonas acidovorans an3].all of the enzymes relating to aniline degradation in c. acidovorans an3 were inducible ones. when growing on aniline as sole carbon, nitrogen and energy sources, the cells of c. acidovorans an3 contained aniline dioxygenase, catechol-2, 3-dioxygenase, 2-hydromuconic semialdehyde dehydrogenase, 4-oxalocrotonic acid decarboxylase and 4-hydroxy-2-oxovalerate acid aldolase. the km and vmax of aniline dioxygenase were 292 mumol/l and 3.57 min-1, respectively. the km and vmax of catechol- ...199912555527
synergistic degradation of linuron by a bacterial consortium and isolation of a single linuron-degrading variovorax strain.the bacterial community composition of a linuron-degrading enrichment culture and the role of the individual strains in linuron degradation have been determined by a combination of methods, such as denaturing gradient gel electrophoresis of the total 16s rrna gene pool, isolation and identification of strains, and biodegradation assays. three strains, variovorax sp. strain wdl1, delftia acidovorans wdl34, and pseudomonas sp. strain wdl5, were isolated directly from the linuron-degrading culture. ...200312620840
purification and gene cloning of the oxygenase component of the terephthalate 1,2-dioxygenase system from delftia tsuruhatensis strain t7.the terephthalate 1,2-dioxygenase system (terdos) was found in cell extracts of delftia tsuruhatensis strain t7 (=ifo16741) grown in terephthalate-salt medium. the cell extract was separated by anion exchange chromatography to yield two fractions (r and z) that were necessary for oxygenation of terephthalate with nadh and fe(2+). the oxygenase component of terdos (terz) was purified from fraction z by gel filtration chromatography to near homogeneity. an alpha(3)beta(3) subunit structure was ded ...200312670689
mixed culture bioconversion of 16-dehydropregnenolone acetate to androsta-1,4-diene-3,17-dione: optimization of parameters.bioconversion of 16-dehydropregnenolone acetate (16-dpa) to androsta-1,4-diene-3,17-dione (add), an intermediate for the production of female sex hormones, by mixed culture of pseudomonas diminuta mtcc 3361 and comamonas acidovorans mtcc 3362 is reported. various physicochemical parameters for the bioconversion of 16-dpa to add have been optimized in shake flask cultures. nutrient broth inoculated with actively growing co-culture proved ideal for bacterial growth and bioconversion. a temperature ...200312675614
bacterial conversion of hydroxylamino aromatic compounds by both lyase and mutase enzymes involves intramolecular transfer of hydroxyl groups.hydroxylamino aromatic compounds are converted to either the corresponding aminophenols or protocatechuate during the bacterial degradation of nitroaromatic compounds. the origin of the hydroxyl group of the products could be the substrate itself (intramolecular transfer mechanism) or the solvent water (intermolecular transfer mechanism). the conversion of hydroxylaminobenzene to 2-aminophenol catalyzed by a mutase from pseudomonas pseudoalcaligenes js45 proceeds by an intramolecular hydroxyl tr ...200312732549
acidovorax valerianellae sp. nov., a novel pathogen of lamb's lettuce [valerianella locusta (l.) laterr].bacterial spot disease of lamb's lettuce [valerianella locusta (l.) laterr.] was first observed in fields in 1991. this new bacterial disease is localized in western france in high-technology field production of lamb's lettuce for the preparation of ready-to-use salad. nineteen strains isolated in 1992 and 1993 from typical black leaf spots of naturally infected lamb's lettuce were characterized and compared with reference strains of acidovorax and delftia. the pathogenicity of the 19 strains wa ...200312807202
multistep mechanism of chloride translocation in a strongly anion-selective porin channel.the strongly anion-selective porin channel omp32 from the bacterium delftia acidovorans differs from other unspecific porins by its pronounced selectivity for anions and its particularly small channel cross-section. multinanosecond molecular dynamics simulations of chloride ion movement in this pore protein suggest that translocated anions interact intimately with the charges of a "basic ladder", whose dynamics lead the anions in a stepwise manner through the constriction zone of the channel. th ...200312885642
ice from an ice machine is a potential source of bacterial contamination for hpc products -- implications for cell-processing facilities. 200312944241
a transposon encoding the complete 2,4-dichlorophenoxyacetic acid degradation pathway in the alkalitolerant strain delftia acidovorans p4a.the bacterial strain delftia acidovorans p4a, isolated from an extreme environment (heavily contaminated with organochlorines, highly alkaline conditions in an aqueous environment), was found to mineralize 2,4-dichlorophenoxyacetic acid (2,4-d) and 2-methyl-4-chlorophenoxyacetic acid under alkaline conditions. screening a genomic dna library of the alkalitolerant strain for 2,4-d genes revealed the presence of the two 2,4-d gene clusters tfdcdef and tfdc(ii)e(ii)bka, tfdr genes being located in ...200312949179
delftia tsuruhatensis sp. nov., a terephthalate-assimilating bacterium isolated from activated sludge.a terephthalate-assimilating bacterium was isolated from activated sludge collected from a domestic wastewater treatment plant in japan by enrichment with terephthalate as sole carbon source. the isolate, designated strain t7(t), was a gram-negative, short rod-shaped micro-organism. a phylogenetic study based on 16s rrna gene sequences indicated that strain t7(t) should be placed in the genus delftia: a dna-dna hybridization value of 69 % was determined between strain t7(t) and delftia acidovora ...200313130036
isolation and molecular characterization of thiosulfate-oxidizing bacteria from an italian rice field rice paddy soils an active cycling of sulfur compounds takes place. to elucidate the diversity of thiosulfate-oxidizing bacteria these organisms were enriched from bulk soil and rice roots by the most probable number method in liquid medium. from the mpn enrichment cultures 21 bacterial strains were isolated on solid mineral medium, and could be further shown to produce sulfate from thiosulfate. these strains were characterized by 16s rdna analyses. the isolates were affiliated to seven diffe ...200314529188
structure of haloacetate-catabolic incp-1beta plasmid puo1 and genetic mobility of its residing haloacetate-catabolic transposon.the self-transmissible plasmid puo1 from delftia acidovorans strain b carries two haloacetate-catabolic transposons, tnhad1 and tnhad2, and the mer genes for resistance to mercury. the complete 67,066-bp sequence of puo1 revealed that the mer genes were also carried by two tn402/tn5053-like transposons, tn4671 and tn4672, and that the puo1 backbone regions shared 99% identity to those of the archetype incp-1beta plasmid r751. comparison of puo1 with three other incp-1beta plasmids illustrated th ...200314594853
energization of comamonas testosteroni atcc 17454 for indicating toxic effects of chlorophenoxy herbicides.the toxicity of chlorophenoxy herbicides to a bacterium, strongly related to the well-known species delftia (formerly comamonas) acidovorans that are able to detoxify these xenobiotics, was investigated. the oxidation of n-hexanol via alcohol dehydrogenases, coupled with the generation of atp by electron transport phosphorylation (etp), was used as an indicator for energy-toxic effects on the growth of comamonas testosteroni atcc 17454. uncoupling--reductions in atp synthesis accompanied by incr ...200314674583
an extra large insertion in the polyhydroxyalkanoate synthase from delftia acidovorans ds-17: its deletion effects and relation to cellular proteolysis.the polyhydroxyalkanoate (pha) synthase (phac(da)) from delftia acidovorans ds-17 (formerly comamonas acidovorans) has a unique large insertion consisting of 40 amino acid residues in the alpha/beta hydrolase fold region. in order to examine whether this insertion is necessary for enzyme function, we generated a mutant gene where the nucleotides encoding the insertion sequence were deleted [phac(da)del(342-381)]. the ability of the mutant phac(da) lacking the insertion sequence to produce pha in ...200414769470
delftia acidovorans mc1 resists high herbicide concentrations--a study of nutristat growth on (rs)-2-(2,4-dichlorophenoxy)propionate and 2,4-dichlorophenoxyacetate.delftia acidovorans mc1 was continuously cultivated under nutristat conditions with elevated concentrations of the herbicides (rs)-2-(2,4-dichlorophenoxy)propionate [(rs)-2,4-dp] and 2,4-dichlorophenoxyacetate (2,4-d). the presence of 1-5 mm of either of these compounds did not essentially inhibit growth. moreover, substrate consumption was not essentially affected at ph values of 7.0-9.0 selected by reason of alkaline in situ conditions found e.g. on contaminated building rubble but was decreas ...200415056896
regulation of catabolic enzymes during long-term exposure of delftia acidovorans mc1 to chlorophenoxy herbicides.delftia acidovorans mc1 is able to grow on chlorophenoxy herbicides such as 2,4-dichlorophenoxypropionic acid (2,4-dcpp) and 2,4-dichlorophenoxyacetic acid as sole sources of carbon and energy. high concentrations of the potentially toxic organics inhibit the productive degradation and poison the organism. to discover the target of chlorophenoxy herbicides in d. acidovorans mc1 and to recognize adaptation mechanisms, the response to chlorophenoxy acids at the level of proteins was analysed. the ...200415073309
high phylogenetic diversity of transconjugants carrying plasmid pjp4 in an activated sludge-derived microbial community.transconjugants of plasmid pjp4, originating from an agar plate mating of a pseudomonas putida donor with an activated sludge-derived microbial community, were isolated and identified by partial 16s rdna sequencing. the transconjugant strains belonged to a variety of genera of the alpha-, beta-, gamabeta- and gamma-classes of the proteobacteria, mostly to the families rhizobiaceae and comamonadaceae and the genus stenotrophomonas. only p. putida and delftia spp. strains were able to grow on 2,4- ...200415183866
mineralization of individual congeners of linear alkylbenzenesulfonate by defined pairs of heterotrophic bacteria.parvibaculum lavamentivorans ds-1(t) utilized the commercial surfactant linear alkylbenzenesulfonate (las) (20 congeners with c(10) to c(13) side chains) as a carbon and energy source by shortening the side chain, and sulfophenylcarboxylates (spcs) and similar compounds (e.g., alpha,beta-unsaturated spcs [spc-2hs]) were excreted with quantitative recovery of the sulfophenyl moiety. 2-(4-sulfophenyl)decane (2-c10-las) was converted largely to 3-(4-sulfophenyl)butyrate (3-c4-spc), as were 2-c12-la ...200415240283
high-level expression and characterization of a highly functional comamonas acidovorans xanthine dehydrogenase in pseudomonas improved procedure is described for the high-level expression of comamonas acidovorans xdh in pseudomonas aeruginosa pao1-lac. the level of functional expression (56 mg protein/l culture) is found to be 7-fold higher than that observed in escherichia coli and 30-fold higher than that induced in c. acidovorans. co-expression of the xdhc gene is required for maximal level of functional expression. comparison of purified preparations of xdh expressed in the absence of xdhc (xdh(ab)) with that ex ...200415294283
localization and characterization of two novel genes encoding stereospecific dioxygenases catalyzing 2(2,4-dichlorophenoxy)propionate cleavage in delftia acidovorans mc1.two novel genes, rdpa and sdpa, encoding the enantiospecific alpha-ketoglutarate dependent dioxygenases catalyzing r,s-dichlorprop cleavage in delftia acidovorans mc1 were identified. significant similarities to other known genes were not detected, but their deduced amino acid sequences were similar to those of other alpha-ketoglutarate dioxygenases. rdpa showed 35% identity with taud of pseudomonas aeruginosa, and sdpa showed 37% identity with tfda of ralstonia eutropha jmp134. the functionally ...200415345421
emended description of the species lampropedia hyalina.three lampropedia hyalina strains from different habitats were compared by phenotypic, chemotaxonomic and molecular characteristics. all strains form coccoid cells and have been reported to grow as square tablets of eight to 64 cells. however, two of these strains (atcc 11041t and atcc 43383) have apparently lost this ability, and the third strain may temporarily lose this capacity under certain cultivation conditions. the three strains showed only minor differences in metabolic characteristics: ...200415388733
genetic analysis of phenoxyalkanoic acid degradation in sphingomonas herbicidovorans mh.phenoxyalkanoic acid degradation is well studied in beta- and gammaproteobacteria, but the genetic background has not been elucidated so far in alphaproteobacteria. we report the isolation of several genes involved in dichlor- and mecoprop degradation from the alphaproteobacterium sphingomonas herbicidovorans mh and propose that the degradation proceeds analogously to that previously reported for 2,4-dichlorophenoxyacetic acid (2,4-d). two genes for alpha-ketoglutarate-dependent dioxygenases, sd ...200415466552
microbial polyhydroxyalkanoates (phas): an emerging biomaterial for tissue engineering and therapeutic applications.among the various biomaterials available for tissue engineering and therapeutic applications, microbial polyhydroxyalkanoates (phas) offer the most diverse range of thermal and mechanical properties. of particular interest are the phas that contain 4-hydroxybutyrate such as poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [p(3hb-co-4hb) and poly(4-hydroxybutyrate) [p(4hb)]. these polyesters can only be synthesized by a few types of bacteria, among which comamonas acidovorans has the most efficient m ...200415468816
genes involved in aniline degradation by delftia acidovorans strain 7n and its distribution in the natural environment.aniline-degraders were isolated from activated sludge and environmental samples and classified into eight phylogenetic groups. seven groups were classified into gram-negative bacteria, such as acidovorax sp., acinetobacter sp., delftia sp., comamonas sp., and pseudomonas sp., suggesting the possible dominance of gram-negative aniline-degraders in the environment. aniline degradative genes were cloned from d. acidovorans strain 7n, and the nucleotide sequence of the 8,039-bp fragment containing e ...200415618615
characterization of a novel plant growth-promoting bacteria strain delftia tsuruhatensis hr4 both as a diazotroph and a potential biocontrol agent against various plant pathogens.a novel, plant growth-promoting bacterium delftia tsuruhatensis, strain hr4, was isolated from the rhizoplane of rice (oryza sativa l., cv. yueguang) in north china. in vitro antagonistic assay showed this strain could suppress the growth of various plant pathogens effectively, especially the three main rice pathogens (xanthomonas oryzae pv. oryzae, rhizoctonia solani and pyricularia oryzae cavara). treated with strain hr4 culture, rice blast, rice bacterial blight and rice sheath blight for cv. ...200515709367
[application of molecular systematics to study of bacterial cultures consuming volatile organic compounds].a range of species of four mixed bacterial cultures was studied by molecular systematics methods with the use of 16s rrna genes. the cultures had been developed for application in minireactors, to degrade volatile organic compounds (vocs): ethyl benzene, m-xylene, styrene, and o-xylene. a sample of 30 plasmid rdna clones was obtained for each of the mixed cultures. the clones were analyzed by rflp according to two restriction sites. major variants of the 16s-rdna sequences, corresponding to the ...200515859460
degradation of atrazine in a laboratory scale model system with danube river sediment.a laboratory-scale model system of danube river gravel bed was constructed. evaluation of water chemical parameters and composition of bacterial communities confirmed the liability of the model. degradation of atrazine, a frequent micropollutant of danube water was examined in the model system. in case of an acute atrazine load, short-term retention of the compound was observed, accumulation and degradation were not significant. long-term continuous dose of atrazine led to enhanced degradation o ...200515878028
evidence of pathogenic microbes in the international space station drinking water: reason for concern?molecular analyses were carried out on four preflight and six postflight international space station (iss)-associated potable water samples at various stages of purification, storage, and transport, to ascertain their associated microbial diversities and overall microbial burdens. following dna extraction, pcr amplification, and molecular cloning procedures, rdna sequences closely related to pathogenic species of acidovorax, afipia, brevundimonas, propionibacterium, serratia, and others were rec ...200415880908
bacterial ca2+ metabolism as the key to microbial carbonate precipitation.ca2+ -atpase enzymes facilitate active trans-membrane transport of ca2+ in micro-organisms. this study investigates the hypothesis that active calcium metabolism under conditions of alkaline stress is a key element of microbial carbonate precipitation, and that the latter plays an integral part in survival of bacteria under alkaline conditions.200115954580
purification, characterization, gene cloning and nucleotide sequencing of d: -stereospecific amino acid amidase from soil bacterium: delftia acidovorans.the d-amino acid amidase-producing bacterium was isolated from soil samples using an enrichment culture technique in medium broth containing d-phenylalanine amide as a sole source of nitrogen. the strain exhibiting the strongest activity was identified as delftia acidovorans strain 16. this strain produced intracellular d-amino acid amidase constitutively. the enzyme was purified about 380-fold to homogeneity and its molecular mass was estimated to be about 50 kda, on sodium dodecyl sulfate poly ...200515959727
genetic characterization of the poly(hydroxyalkanoate) synthases of various pseudomonas oleovorans strains.we identified the poly(hydroxyalkanoate) synthase (phas) genes of three strains of pseudomonas oleovorans by using polymerase chain reaction (pcr)-based detection methods. p. oleovorans nrrl b-14682 contains class i pha synthase gene (phac), nrrl b-14683 harbors class ii phac1 and phac2 genes, and nrrl b-778 contain both the class i and ii pha synthase genes. inverse-pcr and chromosomal walking techniques were employed to obtain the complete sequences of the class i phacs of nrrl b-778 (phbc778; ...200515968501
[molecular diversity and phylogenetic analysis of nitrogen-fixing (nifh) genes in alp prairie soil of sanjiangyuan natural reserve].research on the diversity of microorganism community in natural environment has been concerned hot spot using the newly molecular biotechnology in the world now. this was the first description of the molecular diversity and phylogenetic analysis of nitrogen-fixing (nifh) genes in alp prairie soil of sanjiangyuan natural reserve. dna was directly extracted from the soil microorganism and amplified the nifh gene fragment using pcr by the primers of nifh-34f 5'-aaagg(c/t)gg(a/t) atcgg(c/t)aa(a/g) t ...200515989253
isolation of soil bacteria adapted to degrade humic acid-sorbed phenanthrene.the goal of these studies was to determine how sorption by humic acids affected the bioavailability of polynuclear aromatic hydrocarbons (pahs) to pah-degrading microbes. micellar solutions of humic acid were used as sorbents, and phenanthrene was used as a model pah. enrichments from pah-contaminated soils established with nonsorbed phenanthrene yielded a total of 25 different isolates representing a diversity of bacterial phylotypes. in contrast, only three strains of burkholderia spp. and one ...200516000791
chromosome-encoded gene cluster for the metabolic pathway that converts aniline to tca-cycle intermediates in delftia tsuruhatensis ad9.delftia tsuruhatensis ad9 was isolated as an aniline-degrading bacterium from the soil surrounding a textile dyeing plant. the gene cluster involved in aniline degradation was cloned from the total dna of strain ad9 into escherichia coli jm109. after shotgun cloning, two recombinant e. coli strains showing aniline oxidation activity or catechol meta-cleavage activity were obtained by simple plate assays. these strains contained 9.3 kb and 15.4 kb dna fragments, respectively. sequence analysis of ...200516207925
[degradation of aniline by delftia tsuruhatensis 14s in batch and continuous processes].a delftia tsuruhatensis strain capable of consuming aniline as the sole source of carbon, nitrogen, and energy at concentrations of up to 3200 mg/l was isolated from activated sludge of purification works of oao volzhskii orgsintez. the strain grew on pyrocatechol and p-hydroxybenzoic acid, but did not consume phenol, 2-aminophenol, 3-chloroaniline, 4-chloroaniline, 2,3-dichloroaniline, 2,4-dichloroaniline, 3,4-dichloroaniline, 2-nitroaniline, 2-chlorophenol, or aminobenzoate. aniline is degrade ...200516240651
functional analysis of unique class ii insertion sequence is1071.various xenobiotic-degrading genes on many catabolic plasmids are often flanked by two copies of an insertion sequence, is1071. this 3.2-kb is element has long (110-bp) terminal inverted repeats (irs) and a transposase gene that are phylogenetically related to those of the class ii transposons. however, the transposition mechanism of is1071 has remained unclear. our study revealed that is1071 was only able to transpose at high frequencies in two environmental beta-proteobacterial strains, comamo ...200616391056
diversity and phylotype consistency of bacteria in the guts of three bee species (apoidea) at an oilseed rape field.the gut of insects may harbour one of the largest reservoirs of a yet unexplored microbial diversity. to understand how specific insects select for their own bacterial communities, the structural diversity and variability of bacteria found in the gut of different bee species was analysed. for three successive years, adults and larvae of apis mellifera ssp. carnica (honey bee), and bombus terrestris (bumble bee), as well as larvae of osmia bicornis (red mason bee) were collected at a flowering oi ...200616423014
high resolution crystal structures and molecular dynamics studies reveal substrate binding in the porin omp32.the porin omp32 is the major outer membrane protein of the bacterium delftia acidovorans. the crystal structures of the strongly anion-selective porin alone and in complex with the substrate malate were solved at 1.5 and 1.45 a resolution, respectively, and revealed a malate-binding motif adjacent to the channel constriction zone. binding is mediated by interaction with a cluster of two arginine residues and two threonines. this binding site is specific for omp32 and reflects the physiological a ...200616434398
degradation of fumonisin b1 by a bacterial strain isolated from soil.a mixed microbial culture degrading fumonisin b l was obtained from soil samples using an enrichment culture procedure. a bacterial isolate from the enrichment culture (strain ncb 1492) degraded fumonisin b1 after incubation for 3 h, as indicated by tlc and hplc analysis. on the basis of the sequence analysis of 16s rdna, strain ncb 1492 was related to the delftia/comamonas group. thin-layer chromatographic analysis indicated the presence of metabolites in the ncb 1492 culture filtrates after de ...200616453169
degradation of a plasticizer, di-n-butylphthalate by delftia sp. tbknp-05.a bacterial strain delftia sp. tbknp-05 isolated by para-hydroxybenzoate enrichment technique is capable of degrading di-n-butylphthalate (dbp) as a sole source of carbon and energy. analysis of intermediates by thin layer chromatography and high performance liquid chromatography indicated the presence of monobutylphthalate (mbp), phthalate (pa), and protocatechuate (pca). the washed cells grown on dbp and pa showed appreciable oxidation of dbp, mbp, pa, and pca. the enzyme activities in cell fr ...200616502295
degradation of plasticizer di-n-butylphthalate by delftia sp. tbknp-05.bacterial strain delftia sp. tbknp-05, isolated by para-hydroxybenzoate enrichment technique, is capable of degrading di-n-butylphthalate (dbp) as a sole source of carbon and energy. analysis of intermediates by thin-layer chromatography and high-performance liquid chromatography indicated the presence of monobutylphthalate (mbp), phthalate (pa), and protocatechuate (pca). the washed cells grown on dbp and pa showed appreciable oxidation of dbp, mbp, pa, and pca. the enzyme activities in cell-fr ...200616604416
2,4-dichlorophenoxyacetic acid (2,4-d) utilization by delftia acidovorans mc1 at alkaline ph and in the presence of dichlorprop is improved by introduction of the tfdk gene.growth of delftia acidovorans mc1 on 2,4-dichlorophenoxyacetic acid (2,4-d) and on racemic 2-(2,4-dichlorophenoxy)propanoic acid ((rs)-2,4-dp) was studied in the perspective of an extension of the strain's degradation capacity at alkaline ph. at ph 6.8 the strain grew on 2,4-d at a maximum rate (mu max) of 0.158 h(-1). the half-maximum rate-associated substrate concentration (ks) was 45 microm. at ph 8.5 mu max was only 0.05 h(-1) and the substrate affinity was mucher lower than at ph 6.8. the i ...200616715405
n-acetyltaurine dissimilated via taurine by delftia acidovorans nat.the naturally occurring sulfonate n-acetyltaurine was synthesized chemically and its identity was confirmed. aerobic enrichment cultures for bacteria able to utilize n-acetyltaurine as sole source of fixed nitrogen or as sole source of carbon were successful. one representative isolate, strain nat, which was identified as a strain of delftia acidovorans, grew with n-acetyltaurine as carbon source and excreted stoichiometric amounts of sulfate and ammonium. inducible enzyme activities were measur ...200616802176
evaluation of pyrrolidonyl arylamidase for the identification of nonfermenting gram-negative evaluate the activity of pyrrolidonyl arylamidase (pyr) for the differentiation and identification of nonfermenting gram negative rods (nfgnr), 293 isolates were tested. a 24 h culture of each test organism was prepared. from this a 108-109 cfu/ml suspension was added to 0.25 ml of sterile physiologic solution. a pyr disk was then added and the test was incubated for 30 minutes at 35-37 degrees c, at environmental atmosphere. reading was done by adding 1 drop of cinnamaldehyde reagent. strain ...200716822636
uptake kinetics of 2,4-dichlorophenoxyacetate by delftia acidovorans mc1 and derivative strains: complex characteristics in response to ph and growth substrate.the present investigation showed that active processes were involved in the uptake of 2,4-dichlorophenoxyacetate (2,4-d) by delftia acidovorans mc1. with 2,4-d-grown cells, uptake at ph 6.8 was highly affine and showed a complex pattern-forming intermediary plateau at 20-100 microm 2,4-d. the kinetics became increasingly sigmoidal with raising of the ph to 7.5 and 8.5, and complexity disappeared. the apparent maximum was obtained at around 400 microm 2,4-d at either ph, and amounted to 15-20 nmo ...200616861799
mineralization of paraoxon and its use as a sole c and p source by a rationally designed catabolic pathway in pseudomonas putida.organophosphate compounds, which are widely used as pesticides and chemical warfare agents, are cholinesterase inhibitors. these synthetic compounds are resistant to natural degradation and threaten the environment. we constructed a strain of pseudomonas putida that can efficiently degrade a model organophosphate, paraoxon, and use it as a carbon, energy, and phosphorus source. this strain was engineered with the pnp operon from pseudomonas sp. strain env2030, which encodes enzymes that transfor ...200617021221
bacterial diversity in aortic aneurysms determined by 16s ribosomal rna gene analysis.aortic aneurysms are common vascular conditions that cause considerable morbidity and mortality. understanding of the mechanisms involved in the pathogenesis of the condition remains limited. recently, infection has been suggested as possible contributor in the development of the disease. the aim of the present study was to examine aortic aneurysms for the presence of bacterial dna using polymerase chain reaction (pcr) targeting the 16s ribosomal rna (rrna) gene, followed by cloning and sequenci ...200617098542
detection and characterization of bacteria from the potato rhizosphere degrading n-acyl-homoserine lactone.quorum sensing plays a role in the regulation of soft rot diseases caused by the plant pathogenic bacterium pectobacterium carotovorum subsp. carotovorum. the signal molecules involved in quorum sensing in p. carotovorum subsp. carotovorum belong to the group of n-acyl homoserine lactones (ahls). in our study, we screened bacteria isolated from the potato rhizosphere for the ability to degrade ahls produced by p. carotovorum subsp. carotovorum. six isolates able to degrade ahls were selected for ...200617110970
in vitro biocompatibility evaluation of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) copolymer in fibroblast cells.among the various biomaterials available for tissue engineering and therapeutic applications, microbial polyhydroxyalkanoates offer the most diverse range of thermal and mechanical properties. in this study, the biocompatibility of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [p(3hb-co-4hb); containing 50 mol % of 4-hydroxybutyrate] copolymer produced by delftia acidovorans was evaluated. the cytotoxicity, mode of cell death, and genotoxicity of p(3hb-co-4hb) extract against v79 and l929 fibrobl ...200717120221
correlation of functional instability and community dynamics in denitrifying dispersed-growth reactors.understanding the relationship between microbial community dynamics and functional instability is an important step towards designing reliable biological water treatment systems. in this study, the community dynamics of two dispersed-growth denitrifying reactors were examined during periods of functional stability and instability. in both reactors during the period of functional instability, the effluent chemistry changed over time, with periods of high nitrate concentrations followed by periods ...200717142382
biosynthesis and native granule characteristics of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) in delftia acidovorans.the ability of delftia acidovorans to incorporate a broad range of 3-hydroxyvalerate (3hv) monomers into polyhydroxyalkanoate (pha) copolymers was evaluated in this study. poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [p(3hb-co-3hv)] containing 0-90 mol% of 3hv was obtained when a mixture of sodium 3-hydroxybutyrate and sodium valerate was used as the carbon sources. transmission electron microscopy analysis revealed an interesting aspect of the p(3hb-co-3hv) granules containing high molar ratios ...200717207850
selection of bacteria able to control fusarium oxysporum f. sp. radicis-lycopersici in stonewool substrate.tomato foot and root rot (tfrr), caused by fusariumoxysporum f. sp. radicis-lycopersici (forl), is an economically important disease of tomato. the aim of this study was to develop an efficient protocol for the isolation of bacteria, which controls tfrr based on selection of enhanced competitive root-colonizing bacteria from total rhizosphere soil samples.200717241352
high nitrogen removal from wastewater with several new aerobic bacteria isolated from diverse ecosystems.three new bacteria hs-03, hs-043 and hs-047 isolated from different ecosystems were found capable of aerobic denitrification. the potential application of these strains in wastewater treatment under aerobic conditions was investigated. these three bacteria all presented high nitrogen removal from wastewater that more than 98% of 10 mmol/l nitrate could be removed in 12-24 h by adding cheap external carbon source and low concentration of iron as well as molybdate. the mechanism at molecular level ...200617294651
isolation and characterization of delftia tsuruhatensis zjb-05174, capable of r-enantioselective degradation of 2,2-dimethylcyclopropanecarboxamide.r-enantioselective amidases are of considerable industrial interest due to potential applications in the production of optically active compounds. strain zjb-05174, capable of r-enantioselective degradation of 2,2-dimethylcyclopropanecarboxamide, was isolated employing a newly established colorimetric screening method. based on morphology, physiological tests, atb system (id 32 gn) and the 16s rrna sequence, this strain was identified as delftia tsuruhatensis. the intracellular amidase exhibited ...200717320353
mineralization of diuron [3-(3,4-dichlorophenyl)-1, 1-dimethylurea] by co-immobilized arthrobacter sp. and delftia acidovorans.mineralization of diuron has not been previously demonstrated despite the availability of some bacteria to degrade diuron into 3,4-dichloroaniline (3,4-dca) and others that can mineralize 3,4-dca. a bacterial co-culture of arthrobacter sp. n4 and delftia acidovorans w34, which respectively degraded diuron (20 mg l(-1)) to 3,4-dca and mineralized 3,4-dca, were able to mineralize diuron. total diuron mineralization (20 mg l(-1)) was achieved with free cells in co-culture. when the bacteria were im ...200717333465
enantioseparation and determination of 2,2-dimethylcyclopropanecarboxamide and corresponding acid in the bioconversion broth by gas chromatography.a simple and sensitive method employing gas chromatography was developed for the enantioseparation and determination of 2,2-dimethylcyclopropanecarboxamide and its acid in the bioconversion broth. samples were recovered in high yield by extracting the broth with equal volumes of ethyl acetate twice. separation of the four enantiomers was performed on a gamma-cyclodextrin based chiral column bgb-175. the effect of column flow rate and temperature on the retention and resolution of the enantiomers ...200717340564
metabolic activity and phylogenetic diversity of reed (phragmites australis) periphyton bacterial communities in a hungarian shallow soda the present study, the species composition and potential metabolic activities of bacterial communities of reed phragmites australis (cav.) (trin. ex steudel) periphyton from lake velencei were studied by cultivation-based and metabolic fingerprinting methods. serially diluted spring biofilm samples were used to test the community-level physiological profiling (clpp) using biolog microplates, and for plating onto different media. on the basis of their morphological, biochemical, and physiologi ...200717406774
antimicrobial properties of two purified skin peptides from the mink frog (rana septentrionalis) against bacteria isolated from the natural habitat.numerous peptides exhibiting antimicrobial properties have been isolated from the skins of many amphibian species. these peptides offer an innate chemical defense system against various microbial agents that exist in the amphibian's environment. amphibian skin peptides are typically tested for antimicrobial activity against microbial strains that are pathogenic to humans, but not on potential pathogenic or opportunistic bacteria that exist in the organism's habitat. two peptides, a brevinin-2-re ...200717499556
growth promotion of quorum-quenching bacteria in the rhizosphere of solanum tuberosum.among 17 molecules structurally related to n-acylhomoserine lactone (nahl), gamma-caprolactone (gcl), 6-caprolactone (6cl) and 4-heptanolide (htn) were found to stimulate the degradation of nahl by bacterial communities recovered from bulk and rhizospheric soils. in the 6cl-, gcl- and htn-treated bacterial consortia, the nahl-degrading bacteria were more abundant than in control (mannitol-treated) consortia. moreover, the gcl- and htn-consortia showed a biocontrol activity against pectobacterium ...200717504488
molecular characterization of class 3 integrons from delftia spp.two environmental strains, delftia acidovorans c17 and delftia tsuruhatensis a90, were found to carry class 3 integrons, which have seldom been reported and then only from pathogens in which they are associated with antibiotic resistance genes. the delftia integrons comprised a highly conserved class 3 integrase gene, upstream and oppositely oriented from a set of three or four gene cassettes that encoded unidentified functions. the a90 integron had one more gene cassette than the c17 integron, ...200717573473
characterization of efficient aerobic denitrifiers isolated from two different sequencing batch reactors by 16s-rrna adopting two sequencing batch reactors (sbrs) a and b, nitrate as the substrate, and the intermittent aeration mode, activated sludge was domesticated to enrich aerobic denitrifiers. the phs of reactor a were approximately 6.3 at dos 2.2-6.1 mg/l for a carbon source of 720 mg/l cod; the phs of reactor b were 6.8-7.8 at dos 2.2-3.0 mg/l for a carbon source of 1500 mg/l cod. both reactors maintained an influent nitrate concentration of 80 mg/l no3- -n. when the total inorganic nitrogen (tin) re ...200717630129
simultaneous mineralization of glyphosate and diuron by a consortium of three bacteria as free- and/or immobilized-cells formulations.a bacterial consortium able to mineralize two herbicides, glyphosate (pseudomonas 4asw) and diuron (arthrobacter sp. n4 and delftia acidovorans), was cultivated in both a synthetic culture medium without phosphate and a sediment extract medium. in the aim at optimizing glyphosate and diuron mineralization, all the combinations, i.e., free and/or immobilized cells in ca-alginate beads were tested. with the synthetic medium, the simultaneous mineralization of glyphosate and diuron required at leas ...200818026726
[microbial diversity in scorpion intestine (buthus martensii karsch)].scorpion is an important officinal animal, and has a high nutritional value. in this study, the culture-independent and culture-dependent methods were used to investigate the microbial diversity in the scorpion's intestine. results based on culture-independent method showed the bacteria to be related to alpha, beta, gamma-proteobacteria. bacteria isolated by the culture-dependent method were high g + c, gram-positive bacteria. the genera enterobacter, serratia and ochrobactrum were detected by b ...200718062268
diversity of nifh gene pools in the rhizosphere of two cultivars of sorghum (sorghum bicolor) treated with contrasting levels of nitrogen fertilizer.the diversity of nitrogen-fixing bacteria was assessed in the rhizospheres of two cultivars of sorghum (is 5322-c and ipa 1011) sown in cerrado soil amended with two levels of nitrogen fertilizer (12 and 120 kg ha(-1)). the nifh gene was amplified directly from dna extracted from the rhizospheres, and the pcr products cloned and sequenced. four clone libraries were generated from the nifh fragments and 245 sequences were obtained. most of the clones (57%) were closely related to nifh genes of un ...200818070072
bacterial sulfite dehydrogenases in organotrophic metabolism: separation and identification in cupriavidus necator h16 and in delftia acidovorans sph-1.the utilization of organosulfonates as carbon sources by aerobic or nitrate-reducing bacteria usually involves a measurable, uncharacterized sulfite dehydrogenase. this is tacitly assumed to be sulfite : ferricytochrome-c oxidoreductase [ec], despite negligible interaction with (eukaryotic) cytochrome c: the enzyme is assayed at high specific activity with ferricyanide as electron acceptor. purified periplasmic sulfite dehydrogenases (sorab, soxcd) are known from chemoautotrophic growth ...200818174144
comparative phylogenies of burkholderia, ralstonia, comamonas, brevundimonas and related organisms derived from rpob, gyrb and rrs gene sequences.phylogenetic analysis of strains from burkholderia, ralstonia, cupriavidus, comamonas, delftia, acidovorax, brevundimonas, herbaspirillum huttiense and "pseudomonas butanovora" was performed based on the protein-coding genes rpob and gyrb and on the 16s rrna-coding gene rrs. overall, the phylogenies deduced from the three genes were concordant among themselves and with current taxonomy. however, a few differences among individual gene phylogenies were noted. for example, the separation of cupria ...200818280706
[isolation, identification and characteristics of a phoxim-degrading bacterium xsp-1].a bacteria strain xsp-1 capable of utilizing phoxim as sole carbon source was isolated from sludge collected from a pesticide manufacturer. it was preliminarily identified as delftia sp. according to its physiological-biochemical analysis and the similarity analysis of its 16s rrna gene sequence (genbank accession no. ef061135). strain xsp-1 could degrade 100 mg/l phoxim within 7 h completely. the optimal ph and temperature for degradation were 7.0 and 35 degrees c respectively. the degrading ra ...200718290446
different bacterial strategies to degrade taurocholate.aerobic enrichment cultures with taurocholate or alkanesulfonates as sole sources of carbon and energy for growth were successful and yielded nine bacterial isolates, all of which utilized taurocholate. growth was complex and involved not only many, usually transient, excretion products but also sorption of taurocholate and cholate to cells. three metabolic strategies to dissimilate taurocholate were elucidated, all of which involved bile salt hydrolase cleaving taurocholate to cholate and tauri ...200818320171
experience of comamonas acidovorans keratitis with delayed onset and treatment response in immunocompromised report 2 cases of comamonas acidovorans keratitis in immunocompromised cornea.200818323706
identification of bacteria from the normal flora of perch, perca fluviatilis l., and evaluation of their inhibitory potential towards aeromonas species.pathogenic aeromonas sobria has been identified as a causative agent of ulcerative disease in farmed european perch, perca fluviatilis l. to study the effect of the normal intestinal bacterial flora of perch against a. sobria, we sampled 193 bacterial isolates from the perch digestive tract. the isolates were identified by sequence analysis of the 16s rrna gene and their inhibitory potential against a. sobria was evaluated in vitro. nineteen of the strains isolated showed inhibition and were als ...200818355180
effect of linear alkylbenzene sulfonates on the growth of aerobic heterotrophic cultivable bacteria isolated from an agricultural enrichment culture technique was used to isolate soil bacteria capable of growing in the presence of two different concentrations of linear alkylbenzene sulfonates (las) (10 and 500 microg ml(-1)). nine bacterial strains, representatives of the major colony types of aerobic heterotrophic cultivable bacteria in the enriched samples, were isolated and subsequently identified by pcr-amplification and partial sequencing of the 16s rrna gene. amongst the isolates, strains las05 (pseudomonas syring ...200818443905
a novel and complete gene cluster involved in the degradation of aniline by delftia sp. an3.a recombinant strain, escherichia coli jm109-an1, was obtained by constructing of a genomic library of the total dna of delftia sp. an3 in e. coli jm109 and screening for catechol 2,3-dioxygenase activity. this recombinant strain could grow on aniline as sole carbon, nitrogen and energy source. enzymatic assays revealed that the exogenous genes including aniline dioxygenase (ad) and catechol 2,3-dioxygenase (c230) genes could well express in the recombinant strain with the activities of ad and c ...200818763567
simple enrichment and independent cultures to expand bacterial community analysis from gedongsongo hot spring.denaturing gradient gel electrophoresis was used to identify bacterial communities from gedongsongo hot spring, indonesia, by culture-independent and -dependent procedures. predominant species were found to be closely related to beta-proteobacteria, particularly from genus ralstonia and delftia. other species present include alpha- and gamma-proteobacteria and thermus groups. some of the strains showed unique 16s rdna sequences.200818804068
mutagenic and clastogenic characterization of poststerilized poly(3-hydroxybutyrate-co-4-hydroxybutyrate) copolymer biosynthesized by delftia acidovorans.polyhydroxyalkanoates (pha) are naturally occurring biopolyesters that have great potential in the medical field. however, the leachables resulting from sterilization process of the biomaterials may exert toxic effect including genetic damage. here, we demonstrate that although gamma-irradiation of poly(3-hydroxybutyrate-co-50 mol % 4-hydroxybutyrate) [p(3hb-co-4hb)] did not cause any change in the morphology by scanning electron microscopy, there was a significant degradation of this copolymer ...200919051306
improvement of amidase production by a newly isolated delftia tsuruhatensis zjb-05174 through optimization of culture medium.the r-amidase production by a newly isolated strain of delftia tsuruhatensis zjb-05174 was optimized in this paper. effects of factors such as carbon sources, nitrogen sources, and inducers on amidase production were investigated. the medium composition was optimized using central composite designs and response surface analysis. the optimal medium components for enhanced amidase production were found to be as follows: glucose, 8.23 g/l; yeast extract, 11.59 g/l; 2,2-(r,s)-dimethylcyclopropane ca ...200819131696
in vitro potency of doripenem tested against an international collection of rarely isolated bacterial pathogens.doripenem, a new 1beta-methyl parenteral carbapenem, has very broad-spectrum activity against gram-positive and gram-negative aerobic bacteria. as noted here, the spectrum and potency extended to many rarely isolated species sampled by the doripenem global surveillance program. among the species or species groups with <or=0.14% prevalence (1959 strains tested), doripenem was active against 98.9% of enterobacteriaceae at <or=0.5 microg/ml. similarly, more than 90% of other rarely isolated gram-ne ...200919302927
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