| rapid identification of bacteria of the comamonadaceae with amplified ribosomal dna-restriction analysis (ardra). | ribosomal rrna gene fragments (rdna) encompassing the 16s rdna, the 16s-23s rdna spacer region and part of the 23s rdna of 95 strains belonging to 13 well-described taxa of the eubacterial family comamonadaceae (beta subclass of the proteobacteria or rrna superfamily iii) were enzymatically amplified using conserved primers. the fragments of approximately 2400 base pairs were subjected to restriction analysis. restriction fragment length patterns obtained with hinfi enabled us to distinguish 9 o ... | 1992 | 1354195 |
| transfer of several phytopathogenic pseudomonas species to acidovorax as acidovorax avenae subsp. avenae subsp. nov., comb. nov., acidovorax avenae subsp. citrulli, acidovorax avenae subsp. cattleyae, and acidovorax konjaci. | dna-rrna hybridizations, dna-dna hybridizations, polyacrylamide gel electrophoresis of whole-cell proteins, and a numerical analysis of carbon assimilation tests were carried out to determine the relationships among the phylogenetically misnamed phytopathogenic taxa pseudomonas avenae, pseudomonas rubrilineans, "pseudomonas setariae," pseudomonas cattleyae, pseudomonas pseudoalcaligenes subsp. citrulli, and pseudomonas pseudoalcaligenes subsp. konjaci. these organisms are all members of the fami ... | 1992 | 1371056 |
| identification of xenobiotic-degrading isolates from the beta subclass of the proteobacteria by a polyphasic approach including 16s rrna partial sequencing. | nineteen gram-negative, aerobic, biodegradative isolates were identified by using a polyphasic taxonomic approach. the presence of the specific polyamine 2-hydroxyputrescine and the presence of a ubiquinone with eight isoprenoid units in the side chain (ubiquinone q-8) allowed allocation of these organisms to the beta subclass of the proteobacteria. on the basis of the results of additional characterization experiments (i.e., api 20ne tests, determinations of soluble protein patterns, and dna-dn ... | 1992 | 1371062 |
| the major outer membrane protein of acidovorax delafieldii is an anion-selective porin. | the major outer membrane protein (omp34) of acidovorax delafieldii (formerly pseudomonas delafieldii) was purified to homogeneity and was characterized biochemically and functionally. the polypeptide has an apparent molecular weight (mr) of 34,000, and it forms stable oligomers at ph 9.0 in the presence of 10% octylpolyoxyethylene or 2% lithium dodecyl sulfate below 70 degrees c. the intact protein has a characteristic secondary structure composition, as revealed by fourier transforming infrared ... | 1991 | 1712013 |
| acidovorax, a new genus for pseudomonas facilis, pseudomonas delafieldii, e. falsen (ef) group 13, ef group 16, and several clinical isolates, with the species acidovorax facilis comb. nov., acidovorax delafieldii comb. nov., and acidovorax temperans sp. nov. | pseudomonas facilis and pseudomonas delafieldii are inappropriately assigned to the genus pseudomonas. they belong to the acidovorans rrna complex in rrna superfamily iii (i.e., the beta subclass of the proteobacteria). the taxonomic relationships of both of these species, two groups of clinical isolates (e. falsen [ef] group 13 and ef group 16), and several unidentified or presently misnamed strains were examined by using dna:rrna hybridization, numerical analyses of biochemical and auxanograph ... | 1990 | 2275854 |
| in situ biodegradation of poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) in natural waters. | the biodegradation of samples of poly(3-hydroxybutyrate)(p(3hb)), poly(3-hydroxybutyrate-co-10%-3-hydroxyvalerate)(p(3hb-co-10 %-3hv)), and poly 3-hydroxybutyrate-co-20%-3-hydroxyvalerate)(p(3hb-co-20%- 3hv)) was investigated in situ in natural waters. the degradation was studied by decrease in mass, molecular weight, and tensile strength. in two freshwater ponds the polymers were slowly degraded. after half a year of submersion the mass loss was less than 7%. after 358 days in a freshwater cana ... | 1995 | 7606659 |
| characterization by arbitrary primer polymerase chain reaction of polychlorinated biphenyl (pcb)-degrading strains of comamonas testosteroni isolated from pcb-contaminated soil. | in this study, we isolated and characterized biphenyl (bp) and polychlorinated biphenyl (pcb) degrading bacterial strains found in pcb-contaminated soil from an auto manufacturing plant located in syracuse, new york. twenty-one bp and pcb-degrading bacteria were randomly selected to form a representative sample of the bacterial population present at the site. of the 21 bacteria, 13 were identified as comamonas testosteroni, constituting about 60% of the bacterial population examined. other pcb d ... | 1995 | 7641143 |
| asymmetry of orientation and voltage gating of the acidovorax delafieldii porin omp34 in lipid bilayers. | the functional properties of the major outer-membrane protein of acidovorax delafieldii, the anion-selective porin omp34, were investigated in artificial membranes. detergent-solubilized porin incorporates into the membrane in a undirectional orientation solely determined by protein features. this enabled us to characterize the vectorial properties of the porin channels. omp34 is electrostatically asymmetric regarding both the ion conductivity of a single trimer and the macroscopic ion conductan ... | 1993 | 7680309 |
| detection and identification of phytopathogenic xanthomonas strains by amplification of dna sequences related to the hrp genes of xanthomonas campestris pv. vesicatoria. | three pairs of oligonucleotide primers specific for different regions of the hrp gene (hypersensitive reaction and pathogenicity) cluster of xanthomonas campestris pv. vesicatoria were designed and tested for amplification of dna isolated from a large number of different bacteria. dna sequences related to the hrp genes were successfully amplified from x. fragariae and from 28 pathovars of x. campestris. no dna amplification occurred with genomic dna from phytopathogenic strains of x. campestris ... | 1994 | 8017904 |
| characterization of bacteria isolated from a bleached kraft pulp mill wastewater treatment system. | water samples from the wastewater treatment system of a bleach kraft mill and from the river that supplies the mill were plated on six different media and culturable isolates were screened for substrate utilization patterns, taxonomic characters, plasmid content, and resistance to ampicillin, streptomycin, kanamycin, tetracycline, naldixic acid, mercury, nickel, copper, cobalt, cadmium, and zinc. a cluster analysis of the substrate utilization profiles and taxonomic characters revealed that pseu ... | 1993 | 8439869 |
| influence of earthworm activity on gene transfer from pseudomonas fluorescens to indigenous soil bacteria. | we have developed a model system to assess the influence of earthworm activity on the transfer of plasmid pjp4 from an inoculated donor bacterium, pseudomonas fluorescens c5t (pjp4), to indigenous soil microorganisms. three different earthworm species (lumbricus terrestris, lumbricus rubellus, and aporrectodea trapezoides), each with unique burrowing, casting, and feeding behaviors, were evaluated. soil columns were inoculated on the surface with 10(8) cells per g of soil of the donor bacterium, ... | 1996 | 8593052 |
| bacterial degradation of low concentrations of phenanthrene and inhibition by naphthalene | phenanthrene-degrading bacteria were isolated from enrichment cultures of soils contaminated with creosote and jet fuel. the isolates from the creosote enrichments were classified by fatty acid methyl ester profiles as acidovorax delafieldii and sphingomonas paucimobilis; the bacterium from the jet fuel-contaminated soil was not identified and was designated strain jfd11. all three isolates used phenanthrene as a sole carbon and energy source, and two of the isolates used fluoranthene as a sole ... | 1996 | 8661535 |
| characterization of bacterial communities from activated sludge: culture-dependent numerical identification versus in situ identification using group- and genus-specific rrna-targeted oligonucleotide probes | the structures of bacterial communities were studied in activated sludge samples obtained from the aerobic and anaerobic zones of a wastewater treatment plant showing enhanced phosphorous removal. samples were analyzed by in situ hybridization with oligonucleotide probes complementary to selected regions of the 16s and 23s ribosomal rna (rrna) characteristic for defined phylogenetic entities (genera and larger groups). the microbial community structures revealed by molecular techniques were comp ... | 1996 | 8688004 |
| biocidal activity in plant pathogenic acidovorax, burkholderia, herbaspirillum, ralstonia and xanthomonas spp. | antibacterial and antifungal activity was investigated for strains of acidovorax spp., burkholderia spp., herbaspirillum rubrisubalbicans and ralstonia solanacearum; strains representing 118 species and pathovars of xanthomonas were also tested for phytotoxic capacity. antibacterial activity was present in all burkholderia spp. except b. andropogonis, in biovars ii and iii of r. solanacearum but not in biovars i and iv, and in two strains of xanthomonas. little antibacterial activity was recorde ... | 1998 | 9633641 |
| voltage-dependent closing of porin channels: analysis of relaxation kinetics. | the anion-selective porin omp34 from acidovorax delafieldii was unidirectionally reconstituted in planar lipid membranes. pore closing was recorded particularly at low salt conditions for negative and positive membrane potentials in the range of +/-10 to +/-100 mv. relaxation curves were fitted by exponential functions in order to describe and to analyze the voltage-dependent behavior. omp34 exhibited the following characteristics: (i) the channels are asymmetric with respect to closing characte ... | 1998 | 9705978 |
| 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 ... | 1999 | 10319477 |
| genotypic diversity of acidovorax strains isolated from activated sludge and description of acidovorax defluvii sp. nov. | fluorescence in situ hybridization of activated sludge samples from a municipal wastewater treatment plant using oligonucleotide probes specific for acidovorax demonstrated that these bacteria are highly abundant in this environment. for the targeted cultivation of representatives belonging to this genus, isolates grown on agar plates after serial dilution were screened by whole-cell hybridization with specific probes. the obtained strains clustered in two phylogenetic groups as determined by 16 ... | 1999 | 10390871 |
| anaerobic mineralization of quaternary carbon atoms: isolation of denitrifying bacteria on dimethylmalonate. | the microbial capacity to degrade simple organic compounds with quaternary carbon atoms was demonstrated by enrichment and isolation of five denitrifying strains on dimethylmalonate as the sole electron donor and carbon source. quantitative growth experiments showed a complete mineralization of dimethylmalonate. according to phylogenetic analysis of the complete 16s rrna genes, two strains isolated from activated sewage sludge were related to the genus paracoccus within the alpha-proteobacteria ... | 1999 | 10427013 |
| differential detection of key enzymes of polyaromatic-hydrocarbon-degrading bacteria using pcr and gene probes. | bacteria with ability to degrade polyaromatic hydrocarbons (pahs), isolated from wastewater and soil samples, were investigated for their taxonomic, physiological and genetic diversity. eighteen isolates able to metabolize naphthalene or phenanthrene as sole carbon source were taxonomically affiliated to different subclasses of the proteobacteria (sphingomonas spp., acidovorax spp., comamonas spp. and pseudomonas spp.) and to phyla of gram-positive bacteria with low and high dna g + c content (p ... | 1999 | 10439412 |
| microbial degradation of nitrobenzene and mono-nitrophenol by bacteria enriched from municipal activated sludge. | using a mixture of three mono nitrophenols as sole carbon, nitrogen and energy sources, mixed cultures were enriched from municipal activated sludge to degrade both nitrophenols and nitrobenzene. bacterial growth and degradation rate could be increased by supplementing the medium with 0.1% ye. microorganisms were isolated from the nitrophenols enrichment, and they were identified as strains of comamonas testosteroni and acidovorax delafieldii. these strains showed broad degradation ability towar ... | 1999 | 10446720 |
| degradation of phenanthrene by different bacteria: evidence for novel transformation sequences involving the formation of 1-naphthol. | four polycyclic aromatic hydrocarbon (pah)-degrading bacteria, namely arthrobacter sulphureus rkj4, acidovorax delafieldii p4-1, brevibacterium sp. hl4 and pseudomonas sp. dlc-p11, capable of utilizing phenanthrene as the sole source of carbon and energy, were tested for its degradation using radiolabelled phenanthrene. [9-14c]phenanthrene was incubated with microorganisms containing 100 mg/l unlabelled phenanthrene and the evolution of 14co2 was monitored: within 18 h of incubation, 30.1, 35.6, ... | 1999 | 10645629 |
| acidovorax anthurii sp. nov., a new phytopathogenic bacterium which causes bacterial leaf-spot of anthurium. | the bacterial leaf-spot of anthurium emerged during the 1980s, in the french west indies and trinidad. this new bacterial disease is presently wide spread and constitutes a serious limiting factor for commercial anthurium production. twenty-nine strains isolated from leaf-spots of naturally infected anthurium were characterized and compared with reference strains belonging to the comamonadaceae family, the genera ralstonia and burkholderia, and representative fluorescent pseudomonads. from artif ... | 2000 | 10826809 |
| properties of a bacterium which degrades solid poly(tetramethylene succinate)-co-adipate, a biodegradable plastic. | various microorganisms were screened for their ability to degrade poly(tetramethylene succinate)-co-(tetramethylene adipate) (pbsa). strain bs-3, which was newly isolated from a soil sample, was selected as the best strain. from taxonomical studies, the strain was tentatively ascribed to belong to the genus acidovorax, most probably to the species a. delafieldii. strain bs-3 could degrade both solid and emulsified pbsa, and also emulsified poly(tetramethylene succinate). during the degradation, ... | 2000 | 10913861 |
| isolation and characterization of diverse halobenzoate-degrading denitrifying bacteria from soils and sediments. | denitrifying bacteria capable of degrading halobenzoates were isolated from various geographical and ecological sites. the strains were isolated after initial enrichment on one of the monofluoro-, monochloro-, or monobromo-benzoate isomers with nitrate as an electron acceptor, yielding a total of 33 strains isolated from the different halobenzoate-utilizing enrichment cultures. each isolate could grow on the selected halobenzoate with nitrate as the terminal electron acceptor. the isolates obtai ... | 2000 | 10919805 |
| polyphasic characterization of poly-3-hydroxybutyrate-co-3-hydroxyvalerate (p(hb-co-hv)) metabolizing and denitrifying acidovorax sp. strains. | for the purpose of denitrification in small drinking water plants, a bacterial mixed population was isolated from a packed bed column bioreactor with poly-3-hydroxybutyrate-co-3-hydroxyvalerate (p(hb-co-hv)) as a substrate for the denitrification of ground water (10 degrees c). isolates 2niii from the mixed culture, with the ability to denitrify and metabolize p(hb-co-hv), were used as starter cultures for the elimination of nitrate in ground water. the strains were characterized by diverse tech ... | 2000 | 11108015 |
| alpha- and beta-proteobacteria control the consumption and release of amino acids on lake snow aggregates. | we analyzed the composition of aggregate (lake snow)-associated bacterial communities in lake constance from 1994 until 1996 between a depth of 25 m and the sediment surface at 110 m by fluorescent in situ hybridization with rrna-targeted oligonucleotide probes of various specificity. in addition, we experimentally examined the turnover of dissolved amino acids and carbohydrates together with the microbial colonization of aggregates formed in rolling tanks in the lab. generally, between 40 and m ... | 2001 | 11157226 |
| characterization of maize cytochrome p450 monooxygenases induced in response to safeners and bacterial pathogens. | plants use a diverse array of cytochrome p450 monooxygenases in their biosynthetic and detoxification pathways. to determine the extent to which various maize p450s are induced in response to chemical inducers, such as naphthalic anhydride (na), triasulfuron (t), phenobarbital, and bacterial pathogens (erwinia stuartii, acidovorax avenae), we have analyzed the response patterns of seven p450 transcripts after treatment of seedlings with these inducers. each of these p450 transcripts has distinct ... | 2001 | 11161067 |
| retention of water-borne bacteria by membrane filters. part iii: bacterial challenge tests on 0.1 micron rated filters. | clear performance differences were observed between different 0.1 micron rated filters in terms of their microbial removal efficiency when challenged with naturally occurring waterborne bacteria from a water source. penetration occurred with three 0.1 micron rated "sterilizing grade" filter types tested, from three different filter manufacturers, that did not have a specific high titer reduction claim for acholeplasma laidlawii. bacteria shown to penetrate these 0.1 micron rated filters were qui ... | 2001 | 11310317 |
| retention of water-borne bacteria by membrane filters. part ii: scanning electron microscopy (sem) and fatty acid methyl ester (fame) characterization of bacterial species recovered downstream of 0.2/0.22 micron rated filters. | the results of scanning electron microscopic (sem) and fatty acid methyl ester (fame) characterization of the bacterial species shown to penetrate conventional 0.2/0.22 micron rated "sterilizing grade" filters are presented. sem data suggest that retention of bacteria by these filters appears to be strongly influenced by the morphology, and especially the width of bacteria and less so by length. when the bacterial cell width is small, less than 0.3 micron or so, the cell length does not appear t ... | 2001 | 11310323 |
| evaluation of the denitrifying microbiota of anoxic reactors. | removal of inorganic nitrogen compounds from wastewaters can be accomplished by a combination of the biological processes of nitrification and denitrification. the information on the microbiota present in denitrifying reactors is still scarce. in the present work the evaluation of the denitrifying microbiota of different reactor sludges was performed by specific activity measurements and mpn count of denitrifiers. we also present the isolation and physiological and phylogenetic characterisation ... | 2001 | 11311436 |
| denitrification with acrylonitrile as a substrate using pure bacteria cultures isolated from acrylonitrile-butadiene-styrene wastewater. | this study attempted to isolate and identify the denitrifying bacteria that utilize acrylonitrile as a substrate from acrylonitrile-butadiene-styrene (abs) resin wastewater. the performance of the denitrifying bacteria for treating different initial acrylonitrile concentrations was also investigated under anoxic conditions. the results showed that seven strains of denitrifying bacteria that can use acrylonitrile or acrylic acid as a substrate were isolated from the denitrification tank of a wast ... | 2001 | 11341291 |
| identity and potential functions of heterotrophic bacterial isolates from a continuous-upflow fixed-bed reactor for denitrification of drinking water with bacterial polyester as source of carbon and electron donor. | a collection of 186 heterotrophic bacteria, isolated directly from a continuous-upflow fixed-bed reactor for the denitrification of drinking water, in which poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (phbv) granules acted as biofilm carrier, carbon source and electron donor, was studied with regard to taxonomic affiliation and degradation and denitrification characteristics. two granule samples were taken from a fully operating reactor for enumeration and isolation of heterotrophic bacteria. o ... | 2001 | 11518336 |
| relationships between microbial community structure and hydrochemistry in a landfill leachate-polluted aquifer. | knowledge about the relationship between microbial community structure and hydrogeochemistry (e.g., pollution, redox and degradation processes) in landfill leachate-polluted aquifers is required to develop tools for predicting and monitoring natural attenuation. in this study analyses of pollutant and redox chemistry were conducted in parallel with culture-independent profiling of microbial communities present in a well-defined aquifer (banisveld, the netherlands). degradation of organic contami ... | 2001 | 11571165 |
| xenophilus azovorans gen. nov., sp. nov., a soil bacterium that is able to degrade azo dyes of the orange ii type. | the taxonomy of strain kf46ft, which was isolated previously after an aerobic enrichment with the azo compound 1-(4'-carboxyphenylazo)-2-naphthol as the sole source of energy and carbon, was investigated by a polyphasic approach. the organism contained a quinone system with ubiquinone q-8 and 2-hydroxyputrescine and putrescine as the major polyamines, suggesting that strain kf46ft belonged to the beta-subclass of the proteobacteria. the polar lipid profile consisted mainly of phosphatidylethanol ... | 2001 | 11594616 |
| cellular fatty acid composition of lautropia mirabilis. | ten strains of lautropia mirabilis (atcc 51599(t) and nine phenotypically similar clinical isolates) were examined for cellular fatty acid (cfa) composition to evaluate their chemical relatedness to known bacterial species and groups. the cfas were liberated from whole cells by base hydrolysis, methylated, and analyzed by gas-liquid chromatography. cfa profiles were generated by using a commericial software package (midi, newark, del.). all strains tested had an identical cfa profile characteriz ... | 2001 | 11682548 |
| method for qualifying microbial removal performance of 0.1 micron rated filters. part i: characterization of water isolates for potential use as standard challenge organisms to qualify 0.1 micron rated filters. | although 0.1 microm rated filters intended for pharmaceutical sterilization applications have been commercially available for at least 15 years, there is no industry-wide standard for qualifying the microbial removal performance of these filters. in this article, we report on the bacterial challenge methodology used to screen four bacterial species for potential utility as a standard challenge organism to qualify 0.1 microm rated filters. these isolates were, in their natural state, demonstrated ... | 2001 | 11766822 |
| relationships within the proteobacteria of plant pathogenic acidovorax species and subspecies, burkholderia species, and herbaspirillum rubrisubalbicans by sequence analysis of 16s rdna, numerical analysis and determinative tests. | sequence data for 16s rdna of the type strains of acidovorax avenae subsp. avenae, a. avenae subsp. cattleyae, a. avenae subsp. citrulli, a. konjaci and herbaspirillum rubrisubalbicans were compared with genbank library accessions of burkholderia spp., comamonas sp., ralstonia solanacearum and variovorax sp. maximum parsimony analysis produced two clusters: 1. acidovorax spp., comamonas sp., and variovorax sp. (all in the comamonadaceae), and 2. burkholderia spp., ralstonia solanacearum, and her ... | 2001 | 11827206 |
| cloning and sequencing of an intracellular d(-)-3-hydroxybutyrate oligomer hydrolase from acidovorax sp. strain sa1 and purification of the enzyme. | the gene of an intracellular d(-)-3-hydroxybutyrate oligomer hydrolase (i3hboh) was cloned and sequenced from a poly(3-hydroxybutyrate) (phb)-degrading bacterium, acidovorax sp. strain sa1. the i3hboh gene has 876 nucleotides corresponding to the deduced sequence of 292 amino acids. in this amino acid sequence, the general lipase box sequence (g-x(1)-s-x(2)-g) was found, whose serine residue was determined to the active sites serine by site-directed mutagenesis. an i3hboh was purified to electro ... | 2002 | 12070691 |
| enzymatic hydrolysis of bacterial poly(3-hydroxybutyrate-co-3-hydroxypropionate)s by poly(3-hydroxyalkanoate) depolymerase from acidovorax sp. tp4. | enzymatic degradability has been investigated for a series of bacterial poly(3-hydroxybutyrate-co-3-hydroxypropionate)s (p(3hb-co-3hp)s) with 3-hydroxypropionate (3hp) unit contents from 11 to 86 mol % as well as poly(3-hydroxybutyrate) (p(3hb)) and chemosynthesized poly(3-hydroxypropionate) (p(3hp)). the behavior of degradation by two types of extracellular poly(3-hydroxyalkanoate) (pha) depolymerases purified from ralstonia pikettii t1 and acidovorax sp. tp4, defined respectively as pha depoly ... | 2002 | 12099829 |
| enzymatic hydrolysis of chemosynthesized atactic poly(3-hydroxybutyrate) by poly(3-hydroxyalkanoate) depolymerase from acidovorax sp. tp4 and ralstonia pickettii t1. | the enzymatic degradability of chemosynthesized atactic poly([r,s]-3-hydroxybutyrate) [a-p(3hb)] by two types of extracellular poly(3-hydroxyalkanoate) (pha) depolymerases purified from ralstonia pickettii t1 (phaz(ral)) and acidovorax sp. tp4 (phaz(aci)), defined respectively as pha depolymerase types i and ii according to the position of the lipase box in the catalytic domain, were studied. the enzymatic degradation of a-p(3hb) by phaz(aci) depolymerase was confirmed from the results of weight ... | 2002 | 12217032 |
| degradation of polycyclic aromatic hydrocarbons at low temperature under aerobic and nitrate-reducing conditions in enrichment cultures from northern soils. | the potential for biodegradation of polycyclic aromatic hydrocarbons (pahs)at low temperature and under anaerobic conditions is not well understood, but such biodegradation would be very useful for remediation of polluted sites. biodegradation of a mixture of 11 different pahs with two to five aromatic rings, each at a concentration of 10 micro g/ml, was studied in enrichment cultures inoculated with samples of four northern soils. under aerobic conditions, low temperature severely limited pah b ... | 2003 | 12514005 |
| the influence of the chemical composition of drinking water on cuprosolvency by biofilm bacteria. | this study investigated the influence of water chemistry on copper solvation (cuprosolvency) by pure culture biofilms of heterotrophic bacteria isolated from copper plumbing. | 2003 | 12588559 |
| anaerobic mineralization of quaternary carbon atoms: isolation of denitrifying bacteria on pivalic acid (2,2-dimethylpropionic acid). | the degradability of pivalic acid was established by the isolation of several facultative denitrifying strains belonging to zoogloea resiniphila, to thauera and herbaspirillum, and to comamonadaceae, related to [aquaspirillum] and acidovorax, and of a nitrate-reducing bacterium affiliated with moraxella osloensis. pivalic acid was completely mineralized to carbon dioxide. the catabolic pathways may involve an oxidation to dimethylmalonate or a carbon skeleton rearrangement, a putative 2,2-dimeth ... | 2003 | 12620885 |
| purification, cloning, sequencing and over-expression in escherichia coli of a regioselective aliphatic nitrilase from acidovorax facilis 72w. | a regioselective aliphatic nitrilase from acidovorax facilis 72w was purified and characterized, and the corresponding gene was cloned and sequenced. this nitrilase gene was over-expressed in escherichia coli, generating a microorganism that efficiently and regioselectively catalyzes the conversion of aliphatic dinitriles to cyanocarboxylic acids. the high yields obtained, mild reaction conditions used, and robustness observed make this biocatalyst suitable for industrial applications. | 2003 | 12655453 |
| ramlibacter tataouinensis gen. nov., sp. nov., and ramlibacter henchirensis sp. nov., cyst-producing bacteria isolated from subdesert soil in tunisia. | ramlibacter gen. nov. is proposed for two aerobic, chemo-organotrophic, cyst-producing soil bacterial strains. these bacteria are gram-negative, non-flagellated rods or cysts, isolated from subdesert soil in tataouine, tunisia. phylogenetic analyses of the rrs sequences of the two strains showed that they do not constitute a robust clade at the genus level with any previously described bacteria and that they are a deep branch of a clade also grouping the genera acidovorax and hydrogenophaga with ... | 2003 | 12710631 |
| flagellin from an incompatible strain of acidovorax avenae mediates h2o2 generation accompanying hypersensitive cell death and expression of pal, cht-1, and pbz1, but not of lox in rice. | acidovorax avenae causes a brown stripe disease in monocot plants. we recently reported that a rice-incompatible strain of a. avenae caused hypersensitive cell death in rice and that the flagellin of the incompatible strain was involved in this response. the incompatible strain induced the rapid generation of h2o2 accompanying hypersensitive cell death and the expression of defense genes such as pal, cht-1, pbz1, and lox, whereas the compatible strain did not. the purified incompatible flagellin ... | 2003 | 12744513 |
| 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 ... | 2003 | 12807202 |
| expression of the nitroarene dioxygenase genes in comamonas sp. strain js765 and acidovorax sp. strain js42 is induced by multiple aromatic compounds. | this work reports a genetic analysis of the expression of nitrobenzene dioxygenase (nbdo) in comamonas sp. strain js765 and 2-nitrotoluene dioxygenase (2ntdo) in acidovorax sp. strain js42. strains js765 and js42 possess identical lysr-type regulatory proteins, nbzr and ntdr, respectively. nbzr/ntdr is homologous to nahr, the positive salicylate-responsive transcriptional activator of the naphthalene degradation genes in pseudomonas putida g7. the genes encoding nbdo and 2ntdo in each strain are ... | 2003 | 12813084 |
| determination of in situ bacterial growth rates in aquifers and aquifer sediments. | laboratory and field-scale studies with stained cells were performed to monitor cell growth in groundwater systems. during cell division, the fluorescence intensity of the protein stain 5-(and 6-)-carboxyfluorescein diacetate succinimidyl ester (cfda/se) for each cell is halved, and the intensity can be tracked with a flow cytometer. two strains of bacteria, comamonas sp. strain da001 and acidovorax sp. strain oy-107, both isolated from a shallow aquifer, were utilized in this study. the change ... | 2003 | 12839747 |
| acidovorax-like symbionts in the nephridia of earthworms. | dense accumulations of bacteria in the excretory organs, nephridia, were first described more than 75 years ago in members of the annelid family lumbricidae (earthworms). these nephridial symbionts were assumed to play a role in the degradation of proteins in the excretory fluid for nitrogen recycling. in the present study, the phylogenetic affiliation of the nephridial bacteria of the earthworms lumbricus terrestris, aporrectodea tuberculata, octolasion lacteum and eisenia foetida was resolved. ... | 2003 | 12919416 |
| stability of the bacterial community in a pulp mill effluent treatment system during normal operation and a system shutdown. | currently, very little is known about the normal dynamics of microbial populations in wastewater treatment systems and the relationship between population dynamics and functional stability of treatment systems. we monitored the bacterial community in an oxygen activated sludge system at a pulp and paper mill during a 55-day period that included normal operation as well as an 11-day shutdown of the system and the subsequent start-up. ribosomal intergenic spacer (ris) length polymorphism fingerpri ... | 2003 | 14604633 |
| microbial degradation of chlorobenzene under oxygen-limited conditions leads to accumulation of 3-chlorocatechol. | five bacterial strains (acidovorax facilis b517, cellulomonas turbata b529, pseudomonas veronii b547, pseudomonas veronii b549, and paenibacillus polymyxa b550) isolated on chlorobenzene as the sole source of carbon and energy were screened for the accumulation of the putative metabolic intermediate 3-chlorocatechol during growth on chlorobenzene under oxygen-limited conditions in the presence and absence of nitrate (1 mm). 3-chlorocatechol accumulated in the growth media of all five strains, bu ... | 2004 | 14982371 |
| application of a vital fluorescent staining method for simultaneous, near-real-time concentration monitoring of two bacterial strains in an atlantic coastal plain aquifer in oyster, virginia. | two differentially labeled bacterial strains were monitored in near-real time during two field-scale bacterial transport experiments in a shallow aquifer in july 2000 and july 2001. comamonas sp. strain da001 and acidovorax sp. strain oy-107 were grown and labeled with the vital fluorescent stain tamra/se (5 [and -6]-carboxytetramethylrhodamine, succinimidyl ester) or cfda/se (5 [and -6]-carboxyfluorescein diacetate, succinimidyl ester). fluorescently labeled cells and a conservative bromide tra ... | 2004 | 15006793 |
| a rapid method for the determination of metal toxicity to the biodegradation of water insoluble polymers. | a rapid and inexpensive test has been developed to investigate the influence of elevated heavy metal concentrations on the degradation of biodegradable plastics. using an overlay agar technique it could be demonstrated that copper concentrations above 8 to 14 mg/l inhibit the degradation of powdered poly(3-hydroxybutyrate), (phb), by acidovorax delafieldii. this is the first study demonstrating the inhibiting influence of metals on the biodegradation of phb. | 1996 | 15067488 |
| roles of poly(3-hydroxybutyrate) depolymerase and 3hb-oligomer hydrolase in bacterial phb metabolism. | many poly-3-hydroxybutyrate (phb)-degrading enzymes have been studied. but biological roles of 3hb-oligomer hydrolases (3hbohs) and how phb depolymerases (phbdps) and 3hbohs cooperate in phb metabolism are not fully elucidated. in this study, several phbdps and 3hbohs from three types of bacteria were purified, and their substrate specificity, kinetic properties, and degradation products were investigated. from the results, phbdp and 3hboh seemed to play a role in phb metabolism in three types o ... | 2004 | 15170237 |
| removal of nitriles from synthetic wastewater by acrylonitrile utilizing bacteria. | this study describes the ability of two bacteria strains, isolated from an abs resin manufacturing wastewater treatment system, to remove high acrylonitrile concentrations. straight chain aliphatic nitrile compound (propionitrile, allyl cyanide); branch chain aliphatic nitrile compound (isobutyronitrilc) and aromatic nitrile compound (benzonitrile) removal by comamonas testosteroni and acidovorax sp. was also investigated. the results are: comamonas testosteroni and acidovorax sp. can remove acr ... | 2004 | 15242125 |
| microbiological influences in 'blue water' copper corrosion. | to investigate the influence of micro-organisms associated with copper corrosion on 'blue water' corrosion in drinking water. | 2004 | 15281940 |
| improved laboratory diagnosis of bacterial and fungal infections in patients with hematological malignancies using pcr and ribosomal rna sequence analysis. | during october 1999 to november 2000, 98 blood culture specimens from the same number of febrile episodes originating from 49 patients with hematological malignancies were examined for the presence of eubacteria and fungi based on 16s rrna gene and the 5.8, 18 and 28s rrna combined with in vitro pcr amplification and sequencing, in addition to conventional blood culture laboratory techniques. nineteen of the samples were associated with positive blood cultures. eubacterial (16s rrna) pcr detecte ... | 2004 | 15370218 |
| rice cdna microarray-based gene expression profiling of the response to flagellin perception in cultured rice cells. | incompatible strains of acidovorax avenae elicit an immune response in cultured rice cells, with immunity specifically induced by the flagellin of the incompatible strain. to identify genes regulated by flagellin perception signaling in cultured rice cells, gene expression patterns were analyzed with rice cdna microarrays, including 3,353 independent rice cdna clones. in all, 131 genes were differentially expressed between incompatible and compatible interactions. k-means clustering showed that ... | 2004 | 15384489 |
| 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: ... | 2004 | 15388733 |
| bacterial diversity of a soil sample from schirmacher oasis, antarctica. | the bacterial diversity of a soil sample collected in the vicinity of lake zub, schirmacher oasis, antarctica, was determined both by establishing pure colonies of culturable bacteria and by cloning the total 16s rdna of the soil and establishing the phylogeny of the clones. analysis of the 16s rrna gene clones indicated that the bacteria belonged to the classes alpha-proteobacteria, beta-proteobacteria, gamma-proteobacteria, gemmatimonas, bacteriodetes, actinobacteria, chloroflexi and chlamydia ... | 2004 | 15559969 |
| 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 ... | 2004 | 15618615 |
| stable-isotope probing of bacteria capable of degrading salicylate, naphthalene, or phenanthrene in a bioreactor treating contaminated soil. | [13c6]salicylate, [u-13c]naphthalene, and [u-13c]phenanthrene were synthesized and separately added to slurry from a bench-scale, aerobic bioreactor used to treat soil contaminated with polycyclic aromatic hydrocarbons. incubations were performed for either 2 days (salicylate, naphthalene) or 7 days (naphthalene, phenanthrene). total dna was extracted from the incubations, the "heavy" and "light" dna were separated, and the bacterial populations associated with the heavy fractions were examined ... | 2005 | 15746319 |
| genetic diversity of benzoyl coenzyme a reductase genes detected in denitrifying isolates and estuarine sediment communities. | benzoyl coenzyme a (benzoyl-coa) reductase is a central enzyme in the anaerobic degradation of organic carbon, which utilizes a common intermediate (benzoyl-coa) in the metabolism of many aromatic compounds. the diversity of benzoyl-coa reductase genes in denitrifying bacterial isolates capable of degrading aromatic compounds and in river and estuarine sediment samples from the arthur kill in new jersey and the chesapeake bay in maryland was investigated. degenerate primers were developed from t ... | 2005 | 15812036 |
| regulation of pyrimidine biosynthesis in acidovorax delafieldii. | the regulation of de novo pyrimidine biosynthesis in the nutritionally versatile bacterium acidovorax delafieldii atcc 17505t was influenced by carbon source and pyrimidine supplementation. uracil supplementation of succinate-grown a. delafieldii atcc 17505t cells produced a greater decrease in the de novo pyrimidine biosynthetic pathway enzyme activities than did orotic acid supplementation. the presence of orotic acid or uracil in the medium of the glucose-grown wild type cells generally incre ... | 2005 | 15812862 |
| functional and compositional comparison of two activated sludge communities remediating coking effluent. | the success of engineered microbiological systems is evident in the global application of activated sludge communities to remediate coking effluent. however, there is a lack of understanding of the microbiology underlying treatment efficiency and stability. in this study, two functionally distinct activated sludge pools, treating the same effluent and operating under the same conditions, were examined to establish a relationship between overall diversity and/or functional diversity with respect ... | 2005 | 15819853 |
| 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 ... | 2004 | 15880908 |
| differential rhizosphere establishment and cyanide production by alginate-formulated weed-deleterious rhizobacteria. | the effects of pseudomonas putida ath2-1ri/9 and acidovorax delafieldii ath2-2rs/1 on rhizosphere colonization, cyanide production, and growth of velvetleaf and corn was examined. when formulated in alginate beads and inoculated onto velvetleaf and corn plants (10(9) cfu/plant), only p. putida ath2-1ri/9 consistently reduced velvetleaf growth. neither isolate inhibited corn growth. interestingly the levels of p. putida ath2-1ri/9 in the velvetleaf rhizosphere were 1000-fold higher (7 x 10(7) cfu ... | 2005 | 15883876 |
| monitoring of microbial community structure and succession in the biohydrogen production reactor by denaturing gradient gel electrophoresis (dgge). | to study the structure of microbial communities in the biological hydrogen production reactor and determine the ecological function of hydrogen producing bacteria, anaerobic sludge was obtained from the continuous stirred tank reactor (cstr) in different periods of time, and the diversity and dynamics of microbial communities were investigated by denaturing gradient gel electrophoresis (dgge). the results of dgge demonstrated that an obvious shift of microbial population happened from the beginn ... | 2005 | 15986888 |
| purification, characterization, and crystallization of the components of the nitrobenzene and 2-nitrotoluene dioxygenase enzyme systems. | the protein components of the 2-nitrotoluene (2nt) and nitrobenzene dioxygenase enzyme systems from acidovorax sp. strain js42 and comamonas sp. strain js765, respectively, were purified and characterized. these enzymes catalyze the initial step in the degradation of 2-nitrotoluene and nitrobenzene. the identical shared reductase and ferredoxin components were monomers of 35 and 11.5 kda, respectively. the reductase component contained 1.86 g-atoms iron, 2.01 g-atoms sulfur, and one molecule of ... | 2005 | 16000792 |
| degradation of simazine by microorganisms isolated from soils of spanish olive fields. | the capability of the microbial flora isolated from an olive field soil from andalusia to mineralize simazine has been analyzed. from this soil, a group of bacteria capable of degrading 60 mg simazine litre(-1) in less than a week has been isolated. these microorganisms showed a low capacity for degrading this herbicide to carbon dioxide. when total dna was isolated from this group of bacteria, we were able to detect by pcr the presence of only the atzc and the trzn genes. some components of thi ... | 2005 | 16007568 |
| microbial diversity in biofilms from corroding heating systems. | culture-independent investigations of the bacterial diversity and activity in district heating systems with and without corrosion did not make it possible to relate one group of microorganisms with the observed corrosion. fluorescence in situ hybridization by oligonucleotide probes revealed the dominance of beta-proteobacteria, sulphate reducing prokaryotes and alpha-proteobacteria. analysis of a clone library from one danish heating (dh) system showed that the most sequences formed two clusters ... | 2005 | 16019388 |
| isotopic fractionation indicates anaerobic monochlorobenzene biodegradation. | the concentration and isotopic composition of monochlorobenzene (mcb) was monitored in the plume of an anaerobic, contaminated aquifer in bitterfeld, germany. an enrichment in the carbon isotopic composition of more than 4 delta units was found at the fringes of the plume relative to the center (-26.5 %), suggesting the occurrence of in situ biodegradation of mcb. a similar enrichment was measured in a detailed cross-section of the plume and in depth-specific samples obtained in a multilevel sam ... | 2005 | 16117106 |
| degradation of chlorobenzenes by a strain of acidovorax avenae isolated from a polluted aquifer. | a subsurface microbial community was isolated from a polluted site of suquía river (córdoba-argentina), acclimated during 15 days in aerobic conditions using 1,2-dichlorobenzene (1,2-dcb) as the sole carbon source. from this acclimated community, we isolated and identified by 16s rdna analysis a strain of acidovorax avenae, which was able to perform the complete biodegradation of 1,2-dcb in two days affording stoichiometric amounts of chloride. this pure strain was also tested for biodegradation ... | 2005 | 16157172 |
| active site residues controlling substrate specificity in 2-nitrotoluene dioxygenase from acidovorax sp. strain js42. | acidovorax (formerly pseudomonas) sp. strain js42 utilizes 2-nitrotoluene as sole carbon, nitrogen, and energy source. 2-nitrotoluene 2,3-dioxygenase (2ntdo) catalyzes the initial step in 2-nitrotoluene degradation by converting 2-nitrotoluene to 3-methylcatechol. in this study, we identified specific amino acids at the active site that control specificity. the residue at position 350 was found to be critical in determining both the enantiospecificity of 2ntdo with naphthalene and the ability to ... | 2005 | 16175409 |
| a case of sepsis caused by acidovorax. | this report documents a case of sepsis caused by a recently recognized environmental organism and demonstrates the pathogenicity of this bacterium in the clinical setting. | 2005 | 16230200 |
| cloning and sequence analysis of poly(tetramethylene succinate) depolymerase from acidovorax delafieldii strain bs-3. | a gene encoding poly(tetramethylene succinate), pbs, depolymerase, pbsa, has been cloned from acidovorax delafieldii strain bs-3 chromosomal dna. the clone expressed in escherichia coli showed the ability to degrade both pbs and poly[(tetramethylene succinate)-co-adipate] that are kinds of biodegradable plastics. pbs depolymerase was considered to be a kind of lipase, since it also degrades olive oil. it had no apparent hydrophobic-amino-acid-rich region which exists in other known plastic-degra ... | 2002 | 16233195 |
| biochemical and genetic characterization of a d(-)-3-hydroxybutyrate dehydrogenase from acidovorax sp. strain sa1. | d(-)-3-hydroxybutyrate dehydrogenase (bdh; ec 1.1.1.30) from a poly(d(-)-3-hydroxybutyrate) (phb) degrading bacterium, acidovorax sp. sa1, was purified using toyopearl deae-650m, red-sepharose cl-4b, and q sepharose ff. the molecular mass of the enzyme was estimated as 27 kda by sds-page and 110 kda by gel filtration. the gene encoding bdh was cloned and sequenced, and expressed in escherichia coli. the gene product was purified in two steps with a high yield. the n-terminal amino acid sequence ... | 2004 | 16233594 |
| molecular analysis of microbial population transition associated with the start of denitrification in a wastewater treatment process. | the objective of this study is to determine the bacteria playing an important role in denitrification by monitoring the molecular dynamics accompanying the start of denitrification. | 2005 | 16238747 |
| diversity of denitrifying bacteria isolated from daejeon sewage treatment plant. | the diversity of the denitrifying bacterial populations in daejeon sewage treatment plant was examined using a culture-dependent approach. of the three hundred and seventy six bacterial colonies selected randomly from agar plates, thirty-nine strains that showed denitrifying activity were selected and subjected to further analysis. according to the morphological and biochemical properties, the thirty nine isolates were divided into seven groups. this grouping was supported by an unweighted pair ... | 2005 | 16273028 |
| transmission of nephridial bacteria of the earthworm eisenia fetida. | the lumbricid earthworms (annelid family lumbricidae) harbor gram-negative bacteria in their excretory organs, the nephridia. comparative 16s rrna gene sequencing of bacteria associated with the nephridia of several earthworm species has shown that each species of worm harbors a distinct bacterial species and that the bacteria from different species form a monophyletic cluster within the genus acidovorax, suggesting that there is a specific association resulting from radiation from a common bact ... | 2006 | 16391117 |
| heterogeneous response to biostimulation for u(vi) reduction in replicated sediment microcosms. | a field-scale experiment to assess biostimulation of uranium reduction is underway at the natural and accelerated bioremediation research field research center (frc) in oak ridge, tennessee. to simulate the field experiment, we established replicate batch microcosms containing well-mixed contaminated sediment from a well within the frc treatment zone, and we added an inoculum from a pilot-scale fluidized bed reactor representing the inoculum in the field experiment. after reduction of nitrate, b ... | 2006 | 16491308 |
| identification of a response regulator gene for catabolite control from a pcb-degrading beta-proteobacteria, acidovorax sp. kks102. | acidovorax sp. (formally pseudomonas sp.) strain kks102 carries a bph operon for the degradation of pcb/biphenyl. transcription from the pe promoter for the bph operon was found to be under catabolite control, i.e. the promoter activity was at a lower level when succinate, fumarate or acetate was added to the culture. some mutations in the immediate upstream region of the pe promoter resulted in catabolite-insensitive and constitutively low promoter activity, suggesting that a transcriptional ac ... | 2006 | 16796688 |
| stability in a denitrifying fluidized bed reactor. | this study evaluates changes in the microbial community structure and function of a pilot-scale denitrifying fluidized bed reactor during periods of constant operating conditions and periods of perturbation. the perturbations consisted of a shutdown period without feed, two disturbances in which biofilms were mechanically sheared from carrier particles, and a twofold step increase in feed nitrate concentration. in the absence of perturbations, nitrate removal was stable and consistently greater ... | 2006 | 16874554 |
| identification of acetate- or methanol-assimilating bacteria under nitrate-reducing conditions by stable-isotope probing. | stable-isotope probing (sip) was used to identify acetate- or methanol-assimilating bacteria under nitrate-reducing conditions in activated sludge. a sludge sample obtained from wastewater treatment systems was incubated in a denitrifying batch reactor fed with synthetic wastewater containing [(13)c]acetate or [(13)c]methanol as the main carbon source and nitrate as the electron acceptor. we analyzed how growth of bacterial populations was stimulated by acetate or methanol as the external carbon ... | 2006 | 16897304 |
| heterogeneous aerobic benzene-degrading communities in oxygen-depleted groundwaters. | a sandstone aquifer beneath a petrochemicals plant (siren site, uk) is heterogeneously contaminated with benzene and oxygen-depleted. despite low redox potentials in three of the most contaminated groundwaters (benzene concentrations from 17.8 to 294 mg l(-1)), we observed aerobic benzene degradation in microcosms, indicating the presence in situ of a latent community of obligate aerobic microorganisms or an active community of facultative aerobes responding rapidly to oxygen ingress. moreover, ... | 2006 | 17064267 |
| bacterial diversity in the active stage of a bioremediation system for mineral oil hydrocarbon-contaminated soils. | soils contaminated with mineral oil hydrocarbons are often cleaned in off-site bioremediation systems. in order to find out which bacteria are active during the degradation phase in such systems, the diversity of the active microflora in a degrading soil remediation system was investigated by small-subunit (ssu) rrna analysis. two sequential rna extracts from one soil sample were generated by a procedure incorporating bead beating. both extracts were analysed separately by generating individual ... | 2006 | 17074900 |
| 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 ... | 2006 | 17098542 |
| 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 ... | 2007 | 17142382 |
| protein engineering of acidovorax facilis 72w nitrilase for bioprocess development. | hydroxycarboxylic acid monomers can be used to prepare industrially important polymers. enzymatic production of such hydroxycarboxylic acids is often preferred to chemical production since the reactions are run at ambient temperature, do not require strongly acidic or basic reaction conditions, and produce the desired product with high selectivity at high conversion. however, native enzymes often do not perform desired reactions with the efficiency required for commercial applications. protein e ... | 2007 | 17154311 |
| evaluation of nitrate removal by continuous culturing of an aerobic denitrifying bacterium, paracoccus pantotrophus. | nitrate removal under aerobic conditions was investigated using pure cultures of paracoccus pantotrophus, which is a well-known aerobic-denitrifying (ad) bacterium. when a high concentration of cultures with a high carbon/nitrogen (c/n) ratio was preserved at the beginning of batch experiments, subsequently added nitrate was completely removed. when continuous culturing was perpetuated, a high nitrate removal rate (66.5%) was observed on day 4 post-culture, although gradual decreases in ad abili ... | 2006 | 17163031 |
| identification of bacterial n-acylhomoserine lactones (ahls) with a combination of ultra-performance liquid chromatography (uplc), ultra-high-resolution mass spectrometry, and in-situ biosensors. | n-acylated homoserine lactones (ahls) are produced by gram-negative bacteria as communication signals and are frequently studied as mediators of the "quorum sensing" response of bacterial communities. several reports have recently been published on the identification of ahls from different species and attempts have been made to study their role in natural habitats, for example the surface of plant roots in the rhizosphere. in this article, different analytical methods, including bacterial biosen ... | 2007 | 17165024 |
| desulfurization of aromatic sulfonates by rhizosphere bacteria: high diversity of the asfa gene. | the plant growth-promoting effect of pseudomonas putida s-313 is associated with its ability to desulfurize arylsulfonates. to understand this further, other plant-associated bacteria able to desulfurize a range of arylsulfonates were isolated from the rhizospheres of winter and spring barley. the isolates belonged to the beta-proteobacteria, including bacteria from the variovorax paradoxus group and from the acidovorax genus. they desulfurized toluenesulfonate to p-cresol, and were found to con ... | 2007 | 17222151 |
| biodegradation of chlorobenzene under hypoxic and mixed hypoxic-denitrifying conditions. | pseudomonas veronii strain ufz b549, acidovorax facilis strain ufz b530, and a community of indigenous groundwater bacteria, adapted to oxygen limitation, were cultivated on chlorobenzene and its metabolites 2-chloro-cis,cis-muconate and acetate/succinate under hypoxic and denitrifying conditions. highly sensitive approaches were used to maintain defined low oxygen partial pressures in an oxygen-re-supplying headspace. with low amounts of oxygen available all cultures converted chlorobenzene, th ... | 2007 | 17279449 |
| metabolic activity and phylogenetic diversity of reed (phragmites australis) periphyton bacterial communities in a hungarian shallow soda lake. | in 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 ... | 2007 | 17406774 |
| crystallization and preliminary x-ray analysis of the electron-transfer complex of rieske-type [2fe-2s] ferredoxin and nadh-dependent ferredoxin reductase derived from acidovorax sp. strain kks102. | the electron-transfer complex of bpha3, a rieske-type [2fe-2s] ferredoxin, and bpha4, a nadh-dependent ferredoxin reductase, was crystallized using the sitting-drop vapour-diffusion method under anaerobic conditions. the obtained crystals were analyzed by sds-page, which showed that they contained both bpha3 and bpha4. the crystals belong to space group p2(1), with unit-cell parameters a = 60.60, b = 173.72, c = 60.98 a, beta = 115.8 degrees, and diffracted to a resolution of 1.9 a. | 2007 | 17554177 |
| isolation and antifungal activity of lignans from myristica fragrans against various plant pathogenic fungi. | in a search for plant extracts with potent in vivo antifungal activity against various plant diseases, we found that treatment with a methanol extract of myristica fragrans houttyn (nutmeg) seeds reduced the development of various plant diseases. the objectives of the present study were to isolate and determine antifungal substances from my. fragrans and to evaluate their antifungal activities. | 2007 | 17659535 |
| protein engineering of nitrilase for chemoenzymatic production of glycolic acid. | a key step in a chemoenzymatic process for the production of high-purity glycolic acid (gla) is the enzymatic conversion of glycolonitrile (gln) to ammonium glycolate using a nitrilase derived from acidovorax facilis 72w. protein engineering and over-expression of this nitrilase, combined with optimized fermentation of an e. coli transformant were used to increase the enzyme-specific activity up to 15-fold and the biocatalyst-specific activity up to 125-fold. these improvements enabled achieveme ... | 2008 | 17787011 |
| diversity analysis of antagonists from rice-associated bacteria and their application in biocontrol of rice diseases. | to understand the diversity, taxonomy and antagonistic potential of rice-associated bacteria, and to discover new bacteria for biocontrol of rice foliar pathogens. | 2008 | 17850318 |
| molecular mechanism of the redox-dependent interaction between nadh-dependent ferredoxin reductase and rieske-type [2fe-2s] ferredoxin. | the electron transfer system of the biphenyl dioxygenase bpha, which is derived from acidovorax sp. (formally pseudomonas sp.) strain kks102, is composed of an fad-containing nadh-ferredoxin reductase (bpha4) and a rieske-type [2fe-2s] ferredoxin (bpha3). biochemical studies have suggested that the whole electron transfer process from nadh to bpha3 comprises three consecutive elementary electron-transfer reactions, in which bpha3 and bpha4 interact transiently in a redox-dependent manner. initia ... | 2007 | 17850818 |