Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| phcs represses gratuitous expression of phenol-metabolizing enzymes in comamonas testosteroni r5. | we identified an open reading frame, designated phcs, downstream of the transcriptional activator gene (phcr) for the expression of multicomponent phenol hydroxylase (mph) in comamonas testosteroni r5. the deduced product of phcs was homologous to aphs of c. testosteroni ta441, which belongs to the gntr family of transcriptional regulators. the transformation of pseudomonas aeruginosa pao1c (phenol negative, catechol positive) with pror502 containing phcr and the mph genes conferred the ability ... | 2001 | 11418563 |
| pseudomonas pickettii (biovar va-ii): a rare cause of bacteremias in haematologic patients. | 2001 | 11422418 | |
| organization and regulation of meta cleavage pathway genes for toluene and o-xylene derivative degradation in pseudomonas stutzeri ox1. | pseudomonas stutzeri ox1 meta pathway genes for toluene and o-xylene catabolism were analyzed, and loci encoding phenol hydroxylase, catechol 2,3-dioxygenase, 2-hydroxymuconate semialdehyde dehydrogenase, and 2-hydroxymuconate semialdehyde hydrolase were mapped. phenol hydroxylase converted a broad range of substrates, as it was also able to transform the nongrowth substrates 2,4-dimethylphenol and 2,5-dimethylphenol into 3,5-dimethylcatechol and 3,6-dimethylcatechol, respectively, which, howeve ... | 2001 | 11425758 |
| evaluation of vitek 2 rapid identification and susceptibility testing system against gram-negative clinical isolates. | a total of 281 strains of miscellaneous members of the family enterobacteriaceae, pseudomonas aeruginosa, and other gram-negative bacteria were evaluated by use of identification tests with the vitek 2 system (biomérieux) and an api identification system (biomérieux). a total of 237 (95%) strains were correctly identified to the species level. only six (2.1%) strains were misidentified, and eight (2.8%) strains were not identified. among 14 strains with discrepant identifications, 8 (57.1%) stra ... | 2001 | 11474023 |
| isolation of an insertion sequence from ralstonia solanacearum race 1 and its potential use for strain characterization and detection. | a new insertion sequence (is), is1405, was isolated and characterized from a ralstonia solanacearum race 1 strain by the method of insertional inactivation of the sacb gene. sequence analysis indicated that the is is closely related to the members of is5 family, but the extent of nucleotide sequence identity in 5' and 3' noncoding regions between is1405 and other members of is5 family is only 23 to 31%. nucleotide sequences of these regions were used to design specific oligonucleotide primers fo ... | 2001 | 11525989 |
| identification of strains of alcaligenes and agrobacterium by a polyphasic approach. | the number of stable discriminant biochemical characters is limited in the genera alcaligenes and agrobacterium, whose species are consequently difficult to distinguish from one another by conventional tests. moreover, genomic studies have recently drastically modified the nomenclature of these genera; for example, alcaligenes xylosoxidans was transferred to the genus achromobacter in 1998. twenty-five strains of achromobacter xylosoxidans, three strains of an agrobacterium sp., five strains of ... | 2001 | 11526136 |
| infection of acanthamoeba polyphaga with simkania negevensis and s. negevensis survival within amoebal cysts. | simkania negevensis, a novel microorganism belonging to the family simkaniaceae in the order chlamydiales, has an intracellular developmental cycle during which two morphological entities, elementary bodies (eb) and reticulate bodies (rb), are seen by electron microscopy. rates of seropositivity to the organism are high in certain population groups, and s. negevensis has been associated with respiratory illness in humans. this study reports for the first time the ability of s. negevensis to surv ... | 2001 | 11571186 |
| genetic and functional analysis of the tbc operons for catabolism of alkyl- and chloroaromatic compounds in burkholderia sp. strain js150. | burkholderia sp. strain js150 is able to metabolize a wide range of alkyl-and chloroaromatic hydrocarbons through multiple, apparently redundant catabolic pathways. previous research has shown that strain js150 is able to synthesize enzymes for multiple upper pathways as well as multiple lower pathways to accommodate variously substituted catechols that result from degradation of complex mixtures of monoaromatic compounds. we report here the genetic organization and functional characterization o ... | 2001 | 11571188 |
| taxonomy and identification of the burkholderia cepacia complex. | 2001 | 11574551 | |
| influence of substrate exposure history on biodegradation in a porous medium. | this study investigates the influence of fluctuating toluene concentrations on aerobic toluene degradation in a sandy porous medium colonized with ralstonia pickettii pko1. column effluent toluene concentrations were found to increase after a temporary decrease in influent toluene concentration. subsequent examination of the spatial gradient of toluene degradative activity in the column suggested that the observed increase in effluent toluene concentrations was attributable to an adverse effect ... | 2001 | 11588828 |
| bacteria and archaea physically associated with gulf of mexico gas hydrates. | although there is significant interest in the potential interactions of microbes with gas hydrate, no direct physical association between them has been demonstrated. we examined several intact samples of naturally occurring gas hydrate from the gulf of mexico for evidence of microbes. all samples were collected from anaerobic hemipelagic mud within the gas hydrate stability zone, at water depths in the ca. 540- to 2,000-m range. the delta(13)c of hydrate-bound methane varied from -45.1 per thous ... | 2001 | 11679338 |
| [ralstonia pickettii pneumonia in an inmunocompetent adult]. | 2001 | 11707228 | |
| characterization of oxa-29 from legionella (fluoribacter) gormanii: molecular class d beta-lactamase with unusual properties. | a class d beta-lactamase determinant was isolated from the genome of legionella (fluoribacter) gormanii atcc 33297(t). the enzyme, named oxa-29, is quite divergent from other class d beta-lactamases, being more similar (33 to 43% amino acid identity) to those of groups iii (oxa-1) and iv (oxa-9, oxa-12, oxa-18, and oxa-22) than to other class d enzymes (21 to 24% sequence identity). phylogenetic analysis confirmed the closer ancestry of oxa-29 with members of the former groups. the oxa-29 enzyme ... | 2001 | 11709332 |
| pcr-based detection and identification of burkholderia cepacia complex pathogens in sputum from cystic fibrosis patients. | pcr amplification of the reca gene followed by restriction fragment length polymorphism (rflp) analysis was investigated for the rapid detection and identification of burkholderia cepacia complex genomovars directly from sputum. successful amplification of the b. cepacia complex reca gene from cystic fibrosis (cf) patient sputum samples containing b. cepacia genomovar i, burkholderia multivorans, b. cepacia genomovar iii, burkholderia stabilis, and burkholderia vietnamiensis was demonstrated. in ... | 2001 | 11724828 |
| identification of pandoraea species by 16s ribosomal dna-based pcr assays. | the recently described genus pandoraea contains five named species (pandoraea apista, pandoraea pulmonicola, pandoraea pnomenusa, pandoraea sputorum, and pandoraea norimbergensis) and four unnamed genomospecies. pandoraea spp. have mainly been recovered from the respiratory tracts of cystic fibrosis (cf) patients. accurate genus- and species-level identification by routine clinical microbiology methods is difficult, and differentiation from burkholderia cepacia complex organisms may be especiall ... | 2001 | 11724860 |
| culture with bactec peds plus/f bottle compared with conventional methods for detection of bacteria in synovial fluid. | an evaluation was undertaken to determine the utility of the bactec peds plus/f bottle and the bactec 9240 instrument (becton dickinson diagnostic instrument systems, sparks, md.) for the detection of clinically significant microorganisms in synovial fluid specimens. the peds plus/f bottle was used because in our laboratory the quantity of synovial fluid available for culture is frequently in the range of 0.5 to 3.0 ml. the culture results obtained with the peds plus/f bottle were compared to th ... | 2001 | 11724863 |
| case of catheter sepsis with ralstonia gilardii in a child with acute lymphoblastic leukemia. | acute lymphoblastic leukemia was diagnosed in a 7-year-old girl. two months after insertion of a central venous catheter, she developed fever and complained of headache and abdominal pain. physical examination revealed no focus of infection. a gram-negative nonfermenting bacillus was recurrently cultured from blood. extensive biochemical testing and 16s ribosomal dna sequencing led to the identification of ralstonia gilardii. | 2001 | 11724891 |
| one case each of recurrent meningitis and hemoperitoneum infection with ralstonia mannitolilytica. | two clinical cases of infection with ralstonia mannitolilytica are described: a recurrent meningitis on an implanted intraventricular catheter and an infected hemoperitoneum as a complication of a cholangiocarcinoma. the strains were first misidentified as pseudomonas fluorescens and burkholderia cepacia. further testing lead to the identification as ralstonia pickettii biovar 3/"thomasii," which was recently shown to represent a separate species, r. mannitolilytica (list editor n. weiss, int. j ... | 2001 | 11724893 |
| directed evolution of toluene ortho-monooxygenase for enhanced 1-naphthol synthesis and chlorinated ethene degradation. | trichloroethylene (tce) is the most frequently detected groundwater contaminant, and 1-naphthol is an important chemical manufacturing intermediate. directed evolution was used to increase the activity of toluene ortho-monooxygenase (tom) of burkholderia cepacia g4 for both chlorinated ethenes and naphthalene oxidation. when expressed in escherichia coli, the variant tom-green degraded tce (2.5 +/- 0.3 versus 1.39 +/- 0.05 nmol/min/mg of protein), 1,1-dichloroethylene, and trans-dichloroethylene ... | 2002 | 11751810 |
| endotoxin levels in steam and reservoirs of table-top steam sterilizers. | to document endotoxin levels in "statim" cassette sterilizer reservoirs and in steam delivered to the cassette in the unwrapped instrument cycle. to document endotoxin levels in sterilizer reservoir water using different management protocols. | 2002 | 11828908 |
| ralstonia pickettii bacteraemia in a cord blood transplant recipient. | a seven-year old boy with acute lymphoblastic leukemia underwent an hla mismatched cord blood transplant. he developed grade 2 mucositis requiring morphine infusion and grade 3-4 hyperacute graft-versus-host disease affecting the skin, gastrointestinal tract, and liver requiring pulse methylprednisolone. on days 21, 23, and 24 post-transplant, blood culture obtained through the central line and periphery were positive for ralstonia pickettii. the same strain (with the same biochemical profile an ... | 2002 | 11841049 |
| detection and activity of insertion sequences in environmental strains of burkholderia. | the presence of two insertion sequences, is406 and is407, was tested by polymerase chain reaction (pcr) amplification in 25 strains representing 15 burkholderia species and the close relative ralstonia pickettii. a total of 50% of the 25 strains contained at least one of the two insertion sequences (iss) and a statistically significant correlation was found between the occurrences of is406 and is407. moreover, pcr-rflp studies of the amplified fragments showed that is406 is largely conserved amo ... | 2001 | 11846770 |
| in vitro activities of bal9141, a novel broad-spectrum pyrrolidinone cephalosporin, against gram-negative nonfermenters. | the activities of bal9141 (formerly ro 63-9141), a novel pyrrolidinone-3-ylidenemethyl cephalosporin, against 244 strains of gram-negative nonfermenters were evaluated. the overall mic at which 50% of isolates are inhibited (mic50) and the overall mic90 were 2 and 64 microg/ml, respectively, which are similar to those of imipenem, lower than those of the other cephalosporins tested, amoxicillin, and the ticarcillin-clavulanic acid combination, and much higher than those of ciprofloxacin. bal9141 ... | 2002 | 11850276 |
| effects of t4 lysozyme release from transgenic potato roots on bacterial rhizosphere communities are negligible relative to natural factors. | rhizosphere bacterial communities of two transgenic potato lines which produce t4 lysozyme for protection against bacterial infections were analyzed in comparison to communities of wild-type plants and transgenic controls not harboring the lysozyme gene. rhizosphere samples were taken from young, flowering, and senescent plants at two field sites in three consecutive years. the communities were characterized in a polyphasic approach. cultivation-dependent methods included heterotrophic plate cou ... | 2002 | 11872484 |
| biochemical and susceptibility tests useful for identification of nonfermenting gram-negative rods. | six hundred nineteen strains of nonfermenting gram-negative rods were tested for alkaline phosphatase, benzyl-arginine arylamidase, pyrrolidonyl arylamidase, ethylene glycol acidification, and susceptibility to desferrioxamine and colistin. the results were highly discriminant. therefore, the proposed tests may be helpful for the identification of this group of organisms. | 2002 | 11880447 |
| epidemiology of burkholderia cepacia complex in patients with cystic fibrosis, canada. | the burkholderia cepacia complex is an important group of pathogens in patients with cystic fibrosis (cf). although evidence for patient-to-patient spread is clear, microbial factors facilitating transmission are poorly understood. to identify microbial clones with enhanced transmissibility, we evaluated b. cepacia complex isolates from patients with cf from throughout canada. a total of 905 isolates from the b. cepacia complex were recovered from 447 patients in 8 of the 10 provinces; 369 (83%) ... | 2002 | 11897071 |
| analysis of bacteria contaminating ultrapure water in industrial systems. | bacterial populations inhabiting ultrapure water (upw) systems were investigated. the analyzed upw systems included pilot scale, bench scale, and full size upw plants employed in the semiconductor and other industries. bacteria present in the polishing loop of the upw systems were enumerated by both plate counts and epifluorescence microscopy. assessment of bacterial presence in upw by epifluorescence microscopy (cyanotolyl tetrazolium chloride [ctc] and dapi [4',6'-diamidino-2-phenylindole] sta ... | 2002 | 11916667 |
| development and characterization of a green fluorescent protein-based bacterial biosensor for bioavailable toluene and related compounds. | a green fluorescent protein-based pseudomonas fluorescens strain a506 biosensor was constructed and characterized for its potential to measure benzene, toluene, ethylbenzene, and related compounds in aqueous solutions. the biosensor is based on a plasmid carrying the toluene-benzene utilization (tbu) pathway transcriptional activator tbut from ralstonia pickettii pko1 and a transcriptional fusion of its promoter ptbua1 with a promoterless gfp gene on a broad-host-range promoter probe vector. tbu ... | 2002 | 11916719 |
| comparative evaluation of the bd phoenix and vitek 2 automated instruments for identification of isolates of the burkholderia cepacia complex. | we evaluated two new automated identification systems, the bd phoenix (becton dickinson) and the vitek 2 (biomérieux), for identification of isolates of the burkholderia cepacia complex (bcc). the test sample included 42 isolates of the highly virulent and epidemic genomovar iii, 45 isolates of b. multivorans, and 47 isolates of other members of the bcc. rates of correct identification by the bd phoenix and vitek 2 were similar when all bcc isolates were considered (50 and 53%, respectively) but ... | 2002 | 11980954 |
| characterization of unusual bacteria isolated from respiratory secretions of cystic fibrosis patients and description of inquilinus limosus gen. nov., sp. nov. | using a polyphasic approach (including cellular protein and fatty acid analysis, biochemical characterization, 16s ribosomal dna sequencing, and dna-dna hybridizations), we characterized 51 bacterial isolates recovered from respiratory secretions of cystic fibrosis (cf) patients. our analyses showed that 24 isolates belong to taxa that have so far not (or only rarely) been reported from cf patients. these taxa include acinetobacter sp., bordetella hinzii, burkholderia fungorum, comamonas testost ... | 2002 | 12037065 |
| genetic and biochemical characterization of a 2,4,6-trichlorophenol degradation pathway in ralstonia eutropha jmp134. | ralstonia eutropha jmp134 can grow on several chlorinated aromatic pollutants, including 2,4-dichlorophenoxyacetate and 2,4,6-trichlorophenol (2,4,6-tcp). although a 2,4,6-tcp degradation pathway in jmp134 has been proposed, the enzymes and genes responsible for 2,4,6-tcp degradation have not been characterized. in this study, we found that 2,4,6-tcp degradation by jmp134 was inducible by 2,4,6-tcp and subject to catabolic repression by glutamate. we detected 2,4,6-tcp-degrading activities in jm ... | 2002 | 12057943 |
| ralstonia pickettii traced in blood culture bottles. | over a 9-month period, 14 strains of ralstonia pickettii were isolated from various biological samples inoculated in a blood culture medium. molecular epidemiological investigation confirmed the relatedness of the strains. the source of the contamination proved to be the blood culture bottle caps. | 2002 | 12089303 |
| infection by ralstonia species in cystic fibrosis patients: identification of r. pickettii and r. mannitolilytica by polymerase chain reaction. | the frequency of respiratory tract infections caused by ralstonia species in persons with cystic fibrosis (cf) and the role of these species in cf pulmonary disease are not well documented. in part, this lack of documentation may be attributed to the difficulty in accurately identifying ralstonia species; r. mannitolilytica and r. pickettii in particular may be misidentified as other closely related species, particularly those of the burkholderia cepacia complex. we used polyphasic analyses to i ... | 2002 | 12095436 |
| origins of the 2,4-dinitrotoluene pathway. | the degradation of synthetic compounds requires bacteria to recruit and adapt enzymes from pathways for naturally occurring compounds. previous work defined the steps in 2,4-dinitrotoluene (2,4-dnt) metabolism through the ring fission reaction. the results presented here characterize subsequent steps in the pathway that yield the central metabolic intermediates pyruvate and propionyl coenzyme a (coa). the genes encoding the degradative pathway were identified within a 27-kb region of dna cloned ... | 2002 | 12107140 |
| microbial degradation of quinoline by immobilized cells of burkholderia pickettii. | a quinoline-biodegrading microorganism was isolated from activated sludge of coke-oven wastewater treatment plant using quinoline as sole carbon and nitrogen source. it is a gram negative, rod-shaped and aerobic strain, which was identified as burkholderia pickettii. the biodegradation of quinoline was carried out with this isolated strain. analysis by high performance liquid chromatography and gas chromatography/mass spectrum (gc/ms) revealed that 2-hydroxyquinoline (2-oh-q) was the first inter ... | 2002 | 12108721 |
| method for qualifying microbial removal performance of 0.1 micron rated filters. part iv: retention of hydrogenophaga pseudoflava (atcc 700892) and ralstonia pickettii (atcc 700591) by 0.2 and 0.22 micron rated filters. | ralstonia pickettii has emerged as a bioburden microorganism of considerable importance in pharmaceutical processes utilizing conventional 0.2 or 0.22 micron rated "sterilizing grade" filters. in this article, we re-evaluated and studied the retention efficiencies of 0.2 micron rated nylon 6.6 and 0.22 microns rated modified polyvinylidene fluoride (pvdf) filters for hydrogenophaga pseudoflava (atcc 700892) and r. pickettii (atcc 700591). out of a total of forty-four 0.2/0.22 micron rated filter ... | 2002 | 12109335 |
| culture-based and non-growth-dependent detection of the burkholderia cepacia complex in soil environments. | burkholderia cepacia complex (bcc) bacteria reside in soil, plant rhizospheres, and water, but their prevalence and distribution in outdoor environments is not clear. we sampled a variety of soil and rhizosphere environments with which people may have contact: playgrounds, athletic fields, parks, hiking trails, residential yards, and gardens. a total of 91 sites was sampled in three large u.s. cities. in the first phase of the study, putative bcc isolates were recovered on burkholderia cepacia s ... | 2002 | 12147469 |
| [cloning, sequencing and high expression in escherichia coli of d-hydantoinase gene from burkholderia pickettii]. | a strain, mmr003, used for d-p-hpg production in industry was classified as burkholderia pickettii by morphological observation and biochemical characterization. the gene encoding the d-hydantoinase enzyme was cloned, sequenced and expressed in escherichia coli. the nucleotide sequence of the 5.0 kb insert of subclone pxz-total was determined. one open reading frame of 1374 bp was found and predicted to encode a polypeptide consisting of 458 amino acids in size of 50 kd. the amino acid sequence ... | 2002 | 12148274 |
| survival and nutritional requirements of three bacteria isolated from ultrapure water. | bacteria isolated previously from ultrapure water (upw) systems were examined for their ability to survive in upw, with the ultimate goal of elucidating potential carbon and energy sources for the bacteria. two strains of ralstonia pickettii isolated from different areas within the upw system (pretreatment and polishing loop, and referred to as strains 3a1 and mf254a, respectively) and a strain of bradyrhizobium sp. were compared to increase our understanding of the fundamental behavior of bacte ... | 2002 | 12161774 |
| direct pcr detection of burkholderia cepacia complex and identification of its genomovars by using sputum as source of dna. | we developed a nested pcr assay that detects the reca gene of the burkholderia cepacia complex in sputum. the product of the first pcr round is also used to identify the genomovar of the pathogen. the protocol achieves high sensitivity and specificity with simple interpretation of genomovar status. | 2002 | 12202599 |
| 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 |
| a new modified ortho cleavage pathway of 3-chlorocatechol degradation by rhodococcus opacus 1cp: genetic and biochemical evidence. | the 4-chloro- and 2,4-dichlorophenol-degrading strain rhodococcus opacus 1cp has previously been shown to acquire, during prolonged adaptation, the ability to mineralize 2-chlorophenol. in addition, homogeneous chlorocatechol 1,2-dioxygenase from 2-chlorophenol-grown biomass has shown relatively high activity towards 3-chlorocatechol. based on sequences of the n terminus and tryptic peptides of this enzyme, degenerate pcr primers were now designed and used for cloning of the respective gene from ... | 2002 | 12218013 |
| microbial origin of glutamate, hibernation and tissue trauma: an in vivo microdialysis study. | using quantitative microdialysis in hibernating arctic ground squirrels (ags), striatal glutamate concentrations ([glu](dia)) progressively increased to approximately 200 microm after 3 days of microdialysis in euthermic but not hibernating ground squirrels. initially, the progressive increase in [glu](dia) was thought to be related to greater tissue response in euthermic animals. alternatively, given the vastly different body temperatures between the two groups (37 vs. 3 degrees c), glutamate m ... | 2002 | 12323415 |
| carbon and hydrogen stable isotope fractionation during aerobic bacterial degradation of aromatic hydrocarbons. | 13c/(12)c and d/h stable isotope fractionation during aerobic degradation was determined for pseudomonas putida strain mt-2, pseudomonas putida strain f1, ralstonia pickettii strain pko1, and pseudomonas putida strain ncib 9816 grown with toluene, xylenes, and naphthalene. different types of initial reactions used by the respective bacterial strains could be linked with certain extents of stable isotope fractionation during substrate degradation. | 2002 | 12324375 |
| ability of the microscan rapid gram-negative id type 3 panel to identify nonenteric glucose-fermenting and nonfermenting gram-negative bacilli. | the microscan rapid neg id3 panel is designed for the identification of enterobacteriaceae and nonenteric glucose-fermenting and nonfermenting gram-negative bacilli. we evaluated this panel for its ability to identify gram-negative non-enterobacteriaceae bacteria. a total of 134 strains, representing 26 genera and 42 species, were taken from storage at -70(o)c, passaged three times before testing, and inoculated into the panels according to the manufacturer's directions before being inserted int ... | 2002 | 12354875 |
| use of 16s rrna gene sequencing for identification of nonfermenting gram-negative bacilli recovered from patients attending a single cystic fibrosis center. | during 1999, we used partial 16s rrna gene sequencing for the prospective identification of atypical nonfermenting gram-negative bacilli isolated from patients attending our cystic fibrosis center. of 1,093 isolates of nonfermenting gram-negative bacilli recovered from 148 patients, 46 (4.2%) gave problematic results with conventional phenotypic tests. these 46 isolates were genotypically identified as pseudomonas aeruginosa (19 isolates, 12 patients), achromobacter xylosoxidans (10 isolates, 8 ... | 2002 | 12354883 |
| cloning of the class d beta-lactamase gene from burkholderia pseudomallei and studies on its expression in ceftazidime-susceptible and -resistant strains. | ceftazidime is the antibiotic of choice for the treatment of melioidosis. ceftazidime-resistant burkholderia pseudomallei have been identified and beta-lactamase production implicated in resistance. in this study, 25 strains of b. pseudomallei (15 clinical and 10 environmental strains) were examined for their ability to yield mutants that overexpress beta-lactamase. ceftazidime-resistant mutants were selected readily at high frequency and displayed four- to eight-fold increases in the mics of ce ... | 2002 | 12356787 |
| characterization of the adaptive response to trichloroethylene-mediated stresses in ralstonia pickettii pko1. | in ralstonia pickettii pko1, a denitrifying toluene oxidizer that carries a toluene-3-monooxygenase (t3mo) pathway, the biodegradation of toluene and trichloroethylene (tce) by the organism is induced by tce at high concentrations. in this study, the effect of tce preexposure was studied in the context of bacterial protective response to tce-mediated toxicity in this organism. the results of tce degradation experiments showed that cells induced by tce at 110 mg/liter were more tolerant to tce-me ... | 2002 | 12406709 |
| change of surface structure of poly(3-hydroxybutyrate) film upon enzymatic hydrolysis by phb depolymerase. | the change in the surface structure of poly[(r)-3-hydroxybutyrate] [phb] films upon the enzymatic hydrolysis was analyzed by attenuated total reflection infrared [atr/ir] spectrometry. as enzymes, phb depolymerases isolated from ralstonia pickettii t1 and pseudomonas stutzeri were used. by curve decomposition of the carbonyl stretching band of atr/ir spectra, the change in the surface crystallinity of phb films by exposure to buffer containing 0, 1, and 4 microg of phb depolymerases was estimate ... | 2002 | 12425671 |
| cross-regulation between a novel two-component signal transduction system for catabolism of toluene in pseudomonas mendocina and the todst system from pseudomonas putida. | the tmoabcdef genes encode the toluene-4-monooxygenase from pseudomonas mendocina kr1. upstream from the tmoa gene an open reading frame, tmox, encoding a protein 83% identical to todx (todx being the initial gene in the todxfc1c2badegih operon from pseudomonas putida dot-t1e) was found. the tmox gene is also the initial gene in the tmoxabcdef gene cluster. the transcription initiation point from the tmox promoter was mapped, and the sequence upstream revealed striking identity with the promoter ... | 2002 | 12446657 |
| bacterial chemotaxis toward environmental pollutants: role in bioremediation. | 2002 | 12450797 | |
| metal ion dependence of recombinant escherichia coli allantoinase. | allantoinase is a suspected dinuclear metalloenzyme that catalyzes the hydrolytic cleavage of the five-member ring of allantoin (5-ureidohydantoin) to form allantoic acid. recombinant escherichia coli allantoinase purified from overproducing cultures amended with 2.5 mm zinc, 1 mm cobalt, or 1 mm nickel ions was found to possess approximately 1.4 zn, 0.0 co, 0.0 ni, and 0.4 fe; 0.1 zn, 1.0 co, 0.0 ni, and 0.2 fe; and 0.0 zn, 0.0 co, 0.6 ni, and 0.1 fe per subunit, respectively, whereas protein o ... | 2003 | 12486048 |
| survival and growth of francisella tularensis in acanthamoeba castellanii. | francisella tularensis is a highly infectious, facultative intracellular bacterium which causes epidemics of tularemia in both humans and mammals at regular intervals. the natural reservoir of the bacterium is largely unknown, although it has been speculated that protozoa may harbor it. to test this hypothesis, acanthamoeba castellanii was cocultured with a strain of f. tularensis engineered to produce green fluorescent protein (gfp) in a nutrient-rich medium. gfp fluorescence within a. castella ... | 2003 | 12514047 |
| cloning, sequencing, and overexpression in escherichia coli of a phenylserine dehydratase gene from ralstonia pickettii ps22. | the structural gene coding for phenylserine dehydratase from ralstonia pickettii ps22 was cloned into escherichia coli cells, and the nucleotide sequence was identified. the predicted amino acid sequence had high sequence similarity to biodegradative and biosynthetic threonine dehydratases from e. coli and serine dehydratase from human liver. transformed e. coli cells overproduced phenylserine dehydratase, and the recombinant enzyme was purified to homogeneity with a high yield and characterized ... | 2002 | 12596884 |
| diversity of tetracycline resistance genes in bacteria from chilean salmon farms. | twenty-five distinct tetracycline-resistant gram-negative bacteria recovered from four chilean fish farms with no history of recent antibiotic use were examined for the presence of tetracycline resistance (tet) genes. sixty percent of the isolates carried 1 of the 22 known tet genes examined. the distribution was as follows. the tet(a) gene was found in six isolates. the tet(b) gene was found in two isolates, including the first description in the genus brevundimonas: two isolates carried the te ... | 2003 | 12604516 |
| n2o-producing microorganisms in the gut of the earthworm aporrectodea caliginosa are indicative of ingested soil bacteria. | the main objectives of this study were (i) to determine if gut wall-associated microorganisms are responsible for the capacity of earthworms to emit nitrous oxide (n(2)o) and (ii) to characterize the n(2)o-producing bacteria of the earthworm gut. the production of n(2)o in the gut of garden soil earthworms (aporrectodea caliginosa) was mostly associated with the gut contents rather than the gut wall. under anoxic conditions, nitrite and n(2)o were transient products when supplemental nitrate was ... | 2003 | 12620856 |
| an improved enrichment broth for isolation of escherichia coli o157, with specific reference to starved cells, from radish sprouts. | an enrichment broth was developed for the efficient isolation of escherichia coli o157 from radish sprouts. the broth was buffered peptone water containing 0.5% sodium thioglycolate (stg-bpw), which was designed to allow growth of e. coli o157 in starved and unstarved states. however, this medium suppressed the growth of non-carbohydrate-fermenting obligate aerobes whose colonial appearance on sorbitol macconkey agar containing cefixime and tellurite (ct-smac) resembled that of e. coli o157. bot ... | 2003 | 12620883 |
| characterization of a small plasmid (pmbcp) from bovine pseudomonas pickettii that confers cadmium resistance. | this is the first report of isolation of pseudomonas pickettii from a normal adult bovine duodenum. this organism was one of several bacteria isolated as part of a study to examine cadmium resistance genes (cad(r)) for use in generating transgenic plants to reclaim cadmium-contaminated soils in kansas. p. pickettii containing a plasmid of 2.2kb (designated pmbcp) grew in luria-bertani broth and agar containing up to 800 microm of cadmium chloride and was resistant to 16 antibiotics. curing the o ... | 2003 | 12651180 |
| simple sequence repeats and compositional bias in the bipartite ralstonia solanacearum gmi1000 genome. | ralstonia solanacearum is an important plant pathogen. the genome of r. solananearum gmi1000 is organised into two replicons (a 3.7-mb chromosome and a 2.1-mb megaplasmid) and this bipartite genome structure is characteristic for most r. solanacearum strains. to determine whether the megaplasmid was acquired via recent horizontal gene transfer or is part of an ancestral single chromosome, we compared the abundance, distribution and composition of simple sequence repeats (ssrs) between both repli ... | 2003 | 12697060 |
| removal of phenanthrene from soil by co-cultures of bacteria and fungi pregrown on sugarcane bagasse pith. | sixteen co-cultures composed of four bacteria and four fungi grown on sugarcane bagasse pith were tested for phenanthrene degradation in soil. the four bacteria were identified as pseudomonas aeruginose, ralstonia pickettii, pseudomonas sp. and pseudomonas cepacea. the four fungi were identified as: penicillium sp., trichoderma viride, alternaria tenuis and aspergillus terrus that were previously isolated from different hydrocarbon-contaminated soils. fungi had a statistically significant positi ... | 2003 | 12699938 |
| energy-generating enzymes of burkholderia cepacia and their interactions with macrophages. | we previously demonstrated that several clinical and environmental isolates of burkholderia cepacia secreted atp-utilizing enzymes to the medium; the secretion of these enzymes by cystic fibrosis lung isolate strain 38 was shown to be greatly enhanced in the presence of alpha(2)-macroglobulin. fractionation of the growth medium of cystic fibrosis isolate strain 71 belonging to genomovar i demonstrated the presence of two additional proteins, homologues of pseudomonas aeruginosa azurin and cytoch ... | 2003 | 12730177 |
| microbial population diversity in the urethras of healthy males and males suffering from nonchlamydial, nongonococcal urethritis. | nonchlamydial, nongonococcal urethritis (ncngu) is suggested to be a sexually transmitted disease in men. ncngu patients were compared to control subjects with regard to the presence of potentially infectious bacteria in the first void urine. patients' pre- and post-antibiotic-treatment urine samples and two samples obtained 2 weeks apart from healthy volunteers, who did not receive antibiotic therapy, were analyzed with broad-spectrum pcr tests aiming at eubacterial small subunit rrna genes. re ... | 2003 | 12734237 |
| evaluation of the vitek 2 id-gnb assay for identification of members of the family enterobacteriaceae and other nonenteric gram-negative bacilli and comparison with the vitek gni+ card. | we evaluated the vitek 2 id-gnb identification card (biomérieux, inc., durham, n.c.) for its ability to identify members of the family enterobacteriaceae and other gram-negative bacilli that are isolated in clinical microbiology laboratories. using 482 enteric stock cultures and 103 strains of oxidase-positive, gram-negative glucose-fermenting and nonfermenting bacilli that were maintained at -70 degrees c and passaged three times before use, we inoculated cards according to the manufacturer's d ... | 2003 | 12734254 |
| sepsis, multiple organ failure, and death due to pandoraea pnomenusa infection after lung transplantation. | a 30-year-old man died with pandoraea pnomenusa sepsis after lung transplantation. pandoraea species are gram-negative rods, closely related to, and commonly misidentified as, burkholderia cepacia complex or ralstonia species. heretofore considered soil bacteria and colonizers that infect patients with chronic lung diseases, pandoraea species can produce severe infections. | 2003 | 12734295 |
| purification and properties of an intracellular 3-hydroxybutyrate-oligomer hydrolase (phaz2) in ralstonia eutropha h16 and its identification as a novel intracellular poly(3-hydroxybutyrate) depolymerase. | an intracellular 3-hydroxybutyrate (3hb)-oligomer hydrolase (phaz2(reu)) of ralstonia eutropha was purified from escherichia coli harboring a plasmid containing phaz2(reu). the purified enzyme hydrolyzed linear and cyclic 3hb-oligomers. although it did not degrade crystalline poly(3-hydroxybutyrate) (phb), the purified enzyme degraded artificial amorphous phb at a rate similar to that of the previously identified intracellular phb (iphb) depolymerase (phaz1(reu)). the enzyme appeared to be an en ... | 2003 | 12775684 |
| crystal structure of d-hydantoinase from burkholderia pickettii at a resolution of 2.7 angstroms: insights into the molecular basis of enzyme thermostability. | d-hydantoinase (d-hyd) is an industrial enzyme that is widely used in the production of d-amino acids which are precursors for semisynthesis of antibiotics, peptides, and pesticides. this report describes the crystal structure of d-hydantoinase from burkholderia pickettii (hyd(bp)) at a 2.7-a resolution. the structure of hyd(bp) consists of a core (alpha/beta)(8) triose phosphate isomerase barrel fold and a beta-sheet domain, and the catalytic active site consists of two metal ions and six highl ... | 2003 | 12837777 |
| use of amplified ribosomal dna restriction analysis for identification of ralstonia and pandoraea species: interest in determination of the respiratory bacterial flora in patients with cystic fibrosis. | the recovery of ralstonia and pandoraea species from respiratory tract cultures of patients with cystic fibrosis has recently been reported. these species are difficult to identify, and especially to differentiate from burkholderia cepacia complex organisms, with classical methods. the discriminatory power of amplified ribosomal dna restriction analysis (ardra) within the two genera was assessed by comparing the restriction profiles of reference strains of each species by using a panel of six en ... | 2003 | 12843108 |
| quantitative structure-activity relationship (qsar) analysis of aromatic effector specificity in ntrc-like transcriptional activators from aromatic oxidizing bacteria. | a quantitative structure-activity relationship (qsar) approach was taken to provide mechanistic insights into the interaction between the chemical structure of inducing compounds and the transcriptional activation of aromatic monooxygenase operons among the xylr/dmpr subclass of bacterial ntrc-like transcriptional regulators. compared to xylr and dmpr, a broader spectrum of effector compounds was observed for the tbut system from ralstonia pickettii pko1. the results of qsar analysis for tbut su ... | 2003 | 12855166 |
| substrate inhibition kinetics for toluene and benzene degrading pure cultures and a method for collection and analysis of respirometric data for strongly inhibited cultures. | we present an evaluation of the qualitative and quantitative effects that high concentrations of benzene and toluene have on the growth rate of several pure cultures that use these compounds as their sole carbon and energy source. the cultures employed were five widely studied environmental isolates: pseudomonas putida f1, p. putida mt2, p. mendocina kr, ralstonia pickettii pko1, and burkholderia cepacia g4. three cultures degraded toluene following a pattern consistent with the kinetic model of ... | 2003 | 12889020 |
| classification of ralstonia pickettii-like isolates from the environment and clinical samples as ralstonia insidiosa sp. nov. | thirteen ralstonia pickettii-like isolates from the environment (water, soil and activated sludge) and human clinical samples (including respiratory secretions of cystic fibrosis patients) were investigated in a polyphasic taxonomic study that employed 16s rdna sequence analysis, dna-dna hybridization, determination of dna base composition, whole-cell protein analysis, biochemical characterization and pcr-based assays. all isolates were classified as a novel ralstonia species, for which the name ... | 2003 | 12892129 |
| population pharmacokinetics of ciprofloxacin in pediatric and adolescent patients with acute infections. | the aim of the present study was to characterize the population pharmacokinetics of ciprofloxacin in patients with and without cystic fibrosis ranging in age from 1 day to 24 years and to propose a limited sampling strategy to estimate individual pharmacokinetic parameters. patients were divided into four groups according to the treatment schedule. they received ciprofloxacin by intravenous infusion (30 min) or by the oral route. the number of samples collected from each patient ranged from 1 to ... | 2003 | 14506027 |
| identifying antimicrobial resistance genes with dna microarrays. | we developed and tested a glass-based microarray suitable for detecting multiple tetracycline (tet) resistance genes. microarray probes for 17 tet genes, the beta-lactamase bla(tem-1) gene, and a 16s ribosomal dna gene (escherichia coli) were generated from known controls by pcr. the resulting products (ca. 550 bp) were applied as spots onto epoxy-silane-derivatized, teflon-masked slides by using a robotic spotter. dna was extracted from test strains, biotinylated, hybridized overnight to indivi ... | 2003 | 14506043 |
| rapid screening for freshwater bacterial groups by using reverse line blot hybridization. | the identification of phylogenetic clusters of bacteria that are common in freshwater has provided a basis for probe design to target important freshwater groups. we present a set of 16s ribosomal rna gene-based oligonucleotide probes specific for 15 of these freshwater clusters. the probes were applied in reverse line blot hybridization, a simple method that enables the rapid screening of pcr products from many samples against an array of probes. the optimized assay was made stringent to discri ... | 2003 | 14532039 |
| use of 16s rrna gene sequencing for rapid identification and differentiation of burkholderia pseudomallei and b. mallei. | burkholderia pseudomallei and b. mallei, the causative agents of melioidosis and glanders, respectively, are designated category b biothreat agents. current methods for identifying these organisms rely on their phenotypic characteristics and an extensive set of biochemical reactions. we evaluated the use of 16s rrna gene sequencing to rapidly identify these two species and differentiate them from each other as well as from closely related species and genera such as pandoraea spp., ralstonia spp. ... | 2003 | 14532197 |
| usefulness of rpob gene sequencing for identification of afipia and bosea species, including a strategy for choosing discriminative partial sequences. | bacteria belonging to the genera afipia and bosea are amoeba-resisting bacteria that have been recently reported to colonize hospital water supplies and are suspected of being responsible for intensive care unit-acquired pneumonia. identification of these bacteria is now based on determination of the 16s ribosomal dna sequence. however, the 16s rrna gene is not polymorphic enough to ensure discrimination of species defined by dna-dna relatedness. the complete rpob sequences of 20 strains were fi ... | 2003 | 14602635 |
| efficient degradation of 2,4,6-trichlorophenol requires a set of catabolic genes related to tcp genes from ralstonia eutropha jmp134(pjp4). | 2,4,6-trichlorophenol (2,4,6-tcp) is a hazardous pollutant. several aerobic bacteria are known to degrade this compound. one of these, ralstonia eutropha jmp134(pjp4), a well-known, versatile chloroaromatic compound degrader, is able to grow in 2,4,6-tcp by converting it to 2,6-dichlorohydroquinone, 6-chlorohydroxyquinol, 2-chloromaleylacetate, maleylacetate, and beta-ketoadipate. three enzyme activities encoded by tcp genes, 2,4,6-tcp monooxygenase (tcpa), 6-chlorohydroxyquinol 1,2-dioxygenase ... | 2003 | 14660355 |
| dna fingerprinting of ralstonia paucula by infrequent-restriction-site pcr and randomly amplified polymorphic dna analysis. | ralstonia paucula (formerly cdc group iv c-2) is an environmental organism that can cause serious human infections, occasionally clusters of nosocomial infections. in the present work, 26 strains of r. paucula (4 from the american centers for disease control and prevention collection, 10 from the belgian laboratorium voor microbiologie [lmg] collection, and 12 french clinical isolates) were analyzed with infrequent-restriction-site pcr and randomly amplified polymorphic dna analysis. both techni ... | 2003 | 14662974 |
| effect of temperature and dissolved oxygen on the growth kinetics of pseudomonas putida f1 growing on benzene and toluene. | batch experiments were conducted to determine the effect of temperature and dissolved oxygen concentration on the rates of growth and substrate (benzene and toluene) degradation by the toluene degrading strain, pseudomonas putida f1. over a range of temperature from 15 to 35 degrees c the maximum specific growth rate followed the topiwala-sinclair relationship when either benzene or toluene served as the sole carbon and energy source. oxygen limited growth followed monod saturation kinetics with ... | 2004 | 14664855 |
| structural bases for crmp function in plexin-dependent semaphorin3a signaling. | collapsin response mediator proteins (crmps) are cytosolic phosphoproteins involved in neuronal differentiation and axonal guidance. crmp2 was previously shown to mediate the repulsive effect of sema3a on axons and to participate in axonal specification. the x-ray crystal structure of murine crmp1 was determined at 2.1 a resolution and demonstrates that crmp1 is a bilobed 'lung-shaped' protein forming a tetrameric assembly. structure-based mutagenesis of surface-exposed residues was employed to ... | 2004 | 14685275 |
| structural bases for crmp function in plexin-dependent semaphorin3a signaling. | collapsin response mediator proteins (crmps) are cytosolic phosphoproteins involved in neuronal differentiation and axonal guidance. crmp2 was previously shown to mediate the repulsive effect of sema3a on axons and to participate in axonal specification. the x-ray crystal structure of murine crmp1 was determined at 2.1 a resolution and demonstrates that crmp1 is a bilobed 'lung-shaped' protein forming a tetrameric assembly. structure-based mutagenesis of surface-exposed residues was employed to ... | 2004 | 14685275 |
| ralstonia pickettii outbreak associated with contaminated distilled water used for respiratory care in a paediatric intensive care unit. | 2004 | 14706279 | |
| identification and susceptibility testing of enterobacteriaceae and pseudomonas aeruginosa by direct inoculation from positive bactec blood culture bottles into vitek 2. | inoculation of an automated system for rapid identification (id) and antimicrobial susceptibility testing (ast) directly from positive blood culture bottles will reduce the turnaround time of laboratory diagnosis of septicemic patients, which benefits clinical outcome and decreases patient costs. direct test results, however, must always be confirmed by testing a pure overnight culture, which is the "gold standard." we studied the accuracy of direct testing versus repeat testing in order to inve ... | 2004 | 14715724 |
| detection of the bacillus anthracis gyra gene by using a minor groove binder probe. | identification of chromosomal markers for rapid detection of bacillus anthracis is difficult because significant chromosomal homology exists among b. anthracis, bacillus cereus, and bacillus thuringiensis. we evaluated the bacterial gyra gene as a potential chromosomal marker for b. anthracis. a real-time pcr assay was developed for the detection of b. anthracis. after analysis of the unique nucleotide sequence of the b. anthracis gyra gene, a fluorescent 3' minor groove binding probe was tested ... | 2004 | 14715750 |
| smallpox and pan-orthopox virus detection by real-time 3'-minor groove binder taqman assays on the roche lightcycler and the cepheid smart cycler platforms. | we designed, optimized, and extensively tested several sensitive and specific real-time pcr assays for rapid detection of both smallpox and pan-orthopox virus dnas. the assays are based on taqman 3'-minor groove binder chemistry and were performed on both the rapid-cycling roche lightcycler and the cepheid smart cycler platforms. the hemagglutinin (ha) j7r, b9r, and b10r genes were used as targets for the variola virus-specific assays, and the ha and dna polymerase-e9l genes were used as targets ... | 2004 | 14766823 |
| outbreak of infusion-related septicemia by ralstonia pickettii in the oncology department. | hospital acquired blood stream infection by ralstonia pickettii in 9 cancer patients related to the heparin solution contamination used to flush the central venous catheter. | 2003 | 14870792 |
| trichloroethylene degradation by toluene-oxidizing bacteria grown on non-aromatic substrates. | the potential of trichloroethylene (tce) to induce and non-aromatic growth substrates to support tce degradation in five strains (pseudomonas mendocina kr1, ralstonia pickettii pko1, pseudomonas putida f1, burkholderia cepacia g4, b. cepacia pr1) of toluene-oxidizing bacteria was examined. lb broth and acetate did not support tce degradation in any of the wild-type strains. in contrast, fructose supported the highest specific levels of tce oxidation observed in each of the strains tested, except ... | 2004 | 14971854 |
| real-time multiplex pcr assay for detection of brucella spp., b. abortus, and b. melitensis. | the identification of brucella can be a time-consuming and labor-intensive process that places personnel at risk for laboratory-acquired infection. here, we describe a real-time pcr assay for confirmation of presumptive brucella isolates. the assay was designed in a multiplex format that will allow the rapid identification of brucella spp., b. abortus, and b. melitensis in a single test. | 2004 | 15004098 |
| aerobic and anaerobic toluene degradation by a newly isolated denitrifying bacterium, thauera sp. strain dnt-1. | a newly isolated denitrifying bacterium, thauera sp. strain dnt-1, grew on toluene as the sole carbon and energy source under both aerobic and anaerobic conditions. when this strain was cultivated under oxygen-limiting conditions with nitrate, first toluene was degraded as oxygen was consumed, while later toluene was degraded as nitrate was reduced. biochemical observations indicated that initial degradation of toluene occurred through a dioxygenase-mediated pathway and the benzylsuccinate pathw ... | 2004 | 15006757 |
| wautersia gen. nov., a novel genus accommodating the phylogenetic lineage including ralstonia eutropha and related species, and proposal of ralstonia [pseudomonas] syzygii (roberts et al. 1990) comb. nov. | comparative 16s rdna sequence analysis indicates that two distinct sublineages, with a sequence dissimilarity of >4 % (bootstrap value, 100 %), exist within the genus ralstonia: the ralstonia eutropha lineage, which comprises ralstonia basilensis, ralstonia campinensis, r. eutropha, ralstonia gilardii, ralstonia metallidurans, ralstonia oxalatica, ralstonia paucula, ralstonia respiraculi and ralstonia taiwanensis; and the ralstonia pickettii lineage, which comprises ralstonia insidiosa, ralstoni ... | 2004 | 15023939 |
| simultaneous degradation of atrazine and phenol by pseudomonas sp. strain adp: effects of toxicity and adaptation. | the strain pseudomonas sp. strain adp is able to degrade atrazine as a sole nitrogen source and therefore needs a single source for both carbon and energy for growth. in addition to the typical c source for pseudomonas, na(2)-succinate, the strain can also grow with phenol as a carbon source. phenol is oxidized to catechol by a multicomponent phenol hydroxylase. catechol is degraded via the ortho pathway using catechol 1,2-dioxygenase. it was possible to stimulate the strain in order to degrade ... | 2004 | 15066779 |
| microorganisms resistant to free-living amoebae. | free-living amoebae feed on bacteria, fungi, and algae. however, some microorganisms have evolved to become resistant to these protists. these amoeba-resistant microorganisms include established pathogens, such as cryptococcus neoformans, legionella spp., chlamydophila pneumoniae, mycobacterium avium, listeria monocytogenes, pseudomonas aeruginosa, and francisella tularensis, and emerging pathogens, such as bosea spp., simkania negevensis, parachlamydia acanthamoebae, and legionella-like amoebal ... | 2004 | 15084508 |
| toluene 3-monooxygenase of ralstonia pickettii pko1 is a para-hydroxylating enzyme. | oxygenases are promising biocatalysts for performing selective hydroxylations not accessible by chemical methods. whereas toluene 4-monooxygenase (t4mo) of pseudomonas mendocina kr1 hydroxylates monosubstituted benzenes at the para position and toluene ortho-monooxygenase (tom) of burkholderia cepacia g4 hydroxylates at the ortho position, toluene 3-monooxygenase (t3mo) of ralstonia pickettii pko1 was reported previously to hydroxylate toluene at the meta position, producing primarily m-cresol ( ... | 2004 | 15126473 |
| addition of aromatic substrates restores trichloroethylene degradation activity in pseudomonas putida f1. | the rate of trichloroethylene (tce) degradation by toluene dioxygenase (tdo) in resting cells of pseudomonas putida f1 gradually decreased and eventually stopped within 1.5 h, as in previous reports. however, the subsequent addition of toluene, which is the principal substrate of tdo, resulted in its immediate degradation without a lag phase. after the consumption of toluene, degradation of tce restarted at a rate similar to its initial degradation, suggesting that this degradation was mediated ... | 2004 | 15128539 |
| biochemical characterization of the naturally occurring oxacillinase oxa-50 of pseudomonas aeruginosa. | the bla(oxa-50) gene (formerly known as the pa5514 gene) is an oxacillinase gene identified in silico in the genome of pseudomonas aeruginosa pao1. by using a mutant strain of p. aeruginosa pao1 that had an inactivated bla(ampc) cephalosporinase gene, the bla(oxa-50) gene was shown to be expressed constitutively in p. aeruginosa. this beta-lactamase gene was cloned onto a multicopy plasmid and expressed in p. aeruginosa and escherichia coli. it conferred decreased susceptibility to ampicillin an ... | 2004 | 15155197 |
| 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 |
| saturation mutagenesis of toluene ortho-monooxygenase of burkholderia cepacia g4 for enhanced 1-naphthol synthesis and chloroform degradation. | directed evolution of toluene ortho-monooxygenase (tom) of burkholderia cepacia g4 previously created the hydroxylase alpha-subunit (toma3) v106a variant (tom-green) with increased activity for both trichloroethylene degradation (twofold enhancement) and naphthalene oxidation (six-times-higher activity). in the present study, saturation mutagenesis was performed at position a106 with escherichia coli tg1/pbs(kan)tomv106a to improve tom activity for both chloroform degradation and naphthalene oxi ... | 2004 | 15184118 |
| protein engineering of toluene-o-xylene monooxygenase from pseudomonas stutzeri ox1 for synthesizing 4-methylresorcinol, methylhydroquinone, and pyrogallol. | toluene-o-xylene monooxygenase (tomo) from pseudomonas stutzeri ox1 oxidizes toluene to 3- and 4-methylcatechol and oxidizes benzene to form phenol; in this study tomo was found to also form catechol and 1,2,3-trihydroxybenzene (1,2,3-thb) from phenol. to synthesize novel dihydroxy and trihydroxy derivatives of benzene and toluene, dna shuffling of the alpha-hydroxylase fragment of tomo (toua) and saturation mutagenesis of the toua active site residues i100, q141, t201, and f205 were used to gen ... | 2004 | 15184119 |
| vertical transmission of endobacteria in the arbuscular mycorrhizal fungus gigaspora margarita through generation of vegetative spores. | arbuscular mycorrhizal (am) fungi living in symbiotic association with the roots of vascular plants have also been shown to host endocellular rod-shaped bacteria. based on their ribosomal sequences, these endobacteria have recently been identified as a new taxon, candidatus glomeribacter gigasporarum. in order to investigate the cytoplasmic stability of the endobacteria in their fungal host and their transmission during am fungal reproduction (asexual), a system based on transformed carrot roots ... | 2004 | 15184163 |
| altering toluene 4-monooxygenase by active-site engineering for the synthesis of 3-methoxycatechol, methoxyhydroquinone, and methylhydroquinone. | wild-type toluene 4-monooxygenase (t4mo) of pseudomonas mendocina kr1 oxidizes toluene to p-cresol (96%) and oxidizes benzene sequentially to phenol, to catechol, and to 1,2,3-trihydroxybenzene. in this study t4mo was found to oxidize o-cresol to 3-methylcatechol (91%) and methylhydroquinone (9%), to oxidize m-cresol and p-cresol to 4-methylcatechol (100%), and to oxidize o-methoxyphenol to 4-methoxyresorcinol (87%), 3-methoxycatechol (11%), and methoxyhydroquinone (2%). apparent vmax values of ... | 2004 | 15231803 |
| oxidation of benzene to phenol, catechol, and 1,2,3-trihydroxybenzene by toluene 4-monooxygenase of pseudomonas mendocina kr1 and toluene 3-monooxygenase of ralstonia pickettii pko1. | aromatic hydroxylations are important bacterial metabolic processes but are difficult to perform using traditional chemical synthesis, so to use a biological catalyst to convert the priority pollutant benzene into industrially relevant intermediates, benzene oxidation was investigated. it was discovered that toluene 4-monooxygenase (t4mo) of pseudomonas mendocina kr1, toluene 3-monooxygenase (t3mo) of ralstonia pickettii pko1, and toluene ortho-monooxygenase (tom) of burkholderia cepacia g4 conv ... | 2004 | 15240250 |