| cadmium(ii) speciation in complex aquatic systems: a study with ferrihydrite, bacteria, and an organic ligand. | understanding the chemical interactions that occur in complex natural systems is fundamental to their management in this work the distribution of cadmium in the presence of phthalic acid (h2lp), ferrihydrite, and bacteria cells (comamonas spp., heat killed) was measured and modeled for systems with incrementally increasing complexity. in binary systems, cadmium adsorption onto bacteria or ferrihydrite was accurately predicted using the nonelectrostatic four site model (nfsm) and the diffuse laye ... | 2009 | 19848157 |
| comparative phylogenies of burkholderia, ralstonia, comamonas, brevundimonas and related organisms derived from rpob, gyrb and rrs gene sequences. | phylogenetic analysis of strains from burkholderia, ralstonia, cupriavidus, comamonas, delftia, acidovorax, brevundimonas, herbaspirillum huttiense and "pseudomonas butanovora" was performed based on the protein-coding genes rpob and gyrb and on the 16s rrna-coding gene rrs. overall, the phylogenies deduced from the three genes were concordant among themselves and with current taxonomy. however, a few differences among individual gene phylogenies were noted. for example, the separation of cupria ... | 2008 | 18280706 |
| comamonas granuli sp. nov., isolated from granules used in a wastewater treatment plant. | a gram-negative, motile, rod-shaped, non-spore-forming bacterial strain, designated as ko03(t), was isolated from microbial granules, and was characterized, using a polyphasic approach, in order to determine its taxonomic position. the isolate was positive for catalase and oxidase, but negative for gelatinase and beta-galactosidase. phylogenetic analyses using the 16s rrna gene sequence showed that the strain formed a monophyletic branch towards the periphery of the evolutionary radiation occupi ... | 2008 | 18758728 |
| fe(iii)-enhanced anaerobic transformation of 2,4-dichlorophenoxyacetic acid by an iron-reducing bacterium comamonas koreensis cy01. | this work studied the ability of comamonas koreensis cy01 to reduce fe(iii) (hydr)oxides by coupling the oxidation of electron donors and the enhanced biodegradation of 2,4-dichlorophenoxyacetic acid (2,4-d) by the presence of fe(iii) (hydr)oxides. the experimental results suggested that strain cy01 can utilize ferrihydrite, goethite, lepidocrocite or hematite as the terminal electron acceptor and citrate, glycerol, glucose or sucrose as the electron donor. strain cy01 could transform 2,4-d to 4 ... | 2010 | 19895639 |
| the role of humic substances in the anaerobic reductive dechlorination of 2,4-dichlorophenoxyacetic acid by comamonas koreensis strain cy01. | the role of the humic model compound, anthraquinone-2,6-disulfonate (aqds), in the anaerobic reductive dechlorination of 2,4-dichlorophenoxyacetic acid (2,4-d) by the fe(iii)- and humic substances (hs)-reducing bacterium, comamonas koreensis strain cy01 was investigated. the results taken as a whole indicated that (i) strain cy01 could couple glucose oxidation to 2,4-d reductive dechlorination; (ii) reductive dechlorination of 2,4-d by strain cy01 was greatly stimulated by the addition of aqds; ... | 2009 | 18849114 |
| characterization of the isophthalate degradation genes of comamonas sp. strain e6. | the isophthalate (ipa) degradation gene cluster (iphacbdr) responsible for the conversion of ipa into protocatechuate (pca) was isolated from comamonas sp. strain e6, which utilizes phthalate isomers as sole carbon and energy sources via the pca 4,5-cleavage pathway. based on amino acid sequence similarity, the ipha, iphc, iphb, iphd, and iphr genes were predicted to code for an oxygenase component of ipa dioxygenase (ipado), a periplasmic ipa binding receptor, a 1,2-dihydroxy-3,5-cyclohexadiene ... | 2010 | 19933340 |
| novel tn4371-ice like element in ralstonia pickettii and genome mining for comparative elements. | integrative conjugative elements (ices) are important factors in the plasticity of microbial genomes. an element related to the ice tn4371 was discovered during a bioinformatic search of the ralstonia pickettii 12j genome. this element was analysed and further searches carried out for additional elements.a pcr method was designed to detect and characterise new elements of this type based on this scaffold and a culture collection of fifty-eight ralstonia pickettii and ralstonia insidiosa strains ... | 2009 | 19941653 |
| regulation of testosterone degradation in comamonas testosteroni. | recently, we have identified a gene encoding a luxr-type factor, teir (testosterone-inducible regulator), which positively regulates steroid degradation in comamonas testosteroni. herein, we demonstrate that teir interacts in vivo with steroid catabolic gene promoters. the presence of testosterone induces a significant teir protein increase at the early logarithmic phase of growth. interestingly, it is not until the early stationary phase where the activation of a steroid-inducible gene promoter ... | 2008 | 18852046 |
| cis- and trans-regulatory elements of 3alpha-hydroxysteroid dehydrogenase/carbonyl reductase as biosensor system for steroid determination in the environment. | 3alpha-hydroxysteroid dehydrogenase/carbonyl reductase from comamonas testosteroni is a key enzyme in the degradation of steroids in the environment. the encoding gene, hsda, is expressed only at very low levels in the absence of steroids, but undergoes a several fold induction in the presence of steroid substrates. in previous investigations, we have elucidated the mechanism of hsda regulation that involves several activators and repressors. in the present study, the hsda gene was replaced by t ... | 2009 | 19000658 |
| molecular diversity of katg genes in the soil bacteria comamonas. | three complete katg genes coding for bifunctional catalase-peroxidases (katgs) from the beta-proteobacterium comamonas terrigena and two related strains of comamonas testosteroni have been cloned and sequenced. catalase-peroxidases are unique bifunctional enzymes known to be expressed in these soil bacteria in response to environmental and/or oxidative stress. the evolutionary and structural diversity of these enzymes is investigated based on multiple sequence alignment and comprehensive phyloge ... | 2010 | 20062977 |
| dissecting the paradoxical effects of hydrogen bond mutations in the ketosteroid isomerase oxyanion hole. | the catalytic importance of enzyme active-site interactions is frequently assessed by mutating specific residues and measuring the resulting rate reductions. this approach has been used in bacterial ketosteroid isomerase to probe the energetic importance of active-site hydrogen bonds donated to the dienolate reaction intermediate. the conservative tyr16phe mutation impairs catalysis by 10(5)-fold, far larger than the effects of hydrogen bond mutations in other enzymes. however, the less-conserva ... | 2010 | 20080683 |
| 3alpha-hydroxysteroid dehydrogenase/carbonyl reductase as a tool for isolation and characterization of a new marine steroid degrading bacterial strain. | steroid contamination of sea water is an ever growing problem and impacts population dynamics of all kinds of sea animals. we have long experience with the soil bacterium comamonas testosteroni which is able to catabolize a variety of steroids and polycyclic aromatic hydrocarbons, and which might be used in the bioremediation of contaminated soil. for our studies, we use 3alpha-hydroxysteroid dehydrogenase/carbonyl reductase (3 alpha-hsd/cr) as an indicator system, since it is a key enzyme in ad ... | 2009 | 19026617 |
| characterization of extracellular polymeric substances from denitrifying organism comamonas denitrificans. | extracellular polymeric substances (eps) play an important role in the formation and activity of biofilms in wastewater treatment (wwt). the eps of the denitrifying biomarker comamonas denitrificans strain 110, produced in different culture media and growth modes, were characterized. the eps mainly contained protein (3-37%), nucleic acids (9-50%), and carbohydrates (3-21%). the extracellular dna was found to be important for initial biofilm formation since biofilm, but not planktonic growth, was ... | 2009 | 19123000 |
| class 1 integrons in benthic bacterial communities: abundance, association with tn402-like transposition modules and evidence for coselection with heavy-metal resistance. | the integron/gene cassette system contributes to lateral gene transfer of genetic information in bacterial communities, with gene cassette-encoded proteins potentially playing an important role in adaptation to stress. class 1 integrons are a particularly important class as they themselves seem to be broadly disseminated among the proteobacteria and have an established role in the spread of antibiotic resistance genes. the abundance and structure of class 1 integrons in freshwater sediment bacte ... | 2010 | 20132306 |
| monitoring the bacterial community dynamics in a petroleum refinery wastewater membrane bioreactor fed with a high phenolic load. | the phenolic compounds are a major contaminant class often found in industrial wastewaters and the biological treatment is an alternative tool commonly employed for their removal. in this sense, monitoring microbial community dynamics is crucial for a successful wastewater treatment. this work aimed to monitor the structure and activity of the bacterial community during the operation of a laboratory-scale continuous submerged membrane bioreactor (smbr), using pcr and rt-pcr followed by denaturin ... | 2010 | 20134229 |
| identification of genes involved in inversion of stereochemistry of a c-12 hydroxyl group in the catabolism of cholic acid by comamonas testosteroni ta441. | comamonas testosteroni ta441 degrades steroids such as testosterone via aromatization of the a ring, followed by meta-cleavage of the ring. in the dna region upstream of the meta-cleavage enzyme gene tesb, two genes required during cholic acid degradation for the inversion of an alpha-oriented hydroxyl group on c-12 were identified. a dehydrogenase, stea, converts 7 alpha,12 alpha-dihydroxyandrosta-1,4-diene-3,17-dione to 7 alpha-hydroxyandrosta-1,4-diene-3,12,17-trione, and a hydrogenase, steb, ... | 2008 | 18539741 |
| comamonas zonglianii sp. nov., isolated from phenol-contaminated soil. | a bacterial strain, designated bf-3(t), was isolated from phenol-contaminated soil and investigated using a polyphasic taxonomic approach. cells were gram-reaction-negative, non-sporulating, non-motile, short rods. phylogenetic analysis based on 16s rrna gene sequences showed that strain bf-3(t) formed a monophyletic branch at the periphery of the evolutionary radiation occupied by the genus comamonas; it showed highest sequence similarities to comamonas aquatica lmg 2370(t) (96.8 %), c. nitrati ... | 2011 | 20207803 |
| diversity of microbes and potential exoelectrogenic bacteria on anode surface in microbial fuel cells. | single-chamber microbial fuel cells (mfcs), inoculated with anaerobic sludge and continuously run with two kinds of organic wastewater influents, were systemically investigated. the diversity of microbes, determined by 16s rdna analysis, was analyzed on three anodes under different conditions. one anode was in a closed circuit in synthetic wastewater containing glucose. the other two anodes, in open or closed circuits, were fed effluent from an anaerobic reactor treating starch wastewater. the c ... | 2010 | 20339216 |
| [isolation and identification of phenol-degrading strains and the application in biotreatment of phenol-containing wastewater]. | ten phenol-degrading bacterial strains were isolated from mixture of activated sludge and wastewater of a petroleum chemical plant. the five isolates (pd1, pd2, pd6, pd7 and pd39) were identified as pseudomonas sp.,the four (pd4, pd5, pd8 and pd9) as acinetobacter sp.,and the one (pd3) as comamonas sp.by 16s rdna sequence. biodegradation characteristics of phenol, optimal conditions for growth, substrate range, activities of catechol 1,2-dioxygenase and catechol 2,3-dioxygenase, and biotreatment ... | 2008 | 18613524 |
| degradation of quinoline by immobilized comamonas acidovorans in a three-phase airlift reactor. | quinolie degradation by comamonas acidovorans was studied in a continuously operated three-phase airlift reactor. porous glass beads were applied as support matrix for cell imobilization by colonization. under steady-state conditions (s approximately 0), cell attachment was poor at low dilution rates but imporved considerably with increasing dilution rate. conversion of quinoline was investigated below and above the washout for suspended culture (d(crit) = mu(max) = 0.42 h(-1)). with immobilized ... | 1995 | 18623265 |
| impact of mutation on proton transfer reactions in ketosteroid isomerase: insights from molecular dynamics simulations. | the two proton transfer reactions catalyzed by ketosteroid isomerase (ksi) involve a dienolate intermediate stabilized by hydrogen bonds with tyr14 and asp99. molecular dynamics simulations based on an empirical valence bond model are used to examine the impact of mutating these residues on the hydrogen-bonding patterns, conformational changes, and van der waals and electrostatic interactions during the proton transfer reactions. while the rate constants for the two proton transfer steps are sim ... | 2010 | 20450180 |
| performance of three phase fluidized bed reactor for quinoline degradation on various supports at steady state and dynamic conditions. | quinoline degradation by comamonas acidovorans was investigated in a three phase fluidized bed reactor at dilution rates below and above the critical value (micro(max) = 0.42 h(-1)). quinoline was used as the sole source of carbon, nitrogen, and energy. two attachment carriers, polyurethane foam (bayvitec) and modified cellulose (aquacel), and a gel entrapment carrier (polyvinyl alcohol) were studied and compared with regard to their effectiveness to immobilize cells. attachment and biofilm form ... | 1997 | 18636645 |
| pha-accumulating microorganisms in full-scale wastewater treatment plants. | a study was conducted to clarify phylogenetic affiliations of polyhydroxyalkanoate (pha)-accumulating microorganisms in full-scale activated sludge processes. activated sludge samples obtained from three full-scale activated sludge processes were aerobically incubated with excess acetate to increase their pha content. the buoyant density separation method was applied to selectively collect pha-accumulating cells, which were then analysed by the group-level fish and the pcr-dgge-sequencing method ... | 2008 | 18653931 |
| identifying competing aerobic nitrobenzene biodegradation pathways by compound-specific isotope analysis. | nitroaromatic compounds that contaminate soil and groundwater can be biodegraded by different, sometimes competing reaction pathways. we evaluated the combined use of compound-specific stable c and n isotope analysis to distinguish between enzymatic nitrobenzene oxidation by comamonas sp. strain js765 and partial reduction by pseudomonas pseudoalcaligenes strain js45 under aerobic conditions. bulk 13c and 15n enrichment factors for nitrobenzene dioxygenation with js765 were -3.9 per thousand +/- ... | 2008 | 18678003 |
| [microbial community structure of beer wastewater treatment plants analyzed by pcr-dgge technique]. | the microbial community structure of beer wastewater treatment plants with hydrolyze-acidification and sbr process was studied by pcr amplification and denaturing gradient gel electrophoresis (dgge) based 16s rdna. activated sludge samples were collected from both hydrolyze-acidification tank and sbr tank at different depth and disposal period. the total dna was extracted and the 16s rdna was amplified by universal primer. the microbial community structure was analyzed by denaturing gradient gel ... | 2008 | 19143400 |
| response to mixed substrate feeds of the structure and activity of a linuron-degrading triple-species biofilm. | we sought to determine whether the pesticide-degrading performance of a multi-species bacterial biofilm is affected by co-occurrence of multiple nutrient sources. thus, the 3-(3,4-dichlorophenyl)-1-methoxy-1-methyl urea (linuron)-degrading activity of a triple-species linuron-degrading consortium, cultivated in continuous flow biofilm systems, was monitored when exposed to mixed substrate feeds which contained, in addition to linuron, readily assimilated carbon (i.e. citrate and trypticase soy b ... | 2010 | 20600856 |
| transcriptional regulation of the terephthalate catabolism operon in comamonas sp. strain e6. | two almost identical gene clusters, tphr(i)c(i)a2(i)a3(i)b(i)a1(i) and tphr(ii)c(ii)a2(ii)a3(ii)b(ii)a1(ii), are responsible for the conversion of terephthalate (tpa) to protocatechuate in comamonas sp. strain e6. in the present study, we investigated the transcriptional regulation of the tphr(ii)c(ii)a2(ii)a3(ii)b(ii)a1(ii) gene cluster. reverse transcription-pcr analysis suggested that the tphr(ii)c(ii)a2(ii)a3(ii)b(ii)a1(ii) genes form two transcriptional units, the tphc(ii)a2(ii)a3(ii)b(ii)a ... | 2010 | 20656871 |
| [the midgut bacterial flora in lab-reared anopheles sinensis]. | to screen gram-negative bacteria in the midguts of lab-reared anopheles sinensis at 3 development stages (larva, unfed adult and engorged adult). | 2010 | 20666322 |
| isolates of comamonas spp. exhibiting catalase and peroxidase activities and diversity of their responses to oxidative stress. | for survival isolates of comamonas testosteroni ccm 1931, c. testosteroni k3, c. terrigena n3h or n1c and c. terrigena ccm 2409, selected largely from polluted environments, the production of catalase and dianisidine-peroxidase activity was important. electrophoretic resolution of cell-free extracts of aerobically grown strains in luria-bertani medium during the exponential phase revealed distinctive expression of catalatic and peroxidatic activities detected with 3,3'-diaminobenzidine tetrahydr ... | 2010 | 20678795 |
| thiosulfate oxidation by comamonas sp. s23 isolated from a sulfur spring. | a bacterial isolate s23 capable of oxidizing thiosulfate was isolated from a sulfur spring. strain s23 is gram-negative, aerobic, and motile. the g + c content of dna is 61.4 mol%. the fatty acid composition and phylogenetic analysis of the 16s rrna gene sequence of strain s23 showed that it is related to the members of the genus comamonas, and most closely related to comamonas testosteroni (99.9% sequence similarity). the isolate s23 exhibited thiosulfate oxidation under a mixotrophic growth co ... | 2009 | 19189181 |
| potential of escherichia coli o157:h7 to persist and form viable but non-culturable cells on a food-contact surface subjected to cycles of soiling and chemical treatment. | our aim was to assess the potential of escherichia coli o157:h7 to persist in a processing environment. we studied e. coli behaviour under conditions modelling those of meat plants to establish one initial bacterial load that allows persistence and another that does not. polyurethane coupons (3.5 cm²) were contaminated once with e. coli in meat exudate before being subjected daily to a cleaning product and a disinfectant, both at half the recommended in-use concentrations, and a further soiling ... | 2010 | 20888655 |
| characterization of the protocatechuate 4,5-cleavage pathway operon in comamonas sp. strain e6 and discovery of a novel pathway gene. | the protocatechuate (pca) 4,5-cleavage (pca45) pathway is the essential catabolic route for the degradation of various aromatic acids in the genus comamonas. all of the pca45 pathway genes, orf1-pmdkefdabc, as well as another pca 4,5-dioxygenase gene, pmda(ii)b(ii), were isolated from a phthalate-degrading bacterium, comamonas sp. strain e6. disruption of pmdb and pmdd in e6, which code for the β subunit of pca 4,5-dioxygenase and 2-pyrone-4,6-dicarboxylate (pdc) hydrolase, respectively, resulte ... | 2010 | 20952641 |
| biodegradation of a biocide (cu-n-cyclohexyldiazenium dioxide) component of a wood preservative by a defined soil bacterial community. | the wood protection industry has refined their products from chrome-, copper-, and arsenate-based wood preservatives toward solely copper-based preservatives in combination with organic biocides. one of these is cu-hdo, containing the chelation product of copper and n-cyclohexyldiazenium dioxide (hdo). in this study, the fate of isotope-labeled ((13)c) and nonlabeled ((12)c) cu-hdo incorporated in wood sawdust mixed with soil was investigated. hdo concentration was monitored by high-pressure liq ... | 2010 | 20952650 |
| human infection with delftia tsuruhatensis isolated from a central venous catheter. | we present the case of a patient with catheter-related infection caused by delftia tsuruhatensis, a newly described species closely related to delftia acidovorans (formerly comamonas acidovorans). to date, d. tsuruhatensis has not been described as a pathogen. to the best of our knowledge, this is the first report describing d. tsuruhatensis as the causative agent of a human infection. | 2010 | 20965913 |
| enhancement of cometabolic biodegradation of 4-chlorophenol induced with phenol and glucose as carbon sources by comamonas testosteroni. | the biological degradation of phenol and 4-chlorophenol (4-cp) by comamonas testosteroni cect 326t has been studied. phenol and 4-cp were treated alone as a sole carbon and energy source, but only phenol was completely degraded by c. testosteroni. since the presence of cosubstrates can enhance the toxic compounds removal by pure cultures, phenol and glucose were added as growth substrates for cometabolic transformation of 4-cp. high efficiencies were obtained in all the experiments carried out i ... | 2010 | 20970917 |
| bioaugmentation of activated sludge towards 3-chloroaniline removal with a mixed bacterial population carrying a degradative plasmid. | a bioaugmentation approach combining several strategies was applied to achieve degradation of 3-chloroaniline (3ca) in semicontinuous activated sludge reactors. in a first step, a 3ca-degrading comamonas testosteroni strain carrying the degradative plasmid pnb2 was added to a biofilm reactor, and complete 3ca degradation together with spread of the plasmid within the indigenous biofilm population was achieved. a second set of reactors was then bioaugmented with either a suspension of biofilm cel ... | 2009 | 19268574 |
| hydrogen bonding in the active site of ketosteroid isomerase: electronic inductive effects and hydrogen bond coupling. | computational studies are performed to analyze the physical properties of hydrogen bonds donated by tyr16 and asp103 to a series of substituted phenolate inhibitors bound in the active site of ketosteroid isomerase (ksi). as the solution pk(a) of the phenolate increases, these hydrogen bond distances decrease, the associated nuclear magnetic resonance (nmr) chemical shifts increase, and the fraction of protonated inhibitor increases, in agreement with prior experiments. the quantum mechanical/mo ... | 2010 | 21049962 |
| the missing link in linear alkylbenzenesulfonate surfactant degradation: 4-sulfoacetophenone as a transient intermediate in the degradation of 3-(4-sulfophenyl)butyrate by comamonas testosteroni kf-1. | biodegradation of the laundry surfactant linear alkylbenzenesulfonate (las) involves complex bacterial communities. the known heterotrophic community has two tiers. first, all las congeners are oxygenated and oxidized to about 50 sulfophenylcarboxylates (spc). second, the spcs are mineralized. comamonas testosteroni kf-1 mineralizes 3-(4-sulfophenyl)butyrate (3-c4-spc). during growth of strain kf-1 with 3-c4-spc, two transient intermediates were detected in the culture medium. one intermediate w ... | 2010 | 19915037 |
| role of s114 in the nadh-induced conformational change and catalysis of 3alpha-hydroxysteroid dehydrogenase/carbonyl reductase from comamonas testosteroni. | 3alpha-hydroxysteroid dehydrogenase/carbonyl reductase reversibly catalyzes the oxidation of androsterone with nad(+) to form androstanedione and nadh. in this study, we characterize the role of the conserved residue s114 in cofactor binding and catalysis, using site-directed mutagenesis, steady-state kinetics, fluorescence quenching and anisotropy measurements. the catalytic efficiency of v/k(nadh)et for wild-type and s114a is 1.5 x10(7) and 3.8 x 10(3) m(-1) s(-1), respectively, suggesting tha ... | 2009 | 19520191 |
| atrazine degradation by a simple consortium of klebsiella sp. a1 and comamonas sp. a2 in nitrogen enriched medium. | a simple consortium consisted of two members of klebsiella sp. a1 and comamonas sp. a2 was isolated from the sewage of a pesticide mill in china. one member of klebsiella sp. a1 is a novel strain that could use atrazine as the sole carbon and nitrogen source. the consortium showed high atrazine-mineralizing efficiency and about 83.3% of 5 g l(-1) atrazine could be mineralized after 24 h degradation. contrary to many other reported microorganisms, the consortium was insensitive to some nitrogenou ... | 2010 | 19603273 |
| heterotrophic nitrification-aerobic denitrification by novel isolated bacteria. | three novel strains capable of heterotrophic nitrification-aerobic denitrification were isolated from the landfill leachate treatment system. based on their phenotypic and phylogenetic characteristics, the isolates were identified as agrobacterium sp. lad9, achromobacter sp. gad3 and comamonas sp. gad4, respectively. batch tests were carried out to evaluate the growth and the ammonia removal patterns. the maximum growth rates as determined from the growth curve were 0.286, 0.228, and 0.433 h(-1) ... | 2010 | 21113643 |
| effects of plant growth promoting rhizobacteria (pgpr) on rooting and root growth of kiwifruit (actinidia deliciosa) stem cuttings. | the effects of plant growth promoting rhizobacteria (pgpr) on the rooting and root growth of semi-hardwood and hardwood kiwifruit stem cuttings were investigated. the pgpr used were bacillus rc23, paenibacillus polymyxa rc05, bacillus subtilis osu142, bacillus rc03, comamonas acidovorans rc41, bacillus megaterium rc01 and bacillus simplex rc19. all the bacteria showed indole-3-acetic acid (iaa) producing capacity. among the pgpr used, the highest rooting ratios were obtained at 47.50% for semi-h ... | 2010 | 21157636 |
| dna-stable isotope probing integrated with metagenomics for retrieval of biphenyl dioxygenase genes from polychlorinated biphenyl-contaminated river sediment. | stable isotope probing with [(13)c]biphenyl was used to explore the genetic properties of indigenous bacteria able to grow on biphenyl in pcb-contaminated river raisin sediment. a bacterial 16s rrna gene clone library generated from [(13)c]dna after a 14-day incubation with [(13)c]biphenyl revealed the dominant organisms to be members of the genera achromobacter and pseudomonas. a library built from pcr amplification of genes for aromatic-ring-hydroxylating dioxygenases from the [(13)c]dna fract ... | 2009 | 19648381 |
| why two are not enough: degradation of p-toluenesulfonate by a bacterial community from a pristine site in moorea, french polynesia. | in previous work, only one culture (strain ta12) from a pristine site was reported to utilize the xenobiotic compound p-toluenesulfonate (tsa) as a sole source of carbon and energy for aerobic growth. 'strain ta12' has now been recognized as a community of three bacteria: achromobacter xylosoxidans ta12-a, ensifer adhaerens ta12-b and pseudomonas nitroreducens ta12-c. achromobacter xylosoxidans ta12-a and e. adhaerens ta12-b were identified as the tsa degraders. these two organisms contain sever ... | 2011 | 21204940 |
| catheter-related bacteremia caused by comamonas testosteroni in a hemodialysis patient. | comamonas testosteroni has rarely been implicated as a human pathogen. in general, the outcome of c. testosteroni infections is favorable. we report a case of fatal bacteremia caused by c. testosteroni in a 64-year-old woman on hemodialysis. | 2011 | 21223488 |
| application of nitroarene dioxygenases in the design of novel strains that degrade chloronitrobenzenes. | widespread application of chloronitrobenzenes as feedstocks for the production of industrial chemicals and pharmaceuticals has resulted in extensive environmental contamination with these toxic compounds, where they pose significant risks to the health of humans and wildlife. while biotreatment in general is an attractive solution for remediation, its effectiveness is limited with chloronitrobenzenes due to the small number of strains that can effectively mineralize these compounds and their abi ... | 2009 | 21261918 |
| steroid degradation and two steroid-inducible enzymes in the marine bacterium h5. | natural and synthetic steroid hormones excreted into the environment are potentially threatening the population dynamics of all kinds of animals and public health. we have previously isolated a steroid degrading bacterial strain (h5) from the baltic sea, at kiel, germany. 16s-rrna analysis showed that bacterial strain h5 belongs to the genus vibrio, family vibrionaceae and class gamma-proteobacteria. bacterial strain h5 can degrade steroids such as testosterone and estrogens, which was shown in ... | 2011 | 21281621 |
| identification of a new steroid degrading bacterial strain h5 from the baltic sea and isolation of two estradiol inducible genes. | the presence of steroid hormones in the aquatic environment is potentially threatening the population dynamics of all kinds of sea animals and public health. environmental estrogens in water have been reported to be associated with abnormal sexual development and abnormal feminizing responses in some animals. new approaches for the bioremediation of steroid hormones from the environment are therefore urgently sought. we have previously isolated a steroid degrading bacterial strain (h5) from the ... | 2011 | 21310233 |
| [isolation, identification of methyl tert-butyl ether degradation strain and its degradation kinetics]. | a methyl tert-butyl ether degradation strain a1 was isolated from the soil under an old gingko tree. it was identified preliminarily as comamonas testosterone by 16s rdna sequence analysis. the main factors including inoculation amount of microbes, ph, temperature and mtbe concentration that may affect the degradation efficiency of mtbe were further studied. the results indicated that the optimum conditions were as following: ph 7.0, temperature 25 degrees c, inoculation amount of microbes was 2 ... | 2009 | 19662869 |
| bacterial community structure and dominant bacteria in activated sludge from a 70 degrees c ultrasound-enhanced anaerobic reactor for treating carbazole-containing wastewater. | status of, and changes in, the bacterial communities at two acclimation stages (with- and without-ultrasound) in a small 70 degrees c ultrasound-enhanced anaerobic reactor for treating carbazole-containing wastewater reactor were analyzed by pcr-dgge and real-time pcr techniques. pcr-dgge results indicated that a large number of bands occurred in the whole sludge samples. pseudomonas sp., comamonas sp., and diaphorobacter sp. were identified as being able to utilize carbazole as a carbon source, ... | 2010 | 19733065 |
| comamonas testosteroni infection in taiwan: reported two cases and literature review. | comamonas testosteroni is a widely distributed aerobic gram-negative bacillus. infection by c testosteroni is infrequent, and no such cases have been reported in taiwan. here, we would like to present a 54-year-old alcoholic patient from taiwan, and his left leg was injured during a fishing trip, resulting in left leg cellulitis and c testosteroni bacteremia. the patient's fever subsided after initial treatment with extended-spectrum cephalosporin, whereas his erythematous swelling did not resol ... | 2011 | 21531356 |
| comamonas testosteronan synthase, a bifunctional glycosyltransferase that produces a unique heparosan polysaccharide analog. | glycosaminoglycans [gags] are linear hexosamine-containing polysaccharides. these polysaccharides are synthesized by some pathogenic bacteria to form an extracellular coating or capsule. this strategy forms the basis of molecular camouflage since vertebrates possess naturally-occurring gags that are essential for life. a recent sequence database search identified a putative protein from the opportunistic pathogen comamonas testosteroni that exhibits similarity to the pasteurella multocida glycos ... | 2011 | 21610195 |
| effects of entrapment on nucleic acid content, cell morphology, cell surface property, and stress of pure cultures commonly found in biological wastewater treatment. | the effects of cell entrapment on nucleic acid content, cell morphology, cell surface property, and stress of major groups of bacteria (betaproteobacteria and gammaproteobacteria) in biological municipal wastewater treatment were investigated. three different entrapment media (alginate, carrageenan, and polyvinyl alcohol) were examined. results indicated that the entrapment and type of entrapment media affected nucleic acid content, cell morphology, cell surface property, and stress of the three ... | 2011 | 21660542 |
| recurrent intravascular catheter-related bacteremia caused by delftia acidovorans in a hemodialysis patient. | we report the first case of recurrent intravascular catheter-related bacteremia in a pediatric hemodialysis patient caused by delftia acidovorans, previously called comamonas acidovorans or pseudomonas acidovorans. the patient had a history of multiple infections of central vascular catheters with other organisms, requiring courses of antibiotics and catheter replacements. previously reported cases of d. acidovorans infections are reviewed. in vitro susceptibility testing for cephalosporins is n ... | 2011 | 21775546 |
| effects of microbial species, organic loading and substrate degradation rate on the power generation capability of microbial fuel cells. | four microbial fuel cells (mfcs) inoculated with different bacterial species were constructed. the species were pseudomonas putida, comamonas testosteroni, corynebacterium gultamicum, and arthrobacter polychromogenes. the mfcs were operated under identical continuous flow conditions. the factors affecting the capabilities of the mfcs for treating organic matter and generating power were evaluated and compared. the factors include microbial species type, organic loading, and substrate degradation ... | 2011 | 21750995 |
| enhanced remediation of dioxins-spiked soil by a plant-microbe system using a dibenzofuran-degrading comamonas sp. and trifolium repens l. | in this study, rhizoremediation technology was applied to dioxins-spiked soil. a dibenzofuran-degrading bacterium comamonas sp. strain kd7, reported in the previous paper, was used in combination with white clover (trifolium repens l.). first, the effect of strain kd7 on clover seed germination and root elongation was examined in the presence of dioxins compounds. as a result, the white clover seeds inoculated with strain kd7 exhibited a higher germination efficiency and increased root elongatio ... | 2011 | 21839489 |
| identification of comamonas species using 16s rrna gene sequence. | a bacterial strain bz02 was isolated from a water sample collected from river gomti at the indian city of lucknow. we characterized the strain using 16s rrna sequence. phylogenetic analysis showed that the strain formed a monophyletic clade with members of the genus comamonas. the closest phylogenetic relative was comamonas testosteroni with 95% 16s rrna gene sequence similarity. it is proposed that the identified strain bz02 be assigned as the type strain of a species of the genus comamonas (co ... | 2009 | 19759812 |
| time-resolved selected ion flow tube mass spectrometric quantification of the volatile compounds generated by e. coli jm109 cultured in two different media. | preliminary measurements have been made of the volatile compounds emitted by the bacterium e. coli jm109 cultured in the commonly used media dulbecco's modified eagle's medium (dmem) and lysogeny broth (lb) using selected ion flow tube mass spectrometry, sift-ms, as a step towards the real time, non-invasive monitoring of accidental infections of mammalian cell cultures. in one procedure, the culture medium alone and the e. coli cells/medium combination were held at 37 -¦c in bottles sealed with ... | 2011 | 21710596 |
| comparison of the bacterial community and characterization of plant growth-promoting rhizobacteria from different genotypes of chrysopogon zizanioides (l.) roberty (vetiver) rhizospheres. | molecular approaches [pcr-denaturing gradient gel electrophoresis (dgge)] were used to determine whether three different vetiver (chrysopogon zizanioides) genotypes, commercially used in brazil and considered economically important over the world, select specific bacterial populations to coexist in their rhizospheres. dgge profiles revealed that the predominant rhizospheric bacterial community hardly varies regarding the vetiver genotype. moreover, using traditional cultivation methods, bacteria ... | 2009 | 19763409 |
| isolation of the exoelectrogenic denitrifying bacterium comamonas denitrificans based on dilution to extinction. | the anode biofilm in a microbial fuel cell (mfc) is composed of diverse populations of bacteria, many of whose capacities for electricity generation are unknown. to identify functional populations in these exoelectrogenic communities, a culture-dependent approach based on dilution to extinction was combined with culture-independent community analysis. we analyzed the diversity and dynamics of microbial communities in single-chamber air-cathode mfcs with different anode surfaces using denaturing ... | 2010 | 19779712 |
| genome analysis and characterization of zinc efflux systems of a highly zinc-resistant bacterium, comamonas testosteroni s44. | a novel and multiple metal(loid)-resistant strain comamonas testosteroni s44 with a high zn(2+) resistance level (10-ámm) was isolated. to understand the molecular basis for the high zinc resistance, whole genome sequencing was performed and revealed a large number of genes encoding putative metal(loid) resistance proteins, mobile genetic elements (mges) and horizontal gene transfer (hgt) events that may have occurred to adapt to a metal(loid)-contaminated environment. in particular, 9 putative ... | 2011 | 21704702 |
| homology modeling and docking studies of comamonas testosteroni b-356 biphenyl-2,3-dioxygenase involved in degradation of polychlorinated biphenyls. | biphenyl dioxygenase is a microbial enzyme which catalyzes the stereospecific dioxygenation of aromatic rings of biphenyl congeners leading to their degradation. hence, it has attracted the attention of researchers due to its ability to oxidize chlorinated biphenyls, which are one of the serious environmental contaminants. in the present study, the three-dimensional model of alpha-subunit of biphenyl dioxygenase (bpha) from comamonas testosteroni b-356 has been constructed. the resulting model w ... | 2010 | 19879892 |
| influence of microbial interactions and eps/polysaccharide composition on nutrient removal activity in biofilms formed by strains found in wastewater treatment systems. | the study of biofilm function, structure and microbial interactions might help to improve our understanding of biofilm wastewater treatment processes. however, few reports specifically address the influence of interactions within multispecies biofilms on microbial activity and biofilm composition. thus, the relationship between biofilm formation, denitrification activity, phosphorus removal and the composition of extracellular polymeric substances (eps), exopolysaccharides and the bacterial comm ... | 2010 | 20869860 |
| ralstonia sp. u2 naphthalene dioxygenase and comamonas sp. js765 nitrobenzene dioxygenase show differences in activity towards methylated naphthalenes. | methylsubstituted naphthalenes constitute a significant part of light gas oil fractions (lgo). these are toxic compounds with low fuel value, and can potentially be enzymatically modified to increase the fuel value and at the same time reduce toxicity. the first step in the biodegradation of naphthalene involves dioxygenation of the aromatic ring catalysed by naphthalene dioxygenase (ndo). here we show that recombinantly produced ndo from ralstonia sp. u2 and the related nitrobenzene dioxygenase ... | 2011 | 22036075 |
| in vitro studies on degradation of synthetic dye mixture by comamonas sp. vs-mh2 and evaluation of its efficacy using simulated microcosm. | reactive azo dyes are considered as one of the most detrimental pollutants from industrial effluents and therefore their biodegradation is receiving constant scientific consideration. a bacterial isolate vs-mh2, originating from dye contaminated sites of gujarat, india, was exploited for its ability to degrade a synthetic dye mixture (sdm) (comprising of four azo reactive dyes) under static conditions. the identification of the isolate by 16s rrna gene sequencing revealed it to be comamonas sp. ... | 2011 | 21996479 |
| hydroxysteroid dehydrogenase transformations of 5β-scymnol and identification of oxoscymnol transformation products by liquid chromatography-tandem mass spectroscopy. | a new and sensitive high performance liquid chromatography (hplc) separation procedure coupled with tandem mass spectroscopy (ms and ms(2)) detection was developed to identify for the first time the oxidation products of 5β-scymnol [(24r)-(+)-5β-cholestan-3α,7α,12α,24,26,27-hexol] catalysed by bacterial hydroxysteroid dehydrogenase (hsd) reactions in vitro. the authentic scymnol (mw 468) standard yielded a protonated molecular ion [m+h](+) at m/z 469 da, and higher mass adduct ions attributed to ... | 2010 | 20974163 |
| indigo biosynthesis by comamonas sp. mq. | an indigo-producing strain was isolated from activated sludge and identified as comamonas sp. based on 16s rrna analysis. it produced indigo at 26.5 mg/l with a conversion of indole to indigo of 47%. indole at 50 mg/l plus 200 mg naphthalene/l gave 32.2 mg indigo/l with a 58% conversion. a pathway for indigo formation is proposed. this is the first study of indigo biosynthesis by comamonas sp. | 2011 | 22038546 |
| Identification and Characterization of the LysR-type Transcriptional Regulator HsdR for Steroid-inducible Expression of the 3a-Hydroxysteroid Dehydrogenase/Carbonyl Reductase Gene in Comamonas testosteroni. | 3a-hydroxysteroid dehydrogenase/carbonyl reductase (3a-HSD/CR) from Comamonas testosteroni (C. testosteroni) is a key enzyme in steroid degradation in soil and water. 3a-HSD/CR gene (hsdA) expression can be induced by steroids like testosterone and progesterone. Previously, we have shown that induction of hsdA expression by steroids is a derepression where steroidal inducers bind to two repressors, RepA and RepB, thereby preventing blocking of hsdA transcription and translation, respectively. In ... | 2011 | 22156416 |
| diagnosis and quantification of glycerol assimilating denitrifying bacteria in an integrated fixed-film activated sludge reactor via 13c dna stable-isotope probing. | glycerol, a byproduct of biodiesel and oleo-chemical manufacturing operations, represents an attractive alternate to methanol as a carbon and electron donor for enhanced denitrification. however, unlike methanol, little is known about the diversity and activity of glycerol assimilating bacteria in activated sludge. in this study, the microbial ecology of glycerol assimilating denitrifying bacteria in a sequencing batch integrated fixed film activated sludge (sb-ifas) reactor was investigated usi ... | 2010 | 21053955 |
| steroid degradation in comamonas testosteroni. | steroid degradation by comamonas testosteroni and nocardia restrictus have been intensively studied for the purpose of obtaining materials for steroid drug synthesis. c. testosteroni degrades side chains and converts single/double bonds of certain steroid compounds to produce androsta-1,4-diene 3,17-dione or the derivative. following 9α-hydroxylation leads to aromatization of the a-ring accompanied by cleavage of the b-ring, and aromatized a-ring is hydroxylated at c-4 position, cleaved at δ4 by ... | 2010 | 21056662 |
| [immobilized ammonia-oxidizing bacteria comamonas aquatic lnl3 and its partial nitrification characterization]. | a new kind of ammonia-oxidizing bacteria (aob)-comamonas aquatic lnl3 was screened out and immobilized by poly (hea)-poly (hema) copolymer carrier using irradiation techniques. four kinds of impact factors on short-cut nitrification, including temperature, ph, do and free ammonia (fa) concentration had been investigated. the result showed that aob-comamonas aquatic lnl3 had short-cut nitrification capability and the optimal temperature, ph, do and fa concentration were 30 degrees c, 8.5, 4.03 mg ... | 2009 | 19968113 |
| structural studies on the full-length lysr-type regulator tsar from comamonas testosteroni t-2 reveal a novel open conformation of the tetrameric lttr fold. | lysr-type transcriptional regulators (lttrs) constitute the largest family of regulators in prokaryotes. the full-length structures of the lttr tsar from comamonas testosteroni t-2 and its complex with the natural inducer para-toluensulfonate have been characterized by x-ray diffraction. both ligand-free and complexed forms reveal a dramatically different quaternary structure from that of cbnr from ralstonia eutropha, or a putative lysr-type regulator from pseudomonas aeruginosa, the only other ... | 2010 | 20059681 |
| polyphasic bacterial community analysis of an aerobic activated sludge removing phenols and thiocyanate from coke plant effluent. | biological purification processes are effective tools in the treatment of hazardous wastes such as toxic compounds produced in coal coking. in this study, the microbial community of a lab-scale activated sludge system treating coking effluent was assessed by cultivation-based (strain isolation and identification, biodegradation tests) and culture-independent techniques (sequence-aided t-rflp, taxon-specific pcr). the results of the applied polyphasic approach showed a simple microbial community ... | 2010 | 20093025 |
| cloning, expression and functional analysis of nicotinate dehydrogenase gene cluster from comamonas testosteroni ja1 that can hydroxylate 3-cyanopyridine. | a nicotinate dehydrogenase (nadh) gene cluster was cloned from comamonas testosteroni ja1. the enzyme, termed nadh(ja1), is composed of 21, 82, and 46 kda subunits, respectivley containing [2fe2s], mo(v) and cytochrome c domains. the recombinant nadh(ja1) can catalyze the hydroxylation of nicotinate and 3-cyanopyridine. nadh(ja1) protein exhibits 52.8% identity to the amino acid sequence of nadh(kt2440) from p. putida kt2440. sequence alignment analysis showed that the [2fe2s] domain in nadh(ja1 ... | 2010 | 20119845 |
| characterization of comamonas thiooxidans sp. nov., and comparison of thiosulfate oxidation with comamonas testosteroni and comamonas composti. | comamonas thiooxidans (strain s23(t)) capable of oxidizing thiosulfate under a mixotrophic growth condition was isolated from a sulfur spring. dna-dna homology study showed 55% similarity with comamonas testosteroni kctc2990(t) and 52% with comamonas composti lmg24008(t), the nearest phylogenetic relative (16s rrna sequence similarity <97%). comparative genomic fingerprinting by using eric and rep-pcr further delineated species identity of the strain s23(t) for which comamonas thiooxidans sp. no ... | 2010 | 20148250 |
| cloning, expression and characterization of a novel short-chain dehydrogenase/reductase (sdrx) in comamonas testosteroni. | the short-chain dehydrogenase/reductase (sdr) superfamily is a large and diverse group of genes with members found in all forms of life. comamonas testosteroni atcc11996 is a gram-negative bacterium which can use steroids as carbon and energy source. in previous investigations, we have identified 3α-hydroxysteroid dehydrogenase/carbonyl reductase (3α-hsd/cr) from c. testosteroni as a member of the sdr superfamily that catalyzes the reversible interconversion of hydroxyl and oxo groups at positio ... | 2010 | 21111045 |
| characterization of the steroid degrading bacterium s19-1 from the baltic sea at kiel, germany. | steroid contamination of sea water is an ever growing problem and impacts population dynamics of all kinds of sea animals. we have long experience with the soil bacterium comamonas testosteroni atcc11996 which is able to catabolize a variety of steroids and polycyclic aromatic hydrocarbons, and which might be used in the bioremediation of contaminated places. in c. testosteroni about 20 enzymes which are involved in steroid degradation could be induced by 0.5mm testosterone. in this work, we iso ... | 2010 | 21185812 |
| identification of a thiolase gene essential for ß-oxidation of the acyl side chain of the steroid compound cholate in pseudomonas sp. strain chol1. | bile salts such as cholate are steroid compounds occurring ubiquitously in the environment through excretion by animals. cholate degradation by pseudomonas sp. strain chol1 is initiated by a-ring oxidation and ß-oxidation of the acyl side chain. a transposon mutant of strain chol1 was isolated that could not grow with cholate, but transformed it into several steroid compounds accumulating in culture supernatants. the main product was identified as (22e)-7a,12a-dihydroxy-3-oxochola-1,4,22-triene- ... | 2011 | 21362022 |
| biofilms formed on humic substances: response to flow conditions and carbon concentrations. | stream biofilms are exposed to dynamic conditions of flow velocity and organic carbon availability. thus, the aim of this study was to investigate the response of biofilms formed with and without humic substances (hss) to an increase in flow velocity (0.04-0.10 ms(-1)) and hss concentration (9.7+/-1.0 to 19.8+/-0.4 mgl(-1) c). the highest amount of biofilm, measured as volatile suspended solids and total countable cells, was observed at 0.10 m s(-1) without hss. the bacterial community compositi ... | 2010 | 20413305 |
| initial steps in anoxic testosterone degradation by steroidobacter denitrificans. | steroid compounds have many important physiological activities in higher organisms. testosterone and related steroids are important environmental contaminants that disrupt the endocrine systems of animals. the degradation of steroids, especially under anoxic conditions, is challenging because of their complex chemical structure. a denitrifying gamma-proteobacterium, steroidobacter denitrificans, able to grow anaerobically on a variety of steroids as the sole carbon and energy source was adopted ... | 2010 | 20413554 |
| flow cytometry-based method for isolating live bacteria with meta-cleavage activity on dihydroxy compounds of biphenyl. | a new method for isolating targeted live bacterial cells was established with the use of cell sorting by flow cytometry (fcm) based on the fluorescence of the intermediate metabolite of biphenyl degradation. during biphenyl degradation, a pcb degrader, comamonas testosteroni tk102, produces a meta-cleavage intermediate metabolite, 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid (hopda), which emits green fluorescence. hopda was produced from 2,3-dihydroxy biphenyl as a substrate, but it was not ap ... | 2010 | 20471608 |
| elucidating mtbe degradation in a mixed consortium using a multidisciplinary approach. | the structure and function of a microbial community capable of biodegrading methyl-tert-butyl ether (mtbe) was characterized using compound-specific stable isotope analysis (csia), clone libraries and stable isotope probing of proteins (protein-sip). the enrichment culture (us3-m), which originated from a gasoline-impacted site in the united states, has been enriched on mtbe as the sole carbon source. the slope of isotopic enrichment factors (epsilon(c) of -2.29+/-0.03 per thousand; epsilon(h) o ... | 2010 | 20491917 |
| steroid degradation genes in comamonas testosteroni ta441: isolation of genes encoding a δ4(5)-isomerase and 3α- and 3β-dehydrogenases and evidence for a 100 kb steroid degradation gene hot spot. | in previous studies, we identified two major comamonas testosteroni ta441 gene clusters involved in steroid degradation. because most of the genes included in these clusters were revealed to be involved in degradation of basic steroidal structures and a few were suggested to be involved in the degradation of modified steroid compounds, we investigated the spectrum of steroid compounds degradable for ta441 to better identify the genes involved in steroid degradation. ta441 degraded testosterone, ... | 2010 | 20554032 |
| bacterial community structure of a full-scale biofilter treating pig house exhaust air. | biological air filters represent a promising tool for treating emissions of ammonia and odor from pig facilities. quantitative fluorescence in situ hybridization (fish) and 16s rrna gene sequencing were used to investigate the bacterial community structure and diversity in a full-scale biofilter consisting of two consecutive compartments (front and back filter). the analysis revealed a highly specialized bacterial community of limited diversity, dominated by a few groups of betaproteobacteria (e ... | 2011 | 21514081 |
| microbial fuel cells operating on mixed fatty acids. | strategies are being developed to harvest the energy content of the wasted sludge generated from the treatment of domestic wastewater. sludge can be hydrolysed and fermented, giving a mixture of volatile fatty acids (vfas). based on the composition of such a fermented stream, synthetic media were created and tested for vfa conversion in microbial fuel cells (mfcs). mainly acetate and propionate were preferred as electron donors in the mixed vfa system, which generated a power density of 49+/-1 m ... | 2010 | 19854639 |
| the comamonas testosteroni steroid biosensor system (coss)--reflection on other methods. | natural and synthetic steroid hormones are released uncontrolled into the environment and are considered as pollutants with regard to their endocrine activity and negative influence on all kind of organisms. due to their widespread presence, endocrine activity even at low concentrations, and their potential adverse effects in both the environment and human health, there is an increasing need for the development of rapid, sensitive and quantitative techniques for measuring trace levels of these s ... | 2010 | 20558289 |
| Isolation of bacteria capable of growth with 2-methylisoborneol and geosmin as the sole carbon and energy sources. | Using a relatively simple enrichment technique, geosmin and 2-methylisoborneol (MIB)-biodegrading bacteria were isolated from a digestion basin in an aquaculture unit. Comparison of 16S rRNA gene sequences affiliated one of the three isolates with the Gram-positive genus Rhodococcus, while the other two isolates were found to be closely related to the Gram-negative family Comamonadaceae (Variovorax and Comamonas). Growth rates and geosmin and MIB removal rates by the isolates were determined und ... | 2012 | 22081577 |
| a novel testosterone catabolic pathway in bacteria. | forty years ago, coulter and talalay (a. w. coulter and p. talalay, j. biol. chem. 243:3238-3247, 1968) established the oxygenase-dependent pathway for the degradation of testosterone by aerobes. the oxic testosterone catabolic pathway involves several oxygen-dependent reactions and is not available for anaerobes. since then, a variety of anaerobic bacteria have been described for the ability to degrade testosterone in the absence of oxygen. here, a novel, oxygenase-independent testosterone cata ... | 2011 | 21725000 |
| testosterone-mineralizing culture enriched from swine manure: characterization of degradation pathways and microbial community composition. | environmental releases and fate of steroid sex hormones from livestock and wastewater treatment plants are of increasing regulatory concern. despite the detection of these hormones in manures, biosolids, and the environment, little attention has been paid to characterization of fecal bacteria capable of hormone degradation. the enrichments of (swine) manure-borne bacteria capable of aerobic testosterone degradation were prepared and the testosterone mineralization pathway was elucidated. six dna ... | 2011 | 21740029 |
| arsenic-resistant bacteria solubilized arsenic in the growth media and increased growth of arsenic hyperaccumulator pteris vittata l. | the role of arsenic-resistant bacteria (arb) in arsenic solubilization from growth media and growth enhancement of arsenic-hyperaccumulator pteris vittata l. was examined. seven arb (tolerant to 10mm arsenate) were isolated from the p. vittata rhizosphere and identified by 16s rrna sequencing as pseudomonas sp., comamonas sp. and stenotrophomonas sp. during 7-d hydroponic experiments, these bacteria effectively solubilized arsenic from the growth media spiked with insoluble feaso(4) and alaso(4) ... | 2011 | 21840210 |
| Remediation of oil-based drill cuttings through a biosurfactant-based washing followed by a biodegradation treatment. | In this study, oil-based drill cuttings were washed by a rhamnolipid solution and then subjected to bioremediation in stainless steel boxes using sawdust as bulking agent. A mixed bacterial culture, mainly containing Pseudomonas, Acinetobacter, Alcaligenes, Agrobacterium, and Comamonas, was used as inoculums. Approximately 83% of organics were removed after washing under optimal conditions (liquid/solid ratio, 3:1; washing time, 20 min; stirring speed, 200 rpm; rhamnolipid concentration, 360 mg/ ... | 2011 | 21925873 |
| assessment of denitrifying bacterial composition in activated sludge. | the abundance and structure of denitrifying bacterial community in different activated sludge samples were assessed, where the abundance of denitrifying functional genes showed nirs in the range of 10(4)-10(5), nosz with 10(4)-10(6) and 16s rrna gene in the range 10(9)-10(10) copy number per ml of sludge. the culturable approach revealed pseudomonas sp. and alcaligenes sp. to be numerically high, whereas culture independent method showed betaproteobacteria to dominate the sludge samples. comamon ... | 2011 | 21868215 |