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microbiological influences in 'blue water' copper corrosion.to investigate the influence of micro-organisms associated with copper corrosion on 'blue water' corrosion in drinking water.200415281940
a 19f nmr study of fluorobenzoate biodegradation by sphingomonas sp. hb-1.while several microorganisms readily degrade 2- and 4-fluorobenzoates, only a very small number appear to catabolise the 3-fluoro isomer, owing to the accumulation of toxic intermediates. here we describe the isolation of a bacterium capable of using 3-fluorobenzoate as a sole source of carbon and energy, and the experiments conducted to define the steps involved in the biodegradation of this compound. the organism was identified as a strain belonging to the genus sphingomonas by sequence analys ...200415321683
comparison of n-eicosane and phenanthrene removal by pure and mixed cultures of two marine bacteria.the biotransformation activities of two hydrocarbonoclastic marine bacteria, corynebacterium sp. and sphingomonas sp. 2mpii, on n-eicosane and phenanthrene were investigated. during a 56-day experiment, in pure and mixed cultures, corynebacterium sp. and sphingomonas sp. 2mpii removed about 70% of the initial n-eicosane and phenanthrene concentrations (1 and 0.4 g l(-1), respectively). in pure cultures, culturable cell abundances increased over time, from 0.8 to 8.6 x 10(-11) cfu l(-1) (coryneba ...200415325883
molecular identification and characterization of an alginate-binding protein on the cell surface of sphingomonas sp. a1.cells of sphingomonas sp. a1 (strain a1) directly incorporate a macromolecule, alginate, into cytoplasm through a biosystem, or "super-channel," consisting of a pit on the cell surface, alginate-binding proteins in periplasm, and an abc transporter in the inner membrane. the pit functions as a concentrator for extracellular alginate. through differential display analysis, a protein (p8) with a molecular mass of 20kda and a pi of 7.4 was found to be inducibly expressed in the outer membrane of al ...200415336522
regulation of tetralin biodegradation and identification of genes essential for expression of thn operons.the tetralin biodegradation genes of sphingomonas macrogolitabida strain tfa are clustered in two closely linked and divergent operons. to analyze expression of both operons under different growth conditions, transcriptional and translational gene fusions of the first genes of each operon to lacz have been constructed in plasmids unable to replicate in sphingomonas and integrated by recombination into the genome of strain tfa. expression analysis indicated that the transcription of both genes is ...200415342579
requirement of a relatively high threshold level of mg(2+) for cell growth of a rhizoplane bacterium, sphingomonas yanoikuyae ec-s001.mg(2+) is one of the essential elements for bacterial cell growth. the presence of the magnesium cation (mg(2+)) in various concentrations often affects cell growth restoration in plant-associating bacteria. this study attempted to determine whether mg(2+) levels in sphingomonas yanoikuyae ec-s001 affected cell growth restoration in the host plant and what the threshold level is. s. yanoikuyae ec-s001, isolated from the rhizoplane of spinach seedlings grown from surface-sterilized seeds under as ...200415345402
genetic and phenotypic diversity of (r/s)-mecoprop [2-(2-methyl-4-chlorophenoxy)propionic acid]-degrading bacteria isolated from soils.twelve mecoprop-degrading bacteria were isolated from soil samples, and their genetic and phenotypic characteristics were investigated. analysis of 16s rdna sequences indicated that the isolates were related to members of the genus sphingomonas. ten different chromosomal dna patterns were obtained by polymerase-chain-reaction (pcr) amplification of repetitive extragenic palindromic (rep) sequences from the 12 isolates. the isolates were found to be able to utilize the chiral herbicide mecoprop a ...200415357300
isolation and characterization of genes encoding polycyclic aromatic hydrocarbon dioxygenase from acenaphthene and acenaphthylene degrading sphingomonas sp. strain a4.sphingomonas sp. strain a4 is capable of utilizing acenaphthene and acenaphthylene as sole carbon and energy sources, but it is unable to grow on other polycyclic aromatic hydrocarbons (pahs). the genes encoding terminal oxygenase components of ring-hydroxylating dioxygenase (arha1 and arha2) were isolated from this strain by means of the ability to oxidize indole to indigo of the escherichia coli clone containing electron transport proteins from phenanthrene-degrading sphingobium sp. strain p2. ...200415358414
a sphingomonas bacterium interacting with epithelial cells.bacteria of the genus sphingomonas are environmental organisms that have recently been implicated in a variety of community-acquired and nosocomial infections. during studies on bacteria-cell interactions, we incurred a microorganism contaminating our hela cell culture, possibly from water utilized for reagent preparation; this bacterium appeared to tightly adhere to cell monolayers and to survive, with only limited growth rate, which did not seem to alter cells as far as shape, growth rate or s ...200415380551
degradation of aromatic hydrocarbons by sphingomonas paucimobilis strain epa505.to determine the substrate range capability of sphingomonas paucimobilis strain epa505, a number of aromatic compounds were tested as potential growth substrates. strain epa505 grew on phenanthrene, naphthalene, fluoranthene, toluene, benzoic acid, 2,3- and 3,4-dihydroxybenzoic acids, 1-chloro-2,4-dinitrobenzene, anthracene, 2-hydroxy-3-naphthoic acid and 1-hydroxy- 2-naphthoic acid, salicylic acid, and catechol. strain epa505 was unable to grow on coumarine 3-carboxylic acid, naphthalene dicarb ...200415386141
green fluorescent protein as a marker for monitoring a pentachlorophenol degrader sphingomonas chlorophenolica atcc39723.sphingomonas chlorophenolica atcc39723 was successfully labeled with the gfp (green fluorescent protein) gene inserted into the pcpb gene by homologous recombination. as the gfp recombinant was easily distinguished from other indigenous organisms, the population of gfp recombinant was monitored after being released into the soil microcosms. their population density dropped from 10(8) to 10(6) (cfu/ml) in the non-sterilized soil microcosms during the first 6 days. moreover, the gfp recombinant wa ...200415459656
electrokinetic transport of pah-degrading bacteria in model aquifers and soil.an investigation of the mobility, viability, and activity of polycyclic aromatic hydrocarbon (pah) degrading bacteria in an electric field is presented. bench-scale model aquifers were used to test electrophoresis and electroosmosis as potential mechanisms for bacterial dispersion in contaminated sites. glass beads, alluvial sand from lake geneva, and historically polluted clayey soil were used as packing materials. the green-fluorescent protein labeled pah-degrading bacteria sphingomonas sp. l1 ...200415461168
thermophilic, reversible gamma-resorcylate decarboxylase from rhizobium sp. strain mtp-10005: purification, molecular characterization, and expression.we found the occurrence of thermophilic reversible gamma-resorcylate decarboxylase (gamma-rdc) in the cell extract of a bacterium isolated from natural water, rhizobium sp. strain mtp-10005, and purified the enzyme to homogeneity. the molecular mass of the enzyme was determined to be about 151 kda by gel filtration, and that of the subunit was 37.5 kda by sodium dodecyl sulfate-polyacrylamide gel electrophoresis; in other words, the enzyme was a homotetramer. the enzyme was induced specifically ...200415466039
genetic analysis of phenoxyalkanoic acid degradation in sphingomonas herbicidovorans mh.phenoxyalkanoic acid degradation is well studied in beta- and gammaproteobacteria, but the genetic background has not been elucidated so far in alphaproteobacteria. we report the isolation of several genes involved in dichlor- and mecoprop degradation from the alphaproteobacterium sphingomonas herbicidovorans mh and propose that the degradation proceeds analogously to that previously reported for 2,4-dichlorophenoxyacetic acid (2,4-d). two genes for alpha-ketoglutarate-dependent dioxygenases, sd ...200415466552
enzymatic hydrolysis of alpha- and beta-oligo(l-aspartic acid)s by poly(aspartic acid) hydrolases-1 and 2 from sphingomonas sp. kt-1.the enzymatic hydrolysis of alpha- and beta-oligo(l-aspartic acid)s by paa hydrolase-1 and paa hydrolase-2 (purified from sphingomonas sp. kt-1) was performed to elucidate the mechanism of the microbial degradation by sphingomonas sp. kt-1 of the thermally synthesized alpha,beta-poly(d,l-aspartic acid) (tpaa). gpc analysis of the hydrolyzed products of alpha- and beta-tetra(l-aspartic acid)s by paa hydrolase-1 has showed that paa hydrolase-1 is capable of hydrolyzing only the specific amide bond ...200415468224
reversible and nonoxidative gamma-resorcylic acid decarboxylase: characterization and gene cloning of a novel enzyme catalyzing carboxylation of resorcinol, 1,3-dihydroxybenzene, from rhizobium radiobacter.we found a gamma-resorcylic acid (gamma-ra, 2,6-dihydroxybenzoic acid) decarboxylase, as a novel enzyme applicable to carboxylation of resorcinol (re, 1,3-dihydroxybenzene) to form gamma-ra, in a bacterial strain rhizobium radiobacter wu-0108 isolated through the screening of gamma-ra degrading microorganisms. the activities for carboxylation of re and decarboxylation of gamma-ra were detected in the cell-free extracts of r. radiobacter wu-0108 grown aerobically with gamma-ra. the enzyme, gamma- ...200415474471
streptomycin as a selective agent to facilitate recovery and isolation of introduced and indigenous sphingomonas from environmental samples.sphingomonas is an organism of major interest for the degradation of organic contaminants in soils and other environments. a medium based on the aminoglycoside antibiotic streptomycin (sm) was developed, which, together with the yellow pigmentation of sphingomonas, facilitated the detection, recovery and quantification of culturable sphingomonas from soils. all 29 previously described bacterial strains belonging to 17 different sphingomonas species were able to grow on mineral media containing 2 ...200415479246
characterization and phylogenetic analysis of a phenanthrene-degrading strain isolated from oil-contaminated soil.bacterium strain eva17 was isolated from an oil-contaminated soil, and identified as sphingomonas sp. based on analysis of 16s rdna sequence, cellular fatty acid composition and physiological-chemical tests. the salicylate hydroxylase and catechol 2, 3-dioxygenase (c230) were detected in cell-free lysates, suggesting a pathway for phenanthrene catabolism via salicylate and catechol. alignment showed that both of the c230 and gst genes of the strain eva17 had high similarity with homologues of st ...200415495962
microbial degradation of a single branched isomer of nonylphenol by sphingomonas ttnp3.the endocrine disrupting chemical nonylphenol (np) is a technical product which consists of a complex mixture of nonylphenols with different alkyl side-chain isomers. since the bio-degradation of each np isomer may lead to its own range of metabolites, the isolation and identification of transformation products is very difficult. in order to overcome this difficulty, the nonylphenol isomer 4(3',5'-dimethyl-3'-heptyl)-phenol (p353np) was synthesized, and its degradation by an axenic culture of sp ...200415497847
bioavailability of a nonylphenol isomer in dependence on the association to dissolved humic substances.humic substances are important environmental components since they represent a very large part of organic compounds on earth. according to many reports, dissolved humic substances are a determinant parameter for the bioavailability of xenobiotic compounds. for the present bioavailability studies, two kinds of dissolved humic substances, a commercially available humic acid and fulvic acids isolated from peat were used. as the relevant xenobiotic, a defined branched nonylphenol isomer, 4(3',5'-dim ...200415497858
dynamics of multiple lin gene expression in sphingomonas paucimobilis b90a in response to different hexachlorocyclohexane isomers.sphingomonas paucimobilis b90a is able to degrade the alpha-, beta-, gamma-, and delta-isomers of hexachlorocyclohexane (hch). it contains the genes lina, linb, linc, lind, line, and linr, which have been implicated in hch degradation. in this study, dynamic expression of the lin genes was measured in chemostat-grown s. paucimobilis b90a by rna dot blot hybridization and real-time reverse transcriptase pcr upon exposure to a pulse of different hch isomers. irrespective of the addition of hch, li ...200415528530
identification and functional analysis of two aromatic-ring-hydroxylating dioxygenases from a sphingomonas strain that degrades various polycyclic aromatic hydrocarbons.in this study, the enzymes involved in polycyclic aromatic hydrocarbon (pah) degradation in the chrysene-degrading organism sphingomonas sp. strain chy-1 were investigated. [14c]chrysene mineralization experiments showed that pah-grown bacteria produced high levels of chrysene-catabolic activity. one pah-induced protein displayed similarity with a ring-hydroxylating dioxygenase beta subunit, and a second pah-induced protein displayed similarity with an extradiol dioxygenase. the genes encoding t ...200415528538
degradation of a nonylphenol single isomer by sphingomonas sp. strain ttnp3 leads to a hydroxylation-induced migration product.sphingomonas sp. strain ttnp3 degrades 4(3',5'-dimethyl-3'-heptyl)-phenol and unidentified metabolites that were described previously. the chromatographic analyses of the synthesized reference compound and the metabolites led to their identification as 2(3',5'-dimethyl-3'-heptyl)-1,4-benzenediol. this finding indicates that the nonylphenol metabolism of this bacterium involves unconventional degradation pathways where an nih shift mechanism occurs.200415528560
sphingomonas phyllosphaerae sp. nov., from the phyllosphere of acacia caven in argentina.two bacterial strains (fa1 and fa2(t)) were isolated from the phyllosphere of a leguminous tree, acacia caven, in central argentina. the strains were gram-negative, strictly aerobic, rod-shaped, motile and formed yellow-pigmented colonies on nutrient agar. the two-primer rapd patterns of the two strains were identical, suggesting that they belong to the same species. the complete 16s rrna gene sequences of the two strains were obtained and comparisons demonstrated that they cluster phylogenetica ...200415545449
sphingomonas oligophenolica sp. nov., a halo- and organo-sensitive oligotrophic bacterium from paddy soil that degrades phenolic acids at low concentrations.the taxonomic position of a halo- and organo-sensitive, oligotrophic soil bacterium, strain s213(t), was investigated. cells were gram-negative, non-motile, strictly aerobic, yellow-pigmented rods of short to medium length on diluted nutrient broth. when 0.1-0.4 % (w/v) nacl was added to diluted media composed of peptone and meat extract, growth was inhibited with increasing nacl concentration and the cells became long aberrant forms. when 6 mm cacl(2) was added, the cells grew quite normally an ...200415545456
plant-assisted degradation of phenanthrene as assessed by solid-phase microextraction (spme).the soil bacterium sphingomonas yanoikuyae was isolated from a petroleum-contaminated soil and grown on mineral salts agar overlaid with the polycyclic aromatic hydrocarbon phenanthrene. the effect of white mustard, sinapis alba, on phenanthrene degradation by s. yanoikuyae in artificially contaminated redi-earth-sand was examined. solid-phase-microextraction (spme) gas chromatography-flame ionization detection (gc-fid) was used to quantify the concentration of phenanthrene in the gas phase of m ...200415554477
bacterial diversity of a soil sample from schirmacher oasis, antarctica.the bacterial diversity of a soil sample collected in the vicinity of lake zub, schirmacher oasis, antarctica, was determined both by establishing pure colonies of culturable bacteria and by cloning the total 16s rdna of the soil and establishing the phylogeny of the clones. analysis of the 16s rrna gene clones indicated that the bacteria belonged to the classes alpha-proteobacteria, beta-proteobacteria, gamma-proteobacteria, gemmatimonas, bacteriodetes, actinobacteria, chloroflexi and chlamydia ...200415559969
a previously unexposed forest soil microbial community degrades high levels of the pollutant 2,4,6-trichlorophenol.2,4,6-trichlorophenol (2,4,6-tcp) is a hazardous pollutant that is efficiently degraded by some aerobic soil bacterial isolates under laboratory conditions. the degradation of this pollutant in soils and its effect on the soil microbial community are poorly understood. we report here the ability of a previously unexposed forest soil microbiota to degrade high levels of 2,4,6-tcp and describe the changes in the soil microbial community found by terminal restriction fragment length polymorphism (t ...200415574963
isolation and characterization of a novel sphingomonad capable of growth with chrysene as sole carbon and energy source.a bacterial strain able to grow in pure culture with chrysene as sole added carbon and energy source was isolated from pah-contaminated soil after successive enrichment cultures in a biphasic growth medium. initially, growth occurred in the form of a biofilm at the interface between the aqueous and non-aqueous liquid phases. however, after a certain time, a transition occurred in the enrichment cultures, with growth occurring in suspension and a concomitant increase in the rate of chrysene degra ...200415598525
rapid screening and dereplication of bacterial isolates from marine sponges of the sula ridge by intact-cell-maldi-tof mass spectrometry (icm-ms).rapid grouping of bacterial isolates is critical in comprehensive microbial studies of environmental samples or screening programmes e.g. in unknown marine environments where large numbers of strains have to be isolated on different growth media. sets of bacteria have been cultured from the marine sponges isops phlegraei, haliclona sp. 1, phakellia ventilabrum and plakortis sp. growing at a depth of about 300 m on the sula ridge close to the norwegian coast. we employed intact-cell maldi-tof (ic ...200415614563
aerobic degradation of polychlorinated biphenyls.the microbial degradation of polychlorinated biphenyls (pcbs) has been extensively studied in recent years. the genetic organization of biphenyl catabolic genes has been elucidated in various groups of microorganisms, their structures have been analyzed with respect to their evolutionary relationships, and new information on mobile elements has become available. key enzymes, specifically biphenyl 2,3-dioxygenases, have been intensively characterized, structure/sequence relationships have been de ...200415614564
stable long-term indigo production by overexpression of dioxygenase genes using a chromosomal integrated cascade expression circuit.in our laboratory we have analyzed different factors to maximize the yield in heterologous protein expression for long-term cultivation, by combination of an efficient cascade expression system and stable integration in the bacterial chromosome. in this work, we have explored this system for the production of indigo dye as a model for biotechnological production, by expressing in escherichia coli the thna1a2a3a4 genes from sphingomonas macrogolitabida strain tfa, which encode the components of a ...200415664075
two unusual chlorocatechol catabolic gene clusters in sphingomonas sp. tfd44.the genes responsible for the degradation of 2,4-dichlorophenoxyacetate (2,4-d) by alpha-proteobacteria have previously been difficult to detect by using gene probes or polymerase chain reaction (pcr) primers. pcr products of the chlorocatechol 1,2-dioxygenase gene, tfdc, now allowed cloning of two chlorocatechol gene clusters from the sphingomonas sp. strain tfd44. sequence characterization showed that the first cluster, tfdd,rfce, comprises all the genes necessary for the conversion of 3,5-dic ...200415688254
biodegradation of phthalate esters by two bacteria strains.in this study two aerobic phthalic acid ester (pae) degrading bacteria strains, dk4 and o18, were isolated from river sediment and petrochemical sludge, respectively. the two strains were found to rapidly degrade pae with shorter alkyl-chains such diethyl phthalate (dep), dipropyl phthalate (dprp), di-n-butyl phthalate (dbp), benzylbutyl phthalate (bbp) and diphenyl phthalate (dpp) are very easily biodegraded, while pae with longer alkyl-chains such as dicyclohexyl phthalate (dcp) and dihexyl ph ...200415006506
[investigation of the bacteria in the seawater of xisha in the south china sea and their antibiotic sensitivity profile].to investigate the distribution and antibiotic sensitivity of the bacteria in the seawater of xisha in the south china sea.200415041561
hydrocarbon spills on antarctic soils: effects and management.antarctic exploration and research have led to some significant although localized impacts on the environment. human impacts occur around current or past scientific research stations, typically located on ice-free areas that are predominantly soils. fuel spills, the most common occurrence, have the potential to cause the greatest environmental impact in the antarctic through accumulation of aliphatic and aromatic compounds. effective management of hydrocarbon spills is dependent on understanding ...200415046325
isolation of a beta-carotene over-producing soil bacterium, sphingomonas sp.a carotenoid-accumulating bacterium isolated from soil, identified as a sphingomonas sp., grew at 0.18 h(-1) and produced 1.7 mg carotenoids g(-1) dry cell, among which beta-carotene (29% of total carotenoids) and nostoxanthin (36%). a mutant strain, obtained by treatment with ethyl methanesulfonate, accumulated up to 3.5 mg carotenoids g(-1) dry cell. accumulation of beta-carotene by this strain depended on the oxygenation of the growth medium, with maximal accumulation (89%) occurring under li ...200415049373
distribution of nevskia ramosa and other rosette-forming neustonic bacteria.samples from 27 natural and artificial aquatic environments were analyzed for the presence of rosette-forming bacteria by a combined cultivation and molecular biological approach. rosette-forming bacteria developed in 20 enrichment cultures with ammonia-free medium under air. three morphotypes could be distinguished. the most abundant type i resembled nevskia ramosa and formed hydrophobic, flat, and dichotomously branching rosettes. type ii rosettes were three-dimensional and were observed in 10 ...200415054677
organization of lin genes and is6100 among different strains of hexachlorocyclohexane-degrading sphingomonas paucimobilis: evidence for horizontal gene transfer.the organization of lin genes and is6100 was studied in three strains of sphingomonas paucimobilis (b90a, sp+, and ut26) which degraded hexachlorocyclohexane (hch) isomers but which had been isolated at different geographical locations. dna-dna hybridization data revealed that most of the lin genes in these strains were associated with is6100, an insertion sequence classified in the is6 family and initially found in mycobacterium fortuitum. eleven, six, and five copies of is6100 were detected in ...200415060023
occurrence and phylogenetic diversity of sphingomonas strains in soils contaminated with polycyclic aromatic hydrocarbons.bacterial strains of the genus sphingomonas are often isolated from contaminated soils for their ability to use polycyclic aromatic hydrocarbons (pah) as the sole source of carbon and energy. the direct detection of sphingomonas strains in contaminated soils, either indigenous or inoculated, is, as such, of interest for bioremediation purposes. in this study, a culture-independent pcr-based detection method using specific primers targeting the sphingomonas 16s rrna gene combined with denaturing ...200415066784
root nodule bradyrhizobium spp. harbor tfdaalpha and cada, homologous with genes encoding 2,4-dichlorophenoxyacetic acid-degrading proteins.the distribution of tfdaalpha and cada, genes encoding 2,4-dichlorophenoxyacetate (2,4-d)-degrading proteins which are characteristic of the 2,4-d-degrading bradyrhizobium sp. isolated from pristine environments, was examined by pcr and southern hybridization in several bradyrhizobium strains including type strains of bradyrhizobium japonicum usda110 and bradyrhizobium elkanii usda94, in phylogenetically closely related agromonas oligotrophica and rhodopseudomonas palustris, and in 2,4-d-degradi ...200415066803
sphingomonas sp. strain sb5 degrades carbofuran to a new metabolite by hydrolysis at the furanyl ring.microorganisms capable of degrading carbofuran were isolated from soils and examined for the degradation of this pesticide at ring structure. an isolate that could degrade carbofuran and carbofuran-7-phenol was selected for further studies. the 16s rrna analysis results showed that the isolate belongs to the genus of sphingomonas, close to dioxin and dicamba degraders, and is named sphingomonas sp. sb5. sb5 did not show any similarity of 16s rrna to known carbofuran degraders. when time-course d ...200415080638
a novel tetrahydrofolate-dependent o-demethylase gene is essential for growth of sphingomonas paucimobilis syk-6 with syringate.sphingomonas paucimobilis syk-6 degrades syringate to 3-o-methylgallate (3mga), which is finally converted to pyruvate and oxaloacetate via multiple pathways in which protocatechuate 4,5-dioxygenase, 3mga dioxygenase, and gallate dioxygenase are involved. here we isolated the syringate o-demethylase gene (desa), which complemented the growth deficiency on syringate of a tn5 mutant of the syk-6 derivative strain. the desa gene is located 929 bp downstream of fera, encoding feruloyl-coenzyme a syn ...200415090517
origin and diversity of alginate lyases of families pl-5 and -7 in sphingomonas sp. strain a1.sphingomonas sp. strain a1 has three endotype alginate lyases (a1-i, a1-ii [family pl-7], and a1-iii [family pl-5]), each of which is encoded by a single gene. in addition to those of these lyases, a gene (the a1-ii' gene) showing significant identity with the a1-ii gene was present in the bacterial genome and coded for an alginate lyase with broad substrate specificity. since no expression of a1-ii' was observed even in bacterial cells grown on alginate, the a1-ii' gene was thought to be a sile ...200415090531
electrophoretically mediated microanalysis with partial filling technique and indirect or direct detection as a tool for inhibition studies of enzymatic reaction.the inhibition of the model enzyme, haloalkane dehalogenase from sphingomonas paucimobilis, was investigated by a combination of electrophoretically mediated microanalysis with a partial filling technique, followed by indirect or direct detection. in this setup, part of the capillary is filled with a buffer suitable for the enzymatic reaction (20 mm glycine buffer, ph 8.6) whereas the rest of the capillary is filled with the background electrolyte optimal for separation of substrates and product ...200415095444
bacteriophages and insertion sequences of chromobacterium violaceum atcc 12472.a fluid genome is a great advantage to prokaryotes, enabling quick adaptation to various types of ecological niches and to diverse environmental selective pressures. a substantial portion of these sudden changes is mediated by lateral gene transfer (lgt), through genetic recombination mechanisms, such as transformation, conjugation and transduction. the recent sequencing of several organisms has offered a new approach to the study of lgt, using comparison and analysis of nucleotide sequences dis ...200415100989
bacterial communities associated with flowering plants of the ni hyperaccumulator thlaspi goesingense.thlaspi goesingense is able to hyperaccumulate extremely high concentrations of ni when grown in ultramafic soils. recently it has been shown that rhizosphere bacteria may increase the heavy metal concentrations in hyperaccumulator plants significantly, whereas the role of endophytes has not been investigated yet. in this study the rhizosphere and shoot-associated (endophytic) bacteria colonizing t. goesingense were characterized in detail by using both cultivation and cultivation-independent te ...200415128517
microbial characterization of organic carrier colonization during a model biofiltration experiment.dynamic microbial characterization of the colonization of organic carrier during a model biofiltration experiment using methanol as air pollutant.200415130150
structure and function of a hypothetical pseudomonas aeruginosa protein pa1167 classified into family pl-7: a novel alginate lyase with a beta-sandwich fold.structural and functional analyses of alginate lyases are important in the clarification of the biofilm-dependent ecosystem in pseudomonas aeruginosa and in the development of therapeutic agents for bacterial disease. most alginate lyases are classified into polysaccharide lyase (pl) family-5 and -7 based on their primary structures. family pl-7 enzymes are still poorly characterized especially in structural properties. among family pl-7, a gene coding for a hypothetical protein (pa1167) homolog ...200415136569
heterologous gene expression in thermus thermophilus: beta-galactosidase, dibenzothiophene monooxygenase, pnb carboxy esterase, 2-aminobiphenyl-2,3-diol dioxygenase, and chloramphenicol acetyl transferase.enzymes from thermophiles are preferred for industrial applications because they generally show improved tolerance to temperature, pressure, solvents, and ph as compared with enzymes from mesophiles. however, nearly all thermostable enzymes used in industrial applications or available commercially are produced as recombinant enzymes in mesophiles, typically escherichia coli. the development of high-temperature bioprocesses, particularly those involving cofactor-requiring enzymes and/or multi-ste ...200415138843
sphingomonas yabuuchiae sp. nov. and brevundimonas nasdae sp. nov., isolated from the russian space laboratory mir.on the basis of phenotypic and genotypic characteristics and 16s rrna gene sequence analysis, novel species belonging to the genera sphingomonas and brevundimonas were identified from samples taken from the russian space laboratory mir. strain a1-18(t) was isolated from the air. 16s rdna sequence analysis showed that strain a1-18(t) formed a coherent cluster with sphingomonas sanguinis, sphingomonas parapaucimobilis, sphingomonas paucimobilis and sphingomonas roseiflava with sequence similarity ...200415143030
catellibacterium nectariphilum gen. nov., sp. nov., which requires a diffusible compound from a strain related to the genus sphingomonas for vigorous growth.a bacterial strain, designated ast4(t), was isolated from activated sludge. the bacterium did not show significant growth on nutrient broth, but growth was clearly stimulated by addition of supernatant from other bacterial cultures. culture filtrate of a strain related to the genus sphingomonas in particular increased the cell yield and growth rate of strain ast4(t). phylogenetic analysis based on the 16s rrna gene sequences showed that strain ast4(t) is located within the 'rhodobacter group' in ...200415143049
overexpression, purification, and characterization of atp-nad kinase of sphingomonas sp. a1.the nad kinase gene (nadk) of sphingomonas sp. a1 was cloned and then overexpressed in escherichia coli, and the gene product (nadk) was purified from the e. coli cells through five steps with a 25% yield of activity. nadk was a homodimer of 32 kda subunits, utilized atp or other nucleoside triphosphates, but not inorganic polyphosphates, as phosphoryl donors for the phosphorylation of nad, most efficiently at ph 8.0 and 50-55 degrees c, and was designated as atp-nad kinase (nadk). nadk showed n ...200415177293
characterization of degradation process of cyanobacterial hepatotoxins by a gram-negative aerobic bacterium.a bacterium termed 7cy, capable of decomposing cyanobacterial toxins, was isolated from surface water sample of lake suwa and degradation of microcystin-rr and nodularin-har was investigated. the isolated 7cy was a gram-negative, aerobic bacillus, and a member of a genus sphingomonas. the strain degraded microcystin-ly, -lw, and -lf completely as well as microcystin-lr within 4 days after their addition (6 microg/ml) whereas degradation of nodularin-har did not occur at all during experiment. on ...200415207597
treatment of atrazine by integrating photocatalytic and biological processes.this research examines the degradation of atrazine by photocatalytic oxidation (pco) under different experimental conditions. deisopropylatrazine, deethylatrazine and deethyldeisopropylatrazine were formed as major intermediates based on gas chromatography-mass spectrometry. the reaction mixture was found to be toxic towards two bioassays, i.e. the microtox and amphipods survival tests even when atrazine was completely degraded by pco within 2 h under optimized conditions. the results indicate t ...200415210274
isolation of adda from microcystin-lr by microbial degradation.the intact adda was isolated from microcystin-lr by a microbial degradation using an isolated sphingomonas strain, b-9. the reaction of microcystin-lr with cell extract of this strain proceeded smoothly to give the final degradation product by way of two intermediates, linearized microcystin-lr and a tetrapeptide. the purified adda that was structurally characterized using various spectral data did not show the toxicity to mice or inhibition to protein phosphatase activity in contrast to the nat ...200415225569
isolation and characterization of polycyclic aromatic hydrocarbons-degrading sphingomonas sp. strain zl5.a bacterial strain zl5, capable of growing on phenanthrene as a sole carbon and energy source but not naphthalene, was isolated by selective enrichment from crude-oil-contaminated soil of liaohe oil field in china. the isolate was identified as a sphingomonas sp. strain on the basis of 16s ribosomal dna analysis. strain zl5 grown on phenanthrene exhibited catechol 2,3-dioxygenase (c23o) activity but no catechol 1,2-dioxygenase, gentisate 1,2-dioxygenase, protocatechuate 3,4-dioxygenase and proto ...200415228078
molecular analysis of shower curtain biofilm microbes.households provide environments that encourage the formation of microbial communities, often as biofilms. such biofilms constitute potential reservoirs for pathogens, particularly for immune-compromised individuals. one household environment that potentially accumulates microbial biofilms is that provided by vinyl shower curtains. over time, vinyl shower curtains accumulate films, commonly referred to as "soap scum," which microscopy reveals are constituted of lush microbial biofilms. to determi ...200415240300
comparative biochemical analysis of three bacterial prolyl endopeptidases: implications for coeliac sprue.prolyl endopeptidases have potential for treating coeliac sprue, a disease of the intestine caused by proteolytically resistant peptides from proline-rich prolamins of wheat, barley and rye. we compared the properties of three similar bacterial prolyl endopeptidases, including the known enzymes from flavobacterium meningosepticum (fm) and sphingomonas capsulate (sc) and a novel enzyme from myxococcus xanthus (mx). these enzymes were interrogated with reference chromogenic substrates, as well as ...200415245330
are some putative glycogen accumulating organisms (gao) in anaerobic : aerobic activated sludge systems members of the alpha-proteobacteria?activated sludge plants designed to remove phosphorus microbiologically often perform unreliably. one suggestion is that the polyphosphate-accumulating organisms (pao) are out-competed for substrates by another group of bacteria, the glycogen-accumulating organisms (gao) in the anaerobic zones of these processes. this study used fluorescence in situ hybridization (fish) and denaturing gradient gel electrophoresis (dgge) to analyse the communities from laboratory-scale anaerobic : aerobic sequenc ...200415256569
mtbe biodegradation in a gravity flow, high-biomass retaining bioreactor.the aerobic biodegradation of methyl tert-butyl ether (mtbe), a widely used fuel oxygenate, was investigated using a pilot-scale biomass-retaining bioreactor called a biomass concentrator reactor (bcr). the reactor was operated for a year at a flow rate of 2500 l/d on cincinnati dechlorinated tap water and an influent mtbe concentration of 5 mg/l. treatment efficiency of mtbe in the reactor during stable operations exceeded 99.9%. the upper 95% confidence levels of effluent mtbe concentrations a ...200415260347
characterization of the 3-o-methylgallate dioxygenase gene and evidence of multiple 3-o-methylgallate catabolic pathways in sphingomonas paucimobilis syk-6.sphingomonas paucimobilis syk-6 is able to grow on various lignin-derived biaryls as the sole source of carbon and energy. these compounds are degraded to vanillate and syringate by the unique and specific enzymes in this strain. vanillate and syringate are converted to protocatechuate (pca) and 3-o-methylgallate (3mga), respectively, by the tetrahydrofolate-dependent o-demethylases. previous studies have suggested that these compounds are further degraded via the pca 4,5-cleavage pathway. howev ...200415262932
isolation of an exopolysaccharide-producing bacterium, sphingomonas sp. cs101, which forms an unusual type of sphingan.an exopolysaccharide-producing gram negative bacterium was isolated and determined to be a sphingomonas sp. (cs101). a sugar composition analysis of an exopolysaccharide indicated that the sphingomonas sp. cs101 secreted an exopolysaccharide composed of glucose, mannose, fucose, and rhamnose in the ratio of 2.1:1.1:1.0:0.1, suggesting that this exoplysaccharide is an unusual type of sphingan family. the mean molecular weight of the exopolysaccharide was determined to be 4.2x10(5) da by size excl ...200415170124
cross-species identification of proteins from proteome profiles of the marine oligotrophic ultramicrobacterium, sphingopyxis alaskensis.sphingopyxis (formerly sphingomonas) alaskensis is a model bacterium for studying adaptation to oligotrophy (nutrient-limitation). it has a unique physiology which is fundamentally different to that of the well studied bacteria such as escherichia coli. to begin to identify the genes involved in its physiological responses to nutrient-limited growth and starvation, we developed high resolution two-dimensional electrophoresis (2-de) methods and determined the identity of 12 proteins from a total ...200415174144
detection and characterization of conjugative degradative plasmids in xenobiotic-degrading sphingomonas strains.a systematic survey for the presence of plasmids in 17 different xenobiotic-degrading sphingomonas strains was performed. in almost all analyzed strains, two to five plasmids with sizes of about 50 to 500 kb were detected by using pulsed-field gel electrophoresis. a comparison of plasmid preparations untreated or treated with s1 nuclease suggested that, in general, sphingomonas plasmids are circular. hybridization experiments with labeled gene probes suggested that large plasmids are involved in ...200415175300
a novel nicotinoprotein aldehyde dehydrogenase involved in polyethylene glycol degradation.a gene (pegc) encoding aldehyde dehydrogenase (aldh) was located 3.4 kb upstream of a gene encoding polyethylene glycol (peg) dehydrogenase (pega) in sphingomonas macrogoltabidus strain 103. aldh was expressed in escherichia coli and purified on a ni-nitrilotriacetic acid agarose column. the recombinant enzyme was a homotetramer consisting of four 46.1-kda subunits. the alignment of the putative amino acid sequence of the cloned enzyme showed high similarity with a group of nad(p)-dependent aldh ...200515726348
degradation of anthracene and pyrene supplied by microcrystals and non-aqueous-phase liquids.polycyclic aromatic hydrocarbons (pahs) are worldwide environmental pollutants. their bioavailability is limited by a low aqueous solubility, which causes specific adaptations in degrading bacteria. to compare bacterial degrading behavior, a study was conducted on the mineralization, metabolization and formation of biomass from (14)c-anthracene by sphingomonas sp. ba2 compared with those from (14)c-pyrene by gordonia-like strain bp9 and mycobacterium gilvum vf1. different conditions of pah suppl ...200515729557
quantitative analysis of substrate specificity of haloalkane dehalogenase linb from sphingomonas paucimobilis ut26.haloalkane dehalogenases are microbial enzymes that cleave a carbon-halogen bond in halogenated compounds. the haloalkane dehalogenase linb, isolated from sphingomonas paucimobilis ut26, is a broad-specificity enzyme. fifty-five halogenated aliphatic and cyclic hydrocarbons were tested for dehalogenation with the linb enzyme. the compounds for testing were systematically selected using a statistical experimental design. steady-state kinetic constants k(m) and k(cat) were determined for 25 substr ...200515736949
structural and mechanistic analysis of two prolyl endopeptidases: role of interdomain dynamics in catalysis and specificity.prolyl endopeptidases (peps) are a unique class of serine proteases with considerable therapeutic potential for the treatment of celiac sprue. the crystal structures of two didomain peps have been solved in alternative configurations, thereby providing insights into the mode of action of these enzymes. the structure of the sphingomonas capsulata pep, solved and refined to 1.8-a resolution, revealed an open configuration of the active site. in contrast, the inhibitor-bound pep from myxococcus xan ...200515738423
bacterial glycolipids and analogs as antigens for cd1d-restricted nkt cells.the cd1 family of proteins binds self and foreign glycolipids for presentation to cd1-restricted t cells. to identify previously uncharacterized active cd1 ligands, especially those of microbial origin, numerous glycolipids were synthesized and tested for their ability to stimulate mouse and human natural killer t (nkt) cells. they included analogs of the well known nkt cell agonist alpha-galactosyl ceramide (alpha-galcer), bacterial glycolipids, and variations of the self-glycolipid, sulfatide. ...200515665086
a novel metabolic pathway for degradation of 4-nonylphenol environmental contaminants by sphingomonas xenophaga bayram: ipso-hydroxylation and intramolecular rearrangement.several nonylphenol isomers with alpha-quaternary carbon atoms serve as growth substrates for sphingomonas xenophaga bayram, whereas isomers containing hydrogen atoms at the alpha-carbon do not. three metabolites of 4-(1-methyloctyl)-phenol were isolated in mg quantities from cultures of strain bayram supplemented with the growth substrate isomer 4-(1-ethyl-1,4-dimethyl-pentyl)-phenol. they were unequivocally identified as 4-hydroxy-4-(1-methyl-octyl)-cyclohexa-2,5-dienone, 4-hydroxy-4-(1-methyl ...200515665329
identification of insertion sequence from a gamma-hexachlorocyclohexane degrading bacterium, sphingomonas paucimobilis ut26.tn5-derived mutants of the gamma-hexachlorocyclohexane-degrading bacterium sphingomonas paucimobilis ut26 were genetically characterized, and an endogenous insertion sequence (is) which belongs to the is1380 family was identified. the is, named issp1, existed as multi copies in ut26, and its transposition appeared to be activated during the process of tn5-mutagenesis. it was found that transposon mutagenesis can cause endogenous mutations.200515665490
evolutionarily divergent extradiol dioxygenases possess higher specificities for polychlorinated biphenyl metabolites.the reactivities of four evolutionarily divergent extradiol dioxygenases towards mono-, di-, and trichlorinated (tricl) 2,3-dihydroxybiphenyls (dhbs) were investigated: 2,3-dihydroxybiphenyl dioxygenase (ec 1.13.11.39) from burkholderia sp. strain lb400 (dhbdlb400), dhbdp6-i and dhbdp6-iii from rhodococcus globerulus p6, and 2,2',3-trihydroxybiphenyl dioxygenase from sphingomonas sp. strain rw1 (thbdrw1). the specificity of each isozyme for particular dhbs differed by up to 3 orders of magnitude ...200515629912
catabolic role of a three-component salicylate oxygenase from sphingomonas yanoikuyae b1 in polycyclic aromatic hydrocarbon degradation.sphingomonas yanoikuyae b1 possesses several different multicomponent oxygenases involved in metabolizing aromatic compounds. six different pairs of genes encoding large and small subunits of oxygenase iron-sulfur protein components have previously been identified in a gene cluster involved in the degradation of both monocyclic and polycyclic aromatic hydrocarbons. insertional inactivation of one of the oxygenase large subunit genes, bpha1c, results in a mutant strain unable to grow on naphthale ...200515649397
identification and characterization of genes involved in the downstream degradation pathway of gamma-hexachlorocyclohexane in sphingomonas paucimobilis ut26.sphingomonas paucimobilis ut26 utilizes gamma-hexachlorocyclohexane (gamma-hch) as a sole source of carbon and energy. in our previous study, we cloned and characterized genes that are involved in the conversion of gamma-hch to maleylacetate (ma) via chlorohydroquinone (chq) in ut26. in this study, we identified and characterized an ma reductase gene, designated linf, that is essential for the utilization of gamma-hch in ut26. a gene named lineb, whose deduced product showed significant identity ...200515659662
characterization of micro-organisms isolated from dairy industry after cleaning and fogging disinfection with alkyl amine and peracetic acid.to characterize micro-organisms isolated from norwegian dairy production plants after cleaning and fogging disinfection with alkyl amine/peracetic acid and to indicate reasons for survival.200515610421
phosphonium ionic liquids for degradation of phenol in a two-phase partitioning bioreactor.six ionic liquids (ils), which are organic salts that are liquid at room temperature, were tested for their biocompatibility with three xenobiotic-degrading bacteria, pseudomonas putida, achromobacter xylosoxidans, and sphingomonas aromaticivorans. of the 18 pairings, seven were found to demonstrate biocompatibility, with one il (trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl) amide) being biocompatible with all three organisms. this il was then used in a two-phase partitioning bior ...200515549289
influence of the carbon/nitrogen/phosphorus ratio on polycyclic aromatic hydrocarbon degradation by mycobacterium and sphingomonas in soil.biodegradation of polycyclic aromatic hydrocarbons (pahs) in the environment is often limited due to unfavorable nutrient conditions for the bacteria that use these pahs as sole source of carbon and energy. mycobacterium and sphingomonas are 2 pah-degrading specialists commonly present in pah-polluted soil, but not much is known about their specific nutrient requirements. by adding different inorganic supplements of nitrogen (n) and phosphorus (p), affecting the overall carbon/nitrogen/phosphoru ...200515549290
recognition of bacterial glycosphingolipids by natural killer t cells.natural killer t (nkt) cells constitute a highly conserved t lymphocyte subpopulation that has the potential to regulate many types of immune responses through the rapid secretion of cytokines. nkt cells recognize glycolipids presented by cd1d, a class i-like antigen-presenting molecule. they have an invariant t-cell antigen receptor (tcr) alpha-chain, but whether this invariant tcr recognizes microbial antigens is still controversial. here we show that most mouse and human nkt cells recognize g ...200515791257
exogenous and endogenous glycolipid antigens activate nkt cells during microbial infections.cd1d-restricted natural killer t (nkt) cells are innate-like lymphocytes that express a conserved t-cell receptor and contribute to host defence against various microbial pathogens. however, their target lipid antigens have remained elusive. here we report evidence for microbial, antigen-specific activation of nkt cells against gram-negative, lipopolysaccharide (lps)-negative alpha-proteobacteria such as ehrlichia muris and sphingomonas capsulata. we have identified glycosylceramides from the ce ...200515791258
direct evidence for sphingomonas sp. a1 periplasmic proteins as macromolecule-binding proteins associated with the abc transporter: molecular insights into alginate transport in the periplasm.a gram-negative bacterium, sphingomonas sp. a1, has a macromolecule (alginate) import system consisting of a pit on the cell surface and an alginate-specific atp-binding cassette importer in the inner membrane. transport of alginate from the pit to the abc importer is probably mediated by two periplasmic binding protein homologues (algq1 and algq2). here we describe characteristics of binding of algq1 and algq2 to alginate and its oligosaccharides through surface plasmon resonance biosensor anal ...200515794643
diversity of carbazole-degrading bacteria having the car gene cluster: isolation of a novel gram-positive carbazole-degrading bacterium.twenty-seven carbazole-utilizing bacterial strains were isolated from environmental samples, and were classified into 14 groups by amplified ribosomal dna restriction analysis. southern hybridization analyses showed that 3 and 17 isolates possessed the car gene homologs of pseudomonas resinovorans ca10 and sphingomonas sp. strain ka1, respectively. of the 17 isolates, 2 isolates also have the homolog of the caraa gene of sphingomonas sp. strain cb3. while the genome of one isolate, a gram-positi ...200515796992
a tetrahydrofolate-dependent o-demethylase, ligm, is crucial for catabolism of vanillate and syringate in sphingomonas paucimobilis syk-6.vanillate and syringate are converted into protocatechuate (pca) and 3-o-methylgallate (3mga), respectively, by o-demethylases in sphingomonas paucimobilis syk-6. pca is further degraded via the pca 4,5-cleavage pathway, while 3mga is degraded through multiple pathways in which pca 4,5-dioxygenase (ligab), 3mga 3,4-dioxygenase (desz), and an unidentified 3mga o-demethylase and gallate dioxygenase are participants. for this study, we isolated a 4.7-kb smai fragment that conferred on escherichia c ...200515743951
differential degradation of nonylphenol isomers by sphingomonas xenophaga bayram.sphingomonas xenophaga bayram, isolated from the activated sludge of a municipal wastewater treatment plant, was able to utilize 4-(1-ethyl-1,4-dimethylpentyl)phenol, one of the main isomers of technical nonylphenol mixtures, as a sole carbon and energy source. the isolate degraded 1 mg of 4-(1-ethyl-1,4-dimethylpentyl)phenol/ml in minimal medium within 1 week. growth experiments with five nonylphenol isomers showed that the three isomers with quaternary benzylic carbon atoms [(1,1,2,4-tetrameth ...200515746308
9,10-phenanthrenequinone photoautocatalyzes its formation from phenanthrene, and inhibits biodegradation of naphthalene.polycyclic aromatic hydrocarbons (pahs) have earned considerable attention due to their widespread environmental distribution and toxicity. in the environment, pahs decompose by a variety of biotic and abiotic pathways. in both polar and nonpolar environments, phenanthrene (phe, a common, three-ring pah) is converted by sunlight to more polar products such as 9,10-phenanthrenequinone (pheq) and subsequent oxidation products such as the corresponding open-ring dicarboxylic acid product. biodegrad ...200515758098
[oligotrophic bacteria and their applications in environmental science].oligotrophic bacteria are a group of microbes living in oligotrophic environments. their diversity and biomass are dominant in biosphere, and thus, play an important role in biogeochemical cycles. since 1980s, their oligotrophic mechanisms, responses to starvation, and roles in ecosystems have been one of the most advanced subjects in microbial ecological research. much attention has been paid to the theoretical values and applied perspectives of oligotrophic bacteria. this paper reviewed the co ...200516011186
molecular characterization of the gallate dioxygenase from pseudomonas putida kt2440. the prototype of a new subgroup of extradiol dioxygenases.in this work we have characterized the gala gene product from pseudomonas putida kt2440, a ring-cleavage dioxygenase that acts specifically on gallate to produce 4-oxalomesaconate. the protein is a trimer composed by three identical subunits of 47.6 kda (419 amino acids) that uses fe2+ as the main cofactor. the gallate dioxygenase showed maximum activity at ph 7.0, and the km and vmax values for gallate were 144 microm and 53.2 micromol/min/mg of protein, respectively. a phylogenetic study sugge ...200516030014
characterization of the gallate dioxygenase gene: three distinct ring cleavage dioxygenases are involved in syringate degradation by sphingomonas paucimobilis syk-6.sphingomonas paucimobilis syk-6 converts vanillate and syringate to protocatechuate (pca) and 3-o-methylgallate (3mga) in reactions with the tetrahydrofolate-dependent o-demethylases ligm and desa, respectively. pca is further degraded via the pca 4,5-cleavage pathway, whereas 3mga is metabolized via three distinct pathways in which pca 4,5-dioxygenase (ligab), 3mga 3,4-dioxygenase (desz), and 3mga o-demethylase (ligm) are involved. in the 3mga o-demethylation pathway, ligm converts 3mga to gall ...200516030198
isolation and identification of sphingomonas sp. that yields tert-octylphenol monoethoxylate under aerobic conditions.topsoil samples were collected from eight golf courses in yamaguchi prefecture, japan, and enrichment cultures were carried out with a basal-salt medium containing 0.2% 4-tert-octylphenol polyethoxylate (oppeo) as sole carbon source. oppeo-degrading activity was detected in one of the samples, from which a strain of oppeo-degrading bacterium was isolated. the isolated bacterium grew on a nutritionally enriched medium (ne medium) containing 0.2% oppeo as sole carbon source, and accumulated 4-tert ...200516041123
a mechanistic investigation of the thiol-disulfide exchange step in the reductive dehalogenation catalyzed by tetrachlorohydroquinone dehalogenase.tetrachlorohydroquinone dehalogenase catalyzes the reductive dehalogenation of tetrachloro- and trichlorohydroquinone to give 2,6-dichlorohydroquinone in the pathway for degradation of pentachlorophenol by sphingobium chlorophenolicum. previous work has suggested that this enzyme may have originated from a glutathione-dependent double bond isomerase such as maleylacetoacetate isomerase or maleylpyruvate isomerase. while some of the elementary steps in these two reactions may be similar, the fina ...200516042413
taking the fungal highway: mobilization of pollutant-degrading bacteria by fungi.the capacity of fungi to serve as vectors for the dispersion of pollutant-degrading bacteria was analyzed in laboratory model systems mimicking water-saturated (agar surfaces) and unsaturated soil environments (glass-bead-filled columns). two common soil fungi (fusarium oxysporum and rhexocercosporidium sp.) forming hydrophilic and hydrophobic mycelia, respectively, and three polycyclic aromatic hydrocarbon degrading bacteria (achromobacter sp. sk1, mycobacterium frederiksbergense lb501tg, and s ...200516047804
cis-dihydrodiol, arene oxide and phenol metabolites of dictamnine: key intermediates in the biodegradation and biosynthesis of furoquinoline alkaloids.biotransformation of the parent furoquinoline alkaloid dictamnine and its 4-chlorofuroquinoline precursor, using the b8/36 bacterial mutant strain of sphingomonas yanoikuyae, yielded, via biphenyl dioxygenase-catalysed dihydroxylation, the first isolable alkaloid cis-dihydrodiol metabolites; these metabolites were used in the chemoenzymatic synthesis of postulated arene oxide and phenol intermediates, and a range of derived furoquinoline alkaloids.200516075095
physicochemical properties and biological activities of deae-derivatized sphingomonas gellan.physicochemical characteristics and biological activities of sphingomonas gellan (s-gellan) were investigated. the s-gellan weight fractions of glc and glcua were 0.45 and 0.25, respectively, and the molar ratio of glc:rha:glcua was approximately 4:2:3. the s-gellan was chemically derivatized with diethylaminoethyl chloride-hcl (deae-hcl), and the resulting modified s-gellan contained both positive and negative charges. the elemental and ir analyses were conducted to confirm the successful incor ...200516076099
a structural basis for depolymerization of alginate by polysaccharide lyase family-7.alginate lyases depolymerize alginate, a heteropolysaccharide consisting of alpha-l-guluronate and beta-d-mannuronate, through a beta-elimination reaction. their structure/function relationships are expected to provide information valuable to future industrial alginate processing and drug design for pseudomonas aeruginosa alginate biofilm-dependent infection, but much remains unknown. here, we present the crystal structure at 1.0 a resolution and the results of mutational analysis of sphingomona ...200516081095
proteins encoded by sphingomonas elodea atcc 31461 rmla and ugpg genes, involved in gellan gum biosynthesis, exhibit both dtdp- and udp-glucose pyrophosphorylase activities.the commercial gelling agent gellan is a heteropolysaccharide produced by sphingomonas elodea atcc 31461. in this work, we carried out the biochemical characterization of the enzyme encoded by the first gene (rmla) of the rml 4-gene cluster present in the 18-gene cluster required for gellan biosynthesis (gel cluster). based on sequence homology, the putative rml operon is presumably involved in the biosynthesis of dtdp-rhamnose, the sugar necessary for the incorporation of rhamnose in the gellan ...200516085866
degradation of chlorophenols using pentachlorophenol-degrading bacteria sphingomonas chlorophenolica in a batch reactor.chlorophenols are common environmental contaminants that have been used as the major component in wide-spectrum biocides in industry and agriculture. many chlorophenols tend to persist in the environment and may become public health hazards. this research studied the ability of the pentachlorophenol (pcp)-degrading bacterium sphingomonas chlorophenolica to degrade and dechlorinate other chlorophenols. in addition, the characteristics of s. chlorophenolica were also investigated. when s. chloroph ...200516086107
degradation of beta-hexachlorocyclohexane by haloalkane dehalogenase linb from sphingomonas paucimobilis ut26.beta-hexachlorocyclohexane (beta-hch) is the most recalcitrant among the alpha-, beta-, gamma-, and delta-isomers of hch and causes serious environmental pollution problems. we demonstrate here that the haloalkane dehalogenase linb, reported earlier to mediate the second step in the degradation of gamma-hch in sphingomonas paucimobilis ut26, metabolizes beta-hch to produce 2,3,4,5,6-pentachlorocyclohexanol.200515812056
characterization of sphingomonas aldehyde dehydrogenase catalyzing the conversion of various aromatic aldehydes to their carboxylic acids.an aldehyde dehydrogenase gene, designated phnn, was isolated from a genome library of the 1,4-dimethylnaphthalene-utilizing soil bacterium, sphingomonas sp. 14dn61. escherichia coli expressing the phnn gene converted 1,4-dihydroxymethylnaphthalene to 1-hydroxymethyl-4-naphthoic acid. the putative amino acid sequence of the phnn gene product had 31-42% identity with those of nad(+)-dependent short-chain aliphatic aldehyde dehydrogenases and a secondary alcohol dehydrogenase. the nad(p)(+)-bindin ...200515812642
biochemical and molecular characterization of a periplasmic hydrolase for oxidized polyvinyl alcohol from sphingomonas sp. strain 113p3.oxidized polyvinyl alcohol hydrolase (oph) and polyvinyl alcohol dehydrogenase were found to be constitutively present in the periplasm of sphingomonas sp. strain 113p3 (formerly pseudomonas sp. 113p3). the oph was purified to homogeneity with a yield of 40 % and a 5.9-fold increase in specific activity. the enzyme was a homodimer consisting of 35 kda subunits. its activity was inhibited by pmsf, hg(2+) and zn(2+). the enzyme hydrolysed oxidized polyvinyl alcohol (oxidized pva) and p-nitrophenyl ...200515817792
osteomyelitis and secondary septic arthritis caused by sphingomonas paucimobilis.we describe a case of osteomyelitis and secondary septic arthritis caused by sphingomonas paucimobilis in an immunosupressed adolescent which did not present typically, leading to a delay in diagnosis. this case highlights the need to thoroughly investigate musculoskeletal pain in the immunocompromised patient in order to exclude an infection as a cause.200515827879
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