Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| degradation of the cyanobacterial hepatotoxin microcystin by a new bacterium isolated from a hypertrophic lake. | a bacterium capable of degrading microcystins-rr, -yr, and -lr was isolated from a hypertrophic lake. the bacterium, designated y2 and classified phenotypically as a member of the genus sphingomonas, was shown to be distinct phylogenetically from any established species of sphingomonas on the basis of 16s rdna sequencing. the bacterium was tentatively identified as sphingomonas by manual chemotaxonomy, but 16s rrna sequencing analysis suggests that it is in fact a new species or even a new genus ... | 2001 | 11501283 |
| biochemical characterization of the beta-1,4-glucuronosyltransferase gelk in the gellan gum-producing strain sphingomonas paucimobilis a.t.c.c. 31461. | biosynthesis of bacterial polysaccharide-repeat units proceeds by sequential transfer of sugars, from the appropriate sugar donor to an activated lipid carrier, by committed glycosyltransferases (gts). few studies on the mechanism of action for this type of gt are available. sphingomonas paucimobilis a.t.c.c. 31461 produces the industrially important polysaccharide gellan gum. we have cloned the gelk gene from s. paucimobilis a.t.c.c. 31461. gelk belongs to family 1 of the gt classification [cam ... | 2001 | 11513745 |
| detection of mega plasmid from polycyclic aromatic hydrocarbon-degrading sphingomonas sp. strain ks14. | polycyclic aromatic hydrocarbon (pah) degrading sphingomonas sp. strain ks14 was isolated from soil. strain ks14 was able to utilize phenanthrene and naphthalene as sole source of carbon and energy, and mineralize phenanthrene to carbon dioxide. strain ks14 cometabolically degraded pyrene using phenanthrene as secondary growth substrate. a large degradative plasmid (>500 kb) was detected from the strain ks14. this study suggests that this mega plasmid could be responsible for the degradation of ... | 2001 | 11545268 |
| microbial deracemization of 1-aryl and 1-heteroaryl secondary alcohols. | 2001 | 11559206 | |
| convergent and divergent points in catabolic pathways involved in utilization of fluoranthene, naphthalene, anthracene, and phenanthrene by sphingomonas paucimobilis var. epa505. | catabolic pathways for utilization of naphthalene (nap), anthracene (ant), phenanthrene (phe), and fluoranthene (fla) by sphingomonas paucimobilis epa505 were identified. accumulation of catabolic intermediates was investigated with three classes of tn5 mutants with the following polycyclic aromatic hydrocarbon (pah)-negative phenotypes; (class i nap(-) phe(-) fla(-), class ii nap(-) phe(-), and class iii fla(-)). class i mutant 200pbha had a tn5 insertion within a meta ring fission dioxygenase ... | 2001 | 11571621 |
| colorimetric assay for lindane dechlorination by bacteria. | a colorimetric microtitre plate-based assay that detects haloalkane dehalogenase activity was modified to detect dechlorination of gamma-hexachlorocyclohexane (lindane). dechlorination is indicated by the colour change of phenol red from red to yellow, in a weakly buffered solution, as the solution becomes acidic due to hcl formed during dechlorination. enzyme activity can be monitored by reading the absorbance of each well at 540 nm. positive controls for the assay were the known lindane-degrad ... | 2001 | 11576682 |
| effects of nonionic surfactants on bacterial transport through porous media. | nonionic surfactants of the form cxey, where x is the number of carbons in the alkyl chain and y is the number of ethylene oxide units in the polyoxyethylene (poe) chain, were studied for their ability to alter the transport of sphingomonas pacilimobilis through an aquifer sand. the surfactants c12e4 (brij 30) and c12e23 (brij 35) were the focus of this study. through a systematic study, it was shown that these nonionic surfactants were able to enhance the transport of this bacterial culture thr ... | 2001 | 11642447 |
| the first step in polyethylene glycol degradation by sphingomonads proceeds via a flavoprotein alcohol dehydrogenase containing flavin adenine dinucleotide. | several sphingomonas spp. utilize polyethylene glycols (pegs) as a sole carbon and energy source, oxidative peg degradation being initiated by a dye-linked dehydrogenase (peg-dh) that oxidizes the terminal alcohol groups of the polymer chain. purification and characterization of peg-dh from sphingomonas terrae revealed that the enzyme is membrane bound. the gene encoding this enzyme (pega) was cloned, sequenced, and expressed in escherichia coli. the purified recombinant enzyme was vulnerable to ... | 2001 | 11673442 |
| super-channel in bacteria: function and structure of a macromolecule import system mediated by a pit-dependent abc transporter. | in a soil isolate, sphingomonas sp. a1, the transport of a macromolecule (alginate: 27 kda) is mediated by a pit-dependent atp-binding cassette (abc) transporter. the transporter is different from other abc transporters so far analyzed in that its function is dependent on the pit, a mouth-like organ formed on the cell surface only when the cells are compelled to assimilate macromolecules, and in that it allows direct import of macromolecules into cells. the abc transporter coupled with the pit, ... | 2001 | 11676004 |
| sphingomonas alaskensis strain afo1, an abundant oligotrophic ultramicrobacterium from the north pacific. | numerous studies have established the importance of picoplankton (microorganisms of < or =2 microm in length) in energy flow and nutrient cycling in marine oligotrophic environments, and significant effort has been directed at identifying and isolating heterotrophic picoplankton from the world's oceans. using a method of diluting natural seawater to extinction followed by monthly subculturing for 12 months, a bacterium was isolated that was able to form colonies on solid medium. the strain was i ... | 2001 | 11679312 |
| isolation of bacteria and 16s rdnas from lake vostok accretion ice. | lake vostok, the largest subglacial lake in antarctica, is separated from the surface by approximately 4 km of glacial ice. it has been isolated from direct surface input for at least 420 000 years, and the possibility of a novel environment and ecosystem therefore exists. lake vostok water has not been sampled, but an ice core has been recovered that extends into the ice accreted below glacial ice by freezing of lake vostok water. here, we report the recovery of bacterial isolates belonging to ... | 2001 | 11683867 |
| production and characterization of the recombinant sphingomonas chlorophenolica pentachlorophenol 4-monooxygenase. | pentachlorophenol 4-monooxygenase (pcp4mo) from sphingomonas chlorophenolica is a flavoprotein that hydroxylates pcp in the presence of nadph and oxygen. in order to investigate the structure and function of active site, recombinant pcp4mo (repcp4mo) was produced in escherichia coli as a glutathione s-transferase (gst) fusion protein. moreover, a tobacco etch virus (tev) protease cleavage site (eklyfqg) was introduced into gst-pcp4mo and a his-tagged tev protease was employed. hence, a two-step ... | 2001 | 11708794 |
| temperature- and growth-phase-regulated changes in lipid fatty acid structures of psychrotolerant groundwater proteobacteria. | cellular fatty acid compositions of five psychrotolerant groundwater isolates representing alpha- and beta-proteobacteria were studied at temperatures ranging from 8 to 25 degrees c. unsaturation of straight-chain fatty acids was the most common response to decreasing temperature and was detected in four of the isolates. on solid media, decrease of temperature resulted in a decrease of cyclopropane fatty acids in beta-proteobacterial isolates. the formation of cyclopropane fatty acids depended, ... | 2001 | 11797043 |
| microflora investigation experiment. | many microorganisms were isolated from condensed water, wiping and scratching of cabin wall and air sampler in russian space station mir by russian astronauts lazutkin et al. in february 1997 as part of nasda "first mir utilization space experiment (jmir)". for example, there were about 2 x 10(6) cells/ml in condensed water sample no. 1 isolated from the transfer-docking compartment of crystal module. we tried the colony isolation, pure culturing and identification from these sampled microorgani ... | 2001 | 11799257 |
| 16s rdna sequence analysis of bacterial isolates from biodeteriorated mural paintings in the servilia tomb (necropolis of carmona, seville, spain). | bacteria were isolated from damaged mural paintings of the servilia tomb (necropolis of carmona, seville, spain). selected strains, representative for different clusters of isolates with similar fatty acid profiles, were analysed by 16s rdna sequence analysis. bacillus is the dominant genus among the isolates: members of the rrna species complexes of b. megaterium, b. pumilus and b. firmus were found as well as several other bacillus species. one group of halotolerant isolates falls in the bacil ... | 2001 | 11822679 |
| dna-based and culture-based characterization of a hydrocarbon-degrading consortium enriched from arctic soil. | a hydrocarbon-degrading consortium was enriched from fuel-contaminated soil from the northeastern tip of ellesmere island (82 degrees 30'n, 62 degrees 19'w). the enrichment culture was grown on jet a-1 fuel at 7 degrees c. bacterial 16s rna gene (rdna) fragments were amplified by polymerase chain reaction (pcr) from members of the above consortium and cloned into a plasmid vector. partial sequences (approximately 500 bp) were determined for 29 randomly selected rdna clones. the majority of seque ... | 2001 | 11822837 |
| [the application of genetic engineering to the petroleum biodesulfurization]. | the developed course and reaction mechanisms of petroleum biodesulfurization were introduced. the recent development of genetic engineering technology, which used in desulfuration strain's construction, reconstruction and other fields, was summarized emphatically. its current research situation internal and overseas and the developing prospect were simply analyzed, and our research designs were submitted. | 2001 | 11910751 |
| crystal structure of alginate lyase a1-iii complexed with trisaccharide product at 2.0 a resolution. | the structure of a1-iii from a sphingomonas species a1 complexed with a trisaccharide product (4-deoxy-l-erythro-hex-4-enepyranosyluronate-mannuronate-mannuronic acid) was determined by x-ray crystallography at 2.0 a with an r-factor of 0.16. the final model of the complex form comprising 351 amino acid residues, 245 water molecules, one sulfate ion and one trisaccharide product exhibited a c(alpha) r.m.s.d. value of 0.154 a with the reported apo form of the enzyme. the trisaccharide was bound i ... | 2001 | 11243798 |
| altering catalytic properties of 3-chlorocatechol-oxidizing extradiol dioxygenase from sphingomonas xenophaga bn6 by random mutagenesis. | the 2,3-dihydroxybiphenyl 1,2-dioxygenase from sphingomonas xenophaga strain bn6 (bphc1) oxidizes 3-chlorocatechol by a rather unique distal ring cleavage mechanism. in an effort to improve the efficiency of this reaction, bphc1 was randomly mutated by error-prone pcr. mutants which showed increased activities for 3-chlorocatechol were obtained, and the mutant forms of the enzyme were shown to contain two or three amino acid substitutions. variant enzymes containing single substitutions were con ... | 2001 | 11244073 |
| molecular organization of the ribosomal rna transcription unit and the phylogenetic study of zymomonas mobilis zm4. | previously we reported that zymomonas mobilis zm4 contains three ribosomal transcription units (rrna to c operons) which are clustered around the 50 min region, paci fragments 13 and 6, on the physical map of z. mobilis zm4 [kang, h. l. and kang, h. s. (1998) gene 206, 223-228]. the physical map reveals that the rrna gene set is located on the 76 kb paci fragment 13. the complete nucleotide sequence of the rrna gene set has been determined. the total number of nucleotides of the rrna gene set is ... | 2001 | 11266123 |
| a water-soluble homodimeric serine palmitoyltransferase from sphingomonas paucimobilis ey2395t strain. purification, characterization, cloning, and overproduction. | serine palmitoyltransferase (spt, ec ) is a key enzyme in sphingolipid biosynthesis and catalyzes the decarboxylative condensation of l-serine and palmitoyl-coenzyme a to 3-ketodihydrosphingosine. we found that the gram-negative obligatory aerobic bacteria sphingomonas paucimobilis ey2395(t) have significant spt activity and purified spt to homogeneity. this enzyme is a water-soluble homodimeric protein unlike eukaryotic enzymes, known as heterodimers composed of tightly membrane-bound subunits, ... | 2001 | 11279212 |
| a rapid method to screen degradation ability in chlorophenoxyalkanoic acid herbicide-degrading bacteria. | an agar medium containing a range of related chlorophenoxyalkanoic acid herbicides, 2,4-dichlorophenoxyacetic acid (2,4-d), 2-methyl-4-chlorophenoxyacetic acid (mcpa), racemic mecoprop, (r)-mecoprop and racemic 2,4-dp (2-(2,4-dichlorophenoxy) propionic acid) was developed to assess the catabolic activity of a range of degradative strains. | 2001 | 11298940 |
| proposal of sphingomonas wittichii sp. nov. for strain rw1t, known as a dibenzo-p-dioxin metabolizer. | a polyphasic taxonomic study was performed on sphingomonas sp. strain rw1t. the organism was isolated from water of the river elbe and has been known as a potent metabolizer of dibenzo-p-dioxin and its relatives. tlc of a mild alkaline hydrolysate of extractable cellular lipids of strain rw1t and type strains of 21 sphingomonas species gave a spot of sphingoglycolipid (sgl)-1 (glucuronosyl ceramide), which is characteristic of sphingomonads. in addition, strain rw1t and type strains of three sph ... | 2001 | 11321072 |
| sphingomonas cloacae sp. nov., a nonylphenol-degrading bacterium isolated from wastewater of a sewage-treatment plant in tokyo. | a nonylphenol-assimilating bacterium isolated at a sewage-treatment plant in tokyo was studied phenotypically, genotypically and phylogenetically. analysis of the 16s rdna sequence, the g+c content of the dna (63 mol%) and the isoprenoid quinone composition, as well as the presence of sphingoglycolipid and the whole-cell fatty acid profile, revealed that the isolate is a member of the genus sphingomonas. however, the sequence similarity of the 16s rdna with that of known sphingomonas spp. was fo ... | 2001 | 11321106 |
| isolation and characterization of the genes encoding a novel oxygenase component of angular dioxygenase from the gram-positive dibenzofuran-degrader terrabacter sp. strain dbf63. | a gram-positive bacterium terrabacter sp. strain dbf63 is able to degrade dibenzofuran (df) via initial dioxygenation by a novel angular dioxygenase. the dbfa1 and dbfa2 genes, which encode the large and small subunits of the dibenzofuran 4,4a-dioxygenase (dfdo), respectively, were isolated by a polymerase chain reaction-based method. dbfa1 and dbfa2 showed moderate homology to the large and small subunits of other ring-hydroxylating dioxygenases (less than 40%), respectively, and some motifs su ... | 2001 | 11322788 |
| enzymatic synthesis of chiral intermediates for omapatrilat, an antihypertensive drug. | biocatalytic processes were used to prepare chiral intermediates required for the synthesis of omapatrilat 1 by three different routes. the synthesis and enzymatic conversion of 2-keto-6-hydroxyhexanoic acid 3 to l-6-hydroxynorleucine 2 was demonstrated by reductive amination using beef liver glutamate dehydrogenase. to avoid the lengthy chemical synthesis of the ketoacid 3, a second route was developed to prepare the ketoacid by treatment of racemic 6-hydroxy norleucine [readily available from ... | 2001 | 11337276 |
| fluoranthene-2,3- and -1,5-diones are novel products from the bacterial transformation of fluoranthene. | fluoranthene is one of the predominant compounds found in soils and sediments contaminated with polycyclic aromatic hydrocarbons (pah). four bacterial strains isolated from pah-contaminated soils transformed fluoranthene to a number of products during growth on phenanthrene, including the novel metabolites fluoranthene-2,3-dione (f23q) and fluoranthene-1,5-dione (f15q). given the known toxicity and mutagenicity of f23q, we focused on characterizing this metabolite with respect to its effects on ... | 2001 | 11351535 |
| molecular detection of marine bacterial populations on beaches contaminated by the nakhodka tanker oil-spill accident. | in january 1997, the tanker nakhodka sank in the japan sea, and more than 5000 tons of heavy oil leaked. the released oil contaminated more than 500 km of the coastline, and some still remained even by june 1999. to investigate the long-term influence of the nakhodka oil spill on marine bacterial populations, sea water and residual oil were sampled from the oil-contaminated zones 10, 18, 22 and 29 months after the accident, and the bacterial populations in these samples were analysed by denaturi ... | 2001 | 11359510 |
| aminopeptidase from sphingomonas capsulata. | a novel aminopeptidase with unique substrate specificity was purified from a culture broth of sphingomonas capsulata. this is the first reported aminopeptidase to demonstrate broad substrate specificity and yet release glycine and alanine with the highest efficacy. on a series of pentapeptide amides with different n-terminal amino acids, this enzyme efficiently releases glycine, alanine, leucine, proline, and glutamate with the lowest turnover value of 370 min(-1) for glutamate. at ph 7.5 (ph op ... | 2001 | 11359790 |
| isolation and characterization of polycyclic aromatic hydrocarbon-degrading bacteria associated with the rhizosphere of salt marsh plants. | polycyclic aromatic hydrocarbon (pah)-degrading bacteria were isolated from contaminated estuarine sediment and salt marsh rhizosphere by enrichment using either naphthalene, phenanthrene, or biphenyl as the sole source of carbon and energy. pasteurization of samples prior to enrichment resulted in isolation of gram-positive, spore-forming bacteria. the isolates were characterized using a variety of phenotypic, morphologic, and molecular properties. identification of the isolates based on their ... | 2001 | 11375181 |
| crystallization and preliminary x-ray analysis of algs, a bacterial atp-binding cassette (abc) protein specific to macromolecule import. | sphingomonas sp. a1 possesses a macromolecule (alginate; average molecular size 25 700 da) uptake system mediated by a novel pit-dependent abc transporter. in this system, algs (363 amino-acid residues; 40 kda) functions as an atpase and provides energy for the translocation of high molecular-weight alginate across the cytoplasmic membrane. hexahistidine-tagged algs of sphingomonas sp. a1 was overexpressed in escherichia coli and crystallized by means of the hanging-drop vapour-diffusion method ... | 2001 | 11375517 |
| time-resolved study of biofilm architecture and transport processes using experimental and simulation techniques: the role of eps. | cellular material and extracellular polymeric substances are the basic structural elements in biofilm systems. the structure and role of eps for biofilm development and metabolic processes have not been precisely determined and, therefore, have not yet been included as a necessary element in modelling and simulation studies. this is due to the difficulty of experimentally detecting the extracellular polymeric substances in situ and differentiating them from cellular material on the one hand, and ... | 2001 | 11381960 |
| location of o-acetyl groups in s-657 using the reductive-cleavage method. | a two-step procedure is described in this paper to identify the position of o-acetyl groups in s-657 polysaccharide. reductive-cleavage experiments performed on the fully methylated (base-catalyzed) polysaccharide, followed by acetylation of anhydroalditols, identified individual sugar residues and their position of linkage. in a second experiment, the polysaccharide was methylated under neutral conditions leaving native acetate groups intact. reductive cleavage of the neutral methylated polysac ... | 2001 | 11383896 |
| structural studies of s-7, another exocellular polysaccharide containing 2-deoxy-arabino-hexuronic acid. | the exocellular polysaccharide s-7, a heteropolysaccharide from azotobacter indicus var. myxogenes has been studied using methylation analysis, smith degradation, partial acid hydrolysis, nmr spectroscopy and mass spectrometry as the principal methods. it is concluded that the repeating unit has the following structure: [structure: see text] the absolute configuration of the deoxyhexuronic acid was deduced from 1h nmr chemical shifts and is most likely d. approximately two o-acetyl groups per re ... | 2001 | 11383898 |
| influence of the nonionic surfactant brij 35 on the bioavailability of solid and sorbed dibenzofuran. | the effect of the nonionic surfactant brij 35 on the bioavailability of solid and teflon-sorbed dibenzofuran for sphingomonas sp. strain hh19k was studied in simple model systems. growth with dibenzofuran and dibenzofuran-specific oxygen uptake in surfactant-free media and with brij 35 above the critical micelle concentration (cmc) were compared with dissolution and desorption in the absence of bacteria. brij 35 accelerated dissolution and biodegradation of solid dibenzofuran by a factor of 2. i ... | 2001 | 11393985 |
| psychrobacter proteolyticus sp. nov., a psychrotrophic, halotolerant bacterium isolated from the antarctic krill euphausia superba dana, excreting a cold-adapted metalloprotease. | an antarctic marine bacterium (strain 116) excreting an extracellular cold-adapted metalloprotease was subjected to a detailed polyphasic taxonomic investigation. strain 116 was previously isolated from the stomach of a specimen of the antarctic krill euphasia superba dana and tentatively characterized as sphingomonas paucimobilis 116. the 16s rdna sequence analysis showed that the strain is in fact related to species of the genus psychrobacter, next to psychrobacter glacincola (97.4% similarity ... | 2001 | 11403398 |
| sphingomonas pituitosa sp. nov., an exopolysaccharide-producing bacterium that secretes an unusual type of sphingan. | strain edivt, an exopolysaccharide-producing bacterium, was subjected to polyphasic characterization. the bacterium produced copious amounts of an extracellular polysaccharide, forming slimy, viscous, intensely yellow-pigmented colonies on czapek-dox (czd) agar. the culture fluids of the liquid version of czd medium were highly viscous after cultivation for 5 d. cells of strain edivt were gram-negative, catalase-positive, oxidase-negative, nonspore-forming, rod-shaped and motile. comparisons of ... | 2001 | 11411704 |
| structural analysis of a new glycosphingolipid from the lipopolysaccharide-lacking bacterium sphingomonas adhaesiva. | a new glycosphingolipid, gsl-4b, was isolated from sphingomonas adhaesiva and found to share the ceramide moiety with gsl-1 and gsl-3 from sphingomonas capsulata studied earlier [kawahara, k.; moll, h.; knirel, y. a.; seydel, u.; zähringer, u. eur. j. biochem. 2000, 267, 1837-1846]. it is heterogeneous with respect to the long-chain bases erythro-2-amino-1,3-octadecanediol (sphinganine), (13z)-erythro-2-amino-13-eicosene-1,3-diol, and (13z)-erythro-2-amino-13,14-methylene-1,3-eicosanediol which ... | 2001 | 11423114 |
| evaluation of bacteria isolated from rice for plant growth promotion and biological control of seedling disease of rice. | of 102 rhizoplane and endophytic bacteria isolated from rice roots and stems in california, 37% significantly (p < or = 0.05) inhibited the growth in vitro of two pathogens, achlya klebsiana and pythium spinosum, causing seedling disease of rice. four endophytic strains were highly effective against seedling disease in growth pouch assays, and these were identified as pseudomonas fluorescens (s3), pseudomonas tolaasii (s20), pseudomonas veronii (s21), and sphingomonas trueperi (s12) by sequencin ... | 2001 | 11718545 |
| isolation from agricultural soil and characterization of a sphingomonas sp. able to mineralize the phenylurea herbicide isoproturon. | a soil bacterium (designated strain srs2) able to metabolize the phenylurea herbicide isoproturon, 3-(4-isopropylphenyl)-1,1-dimethylurea (ipu), was isolated from a previously ipu-treated agricultural soil. based on a partial analysis of the 16s rrna gene and the cellular fatty acids, the strain was identified as a sphingomonas sp. within the alpha-subdivision of the proteobacteria. strain srs2 was able to mineralize ipu when provided as a source of carbon, nitrogen, and energy. supplementing th ... | 2001 | 11722885 |
| super-channel in bacteria: function and structure of the macromolecule import system mediated by a pit-dependent abc transporter. | in a soil isolate, sphingomonas sp. a1, the transport of a macromolecule (alginate: 27 kda) is mediated by a pit-dependent atp-binding cassette (abc) transporter. the transporter is different from other abc transporters so far analyzed in that its function is dependent on a pit, a mouth-like organ formed on the cell surface only when cells are compelled to assimilate macromolecules, and in that it allows direct import of macromolecules into cells. the abc transporter coupled with the pit, which ... | 2001 | 11731126 |
| preparation of (r)- and (s)-n-protected 3-hydroxypyrrolidines by hydroxylation with sphingomonas sp. hxn-200, a highly active, regio- and stereoselective, and easy to handle biocatalyst. | hydroxylation of n-benzylpyrrolidine 8 with resting cells of sphingomonas sp. hxn-200 gave n-benzyl-3-hydroxypyrrolidine 15 in 53% ee (s) with an activity of 5.8 u/g cdw. by changing the "docking/protecting group" in pyrrolidines, hydroxylation activity and enantioselectivity were further improved and the enantiocomplementary formation of 3-hydroxypyrrolidines was achieved: hydroxylation of n-benzoyl-, n-benzyloxycarbonyl-, n-phenoxycarbonyl-, and n-tert-butoxycarbonyl-pyrrolidines 9-12 gave the ... | 2001 | 11735520 |
| identification of protein fold and catalytic residues of gamma-hexachlorocyclohexane dehydrochlorinase lina. | gamma-hexachlorocyclohexane dehydrochlorinase (lina) is a unique dehydrochlorinase that has no homologous sequence at the amino acid-sequence level and for which the evolutionary origin is unknown. we here propose that lina is a member of a novel structural superfamily of proteins containing scytalone dehydratase, 3-oxo-delta(5)-steroid isomerase, nuclear transport factor 2, and the beta-subunit of naphthalene dioxygenase-all known structures with different functions. the catalytic and the activ ... | 2001 | 11746694 |
| sphingomonas alaskensis sp. nov., a dominant bacterium from a marine oligotrophic environment. | seven gram-negative strains, isolated in 1990 from a 10(6)-fold dilution series of seawater from resurrection bay, a deep fjord of the gulf of alaska, were identified in a polyphasic taxonomic study. analysis of 16s rdna sequences and dna-homology studies confirmed the phylogenetic position of all strains in the genus sphingomonas and further indicated that all of the strains constitute a single homogeneous genomic species, distinct from all validly described sphingomonas species. the ability to ... | 2001 | 11211276 |
| structure-specificity relationships for haloalkane dehalogenases. | a structural analysis of the substrate specificity of hydrolytic dehalogenases originating from three different bacterial isolates has been performed using the multiple computer-automated structure evaluation methodology. this methodology identifies structural fragments in substrate molecules that either activate or deactivate biological processes. the analysis presented in this contribution is based on newly measured dehalogenation data combined with data from the literature (91 substrates). th ... | 2001 | 11764149 |
| a transcriptional luxab reporter fusion responding to fluorene in sphingomonas sp. lb126 and its initial characterisation for whole-cell bioreporter purposes. | the promoter probe mini-tn5-luxab-tet was used to create a luxab transcriptional fusion responding to fluorene in the fluorene utilising bacterium sphingomonas sp. lb126. the mutant strain, named l-132, was impaired in fluorene utilisation and strongly emitted light upon addition of fluorene to the growth medium. l-132 was initially characterised and examined for its potential use as a whole-cell biosensor in the perspective of quantifying fluorene in environmental samples. activity of the repor ... | 2001 | 11766960 |
| fluorene degradation by sphingomonas sp. lb126 proceeds through protocatechuic acid: a genetic analysis. | sphingomonas sp. lb126 is able to utilize fluorene as sole source of carbon and energy. in the present study, a mutagenic vector was constructed and a "plasmid rescue" strategy was set up to isolate a 16.5-kb dna fragment containing genes required for fluorene degradation. a 14.5-kb portion of the cloned dna was sequenced revealing thirteen open reading frames. two encoded hypothetical proteins (flde and fldy) similar to transcriptional regulators and one (orf360) located on an is-like element ( ... | 2001 | 11766961 |
| streptomyces aureofaciens sporulation-specific sigma factor sigma(rpoz) directs expression of a gene encoding protein similar to hydrolases involved in degradation of the lignin-related biphenyl compounds. | a previously established method for the identification of promoters recognized by a heterologous rna polymerase holoenzyme containing a particular sigma factor was used to identify promoters dependent upon a sporulation specific sigma factor, sigma(rpoz), of streptomyces aureofaciens. three new positive dna fragments were identified, and these putative rpoz-dependent promoters, p(ren24), p(ren57), and p(ren71), contained sequences similar to the consensus sequence of flagellar and chemotaxis pro ... | 2001 | 11766963 |
| characterisation of a gene cluster involved in bacterial degradation of the cyanobacterial toxin microcystin lr. | a novel pathway for degradation of the cyanobacterial heptapeptide hepatotoxin microcystin lr was identified in a newly isolated sphingomonas sp. (bourne et al. 1996 appl. environ. microbiol. 62: 4086-4094). we now report the cloning and molecular characterisation of four genes from this sphingomonas sp. that exist on a 5.8-kb genomic fragment and encode the three hydrolytic enzymes involved in this pathway together with a putative oligopeptide transporter. the heterologously expressed degradati ... | 2001 | 11769251 |
| bacterial degradation of aromatic compounds via angular dioxygenation. | dioxygenation is one of the important initial reactions of the bacterial degradation of various aromatic compounds. aromatic compounds, such as biphenyl, toluene, and naphthalene, are dioxygenated at lateral positions of the aromatic ring resulting in the formation of cis-dihydrodiol. this "normal" type of dioxygenation is termed lateral dioxygenation. on the other hand, the analysis of the bacterial degradation of fluorene (fn) analogues, such as 9-fluorenone, dibenzofuran (df), carbazole (car) ... | 2001 | 12483604 |
| specific growth rate plays a critical role in hydrogen peroxide resistance of the marine oligotrophic ultramicrobacterium sphingomonas alaskensis strain rb2256. | the marine oligotrophic ultramicrobacterium sphingomonas alaskensis rb2256 has a physiology that is distinctly different from that of typical copiotrophic marine bacteria, such as vibrio angustum s14. this includes a high level of inherent stress resistance and the absence of starvation-induced stress resistance to hydrogen peroxide. in addition to periods of starvation in the ocean, slow, nutrient-limited growth is likely to be encountered by oligotrophic bacteria for substantial periods of tim ... | 2001 | 11229924 |
| direct electrochemistry of pentachlorophenol hydroxylase. | the direct electrochemistry of the flavin-containing monooxygenase, pentachlorophenol hydroxylase (pcph), at an edge plane graphite electrode was observed and a catalytic response, linear with concentration, was found with the substrate pentachlorophenol (pcp). | 2001 | 12240080 |
| purification and characterization of poly(aspartic acid) hydrolase from sphingomonas sp. kt-1. | poly(aspartic acid) (paa) hydrolase was purified from sphingomonas sp. kt-1 (jcm10459). the purified hydrolase degraded thermally synthesized paa to oligomers. the molecular mass of paa hydrolase was 30 kda and the isoelectric point was 8.9. the optimum values of ph and temperature for paa degradation were 10.0 and 40 degrees c, respectively. the investigation of the effect of inhibitors for the paa-degrading activities has revealed that the paa hydrolase is a serine-type hydrolase. the structur ... | 2001 | 11777387 |
| basic examinations on chemical pre-oxidation by ozone for enhancing bioremediation of phenanthrene contaminated soils. | biological treatment of polycyclic aromatic hydrocarbons (pah) has been demonstrated to be a feasible and common remediation technology which has been successfully applied to the clean-up of contaminated soils. because bioavailability of the contaminants is of great importance for a successful bioremediation, a chemical pre-oxidation step by ozone was tested to enhance the subsequent biodegradation steps. oxidation of pah by ozone should result in reaction products that have a better solubility ... | 2001 | 11778897 |
| microbial populations associated with the reduction and enhanced mobilization of arsenic in mine tailings. | microbial reduction of arsenate [as(v)] to arsenite [as(iii)] and the subsequent effects on as mobilization in contaminated mine tailings were studied under transport conditions. molecular analysis of bacterial populations and traditional isolation techniques were used in conjunction with column experiments designed to observe relationships among ph (limed vs unlimed treatments), redox potential (pt electrode), and mobilization of as. liming increased ph values from approximately 4 to 8, resulti ... | 2001 | 11783644 |
| degradation of 2,3,4,6-tetrachlorophenol at low temperature and low dioxygen concentrations by phylogenetically different groundwater and bioreactor bacteria. | effects of low temperature and low oxygen partial pressure on the occurrence and activity of 2,3,4,6-tetrachlorophenol degrading bacteria in a boreal chlorophenol contaminated groundwater and a full-scale fluidized-bed bioreactor were studied using four polychlorophenol degrading bacterial isolates of different phylogenetic backgrounds. these included an alpha-proteobacterial sphingomonas sp. strain mt1 isolated from the full-scale bioreactor and three isolates from the contaminated groundwater ... | 2001 | 11995822 |
| analysis of endophytic bacterial communities of potato by plating and denaturing gradient gel electrophoresis (dgge) of 16s rdna based pcr fragments. | the diversity of endophytic bacterial populations of potato (solanum tuberosum cv desirée) was assessed using a combination of dilution plating of plant macerates followed by isolation and characterization of isolates, and direct pcr-dgge on the basis of dna extracted from plants. the culturable endophytic bacterial communities detected in potato stem bases as well as in roots were in most cases on the order 103 to 105 cfu g?1 of fresh plant tissue. dilution plating revealed that a range of bact ... | 2001 | 12032611 |
| effects of different quinoid redox mediators on the anaerobic reduction of azo dyes by bacteria. | the addition of quinoid redox mediators to anaerobically incubated cultures of various taxonomically different bacterial species resulted in significantly increased reduction rates for the azo dye amaranth. from different quinones tested, generally anthraquinone-2-sulfonate (aqs) and lawsone (2-hydroxy-1,4-naphthoquinone) caused the highest increase in the azoreductase activities. the effects of aqs and lawsone were studied in greater detail with sphingomonas xenophaga bn6 and escherichia coli k ... | 2002 | 11999057 |
| binol-catalyzed highly enantioselective terminal alkyne additions to aromatic aldehydes. | [reaction: see text] the readily available binol ligand in combination with ti(o(i)pr)(4) was found to catalyze the highly enantioselective reaction (92-98% ee) of terminal alkynes with aromatic aldehydes that contain a variety of substituents and substitution patterns. after the preparation of the zinc acetylide reagent, the catalytic asymmetric addition to aldehydes proceeded at room temperature with excellent stereocontrol. this simple catalyst system is practical for the asymmetric synthesis ... | 2002 | 12027631 |
| practical syntheses of n-substituted 3-hydroxyazetidines and 4-hydroxypiperidines by hydroxylation with sphingomonas sp. hxn-200. | [reaction: see text] hydroxylation of n-substituted azetidines 11 and 12 and piperidines 15-19 with sphingomonas sp. hxn-200 gave 91-98% of the corresponding 3-hydroxyazetidines 13 and 14 and 4-hydroxypiperidines 20-24, respectively, with high activity and excellent regioselectivity. high yields and high product concentrations (2 g/l) were achieved with frozen/thawed cells as biocatalyst. for the first time, rehydrated lyophilized cells were successfully used for the biohydroxylation. | 2002 | 12027632 |
| xenobiotics in the environment: present and future strategies to obviate the problem of biological persistence. | sustainable chemistry aims at an improved efficiency of using natural resources which are used to meet human needs for chemical products. chemists in science and industry, have become aware of the importance to design environmentally benign chemicals. one aspect is the biological persistence and the present paper reviews work in this field focussing on the degradation of xenobiotics in the environment. different structural reasons for chemical and biological persistence are described and strateg ... | 2002 | 11792455 |
| occurrence of an alpha-galacturonosyl-ceramide in the dioxin-degrading bacterium sphingomonas wittichii. | the chemical structure of two glycosphingolipids (gsls) found in the dioxin-degrading bacterium sphingomonas wittichii strain rw1 was investigated by means of mass spectrometry and (1)h-nuclear magnetic resonance spectroscopy. one of the gsls was alpha-d-glucuronosyl-ceramide, commonly present in sphingomonas spp., and the other was proved to be alpha-d-galacturonosyl-ceramide, whose sugar configuration has not been reported before. in both gsls the ceramide portion was composed of myristic acid ... | 2002 | 12351245 |
| gellan gum biosynthesis in sphingomonas paucimobilis atcc 31461: genes, enzymes and exopolysaccharide production engineering. | the commercial gelling agent, gellan, is an extracellular polysaccharide (eps) produced by sphingomonas paucimobilis atcc 31461. in recent years, significant progress in understanding the relationship between gellan structure and properties and elucidation of the biosynthesis and engineering of this recent product of biotechnology has been made. this review focuses on recent advances in this field. emphasis is given to identification and characterization of genes and enzymes involved, or predict ... | 2002 | 12355314 |
| emendation of the genus sphingomonas yabuuchi et al. 1990 and junior objective synonymy of the species of three genera, sphingobium, novosphingobium and sphingopyxis, in conjunction with blastomonas ursincola. | the 16s rdna sequence similarities between the type strains of sphingomonas paucimobilis and 32 other sphingomonas species range from 90.2 to 99.6%. it might be possible to divide the genus into several new genera according to a dendrogram drawn from 16s rdna sequence similarity. however, the phenotypic and biochemical information needed to define clusters of strains representing distinct genera within this group of organisms was not previously available. although the cellular lipids of type str ... | 2002 | 12361250 |
| cloning and characterization of lin genes responsible for the degradation of hexachlorocyclohexane isomers by sphingomonas paucimobilis strain b90. | hexachlorocyclohexane (hch) has been used extensively against agricultural pests and in public health programs for the control of mosquitoes. commercial formulations of hch consist of a mixture of four isomers, alpha, beta, gamma, and delta. while all these isomers pose serious environmental problems, beta-hch is more problematic due to its longer persistence in the environment. we have studied the degradation of hch isomers by sphingomonas paucimobilis strain b90 and characterized the lin genes ... | 2002 | 12450824 |
| linking of microorganisms to phenanthrene metabolism in soil by analysis of (13)c-labeled cell lipids. | phenanthrene-metabolizing soil microbial communities were characterized by examining mineralization of [(14)c]phenanthrene, by most-probable-number (mpn) counting, by 16s-23s spacer dna analysis of the numerically dominant, culturable phenanthrene-degrading isolates, and by examining incorporation of [(13)c]phenanthrene-derived carbon into sterols and polar lipid fatty acids (plfas). an unpolluted agricultural soil, a roadside soil diffusely polluted with polycyclic aromatic hydrocarbons (pahs), ... | 2002 | 12450834 |
| characterization of tetrachlorohydroquinone reductive dehalogenase from sphingomonas sp. ug30. | tetrachlorohydroquinone reductive dehalogenase (pcpc) is the second of three enzymes that catalyze the initial degradation of pentachlorophenol in sphingomonas sp. ug30 and several other bacterial strains. the ug30 pcpc shares a high degree (94%) of primary sequence identity with the well-studied pcpc from sphingobium chlorophenolicum atcc 39723. significant differences, however, were observed between the two pcpc enzymes in some of their functional and kinetic properties. the temperature optimu ... | 2002 | 12459186 |
| sphingopyxis witflariensis sp. nov., isolated from activated sludge. | classification of strain w-50(t), which was isolated from a wastewater treatment plant, was investigated by a polyphasic approach. cells of strain w-50(t) were gram-negative, strictly aerobic, oxidase-positive and yellow-pigmented. ubiquinone q-10 was the main respiratory lipoquinone system and polar lipid fingerprints were characterized by the presence of a sphingoglycolipid, suggesting that strain w-50(t) belongs to the alpha-4 subclass of the proteobacteria. sequencing and comparative analyse ... | 2002 | 12508864 |
| sphingomonas melonis sp. nov., a novel pathogen that causes brown spots on yellow spanish melon fruits. | a polyphasic taxonomic study was performed on the phytopathogenic bacterial strains dapp-pg 224(t) and dapp-pg 228, which cause brown spot on yellow spanish melon (cucumis melo var. inodorus) fruits. based on the presence of glucuronosyl ceramide (sgl-1) in cellular lipids, the results of fatty acid analysis and 16s rdna sequence comparison, the strains had been identified as belonging to the genus sphingomonas and as phylogenetically related to sphingomonas mali, sphingomonas pruni and sphingom ... | 2002 | 12508872 |
| diversity of 746 heterotrophic bacteria isolated from microbial mats from ten antarctic lakes. | microbial mats, growing in antarctic lakes constitute unique and very diverse habitats. in these mats microorganisms are confronted with extreme life conditions. we isolated 746 bacterial strains from mats collected from ten lakes in the dry valleys (lakes hoare and fryxell), the vestfold hills (lakes ace, druzhby, grace, highway, pendant, organic and watts) and the larsemann hills (lake reid), using heterotrophic growth conditions. these strains were investigated by fatty acid analysis, and by ... | 2002 | 12583721 |
| a super-channel in bacteria: macromolecule uptake and depolymerization systems of sphingomonas sp. a1 with a special cell surface structure. | 2002 | 12520874 | |
| isolation and initial characterization of a bacterial consortium able to mineralize fluorobenzene. | fluorinated compounds are known to be more resistant to microbial degradation than other halogenated chemicals. a microbial consortium capable of aerobic biodegradation of fluorobenzene (fb) as the sole source of carbon and energy was isolated by selective enrichment from sediments collected in a drain near an industrial site. a combination of three microbial strains recovered from the enriched consortium was shown to be necessary for complete fb mineralization. two of the strains (f1 and f3) we ... | 2002 | 11772615 |
| novel 2,4-dichlorophenoxyacetic acid degradation genes from oligotrophic bradyrhizobium sp. strain hw13 isolated from a pristine environment. | the tfd genes of ralstonia eutropha jmp134 are the only well-characterized set of genes responsible for 2,4-dichlorophenoxyacetic acid (2,4-d) degradation among 2,4-d-degrading bacteria. a new family of 2,4-d degradation genes, cadrabkc, was cloned and characterized from bradyrhizobium sp. strain hw13, a strain that was isolated from a buried hawaiian soil that has never experienced anthropogenic chemicals. the cadr gene was inferred to encode an arac/xyls type of transcriptional regulator from ... | 2002 | 11751829 |
| molecular structure of the rhamsan-like exocellular polysaccharide rmdp17 from sphingomonas paucimobilis. | x-ray diffraction analysis of the sodium salt of the polysaccharide rmdp17, a 2-deoxy rhamsan analog, reveals that it adopts a gellan-like, half-staggered, threefold, left handed, double helix of pitch 57.4 a. the side chain of the branched polymer is hydrogen bonded to the main chain. sodium ions, linked to the carboxylate groups, promote the association of helices via water molecules. two helices of opposite polarity occupy a trigonal unit cell of dimensions a=17.6 and c=28.7 a. the packing ar ... | 2002 | 11755911 |
| cloning and characterization of linr, involved in regulation of the downstream pathway for gamma-hexachlorocyclohexane degradation in sphingomonas paucimobilis ut26. | in sphingomonas paucimobilis ut26, lind and line activities, which are responsible for the degradation of gamma-hexachlorocyclohexane, are inducibly expressed in the presence of their substrates, 2,5-dichlorohydroquinone (2,5-dchq) and chlorohydroquinone (chq). the nucleotide sequence of the 1-kb upstream region of the line gene was determined, and an open reading frame (orf) was found in divergent orientation from line. because the putative protein product of the orf showed similarity to the ly ... | 2002 | 11916699 |
| identification of mouse submaxillary gland protein in mouse saliva and its binding to mouse oral bacteria. | the mouse submaxillary gland protein (msmgp) is highly expressed in the submandibular gland of the adult mouse and rat. it shares 51% identity at the amino-acid level with a human protein, the prolactin-inducible protein (pip)/gross cystic disease fluid protein 15 (gcdfp-15), which has been found in saliva, tears, sweat, seminal plasma, submucosal glands of the lung and amniotic fluid. more recently, the human pip has been reported to bind to bacterial strains normally found in the mouth, ear ca ... | 2002 | 11922875 |
| exploring the structure and activity of haloalkane dehalogenase from sphingomonas paucimobilis ut26: evidence for product- and water-mediated inhibition. | the hydrolysis of haloalkanes to their corresponding alcohols and inorganic halides is catalyzed by alpha/beta-hydrolases called haloalkane dehalogenases. the study of haloalkane dehalogenases is vital for the development of these enzymes if they are to be utilized for bioremediation of organohalide-contaminated industrial waste. we report the kinetic and structural analysis of the haloalkane dehalogenase from sphingomonas paucimobilis ut26 (linb) in complex with each of 1,2-dichloroethane and 1 ... | 2002 | 11939779 |
| degradation of polycyclic aromatic hydrocarbons dissolved in tween 80 surfactant solutions by sphingomonas paucimobilis epa 505. | the degradation rates of mixtures of pyrene (pyr), fluoranthene (fla), and phenanthrene (phe) by sphingomonas paucimobilis epa 505 were measured in the presence of the nonionic surfactant tween 80. for strain epa 505, fla and phe are growth substrates, while pyr is not. linear degradation rates ranging from 0.05 to 2.2 mg x l(-1) x h(-1) were observed for fla, pyr, and phe at approximately 10(7) colony-forming units (cfu)/ml. at lower biomass, pyr degradation exhibited lognormal degradation. the ... | 2002 | 11958568 |
| isolation and characterization of dibenzofuran-degrading bacteria. | two bacterial strains capable of utilizing dibenzofuran (df) as a sole carbon source were isolated from soil samples of reclaimed land. the strains designated hl1 and hl7 were identified as klebsiella sp. and sphingomonas sp., respectively, on the basis of biochemical characteristics and the sequences of the 16s ribosomal dna. sphingomonas sp. strain hl7 degraded non-, mono- and also dichlorinated df and dibenzo-p-dioxin (dd). klebsiella sp. strain hl1 was able to degrade non- and monochlorinate ... | 2002 | 11959434 |
| extracellular polysaccharides of rhodococcus rhodochrous s-2 stimulate the degradation of aromatic components in crude oil by indigenous marine bacteria. | rhodococcus rhodochrous s-2 produces extracellular polysaccharides (s-2 eps) containing d-glucose, d-galactose, d-mannose, d-glucuronic acid, and lipids, which is important to the tolerance of this strain to an aromatic fraction of (af) arabian light crude oil (n. iwabuchi, n. sunairi, h. anzai, m. nakajima, and s. harayama, appl. environ. microbiol. 66:5073-5077, 2000). in the present study, we examined the effects of s-2 eps on the growth of indigenous marine bacteria on af. indigenous bacteri ... | 2002 | 11976106 |
| biotransformation of 2,7-dichloro- and 1,2,3,4-tetrachlorodibenzo-p-dioxin by sphingomonas wittichii rw1. | aerobic biotransformation of the diaryl ethers 2,7-dichlorodibenzo-p-dioxin and 1,2,3,4-tetrachlorodibenzo-p-dioxin by the dibenzo-p-dioxin-utilizing strain sphingomonas wittichii rw1, producing corresponding metabolites, was demonstrated for the first time. our strain transformed 2,7-dichlorodibenzo-p-dioxin, yielding 4-chlorocatechol, and 1,2,3,4-tetrachlorodibenzo-p-dioxin, producing 3,4,5,6-tetrachlorocatechol and 2-methoxy-3,4,5,6-tetrachlorophenol; all of these compounds were unequivocally ... | 2002 | 11976140 |
| characterization of sphingomonas sp. ant 17, an aromatic hydrocarbon-degrading bacterium isolated from antarctic soil. | sphingomonas sp. strain ant 17 was isolated from fuel-contaminated soil collected at scott base, ross island, antarctica. we anticipated that ant 17 would be a good model organism for studying cold climate bioremediation, and therefore determined its biodegradation capabilities and tolerance of potentially growth-limiting environmental conditions. sphingomonas sp. ant 17 degrades the aromatic fraction of several different crude oils, jet fuel, and diesel fuel at low temperatures and without nutr ... | 2002 | 11984628 |
| a kinetic model for surfactant inhibition of pentachlorophenol biodegradation. | a kinetic model is used to describe the effect of the nonionic surfactant tergitol np-10 (tnp10) on pentachlorophenol (pcp) biodegradation by sphingomonas chlorophenolica sp. strain ra2. different initial biomass to initial substrate ratios ranging from 13 to 418 were tested with 23 tnp10 concentrations ranging from 0 to 1500 mg/l. tests were also conducted at 10 degrees c and 20 degrees c. no pcp biodegradation inhibition was observed at concentrations below the critical micelle concentration ( ... | 2002 | 11992526 |
| enzymatic reaction of hydrogen peroxide-dependent peroxygenase cytochrome p450s: kinetic deuterium isotope effects and analyses by resonance raman spectroscopy. | cytochromes p450sp(alpha) (cyp152b1) and p450bs(beta) (cyp152a1), which are isolated from sphingomonas paucimobilis and bacillus subtilis, respectively, belong to the p450 superfamily, but catalyze hydroxylation reactions, in which an oxygen atom from h2o2 is efficiently introduced into fatty acids (e.g., myristic acid). p450sp(alpha) produces the alpha-hydroxylated (alpha-oh) products at 100%, while p450bs(beta) produces alpha- and beta-hydroxylated (beta-oh) products at 33 and 67%, respectivel ... | 2002 | 11827534 |
| aerobic and facultatively anaerobic cellulolytic bacteria from the gut of the termite zootermopsis angusticollis. | to demonstrate the occurrence of cellulolytic bacteria in the termite zootermopsis angusticollis. | 2002 | 11849325 |
| employment of the human estrogen receptor beta ligand-binding domain and co-activator src1 nuclear receptor-binding domain for the construction of a yeast two-hybrid detection system for endocrine disrupters. | to screen a wide variety of chemicals for endocrine disrupters, and to develop an effective microbial degradation system for them, a good system is needed for the rapid and accurate evaluation of the endocrine-disrupting activities of suspected chemicals and their degradation products. we constructed two-hybrid systems that co-express the gal4p dna binding domain/ligand-binding domain of human estrogen receptor (her) alpha or beta and the gal4p transactivation domain/nuclear receptor-binding dom ... | 2002 | 11872169 |
| molecular detection and diversity of polycyclic aromatic hydrocarbon-degrading bacteria isolated from geographically diverse sites. | nineteen polycyclic aromatic hydrocarbon (pah)-degrading bacteria were isolated from environmental samples in kuwait, indonesia, thailand, and japan by enrichment with either naphthalene or phenanthrene as a sole carbon source. sequence analyses of the 16-s rrna gene indicated that at least seven genera (ralstonia, sphingomonas, burkholderia, pseudomonas, comamonas, flavobacterium, and bacillus) were present in this collection. determination of the ability of the isolates to use pah and its pres ... | 2002 | 11876413 |
| crystal structure of algq2, a macromolecule (alginate)-binding protein of sphingomonas sp. a1 at 2.0a resolution. | sphingomonas sp. a1 possesses a high molecular mass (average 25,700 da) alginate uptake system mediated by a novel pit-dependent abc transporter. the x-ray crystallographic structure of algq2 (57,200 da), an alginate-binding protein in the system, was determined by the multiple isomorphous replacement method and refined at 2.0 a resolution with a final r-factor of 18.3% for 15 to 2.0 a resolution data. the refined structure of algq2 was comprised of 492 amino acid residues, 172 water molecules, ... | 2002 | 11884143 |
| recurrent sphingomonas paucimobilis -bacteraemia associated with a multi-bacterial water-borne epidemic among neutropenic patients. | a cluster of septicaemias due to several water-related species occurred in a haematological unit of a university hospital. in recurrent septicaemias of a leukaemic patient caused by sphingomonas paucimobilis, genotyping of the blood isolates by use of random amplified polymorphic dna-analysis verified the presence of two distinct s. paucimobilis strains during two of the separate episodes. a strain of s. paucimobilis identical to one of the patient's was isolated from tap water collected in the ... | 2002 | 11886195 |
| nonionic surfactant effects on pentachlorophenol biodegradation. | several potential mechanisms of surfactant-induced inhibition of pentachlorophenol (pcp) biodegradation were tested using a pure bacterial culture of sphingomonas chlorophenolicum sp. strain ra2. pcp degradation, glucose degradation, and oxygen uptake during endogenous conditions and during glucose degradation were measured for batch systems in the presence of the nonionic surfactant tergitol np-10 (tnp10). tnp10 did not exert toxicity on ra2 as measured by dissolved oxygen uptake rates under en ... | 2002 | 11902780 |
| recycle use of sphingomonas sp. cdh-7 cells for continuous degradation of carbazole in the presence of mgcl2. | carbazole (ca) is a heterocyclic nitrogen compound contained in the crude petroleum oil and recalcitrant to removal through the refinery processes. for development of the efficient ca-degradation bioprocess, conditions for the recycle use of sphingomonas sp. cdh-7 resting cells were examined. when the resting cells (o.d.(660) 3.3) were shaken in 50 m m k2hpo4-kh2po4 buffer (ph 7.0) containing ca 1000 mg/l, ca 880 mg/l was degraded within 3 h, but thereafter the activity decreased markedly. howev ... | 2002 | 11910494 |
| prevalent bacterial species and novel phylotypes in advanced noma lesions. | the purpose of this study was to determine the bacterial diversity in advanced noma lesions using culture-independent molecular methods. 16s ribosomal dna bacterial genes from dna isolated from advanced noma lesions of four nigerian children were pcr amplified with universally conserved primers and spirochetal selective primers and cloned into escherichia coli. partial 16s rrna sequences of approximately 500 bases from 212 cloned inserts were used initially to determine species identity or close ... | 2002 | 12037085 |
| microbiota of periapical lesions refractory to endodontic therapy. | the periapical microbiota of 36 teeth with refractory apical periodontitis was investigated. none of the teeth had responded to conventional endodontic or long-term (> 6 months), calcium-hydroxide treatment. eight patients had received antibiotics systemically. after anaerobic culture, a total of 148 microbial strains were detected among 67 microbial species. one of the 36 lesions was culture-negative. approximately half (51.0%) of the bacterial strains were anaerobic. gram-positive species cons ... | 2002 | 12043869 |
| sphingomonas sp. strain ka1, carrying a carbazole dioxygenase gene homologue, degrades chlorinated dibenzo-p-dioxins in soil. | hybridization analysis showed that a newly isolated carbazole (car)-degrading bacterium sphingomonas sp. strain ka1 did not possess the gene encoding the terminal oxygenase component (caraa) of car 1,9a-dioxygenase at high homology (more than 90% identity) to that of another car-degrader, pseudomonas resinovorans strain ca10. however, pcr experiments using the primers for amplifying the internal fragment of the caraa gene (810 bp for strain ca10) showed that a pcr product of unexpected size (110 ... | 2002 | 12052549 |
| correction of the connecting vowel and gender of the specific epithet in the name sphingomonas macrogoltabidus takeuchi et al. 1993 to sphingomonas macrogolitabida. | in accordance with the bacteriological code (1990 revision), the connecting vowel and gender of the specific epithet macrogoltabidus in combination with the generic name sphingomonas must be -i- and the ending must be changed to -a to agree with the gender of the generic name, respectively. thus sphingomonas macroboltabidus takeuchi et al. 1993 should be sphingomonas macrogolitabida corrig. takeuchi et al. 1993. | 2002 | 12054221 |
| microbial diseases of corals and global warming. | coral bleaching and other diseases of corals have increased dramatically during the last few decades. as outbreaks of these diseases are highly correlated with increased sea-water temperature, one of the consequences of global warming will probably be mass destruction of coral reefs. the causative agent(s) of a few of these diseases have been reported: bleaching of oculina patagonica by vibrio shiloi; black band disease by a microbial consortium; sea-fan disease (aspergillosis) by aspergillus sy ... | 2002 | 12071977 |
| degradation of phenanthrene, methylphenanthrenes and dibenzothiophene by a sphingomonas strain 2mpii. | strain sphingomonassp. (2mpii), isolated from marine sediment, was able to utilize phenanthrene (p) or 2-methylphenanthrene (2mp) as the sole carbon source. however, 9-methylphenanthrene (9mp) and dibenzothiophene (dbt) were weakly degraded. the degradation rates of 9mp and dbt increased in the presence of 2mp, whilst the degradation rate of 2mp increased in the presence of 9mp. however, the presence of dbt inhibited the degradation of 2mp. dbt sulfone, a dbt metabolite, was not assimilated by t ... | 2002 | 12073136 |
| aerobic degradation of 2,4,6-trichlorophenol by a microbial consortium - selection and characterization of microbial consortium. | a microbial consortium that efficiently degrades 2,4,6-tcp (2,4,6-trichlorophenol), as the sole source of carbon and energy under aerobic conditions was selected from municipal activated sludge. six bacterial strains, designated s(1), s(2), s(3), s(4), s(5) and s(6), were isolated from the selected consortium and five were identified as sphingomonas paucimobilis (s(2), s(3)), burkholderia cepacia(s(4)), chryseomonas luteola (s(5)) and vibrio metschnikovii (s(6)). after prolonged cultivation foll ... | 2002 | 12073141 |
| growth in coculture stimulates metabolism of the phenylurea herbicide isoproturon by sphingomonas sp. strain srs2. | metabolism of the phenylurea herbicide isoproturon by sphingomonas sp. strain srs2 was significantly enhanced when the strain was grown in coculture with a soil bacterium (designated strain srs1). both members of this consortium were isolated from a highly enriched isoproturon-degrading culture derived from an agricultural soil previously treated regularly with the herbicide. based on analysis of the 16s rrna gene, strain srs1 was assigned to the beta-subdivision of the proteobacteria and probab ... | 2002 | 12089031 |
| use of a two-phase partitioning bioreactor for degrading polycyclic aromatic hydrocarbons by a sphingomonas sp. | a two-phase partitioning bioreactor (tppb) utilizing the bacterium sphingomonas aromaticivorans b0695 was used to degrade four low molecular weight (lmw) polycyclic aromatic hydrocarbons (pahs). the tppb concept is based on the use of a biocompatible, immiscible organic solvent in which high concentrations of recalcitrant substrates are dissolved. these substances partition into the cell-containing aqueous phase at rates determined by the metabolic activity of the cells. experiments showed that ... | 2002 | 12111172 |