| self-transmissible mercury resistance plasmids with gene-mobilizing capacity in soil bacterial populations: influence of wheat roots and mercury addition. | a set of mercury resistance plasmids was obtained from wheat rhizosphere soil amended or not amended with mercuric chloride via exogenous plasmid isolation by using pseudomonas fluorescens r2f, pseudomonas putida uwc1, and enterobacter cloacae be1 as recipient strains. the isolation frequencies were highest from soil amended with high levels of mercury, and the isolation frequencies from unamended soil were low. with p. putida uwc1 as the recipient, the isolation frequency was significantly enha ... | 1998 | 9546155 |
| 19f nuclear magnetic resonance as a tool to investigate microbial degradation of fluorophenols to fluorocatechols and fluoromuconates. | a method was developed to study the biodegradation and oxidative biodehalogenation of fluorinated phenols by 19f nuclear magnetic resonance (nmr). characterization of the 19f nmr spectra of metabolite profiles of a series of fluorophenols, converted by purified phenol hydroxylase, catechol 1,2-dioxygenase, and/or by the yeast-like fungus exophiala jeanselmei, provided possibilities for identification of the 19f nmr chemical shift values of fluorinated catechol and muconate metabolites. as an exa ... | 1998 | 9546160 |
| grazing of tetrahymena sp. on adhered bacteria in percolated columns monitored by in situ hybridization with fluorescent oligonucleotide probes. | predation of attached pseudomonas putida mt2 by the small ciliate tetrahymena sp. was investigated with a percolated column system. grazing rates were examined under static and dynamic conditions and were compared to grazing rates in batch systems containing suspended prey. the prey densities were 2 x 10(8) bacteria per ml of pore space and 2 x 10(8) bacteria per ml of suspension, respectively. postingestion in situ hybridization of bacteria with fluorescent oligonucleotide probes was used to qu ... | 1998 | 9546161 |
| biodegradation of metal-edta complexes by an enriched microbial population. | a mixed culture utilizing edta as the sole carbon source was isolated from a mixed inoculum of water from the river mersey (united kingdom) and sludge from an industrial effluent treatment plant. fourteen component organisms were isolated from the culture, including representatives of the genera methylobacterium, variovorax, enterobacter, aureobacterium, and bacillus. the mixed culture biodegraded metal-edta complexes slowly; the biodegradability was in the order fe > cu > co > ni > cd. by incor ... | 1998 | 9546167 |
| development of a direct in situ pcr method for detection of specific bacteria in natural environments. | we applied hnpp (2-hydroxy-3-naphthoic acid-2'-phenylanilide phosphate) to direct in situ pcr for the routine detection of specific bacterial cells at the single-cell level. pcr was performed on glass slides with digoxigenin-labeled dutp. the digoxigenin-labeled pcr products were detected with alkaline phosphatase-labeled antidigoxigenin antibody and hnpp which was combined with fast red tr. a bright red fluorescent signal was produced from conversion to hnp (dephosphorylated form) by alkaline p ... | 1998 | 9546190 |
| ntn genes determining the early steps in the divergent catabolism of 4-nitrotoluene and toluene in pseudomonas sp. strain tw3. | pseudomonas sp. strain tw3 is able to oxidatively metabolize 4-nitrotoluene and toluene via a route analogous to the upper pathway of the tol plasmids. we report the sequence and organization of five genes, ntnwcmab*, which are very similar to and in the same order as the xyl operon of tol plasmid pww0 and present evidence that they encode enzymes which are expressed during growth on both 4-nitrotoluene and toluene and are responsible for their oxidation to 4-nitrobenzoate and benzoate, respecti ... | 1998 | 9555884 |
| availability of o2 as a substrate in the cytoplasm of bacteria under aerobic and microaerobic conditions. | the growth rates of pseudomonas putida kt2442 and mt-2 on benzoate, 4-hydroxybenzoate, or 4-methylbenzoate showed an exponential decrease with decreasing oxygen tensions (partial o2 tension [po2] values). the oxygen tensions resulting in half-maximal growth rates were in the range of 7 to 8 mbar of o2 (corresponding to 7 to 8 microm o2) (1 bar = 10(5) pa) for aromatic compounds, compared to 1 to 2 mbar for nonaromatic compounds like glucose or succinate. the decrease in the growth rates coincide ... | 1998 | 9555896 |
| the tfdk gene product facilitates uptake of 2,4-dichlorophenoxyacetate by ralstonia eutropha jmp134(pjp4). | uptake of 2,4-dichlorophenoxyacetate (2,4-d) by ralstonia eutropha jmp134(pjp4) was studied and shown to be an energy-dependent process. the uptake system was inducible with 2,4-d and followed saturation kinetics in a concentration range of up to 60 microm, implying the involvement of a protein in the transport process. we identified an open reading frame on plasmid pjp4, which was designated tfdk, whose translation product tfdk was highly hydrophobic and showed resemblance to transport proteins ... | 1998 | 9555911 |
| overexpression, purification, and characterization of the cloned metallo-beta-lactamase l1 from stenotrophomonas maltophilia. | the metallo-beta-lactamase l1 from stenotrophomonas maltophilia was cloned, overexpressed, and characterized by spectrometric and biochemical techniques. results of metal analyses were consistent with the cloned enzyme having 2 mol of tightly bound zn(ii) per monomer. gel filtration chromatography demonstrated that the cloned enzyme exists as a tightly held tetramer with a molecular mass of ca. 115 kda, and matrix-assisted laser desorption ionization and time-of-flight mass spectrometry indicate ... | 1998 | 9559809 |
| alginate lyase promotes diffusion of aminoglycosides through the extracellular polysaccharide of mucoid pseudomonas aeruginosa. | we demonstrated that a 2% suspension of pseudomonas aeruginosa alginate completely blocked the diffusion of gentamicin and tobramycin, but not that of carbenicillin, illustrating how alginate production can help protect p. aeruginosa growing within alginate microcolonies in patients with cystic fibrosis (cf) from the effects of aminoglycosides. this aminoglycoside diffusion barrier was degraded with a semipurified preparation of p. aeruginosa alginate lyase, suggesting that this enzyme deserves ... | 1998 | 9559826 |
| a novel phenol hydroxylase and catechol 2,3-dioxygenase from the thermophilic bacillus thermoleovorans strain a2: nucleotide sequence and analysis of the genes. | the new thermophilic bacillus thermoleovorans strain a2 degrades phenol and cresols via the meta cleavage pathway. the first two enzymes involved in this process, the phenol hydroxylase and catechol 2,3-dioxygenase, encoded by the phea and pheb genes respectively, were cloned and sequenced. the deduced amino acid sequence of phea contains 524 amino acids with a theoretical m(r) of 59,602 da and displays less than 10% amino acid identity to known phenol hydroxylases. the greatest amino acid ident ... | 1998 | 9561730 |
| is1491 from pseudomonas alcaligenes ncib 9867: characterization and distribution among pseudomonas species. | a new insertion sequence, is1491, has been cloned and sequenced. the 2489-bp is1491 was isolated from a pseudomonas alcaligenes ncib 9867 (strain p25x) 4.8-kb psti chromosomal fragment. is1491 is flanked by an imperfect inverted repeat of 23 bp and carries two overlapping open reading frames, orf1 and orf2. both orf1 and orf2 displayed homology to the ista-like and istb-like transposases encoded by the is21 family of insertion sequences, which include two is elements previously isolated from p. ... | 1998 | 9571135 |
| modular fluorescent-labeled siderophore analogues. | biomimetic analogues 1 of the microbial siderophore (iron carrier) ferrichrome were labeled via piperazine with various fluorescent markers at a site not interfering with iron binding or receptor recognition (compounds 10-12). these iron carriers were built from a tetrahedral carbon symmetrically extended with three strands, each containing an amino acid (g = glycyl, a = alanyl, l = leucyl and p = phenylalanyl) and terminated by a hydroxamic acid, which together define an octahedral iron-binding ... | 1998 | 9572892 |
| a gene system for glucitol transport and metabolism in clostridium beijerinckii ncimb 8052. | the gutd gene of clostridium beijerinckii ncimb 8052 encoding glucitol 6-phosphate dehydrogenase was cloned on a 5.7-kbp chromosomal dna fragment by complementing an escherichia coli gutd mutant strain and selecting for growth on glucitol. five open reading frames (orfs) in the order guta1 guta2 orfx gutb gutd were identified in a 4.0-kbp region of the cloned dna. the deduced products of four of these orfs were homologous to components of the glucitol phosphotransferase system (pts) and glucitol ... | 1998 | 9572925 |
| two new mycobacterium strains and their role in toluene degradation in a contaminated stream. | two toluene-degrading strains, t103 and t104, were isolated from rock surface biomass in a freshwater stream contaminated with toluene. the strains exhibit different capacities for degradation of toluene and other aromatic compounds and have characteristics of the genus mycobacterium. both are aerobic, rod-shaped, gram-positive, nonmotile, and acid-alcohol fast and produce yellow pigments. they have mainly straight-chain saturated and monounsaturated fatty acids with 10 to 20 carbon atoms and la ... | 1998 | 9572941 |
| a mixed culture recovery method indicates that enteric bacteria do not enter the viable but nonculturable state. | a new method, called the mixed culture recovery (mcr) method, has been developed to determine whether recovery of culturable bacterial cells from a population of largely nonculturable cells is due to resuscitation of the nonculturable cells from a viable but nonculturable state or simply to growth of residual culturable cells. the mcr method addresses this issue in that it involves the mixing of two easily distinguishable strains (e.g., lactose positive and negative) in such a way that large num ... | 1998 | 9572945 |
| use of inducible feedback-resistant n-acetylglutamate synthetase (arga) genes for enhanced arginine biosynthesis by genetically engineered escherichia coli k-12 strains. | the goal of this work was to construct escherichia coli strains capable of enhanced arginine production. the arginine biosynthetic capacity of previously engineered e. coli strains with a derepressed arginine regulon was limited by the availability of endogenous ornithine (m. tuchman, b. s. rajagopal, m. t. mccann, and m. h. malamy, appl. environ. microbiol. 63:33-38, 1997). ornithine biosynthesis is limited due to feedback inhibition by arginine of n-acetylglutamate synthetase (nags), the produ ... | 1998 | 9572954 |
| oxidation of methyl-substituted naphthalenes: pathways in a versatile sphingomonas paucimobilis strain | aromatic compounds with alkyl substituents are abundant in fossil fuels. these compounds become important environmental sources of soluble toxic products, developmental inhibitors, etc. principally through biological activities. to assess the effect of methyl substitution on the completeness of mineralization and accumulation of pathway products, an isolate from a phenanthrene enrichment culture, sphingomonas paucimobilis 2322, was used. washed cell suspensions containing cells grown on 2,6-dime ... | 1998 | 9572967 |
| effect of bacterial distribution and activity on conjugal gene transfer on the phylloplane of the bush bean (phaseolus vulgaris). | conjugal plasmid transfer was examined on the phylloplane of bean (phaseolus vulgaris) and related to the spatial distribution pattern and metabolic activity of the bacteria. the donor (pseudomonas putida kt2442) harbored a derivative of the tol plasmid, which conferred kanamycin resistance and had the gfp gene inserted downstream of a lac promoter. a chromosomal insertion of laciq prevented expression of the gfp gene. the recipient (p. putida kt2440) had a chromosomal tetracycline resistance ma ... | 1998 | 9572970 |
| structures of homologous composite transposons carrying cbaabc genes from europe and north america. | is1071 is a class ii transposable element carrying a tnpa gene related to the transposase genes of the tn3 family. copies of is1071 that are conserved with more than 99% nucleotide sequence identity have been found as direct repeats flanking a remarkable variety of catabolic gene sequences worldwide. the sequences of chlorobenzoate catabolic transposons found on pbrc60 (tn5271) in niagara falls, n.y., and on pcpe3 in bologna, italy, show that these transposons were formed from highly homologous ... | 1998 | 9572977 |
| burkholderia cepacia produces a hemolysin that is capable of inducing apoptosis and degranulation of mammalian phagocytes. | burkholderia cepacia is an opportunistic pathogen that has become a major threat to individuals with cystic fibrosis (cf). in approximately 20% of patients, pulmonary colonization with b. cepacia leads to cepacia syndrome, a fatal fulminating pneumonia sometimes associated with septicemia. it has been reported that culture filtrates of clinically derived strains of b. cepacia are hemolytic. in this study, we have characterized a factor which contributes to this hemolytic activity and is secreted ... | 1998 | 9573086 |
| cloning of genes coding for the three subunits of thiocyanate hydrolase of thiobacillus thioparus thi 115 and their evolutionary relationships to nitrile hydratase. | thiocyanate hydrolase is a newly found enzyme from thiobacillus thioparus thi 115 that converts thiocyanate to carbonyl sulfide and ammonia (y. katayama, y. narahara, y. inoue, f. amano, t. kanagawa, and h. kuraishi, j. biol. chem. 267:9170-9175, 1992). we have cloned and sequenced the scn genes that encode the three subunits of the enzyme. the scnb, scna, and scnc genes, arrayed in this order, contained open reading frames encoding sequences of 157, 126, and 243 amino acid residues, respectivel ... | 1998 | 9573140 |
| regulation of the carnitine pathway in escherichia coli: investigation of the cai-fix divergent promoter region. | the divergent structural operons caitabcde and fixabcx of escherichia coli are required for anaerobic carnitine metabolism. transcriptional monocopy lacz fusion studies showed that both operons are coexpressed during anaerobic growth in the presence of carnitine, respond to common environmental stimuli (like glucose and nitrate), and are modulated positively by the same general regulators, crp and fnr, and negatively by h-ns. overproduction of the caif specific regulatory protein mediating the c ... | 1998 | 9573142 |
| mutational analysis of the phosphate-binding loop of rhizobium meliloti dctd, a sigma54-dependent activator. | the phosphate-binding loop of sigma54-dependent activators is thought to participate in atp binding and/or hydrolysis. alanine substitutions at positions 3, 4, 6, 7, and 8 of this motif in rhizobium meliloti dctd disrupted transcriptional activation and atp hydrolysis. interestingly, substitution of alanine at position 7 also affected dna binding. | 1998 | 9573172 |
| regulation of lactose utilization genes in staphylococcus xylosus. | the lactose utilization genes of staphylococcus xylosus have been isolated and characterized. the system is comprised of two structural genes, lacp and lach, encoding the lactose permease and the beta-galactosidase proteins, respectively, and a regulatory gene, lacr, coding for an activator of the arac/xyls family. the lactose utilization genes are divergently arranged, the lacph genes being opposite to lacr. the lacph genes are cotranscribed from one promoter in front of lacp, whereas lacr is t ... | 1998 | 9573174 |
| metalloadsorption by escherichia coli cells displaying yeast and mammalian metallothioneins anchored to the outer membrane protein lamb. | yeast (cup1) and mammalian (hmt-1a) metallothioneins (mts) have been efficiently expressed in escherichia coli as fusions to the outer membrane protein lamb. a 65-amino-acid sequence from the cup1 protein of saccharomyces cerevisiae (yeast [y] mt) was genetically inserted in permissive site 153 of the lamb sequence, which faces the outer medium. a second lamb fusion at position 153 was created with 66 amino acids recruited from the form of human (h) mt that is predominant in the adipose tissue, ... | 1998 | 9573175 |
| 2-ketocyclohexanecarboxyl coenzyme a hydrolase, the ring cleavage enzyme required for anaerobic benzoate degradation by rhodopseudomonas palustris. | 2-ketocyclohexanecarboxyl coenzyme a (2-ketochc-coa) hydrolase has been proposed to catalyze an unusual hydrolytic ring cleavage reaction as the last unique step in the pathway of anaerobic benzoate degradation by bacteria. this enzyme was purified from the phototrophic bacterium rhodopseudomonas palustris by sequential q-sepharose, phenyl-sepharose, gel filtration, and hydroxyapatite chromatography. the sequence of the 25 n-terminal amino acids of the purified hydrolase was identical to the ded ... | 1998 | 9573182 |
| substrate specificities of hybrid naphthalene and 2,4-dinitrotoluene dioxygenase enzyme systems. | bacterial three-component dioxygenase systems consist of reductase and ferredoxin components which transfer electrons from nad(p)h to a terminal oxygenase. in most cases, the oxygenase consists of two different subunits (alpha and beta). to assess the contributions of the alpha and beta subunits of the oxygenase to substrate specificity, hybrid dioxygenase enzymes were formed by coexpressing genes from two compatible plasmids in escherichia coli. the activities of hybrid naphthalene and 2,4-dini ... | 1998 | 9573183 |
| transcriptional repression mediated by lysr-type regulator catr bound at multiple binding sites. | the catbca operon of pseudomonas putida encodes enzymes involved in the catabolism of benzoate. transcription of this operon requires the lysr-type transcriptional regulator catr and an inducer molecule, cis,cis-muconate. previous gel shift assays and dnase i footprinting have demonstrated that catr occupies two adjacent sites proximal to the catbca promoter in the presence of the inducer. we report the presence of an additional binding site for catr downstream of the catbca promoter within the ... | 1998 | 9573187 |
| regulation of benzoate degradation in acinetobacter sp. strain adp1 by benm, a lysr-type transcriptional activator. | in acinetobacter sp. strain adp1, benzoate degradation requires the ben genes for converting benzoate to catechol and the cat genes for degrading catechol. here we describe a novel transcriptional activator, benm, that regulates the chromosomal ben and cat genes. benm is homologous to catm, a lysr-type transcriptional activator of the cat genes. unusual regulatory features of this system include the abilities of both benm and catm to recognize the same inducer, cis,cis-muconate, and to regulate ... | 1998 | 9573203 |
| a novel 2-aminomuconate deaminase in the nitrobenzene degradation pathway of pseudomonas pseudoalcaligenes js45. | 2-aminomuconate, an intermediate in the metabolism of tryptophan in mammals, is also an intermediate in the biodegradation of nitrobenzene by pseudomonas pseudoalcaligenes js45. strain js45 hydrolyzes 2-aminomuconate to 4-oxalocrotonic acid, with the release of ammonia, which serves as the nitrogen source for growth of the microorganism. as an initial step in studying the novel deamination mechanism, we report here the purification and some properties of 2-aminomuconate deaminase. the purified e ... | 1998 | 9573204 |
| a gene cluster encoding steps in conversion of naphthalene to gentisate in pseudomonas sp. strain u2. | pseudomonas sp. strain u2 was isolated from oil-contaminated soil in venezuela by selective enrichment on naphthalene as the sole carbon source. the genes for naphthalene dioxygenase were cloned from the plasmid dna of strain u2 on an 8.3-kb bamhi fragment. the genes for the naphthalene dioxygenase genes nagaa (for ferredoxin reductase), nagab (for ferredoxin), and nagac and nagad (for the large and small subunits of dioxygenase, respectively) were located by southern hybridizations and by nucle ... | 1998 | 9573207 |
| fluorescent pseudomonad pyoverdines bind and oxidize ferrous ion. | major pyoverdines from pseudomonas fluorescens 2-79 (pf-b), p. aeruginosa atcc 15692 (pa-c), and p. putida atcc 12633 (pp-c) were examined by absorption and fluorescence spectroscopic techniques to investigate the interaction between ferrous ion and the pyoverdine ligand. at physiological ph, ferrous ion quenched the fluorescence of all three pyoverdines much faster than ferric ion did. also, increased absorbance at 460 nm was observed to be much faster for fe2+ -pyoverdine than for fe3+ -pyover ... | 1998 | 9575133 |
| defense activation and enhanced pathogen tolerance induced by h2o2 in transgenic tobacco. | transgenic tobacco deficient in the h2o2-removing enzyme catalase (cat1as) was used as an inducible and noninvasive system to study the role of h2o2 as an activator of pathogenesis-related (pr) proteins in plants. excess h2o2 in cat1as plants was generated by simply increasing light intensities. sustained exposure of cat1as plants to excess h2o2 provoked tissue damage, stimulated salicylic acid and ethylene production, and induced the expression of acidic and basic pr proteins with a timing and ... | 1998 | 9576968 |
| genetics of ferulic acid bioconversion to protocatechuic acid in plant-growth-promoting pseudomonas putida wcs358. | transposon tn5 genomic mutants of plant-growth-promoting pseudomonas putida strain wcs358 have been isolated which no longer utilize ferulic and coumaric acids as sole sources of carbon and energy. genetic studies confirmed previous biochemical data showing that ferulic acid is degraded via vanillic acid, and coumaric acid via hydroxybenzoic acid. the genes involved in these enzymic steps were cloned and characterized. two proteins designated fca (26.5 kda) and vdh (50.3 kda) were identified as ... | 1998 | 9579070 |
| characterization of bradyrhizobium japonicum pcabdc genes involved in 4-hydroxybenzoate degradation. | the pca structural genes encode enzymes that participate in the conversion of protocatechuate to succinate and acetylcoenzyme a. a 3. 05-kb region of the bradyrhizobium japonicum strain usda110 genome has been characterized, which contains the pcab, pcad and pcac genes. the predicted protein sequences of the three genes have extensive homologies with beta-carboxy-cis,cis-muconate cycloisomerase (pcab), beta-ketodiapate enol-lactone hydrolase (pcad), and gamma-carboxymuconolactone decarboxylase ( ... | 1998 | 9582432 |
| h2-m3 restricted presentation of a listeria-derived leader peptide. | protective immunity to infection by many intracellular pathogens requires recognition by cytotoxic t lymphocytes (ctls) of antigens presented on major histocompatibility complex (mhc) class i molecules. to be presented for recognition by pathogen-specific ctls, these antigens must gain access to the host cell class i processing pathway. in the case of intracellular bacterial pathogens, the majority of bacterial proteins are retained within the bacterial membrane and therefore remain inaccessible ... | 1998 | 9584149 |
| reductive and oxidative half-reactions of morphinone reductase from pseudomonas putida m10: a kinetic and thermodynamic analysis. | the reaction of morphinone reductase (mr) with the physiological reductant nadh and the oxidizing substrate codeinone has been studied by multiple and single wavelength stopped-flow spectroscopy. reduction of the enzyme with nadh proceeds in two kinetically resolvable steps. in the first step, the oxidized enzyme forms a charge-transfer intermediate with nadh. the charge-transfer complex is characterized by an increase in absorbance at long wavelength (540 to 650 nm), and its rate of formation i ... | 1998 | 9585575 |
| hypothermia predisposing to pseudomonas putida sepsis in a child with panhypopituitarism. | a 14-year-old boy presented with a 1-week history of hypothermia and obtundation. his medical history included surgical resection of craniopharyngioma with postoperative visual impairment and panhypopituitarism. the patient's rectal temperature remained persistently lower than 35 degrees c during the first 3 days of hospitalization. his blood pressure was 90/56 mmhg on admission. the peripheral blood leukocyte count was 2.7 x 10(10)/l with 18% neutrophils, 19% band forms, 44% metamyelocytes, 3% ... | 1998 | 9585682 |
| a 7.6kb dna region from streptomyces kasugaensis m338-m1 includes some genes responsible for kasugamycin biosynthesis. | a 7.6kb psti-kpni dna fragment including a sequence highly similar to kasugamycin acetyltransferase gene (kac) was isolated from streptomyces kasugaensis m338-m1 and sequenced. nine open reading frames (orfs), designated as orf a, b, c, d, e, f, g, h and i, were recognized in this region, although orf a was incomplete. orf g runs in the opposite direction to the others. the amino acid sequence deduced from orf h showed 98% similarity to that of the kasugamycin acetyltransferase from s. kasugaens ... | 1998 | 9589071 |
| flow cytometric assessment of the postantibiotic effect of methicillin on staphylococcus aureus. | the postantibiotic effect (pae) following a 2-h exposure of staphylococcus aureus nctc 6571 to methicillin (5x the mic) was investigated with fluorescent probes, 5-cyano-2,3-di-4-tolyl tetrazolium chloride (ctc), an indicator of respiratory activity, and the membrane potential-sensitive compound bis-(1,3-dibutylbarbituric acid) trimethine oxonol [dibac4(3)]. counts of the numbers of cfu on solid agar correlated well with information gained from the ctc and dibac4(3) fluorescence intensity distri ... | 1998 | 9593149 |
| molecular characterization of the phenylacetic acid catabolic pathway in pseudomonas putida u: the phenylacetyl-coa catabolon. | fourteen different genes included in a dna fragment of 18 kb are involved in the aerobic degradation of phenylacetic acid by pseudomonas putida u. this catabolic pathway appears to be organized in three contiguous operons that contain the following functional units: (i) a transport system, (ii) a phenylacetic acid activating enzyme, (iii) a ring-hydroxylation complex, (iv) a ring-opening protein, (v) a beta-oxidation-like system, and (vi) two regulatory genes. this pathway constitutes the common ... | 1998 | 9600981 |
| two nearly identical aromatic compound hydrolase genes in a strong polychlorinated biphenyl degrader, rhodococcus sp. strain rha1. | the two 2-hydroxy-6-oxohepta-2,4-dienoate (hohd) hydrolase genes, etbd1 and etbd2, were cloned from a strong polychlorinated biphenyl (pcb) degrader, rhodococcus sp. strain rha1, and their nucleotide sequences were determined. the etbd2 gene was located in the vicinity of bpha gene homologs and encoded an enzyme whose amino-terminal sequence was very similar to the amino-terminal sequence of the hohd hydrolase which was purified from rha1. using the etbd2 gene fragment as a probe, we cloned the ... | 1998 | 9603807 |
| towards a biocatalyst for (s)-styrene oxide production: characterization of the styrene degradation pathway of pseudomonas sp. strain vlb120. | in order to design a biocatalyst for the production of optically pure styrene oxide, an important building block in organic synthesis, the metabolic pathway and molecular biology of styrene degradation in pseudomonas sp. strain vlb120 was investigated. a 5.7-kb xhoi fragment, which contained on the same strand of dna six genes involved in styrene degradation, was isolated from a gene library of this organism in escherichia coli by screening for indigo formation. t7 rna polymerase expression expe ... | 1998 | 9603811 |
| construction of an efficient biologically contained pseudomonas putida strain and its survival in outdoor assays | active biological containment systems consist of two components, a killing element designed to induce cell death and a control element which modulates the expression of the killing function. we constructed a mini-tn5 transposon bearing a fusion of the plac promoter to the gef killing gene and a fusion of the pm promoter to the laci gene plus the positive regulator of the pm promoter, the xyls gene. this mini-tn5 transposon was transferred to the chromosome of pseudomonas putida cmc4, and in cult ... | 1998 | 9603816 |
| low-frequency horizontal transfer of an element containing the chlorocatechol degradation genes from pseudomonas sp. strain b13 to pseudomonas putida f1 and to indigenous bacteria in laboratory-scale activated-sludge microcosms. | the possibilities for low-frequency horizontal transfer of the self-transmissible chlorocatechol degradative genes (clc) from pseudomonas sp. strain b13 were investigated in activated-sludge microcosms. when the clc genes were transferred into an appropriate recipient bacterium such as pseudomonas putida f1, a new metabolic pathway for chlorobenzene degradation was formed by complementation which could be selected for by the addition of mono- or 1, 4-dichlorobenzene (cb). under optimized conditi ... | 1998 | 9603824 |
| cometabolism of 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene by pseudomonas acidovorans m3gy grown on biphenyl. | 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (dde), a toxic breakdown product of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (ddt), has traditionally been viewed as a dead-end metabolite: there are no published reports detailing enzymatic ring fission of dde by bacteria in either soil or pure culture. in this study, we investigated the ability of pseudomonas acidovorans m3gy to transform dde and its unchlorinated analog, 1,1-diphenylethylene (dpe). while strain m3gy could grow on dpe, cells gr ... | 1998 | 9603826 |
| new unstable variants of green fluorescent protein for studies of transient gene expression in bacteria. | use of the green fluorescent protein (gfp) from the jellyfish aequorea victoria is a powerful method for nondestructive in situ monitoring, since expression of green fluorescence does not require any substrate addition. to expand the use of gfp as a reporter protein, new variants have been constructed by the addition of short peptide sequences to the c-terminal end of intact gfp. this rendered the gfp susceptible to the action of indigenous housekeeping proteases, resulting in protein variants w ... | 1998 | 9603842 |
| establishment of new genetic traits in a microbial biofilm community. | conjugational transfer of the tol plasmid (pwwo) was analyzed in a flow chamber biofilm community engaged in benzyl alcohol degradation. the community consisted of three species, pseudomonas putida ri, acinetobacter sp. strain c6, and an unidentified isolate, d8. only p. putida ri could act as a recipient for the tol plasmid. cells carrying a chromosomally integrated laciq gene and a lacp-gfp-tagged version of the tol plasmid were introduced as donor strains in the biofilm community after its fo ... | 1998 | 9603843 |
| expression of the transposase gene tnpa of tn4652 is positively affected by integration host factor. | tn4652 is a derivative of the toluene degradation transposon tn4651 that belongs to the tn3 family of transposons (m. tsuda and t. iino, mol. gen. genet. 210:270-276, 1987). we have sequenced the transposase gene tnpa of transposon tn4652 and mapped its promoter to the right end of the element. the deduced amino acid sequence of tnpa revealed 96.2% identity with the putative transposase of tn5041. homology with other tn3 family transposases was only moderate (about 20 to 24% identity), suggestin ... | 1998 | 9603867 |
| distal cleavage of 3-chlorocatechol by an extradiol dioxygenase to 3-chloro-2-hydroxymuconic semialdehyde. | a 2,3-dihydroxybiphenyl 1,2-dioxygenase from the naphthalenesulfonate-degrading bacterium sphingomonas sp. strain bn6 oxidized 3-chlorocatechol to a yellow product with a strongly ph-dependent absorption maximum at 378 nm. a titration curve suggested (de)protonation of an ionizable group with a pka of 4.4. the product was isolated, purified, and converted, by treatment with diazomethane, to a dimethyl derivative and, by incubation with ammonium chloride, to a picolinic acid derivative. mass spec ... | 1998 | 9603871 |
| activation and repression of transcription at the double tandem divergent promoters for the xylr and xyls genes of the tol plasmid of pseudomonas putida. | the xylr and xyls genes are divergent and control transcription of the tol plasmid catabolic pathways for toluene metabolism. four promoters are found in the 300-bp intergenic region: pr1 and pr2 are constitutive sigma70-dependent tandem promoters that drive expression of xylr, while expression of the xyls gene is driven from ps2, a constitutive sigma70-dependent promoter, and by the regulatable sigma54 class ps1 promoter. in ps1 the xylr targets (upstream activator sequences [uass]) overlap the ... | 1998 | 9603877 |
| characterization of the hca cluster encoding the dioxygenolytic pathway for initial catabolism of 3-phenylpropionic acid in escherichia coli k-12. | we have identified, cloned, and sequenced the hca cluster encoding the dioxygenolytic pathway for initial catabolism of 3-phenylpropionic acid (pp) in escherichia coli k-12. this cluster maps at min 57.5 of the chromosome and is composed of five catabolic genes arranged as a putative operon (hcaa1a2cbd) and two additional genes transcribed in the opposite direction that encode a potential permease (hcat) and a regulator (hcar). sequence comparisons revealed that while hcaa1a2cd genes encode the ... | 1998 | 9603882 |
| implications of the xylq gene of tol plasmid pww102 for the evolution of aromatic catabolic pathways. | pseudomonas putida strain o2c2 is able to grow on toluene, m-xylene and p-xylene through benzoate and the corresponding methylbenzoates (toluates). the catabolic genes are encoded on a large tol plasmid, pww102, of > 220 kb. the complete catabolic genes were cloned on four large overlapping restriction fragments covering a total of 28 kb of the plasmid, which was carefully mapped by restriction enzyme analysis. the presence of the xyl genes on the cloned dna was confirmed by assay of representat ... | 1998 | 9611813 |
| purification, characterization, and gene analysis of catechol 2,3-dioxygenase from the aniline-assimilating bacterium pseudomonas species aw-2. | catechol 2,3-dioxygenase (c23d; ec 1.13.1.2) was purified to homogeneity from a cell extract of pseudomonas sp. aw-2 grown on aniline, and the purified c23d was characterized. the molecular mass estimated by gel filtration was 110 kda. the enzyme dissociated into four identical subunits each with the molecular mass of 33 kda. the enzyme had high activity for 3-methylcatechol as well as catechol, and differed from the enzyme from pseudomonas putida mt-2, which carries the tol plasmid, in optimal ... | 1998 | 9614705 |
| activity-dependent fluorescent labeling of bacteria that degrade toluene via toluene 2,3-dioxygenase. | alternative substrates for the toluene 2,3-dioxygenase pathway of several pseudomonads served as enzyme-activity-dependent fluorescent probes for the bacteria. phenylacetylene and cinnamonitrile were transformed to fluorescent and brightly colored products by pseudomonas putida f1, pseudomonas fluorescens cfs215, and burkholderia (pseudomonas) strain js150. active bacteria transformed phenylacetylene, producing bright yellow solutions containing the putative product 2-hydroxy-6-oxo-7-octyn-2,4-d ... | 1998 | 9615486 |
| characterization of the hcnabc gene cluster encoding hydrogen cyanide synthase and anaerobic regulation by anr in the strictly aerobic biocontrol agent pseudomonas fluorescens cha0. | the secondary metabolite hydrogen cyanide (hcn) is produced by pseudomonas fluorescens from glycine, essentially under microaerophilic conditions. the genetic basis of hcn synthesis in p. fluorescens cha0 was investigated. the contiguous structural genes hcnabc encoding hcn synthase were expressed from the t7 promoter in escherichia coli, resulting in hcn production in this bacterium. analysis of the nucleotide sequence of the hcnabc genes showed that each hcn synthase subunit was similar to kno ... | 1998 | 9620970 |
| cloning and comparison of flic genes and identification of glycosylation in the flagellin of pseudomonas aeruginosa a-type strains. | pseudomonas aeruginosa a-type strains produce flagellin proteins which vary in molecular weight between strains. to compare the properties of a-type flagellins, the flagellin genes of several pseudomonas aeruginosa a-type strains, as determined by interaction with specific anti-a monoclonal antibody, were cloned and sequenced. pcr amplification of the a-type flagellin gene fragments from five strains each yielded a 1.02-kb product, indicating that the gene size is not likely to be responsible fo ... | 1998 | 9620973 |
| crystal structure and enzyme mechanism of delta 5-3-ketosteroid isomerase from pseudomonas testosteroni. | bacterial delta 5-3-ketosteroid isomerase (ksi) from pseudomonas testosteroni has been intensively studied as a prototype for understanding an enzyme-catalyzed allylic rearrangement involving intramolecular proton transfer. asp38 serves as a general base to abstract the proton from the steroid c4-h, which is a much stronger base than the carboxyl group of this residue. this unfavorable proton transfer requires 11 kcal/mol of energy which has to be provided by favorable interactions between catal ... | 1998 | 9622484 |
| inhibition of human peripheral blood mononuclear cell proliferation by streptococcus pyogenes cell extract is associated with arginine deiminase activity. | streptococcus pyogenes (group a streptococcus) cell extracts (ce) have a remarkably powerful and dose-dependent inhibitory effect on antigen, superantigen, or mitogen-stimulated human peripheral blood mononuclear cell (pbmc) proliferation in vitro. purification of the inhibitory component present in s. pyogenes type m5 (manfredo strain) ce by anion-exchange chromatography followed by gel filtration chromatography showed that the inhibitor had an approximate native molecular mass of 100 kda. sodi ... | 1998 | 9632565 |
| heterogeneity in levels of vacuolating cytotoxin gene (vaca) transcription among helicobacter pylori strains. | broth culture supernatants from tox+ helicobacter pylori strains induce vacuolation of hela cells in vitro and contain vaca in concentrations that are higher than those found in supernatants from tox- h. pylori strains. to investigate the basis for this phenomenon, we analyzed the transcription of the vacuolating cytotoxin gene (vaca) in eight tox+ strains (each with a type s1/m1 vaca genotype) and nine tox- strains (each with a type s2/m2 vaca genotype). most of the tox+ and tox- strains tested ... | 1998 | 9632570 |
| segregational and structural instability of recombinant plasmid carrying genes for naphthalene degrading pathway. | the stability of recombinant plasmid carrying genes for naphthalene mineralization was determined. a strain of pseudomonas putida capable of mineralizing naphthalene (nap+) via salicylate (sal+) was isolated, and all regulatory and structural genes for the whole pathway were found to be encoded on a 25 kb ecori fragment of an approximately 83 kb plasmid present in this strain. the 25 kb ecori fragment was cloned into a tetracycline-resistant (tcr) cloning vector plafr3 and the recombinant plasmi ... | 1998 | 9633091 |
| biological production of semisynthetic opiates using genetically engineered bacteria. | semisynthetic derivatives of morphine and related alkaloids are in widespread clinical use. due to the complexity of these molecules, however, chemical transformations are difficult to achieve in high yields. we recently identified the powerful analgesic hydromorphone as an intermediate in the metabolism of morphine by pseudomonas putida m10. here we describe the construction of recombinant strains of escherichia coli that express morphine dehydrogenase and morphinone reductase. these strains ar ... | 1995 | 9634804 |
| anticancer efficacy in vivo and in vitro, synergy with 5-fluorouracil, and safety of recombinant methioninase. | the elevated exogenous-methionine dependency of tumors for growth has been observed in all major cancer cell types. we have previously cloned a methioninase (rmetase) from pseudomonas putida to deplete methionine. growth inhibition followed by apoptotic cell death was induced by treatment of tumor cells with rmetase in vitro. a single i.p. injection of 300 units of rmetase can lower the serum methionine level in the mice from 70 microm to less than 1 microm within 2 h and maintain this depleted ... | 1998 | 9635582 |
| efflux pumps involved in toluene tolerance in pseudomonas putida dot-t1e. | the basic mechanisms underlying solvent tolerance in pseudomonas putida dot-t1e are efflux pumps that remove the solvent from bacterial cell membranes. the solvent-tolerant p. putida dot-t1e grows in the presence of high concentrations (e.g., 1% [vol/vol]) of toluene and octanol. growth of p. putida dot-t1e cells in lb in the presence of toluene supplied via the gas phase has a clear effect on cell survival: the sudden addition of 0.3% (vol/vol) toluene to p. putida dot-t1e pregrown with toluene ... | 1998 | 9642183 |
| enantioselective uptake and degradation of the chiral herbicide dichlorprop [(rs)-2-(2,4-dichlorophenoxy)propanoic acid] by sphingomonas herbicidovorans mh. | sphingomonas herbicidovorans mh was able to completely degrade both enantiomers of the chiral herbicide dichlorprop [(rs)-2-(2,4-dichlorophenoxy)propanoic acid], with preferential degradation of the (s) enantiomer over the (r) enantiomer. these results are in agreement with the recently reported enantioselective degradation of mecoprop [(rs)-2-(4-chloro-2-methylphenoxy)propanoic acid] by this bacterium (c. zipper, k. nickel, w. angst, and h.-p. e. kohler, appl. environ. microbiol. 62:4318-4322, ... | 1998 | 9642189 |
| identification of a specific chaperone for sptp, a substrate of the centisome 63 type iii secretion system of salmonella typhimurium. | salmonella typhimurium uses of a type iii protein secretion system encoded at centisome 63 of its chromosome to deliver effector molecule into the host cell. these proteins stimulate host cell responses such as reorganization of the actin cytoskeleton and activation of transcription factors. one of these effector proteins is sptp, a tyrosine phosphatase that causes disruption of the host cell actin cytoskeleton. a characteristic feature of many substrates of type iii secretion systems is their a ... | 1998 | 9642193 |
| cloning, sequencing, and phenotypic characterization of the rpos gene from pseudomonas putida kt2440. | a gene homologous to the rpos gene of escherichia coli was cloned from a pseudomonas putida kt2440 gene bank by complementation of the rpos-deficient strain e. coli zk918. the rpos gene of p. putida complemented the acid sensitivity and catalase deficiency of the rpos mutant of e. coli and stimulated expression of the rpos-controlled promoter, bolap1. the gene was sequenced and found to be highly similar to the rpos genes of other gram-negative bacteria. like in other gram-negative bacteria, a h ... | 1998 | 9642197 |
| rapid method for the detection of genetically engineered microorganisms by polymerase chain reaction from soil and sediments. | a rapid and sensitive method for the detection of genetically engineered microorganisms in soil and sediments has been devised by in vitro amplification of the target dnas by a polymerase chain reaction. a cloned catechol 2,3-dioxygenase gene located on the recombinant plasmid poh101 was transferred to pseudomonas putida mmb2442 by triparental crossing and used as a target organism. for the polymerase chain reaction from soil and sediment samples, the template dna was released from a 100-mg soil ... | 1998 | 9643968 |
| root colonization by agrobacterium tumefaciens is reduced in cel, attb, attd, and attr mutants. | root colonization by agrobacterium tumefaciens was measured by using tomato and arabidopsis thaliana roots dipped in a bacterial suspension and planted in soil. wild-type bacteria showed extensive growth on tomato roots; the number of bacteria increased from 10(3) bacteria/cm of root length at the time of inoculation to more than 10(7) bacteria/cm after 10 days. the numbers of cellulose-minus and nonattaching attb, attd, and attr mutant bacteria were less than 1/10,000th the number of wild-type ... | 1998 | 9647796 |
| construction and use of an ipb dna module to generate pseudomonas strains with constitutive trichloroethene and isopropylbenzene oxidation activity. | pseudomonas sp. strain jr1 exhibits trichloroethene (tce) oxidation activity with isopropylbenzene (ipb) as the inducer substrate. we previously reported the genes encoding the first three enzymes of the ipb-degradative pathway (ipba1, ipba2, ipba3, ipba4, ipbb, and ipbc) and identified the initial ipb dioxygenase (ipba1 a2a3a4) as responsible for tce cooxidation (u. pflugmacher, b. averhoff, and g. gottschalk, appl. environ. microbiol. 62:3967-3977, 1996). primer extension analyses revealed mul ... | 1998 | 9647815 |
| small-scale dna sample preparation method for field pcr detection of microbial cells and spores in soil. | efficient, nonselective methods to obtain dna from the environment are needed for rapid and thorough analysis of introduced microorganisms in environmental samples and for analysis of microbial community diversity in soil. a small-scale procedure to rapidly extract and purify dna from soils was developed for in-the-field use. amounts of dna released from bacterial vegetative cells, bacterial endospores, and fungal conidia were compared by using hot-detergent treatment, freeze-thaw cycles, and be ... | 1998 | 9647816 |
| molecular cloning, nucleotide sequence, and expression in escherichia coli of a hemolytic toxin (aerolysin) gene from aeromonas trota. | aeromonas trota ak2, which was derived from atcc 49659 and produces the extracellular pore-forming hemolytic toxin aerolysin, was mutagenized with the transposon mini-tn5km1 to generate a hemolysin-deficient mutant, designated strain ak253. southern blotting data indicated that an 8.7-kb noti fragment of the genomic dna of strain ak253 contained the kanamycin resistance gene of mini-tn5km1. the 8.7-kb noti dna fragment was cloned into the vector pgem5zf(-) by selecting for kanamycin resistance, ... | 1998 | 9647817 |
| a two-component monooxygenase catalyzes both the hydroxylation of p-nitrophenol and the oxidative release of nitrite from 4-nitrocatechol in bacillus sphaericus js905. | bacteria that metabolize p-nitrophenol (pnp) oxidize the substrate to 3-ketoadipic acid via either hydroquinone or 1,2,4-trihydroxybenzene (thb); however, initial steps in the pathway for pnp biodegradation via thb are unclear. the product of initial hydroxylation of pnp could be either 4-nitrocatechol or 4-nitroresorcinol. here we describe the complete pathway for aerobic pnp degradation by bacillus sphaericus js905 that was isolated by selective enrichment from an agricultural soil in india. w ... | 1998 | 9647818 |
| cloning of a sphingomonas paucimobilis syk-6 gene encoding a novel oxygenase that cleaves lignin-related biphenyl and characterization of the enzyme. | sphingomonas paucimobilis syk-6 transforms 2,2'-dihydroxy-3,3'-dimethoxy-5,5'-dicarboxybiphenyl (ddva), a lignin-related biphenyl compound, to 5-carboxyvanillic acid via 2,2',3-trihydroxy-3'-methoxy-5,5'-dicarboxybiphenyl (oh-ddva) as an intermediate (15). the ring fission of oh-ddva is an essential step in the ddva degradative pathway. a 15-kb ecori fragment isolated from the cosmid library complemented the growth deficiency of a mutant on oh-ddva. subcloning and deletion analysis showed that a ... | 1998 | 9647824 |
| a highly selective pcr protocol for detecting 16s rrna genes of the genus pseudomonas (sensu stricto) in environmental samples. | pseudomonas species are plant, animal, and human pathogens; exhibit plant pathogen-suppressing properties useful in biological control; or express metabolic versatilities valued in biotechnology and bioremediation. specific detection of pseudomonas species in the environment may help us gain a more complete understanding of the ecological significance of these microorganisms. the objective of this study was to develop a pcr protocol for selective detection of pseudomonas (sensu stricto) in envir ... | 1998 | 9647828 |
| spatial and temporal variation of phenanthrene-degrading bacteria in intertidal sediments. | phenanthrene-degrading bacteria were isolated from a 1-m2 intertidal sediment site in boston harbor. samples were taken six times over 2 years. a total of 432 bacteria were isolated and characterized by biochemical testing. when clustered on the basis of phenotypic characteristics, the isolates could be separated into 68 groups at a similarity level of approximately 70%. several groups (a total of 200 isolates) corresponded to well-characterized species belonging the genera vibrio and pseudomona ... | 1998 | 9647830 |
| aerobic mineralization of 2,6-dichlorophenol by ralstonia sp. strain rk1. | a new aerobic bacterium was isolated from the sediment of a freshwater pond close to a contaminated site at amponville (france). it was enriched in a fixed-bed reactor fed with 2,6-dichlorophenol (2,6-dcp)as the sole carbon and energy source at ph 7.5 and room temperature. the degradation of 2,6-dcp followed monod kinetics at low initial concentrations. at concentrations above 300 microm (50 mg.liter-1), 2,6-dcp increasingly inhibited its own degradation. the base sequence of the 16s ribosomal d ... | 1998 | 9647831 |
| effect of insertion site and metabolic load on the environmental fitness of a genetically modified pseudomonas fluorescens isolate. | an isolate of pseudomonas fluorescens (sbw25) was modified with different marker genes (laczy, aph-1, and xyle). these marker genes were inserted singly or in combination into two separate (1 mbp apart) and presumably nonessential sites (-6- and ee) on the chromosome of sbw25. this allowed the production of a range of genetically modified sbw25 variants that differed with respect to insertion site of the marker genes and metabolic burden. the environmental fitness of the different sbw25 variants ... | 1998 | 9647841 |
| intergeneric transfer of conjugative and mobilizable plasmids harbored by escherichia coli in the gut of the soil microarthropod folsomia candida (collembola). | the gut of the soil microarthropod folsomia candida provides a habitat for a high density of bacterial cells (t. thimm, a. hoffmann, h. borkott, j. c. munch, and c. c. tebbe, appl. environ. microbiol. 64:2660-2669, 1998). we investigated whether these gut bacteria act as recipients for plasmids from escherichia coli. filter mating with e. coli donor cells and collected feces of f. candida revealed that the broad-host-range conjugative plasmid prp4-luc (prp4 with a luciferase marker gene) transfe ... | 1998 | 9647844 |
| the gut of the soil microarthropod folsomia candida (collembola) is a frequently changeable but selective habitat and a vector for microorganisms. | interaction potentials between soil microarthropods and microorganisms were investigated with folsomia candida (insecta, collembola) in microcosm laboratory experiments. microscopic analysis revealed that the volumes of the simple, rod-shaped guts of adult specimens varied with their feeding activity, from 0.7 to 11.2 nl. a dense layer of bacterial cells, associated with the peritrophic membrane, was detected in the midgut by scanning electron microscopy. depending on the molting stage, which oc ... | 1998 | 9647845 |
| in situ detection of high levels of horizontal plasmid transfer in marine bacterial communities. | gene transfer of the conjugative plasmid pbf1 from pseudomonas putida to indigenous bacteria in seawater was investigated with a detection system for gene transfer based on the green fluorescent protein (gfp) (c. dahlberg et al., mol. biol. evol. 15:385-390, 1998). pbf1 was tagged with the gfp gene controlled by a lac promoter which is down regulated in the donor cell by a chromosomal repressor (laciq). the plasmid donor cells (pseudomonas putida kt2442) subsequently do not express gfp. transfer ... | 1998 | 9647846 |
| a chromosomally based tod-luxcdabe whole-cell reporter for benzene, toluene, ethybenzene, and xylene (btex) sensing. | a tod-luxcdabe fusion was constructed and introduced into the chromosome of pseudomonas putida f1, yielding the strain tva8. this strain was used to examine the induction of the tod operon when exposed to benzene, toluene, ethylbenzene, and xylene (btex) compounds and aqueous solutions of jp-4 jet fuel constituents. since this system contained the complete lux cassette (luxcdabe), bacterial bioluminescence in response to putative chemical inducers of the tod operon was measured on-line in whole ... | 1998 | 9647859 |
| evaluation of the vitek 2 system for rapid identification of medically relevant gram-negative rods. | the new vitek 2 system (biomérieux) was evaluated at two independent sites with the identification card for gram-negative bacilli (id-gnb card). of the 845 strains tested, which represented 70 different taxa belonging to either the family enterobacteriaceae or the nonenteric bacilli, 716 (84.7%) were correctly identified at the species level. thirty-two (3.8%) additional strains were identified to the species level after the performance of simple, rapid manual tests (oxidase, hemolysis, indole r ... | 1998 | 9650942 |
| characterization of the maleylacetate reductase maca of rhodococcus opacus 1cp and evidence for the presence of an isofunctional enzyme. | maleylacetate reductases (ec 1.3.1.32) have been shown to contribute not only to the bacterial catabolism of some usual aromatic compounds like quinol or resorcinol but also to the degradation of aromatic compounds carrying unusual substituents, such as halogen atoms or nitro groups. genes coding for maleylacetate reductases so far have been analyzed mainly in chloroaromatic compound-utilizing proteobacteria, in which they were found to belong to specialized gene clusters for the turnover of chl ... | 1998 | 9657989 |
| the apee gene of salmonella typhimurium encodes an outer membrane esterase not present in escherichia coli. | salmonella typhimurium aper mutations lead to overproduction of an outer membrane-associated n-acetyl phenylalanine beta-naphthyl ester-cleaving esterase that is encoded by the apee gene (p. collin-osdoby and c. g. miller, mol. gen. genet. 243:674-680, 1994). this paper reports the cloning and nucleotide sequencing of the s. typhimurium apee gene as well as some properties of the esterase that it encodes. the predicted product of apee is a 69.9-kda protein which is processed to a 67-kda species ... | 1998 | 9657991 |
| evidence of two oxidative reaction steps initiating anaerobic degradation of resorcinol (1,3-dihydroxybenzene) by the denitrifying bacterium azoarcus anaerobius. | the denitrifying bacterium azoarcus anaerobius lufres1 grows anaerobically with resorcinol (1,3-dihydroxybenzene) as the sole source of carbon and energy. the anaerobic degradation of this compound was investigated in cell extracts. resorcinol reductase, the key enzyme for resorcinol catabolism in fermenting bacteria, was not present in this organism. instead, resorcinol was hydroxylated to hydroxyhydroquinone (hhq; 1,2,4-trihydroxybenzene) with nitrate or k3fe(cn)6 as the electron acceptor. hhq ... | 1998 | 9658009 |
| isolation and characterization of toluene-sensitive mutants from the toluene-resistant bacterium pseudomonas putida gm73. | to understand the mechanism underlying toluene resistance of a toluene-tolerant bacterium, pseudomonas putida gm73, we carried out tn5 mutagenesis and isolated eight toluene-sensitive mutants. none of the mutants grew in the presence of 20% (vol/vol) toluene in growth medium but exhibited differential sensitivity to toluene. when wild-type cells were treated with toluene (1% [vol/vol]) for 5 min, about 2% of the cells could form colonies. in the mutants ttg1, ttg2, ttg3, and ttg8, the same treat ... | 1998 | 9658016 |
| the central, surface-exposed region of the flagellar hook protein flge of campylobacter jejuni shows hypervariability among strains. | in a previous study, we observed that monoclonal antibodies raised against the hook protein flge of campylobacter jejuni lio 36, isolate 5226, bound exclusively to this strain. the aim of this study was to elucidate the molecular basis for these binding specificities. the hook protein-encoding gene flge of c. jejuni was cloned in escherichia coli and sequenced. the flge genes of four additional c. jejuni strains were amplified by pcr and also sequenced. comparison of the deduced amino acid seque ... | 1998 | 9658019 |
| fulminant hepatitis complicated by small intestine infection and massive hemorrhage. | a 34-year-old man diagnosed with fulminant hepatitis, caused by hepatitis b virus, and acute renal failure was referred to our hospital. after admission to the intensive care unit, the liver and renal failure were ameliorated. melena requiring transfusion occurred during the course of his illness. endoscopic examination demonstrated pseudomembranes, erosions, ulcers, and hemorrhage in the duodenum, the upper jejunum, and the terminal ileum, suggesting widespread lesions throughout the small inte ... | 1998 | 9658323 |
| pneumonia caused by pseudomonas putida with a mucoid phenotype. | | 1998 | 9659539 |
| the crystal structure of benzoylformate decarboxylase at 1.6 a resolution: diversity of catalytic residues in thiamin diphosphate-dependent enzymes. | the crystal structure of the thiamin diphosphate (thdp)-dependent enzyme benzoylformate decarboxylase (bfd), the third enzyme in the mandelate pathway of pseudomonas putida, has been solved by multiple isomorphous replacement at 1.6 a resolution and refined to an r-factor of 15.0% (free r = 18.6%). the structure of bfd has been compared to that of other thdp-dependent enzymes, including pyruvate decarboxylase. the overall architecture of bfd resembles that of the other family members, and cofact ... | 1998 | 9665697 |
| active monomeric and dimeric forms of pseudomonas putida glyoxalase i: evidence for 3d domain swapping. | 3d domain swapping of proteins involves the interconversion of a monomer containing a single domain-domain interface and a 2-fold symmetrical dimer containing two equivalent intermolecular interfaces. human glyoxalase i has the structure of a domain-swapped dimer [cameron, a. d., olin, b., ridderström, m., mannervik, b., and jones, t. a. (1997) embo j. 16, 3386-3395] but pseudomonas putida glyoxalase i has been reported to be monomeric [rhee, h.-i., murata, k., and kimura, a. (1986) biochem. bio ... | 1998 | 9671502 |
| sensorial and microbial effects of gaseous ozone on fresh scad (trachurus trachurus). | the bactericidal activity of gaseous ozone was investigated using a commercial ozone generator. five species of fish bacteria, pseudomonas putida, shewanella putrefaciens, brochothrix thermosphacta, enterobacter sp. and lactobacillus plantarum, were inoculated on agar surfaces and exposed to different ozonation times in a gas chamber. results showed ozone in relatively low concentrations (< 0.27 x 10(-3) g l-1) was an effective bactericide of vegetative cells of the five fish bacteria. the age o ... | 1998 | 9674134 |
| bacterial poly(3-hydroxyalkanoates) bearing carbon-carbon triple bonds. | production of poly(3-hydroxyalkanoates), phas, by pseudomonas oleovorans (p. oleovorans) and pseudomonas putida (p. putida) grown with mixtures of nonanoic acid, na, and 10-undecynoic acid, 10-und( identical with), were investigated. both microorganisms produced phas containing carbon-carbon triple bonds in fractions from 0 to 100%, depending on the composition of the carbon substrate mixture. the amounts of unsaturated repeating units in phas produced by p. oleovorans were higher than those in ... | 1998 | 9680410 |
| biochemical properties and substrate specificities of a recombinantly produced azotobacter vinelandii alginate lyase. | alginate is a polysaccharide composed of beta-d-mannuronic acid (m) and alpha-l-guluronic acid (g). an azotobacter vinelandii alginate lyase gene, algl, was cloned, sequenced, and expressed in escherichia coli. the deduced molecular mass of the corresponding protein is 41.4 kda, but a signal peptide is cleaved off, leaving a mature protein of 39 kda. sixty-three percent of the amino acids in this mature protein are identical to those in algl from pseudomonas aeruginosa. algl was partially purifi ... | 1998 | 9683471 |
| physical and genetic map of the obligate intracellular bacterium coxiella burnetii. | pulsed-field gel electrophoresis and pcr techniques have been used to construct a noti macrorestriction map of the obligate intracellular bacterium coxiella burnetii nine mile. the size of the chromosome has been determined to be 2,103 kb comprising 29 noti restriction fragments. the average resolution is 72.5 kb, or about 3. 5% of the genome. experimental data support the presence of a linear chromosome. published genes were localized on the physical map by southern hybridization. one gene, rec ... | 1998 | 9683477 |
| genetic analysis of dioxin dioxygenase of sphingomonas sp. strain rw1: catabolic genes dispersed on the genome. | the dioxin dioxygenase of sphingomonas sp. strain rw1 activates dibenzo-p-dioxin and dibenzofuran for further metabolism by introducing two atoms of oxygen at a pair of vicinal carbon atoms, one of which is involved in one of the bridges between the two aromatic rings, i.e., an angular dioxygenation. the dxna1 and dxna2 cistrons encoding this dioxygenase have been cloned and shown to be located just upstream of a hydrolase gene which specifies an enzyme involved in the subsequent step of the dib ... | 1998 | 9683494 |
| rapid detection and evaluation of clinical characteristics of emerging multiple-drug-resistant gram-negative rods carrying the metallo-beta-lactamase gene blaimp. | gram-negative rods (gnr) carrying the transferable carbapenem resistance gene blaimp, including pseudomonas aeruginosa and serratia marcescens, have been isolated from more than 20 hospitals in japan. although the emergence of such multiple-drug-resistant bacteria is of utmost clinical concern, little information in regard to the distribution of blaimp-positive gnr in hospitals and the clinical characteristics of infected patients is available. to address this, a system for the rapid detection o ... | 1998 | 9687398 |
| a glutathione s-transferase with activity towards cis-1, 2-dichloroepoxyethane is involved in isoprene utilization by rhodococcus sp. strain ad45. | rhodococcus sp. strain ad45 was isolated from an enrichment culture on isoprene (2-methyl-1,3-butadiene). isoprene-grown cells of strain ad45 oxidized isoprene to 3,4-epoxy-3-methyl-1-butene, cis-1, 2-dichloroethene to cis-1,2-dichloroepoxyethane, and trans-1, 2-dichloroethene to trans-1,2-dichloroepoxyethane. isoprene-grown cells also degraded cis-1,2-dichloroepoxyethane and trans-1, 2-dichloroepoxyethane. all organic chlorine was liberated as chloride during degradation of cis-1,2-dichloroepox ... | 1998 | 9687433 |