Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
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| cloning and molecular characterization of the genes for carbon monoxide dehydrogenase and localization of molybdopterin, flavin adenine dinucleotide, and iron-sulfur centers in the enzyme of hydrogenophaga pseudoflava. | carbon monoxide dehydrogenases (co-dh) are the enzymes responsible for the oxidation of co to carbon dioxide in carboxydobacteria and consist of three nonidentical subunits containing molybdopterin flavin adenine dinucleotide (fad), and two different iron-sulfur clusters (o. meyer, k. frunzke, d. gadkari, s. jacobitz, i. hugendieck, and m. kraut, fems microbiol. rev. 87:253-260, 1990). the three structural genes of co-dh in hydrogenophaga pseudoflava were cloned and characterized. the genes were ... | 1999 | 10482497 |
| involvement of the cis/trans isomerase cti in solvent resistance of pseudomonas putida dot-t1e. | pseudomonas putida dot-t1e is a solvent-resistant strain that is able to grow in the presence of high concentrations of toluene. we have cloned and sequenced the cti gene of this strain, which encodes the cis/trans isomerase, termed cti, that catalyzes the cis-trans isomerization of esterified fatty acids in phospholipids, mainly cis-oleic acid (c(16:1,9)) and cis-vaccenic acid (c(18:1,11)), in response to solvents. to determine the importance of this cis/trans isomerase for solvent resistance a ... | 1999 | 10482510 |
| role of the alkyl hydroperoxide reductase (ahpcf) gene in oxidative stress defense of the obligate anaerobe bacteroides fragilis. | in this study we report the identification and role of the alkyl hydroperoxide reductase (ahp) gene in bacteroides fragilis. the two components of ahp, ahpc, and ahpf, are organized in an operon, and the deduced amino acid sequences revealed that b. fragilis ahpcf shares approximately 60% identity to orthologues in other gram-positive and gram-negative bacteria. northern blot hybridization analysis of total rna showed that the ahpcf genes were transcribed as a polycistronic 2.4-kb mrna and that ... | 1999 | 10482511 |
| bacterial 2,4-dioxygenases: new members of the alpha/beta hydrolase-fold superfamily of enzymes functionally related to serine hydrolases. | 1h-3-hydroxy-4-oxoquinoline 2,4-dioxygenase (qdo) from pseudomonas putida 33/1 and 1h-3-hydroxy-4-oxoquinaldine 2,4-dioxygenase (hod) from arthrobacter ilicis rü61a catalyze an n-heterocyclic-ring cleavage reaction, generating n-formylanthranilate and n-acetylanthranilate, respectively, and carbon monoxide. amino acid sequence comparisons between qdo, hod, and a number of proteins belonging to the alpha/beta hydrolase-fold superfamily of enzymes and analysis of the similarity between the predict ... | 1999 | 10482514 |
| pathways of assimilative sulfur metabolism in pseudomonas putida. | cysteine and methionine biosynthesis was studied in pseudomonas putida s-313 and pseudomonas aeruginosa pao1. both these organisms used direct sulfhydrylation of o-succinylhomoserine for the synthesis of methionine but also contained substantial levels of o-acetylserine sulfhydrylase (cysteine synthase) activity. the enzymes of the transsulfuration pathway (cystathionine gamma-synthase and cystathionine beta-lyase) were expressed at low levels in both pseudomonads but were strongly upregulated d ... | 1999 | 10482527 |
| identification of a functional fur gene in bradyrhizobium japonicum. | the recent identification of the iron response regulator (irr) in bradyrhizobium japonicum raised the question of whether the global regulator fur is present in that organism. a fur gene homolog was isolated by the functional complementation of an escherichia coli fur mutant. the b. japonicum fur bound to a fur box dna element in vitro, and a fur mutant grown in iron-replete medium was derepressed for iron uptake activity. thus, b. japonicum expresses at least two regulators of iron metabolism. | 1999 | 10482529 |
| catechol 2,3-dioxygenase from the thermophilic, phenol-degrading bacillus thermoleovorans strain a2 has unexpected low thermal stability. | catechol 2,3-dioxygenase from the thermophilic bacillus thermoleovorans a2 was purified and characterized. the catechol 2,3-dioxygenase has a molecular mass of 135000da and consists of four identical subunits of 34 700 da. one iron per enzyme subunit was detected using atom absorption spectroscopy. enzyme activity was not inhibited by edta, suggesting that the iron is tightly bound. addition of hydrogen peroxide to the enzyme completely destroyed activity, indicating that the iron was in the div ... | 1999 | 10484174 |
| streptomyces aspartate transcarbamoylase is a dodecamer with dihydroorotase activity. | aspartate transcarbamoylase (atcase) was purified from streptomyces griseus. the enzyme is a dodecamer with a molecular mass of approximately 450 kda. the holoenzyme is a complex of atcase and active dihydroorotase (dhoase) subunits. the atcase and dhoase activities co-purify after gel filtration and ion-exchange chromatography. denaturing gel electrophoresis separates the holoenzyme into a 38-kda atcase polypeptide and a 47-kda dhoase polypeptide. the holoenzyme retained atcase and dhoase activ ... | 1999 | 10486051 |
| closed-loop control of bacterial high-cell-density fed-batch cultures: production of mcl-phas by pseudomonas putida kt2442 under single-substrate and cofeeding conditions. | pseudomonas putida kt2442 is able to accumulate medium-chain-length poly(3-hydroxyalkanoates) (mcl-phas) as intracellular inclusions on a variety of fatty acids and many other carbon sources. some of these substrates, such as octanoic acid, alkenoic acids, and halogenated derivatives, are toxic when present in excess. efficient production of mcl-phas on such toxic substrates therefore requires control of the carbon source concentration in the supernatant. in this study, we develop a closed-loop ... | 1999 | 10486129 |
| capillary electrophoresis-single-strand conformation polymorphism analysis for rapid identification of pseudomonas aeruginosa and other gram-negative nonfermenting bacilli recovered from patients with cystic fibrosis. | we used capillary electrophoresis-single-strand conformation polymorphism (ce-sscp) analysis of pcr-amplified 16s rrna gene fragments for rapid identification of pseudomonas aeruginosa and other gram-negative nonfermenting bacilli isolated from patients with cystic fibrosis (cf). target sequences were amplified by using forward and reverse primers labeled with various fluorescent dyes. the labeled pcr products were denatured by heating and separated by capillary gel electrophoresis with an autom ... | 1999 | 10488211 |
| cloning and sequencing of rpoh and identification of ftse-ftsx in pseudomonas putida ppg1. | the rpoh gene encoding the heat-shock sigma factor of pseudomonas putida was cloned by using its ability to complement the temperature-sensitive growth of the escherichia coli rpoh mutant. the cloned dna contained an open reading frame for a 284 amino acid sequence exhibiting high homology to the sigmah proteins of p. aeruginosa and e. coli. moreover, homologs to the cell division genes ftsx and ftse were found immediately upstream of the rpoh gene. | 1999 | 10492171 |
| a highly active, soluble mutant of the membrane-associated (s)-mandelate dehydrogenase from pseudomonas putida. | (s)-mandelate dehydrogenase (mdh) from pseudomonas putida, a member of the flavin mononucleotide-dependent alpha-hydroxy acid oxidase/dehydrogenase family, is a membrane-associated protein, in contrast to the more well-characterized members of this protein family including glycolate oxidase (gox) from spinach. in a previous study [mitra, b., et al. (1993) biochemistry 32, 12959-12967], the membrane association of mdh was correlated to a 53 amino acid segment in the interior of the primary sequen ... | 1999 | 10493804 |
| [resistance of certain strains of pseudomonas bacteria to toxic effect of heavy metal ions]. | the effect of heavy metal cations (cobalt, nickel, and copper) and the anion detergent sodium dodecyl sulfate (sds) on the barrier properties of the plasma membrane (pm) of the co-sensitive stain pseudomonas putida bs394 and the co-resistant strains pseudomonas sp. bs501 (wild-type strain) and pseudomonas putida bs394 (pbs501) (transformed strain) was studied by high-frequency electro-orientational spectroscopy. the cations were found to rank, in order of decreasing damage inflicted on the pm, a ... | 1999 | 10495974 |
| essential role of the iron-regulated outer membrane receptor faua in alcaligin siderophore-mediated iron uptake in bordetella species. | phenotypic analysis using heterologous host systems localized putative bordetella pertussis ferric alcaligin transport genes and fur-binding sequences to a 3.8-kb genetic region downstream from the alcr regulator gene. nucleotide sequencing identified a tonb-dependent receptor family homolog gene, faua, predicted to encode a polypeptide with high amino acid sequence similarity with known bacterial ferric siderophore receptors. in escherichia coli, the faua genes of both b. pertussis and bordetel ... | 1999 | 10498707 |
| cloning and characterization of a cryptic haloacid dehalogenase from burkholderia cepacia mba4. | burkholderia cepacia mba4 has been shown to produce a single dehalogenase batch culture. moreover, other cryptic dehalogenases were also detected when the cells were grown in continuous culture. in this paper, we report the cloning and characterization of one of the cryptic dehalogenases in mba4. this cryptic haloacid dehalogenase, designated chd1, was expressed constitutively in escherichia coli. this recombinant chd1 had a relative molecular weight of 58,000 and existed predominantly as a dime ... | 1999 | 10498712 |
| mutational analysis of the recj exonuclease of escherichia coli: identification of phosphoesterase motifs. | the recj gene, identified in escherichia coli, encodes a mg(+2)-dependent 5'-to-3' exonuclease with high specificity for single-strand dna. genetic and biochemical experiments implicate recj exonuclease in homologous recombination, base excision, and methyl-directed mismatch repair. genes encoding proteins with strong similarities to recj have been found in every eubacterial genome sequenced to date, with the exception of mycoplasma and mycobacterium tuberculosis. multiple genes encoding protein ... | 1999 | 10498723 |
| characterization of the phthalate permease ophd from burkholderia cepacia atcc 17616. | the ophd gene, encoding a permease for phthalate transport, was cloned from burkholderia cepacia atcc 17616. expression of the gene in escherichia coli results in the ability to transport phthalate rapidly into the cell. uptake inhibition experiments show that 4-hydroxyphthalate, 4-chlorophthalate, 4-methylphthalate, and cinchomeronate compete for the phthalate permease. an ophd knockout mutant of 17616 grows slightly more slowly on phthalate but is still able to take up phthalate at rates equiv ... | 1999 | 10498738 |
| purification and characterization of a novel naphthalene dioxygenase from rhodococcus sp. strain ncimb12038. | we report here the characterization of the catalytic component (isp(nar)) of a new naphthalene dioxygenase from rhodococcus sp. strain ncimb12038. the genes encoding the two subunits of isp(nar) are not homologous to their previously characterized counterparts in pseudomonas. the deduced amino acid sequences have only 33 and 29% identity with the corresponding subunits in pseudomonas putida ncib 9816-4, for which the tertiary structure has been reported. | 1999 | 10498739 |
| novel biodegradable aromatic plastics from a bacterial source. genetic and biochemical studies on a route of the phenylacetyl-coa catabolon. | novel biodegradable bacterial plastics, made up of units of 3-hydroxy-n-phenylalkanoic acids, are accumulated intracellularly by pseudomonas putida u due to the existence in this bacterium of (i) an acyl-coa synthetase (encoded by the fadd gene) that activates the aryl-precursors; (ii) a beta-oxidation pathway that affords 3-oh-aryl-coas, and (iii) a polymerization-depolymerization system (encoded in the pha locus) integrated by two polymerases (phac1 and phac2) and a depolymerase (phaz). the co ... | 1999 | 10506180 |
| characterization of mutations in the rpob gene in naturally rifampin-resistant rickettsia species. | rickettsiae are gram-negative, obligately intracellular bacteria responsible for arthropod-borne spotted fevers and typhus. experimental studies have delineated a cluster of naturally rifampin-resistant spotted fever group species. we sequenced the 4, 122- to 4,125-bp rna polymerase beta-subunit-encoding gene (rpob) from typhus and spotted fever group representatives and obtained partial sequences for all naturally rifampin-resistant species. a single point mutation resulting in a phenylalanine- ... | 1999 | 10508014 |
| halomethane:bisulfide/halide ion methyltransferase, an unusual corrinoid enzyme of environmental significance isolated from an aerobic methylotroph using chloromethane as the sole carbon source. | a novel dehalogenating/transhalogenating enzyme, halomethane:bisulfide/halide ion methyltransferase, has been isolated from the facultatively methylotrophic bacterium strain cc495, which uses chloromethane (ch(3)cl) as the sole carbon source. purification of the enzyme to homogeneity was achieved in high yield by anion-exchange chromatography and gel filtration. the methyltransferase was composed of a 67-kda protein with a corrinoid-bound cobalt atom. the purified enzyme was inactive but was act ... | 1999 | 10508052 |
| nitrogen availability to pseudomonas fluorescens df57 is limited during decomposition of barley straw in bulk soil and in the barley rhizosphere. | the availability of nitrogen to pseudomonas fluorescens df57 during straw degradation in bulk soil and in barley rhizosphere was studied by introducing a bioluminescent reporter strain (df57-n3), responding to nitrogen limitation, to model systems of varying complexity. df57-n3 was apparently not nitrogen limited in the natural and sterilized bulk soil used for these experiments. the soil was subsequently amended with barley straw, representing a plant residue with a high carbon-to-nitrogen rati ... | 1999 | 10508054 |
| purification and characterization of monovalent cation-activated levodione reductase from corynebacterium aquaticum m-13. | (6r)-2,2,6-trimethyl-1,4-cyclohexanedione (levodione) reductase was isolated from a cell extract of the soil isolate corynebacterium aquaticum m-13. this enzyme catalyzed regio- and stereoselective reduction of levodione to (4r,6r)-4-hydroxy-2,2, 6-trimethylcyclohexanone (actinol). the relative molecular mass of the enzyme was estimated to be 142,000 da by high-performance gel permeation chromatography and 36,000 da by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. the enzyme require ... | 1999 | 10508066 |
| identification and characterization of come and comf, two novel pilin-like competence factors involved in natural transformation of acinetobacter sp. strain bd413. | although the high level of competence for natural transformation of acinetobacter sp. strain bd413 has been the subject of numerous studies, only two competence genes, comc and comp, have been identified to date. by chromosomal walking analysis we found two overlapping open reading frames, designated come and comf, starting 61 bp downstream of comc. come and comf are expressed as stable proteins in escherichia coli, thus proving that they are indeed coding regions, but expression was successful ... | 1999 | 10508090 |
| utilization of trihalogenated propanes by agrobacterium radiobacter ad1 through heterologous expression of the haloalkane dehalogenase from rhodococcus sp. strain m15-3. | trihalogenated propanes are toxic and recalcitrant organic compounds. attempts to obtain pure bacterial cultures able to use these compounds as sole carbon and energy sources were unsuccessful. both the haloalkane dehalogenase from xanthobacter autotrophicus gj10 (dhla) and that from rhodococcus sp. strain m15-3 (dhaa) were found to dehalogenate trihalopropanes to 2,3-dihalogenated propanols, but the kinetic properties of the latter enzyme are much better. broad-host-range dehalogenase expressio ... | 1999 | 10508091 |
| diversity in butane monooxygenases among butane-grown bacteria. | butane monooxygenases of butane-grown pseudomonas butanovora, mycobacterium vaccae job5, and an environmental isolate, cf8, were compared at the physiological level. the presence of butane monooxygenases in these bacteria was indicated by the following results. (i) o(2) was required for butane degradation. (ii) 1-butanol was produced during butane degradation. (iii) acetylene inhibited both butane oxidation and 1-butanol production. the responses to the known monooxygenase inactivator, ethylene, ... | 1999 | 10508093 |
| mechanisms of action of carvacrol on the food-borne pathogen bacillus cereus. | carvacrol, a naturally occurring compound mainly present in the essential oil fraction of oregano and thyme, was studied for its effect on bioenergetic parameters of vegetative cells of the food-borne pathogen bacillus cereus. incubation for 30 min in the presence of 1 to 3 mm carvacrol reduced the viable cell numbers exponentially. carvacrol (2 mm) significantly depleted the intracellular atp pool to values close to 0 within 7 min. no proportional increase of the extracellular atp pool was obse ... | 1999 | 10508096 |
| green fluorescent protein-marked pseudomonas fluorescens: localization, viability, and activity in the natural barley rhizosphere. | the gfp-tagged pseudomonas fluorescens biocontrol strain dr54-bn14 was introduced into the barley rhizosphere. confocal laser scanning microscopy revealed that the rhizoplane populations of dr54-bn14 on 3- to 14-day-old roots were able to form microcolonies closely associated with the indigenous bacteria and that a majority of dr54-bn14 cells appeared small and almost coccoid. information on the viability of the inoculant was provided by a microcolony assay, while measurements of cell volume, th ... | 1999 | 10508101 |
| aerobic degradation of 1,1,1-trichloroethane by mycobacterium spp. isolated from soil. | two strains of 1,1,1-trichloroethane (tca)-degrading bacteria, ta5 and ta27, were isolated from soil and identified as mycobacterium spp. strains ta5 and ta27 could degrade 25 and 75 mg. liter of tca(-1) cometabolically in the presence of ethane as a carbon source, respectively. the compound 2,2,2-trichloroethanol was produced as a metabolite of the degradation process. | 1999 | 10508110 |
| a high-throughput digital imaging screen for the discovery and directed evolution of oxygenases. | oxygenases catalyze the hydroxylation of a wide variety of organic substrates. an ability to alter oxygenase substrate specificities and improve their activities and stabilities using recombinant dna techniques would expand their use in processes such as chemical synthesis and bioremediation. discovery and directed evolution of oxygenases require efficient screens that are sensitive to the activities of interest and can be applied to large numbers of crude enzyme samples. | 1999 | 10508682 |
| molecular cloning and cell-cycle-dependent expression of the acetyl-coa synthetase gene in tetrahymena cells. | to identify transcriptionally regulated mediators associated with the cell cycle, we adopted the differential mrna display technique for cell cultures of tetrahymena pyriformis synchronized by cyclic heat treatment. one cdna fragment that was expressed differently during synchronous cell division had a greatly decreased expression at 30 min after the end of heat treatment (eht). using this fragment as a probe, we isolated the full-length cdna for t. pyriformis acetyl-coa synthetase (tpacs) which ... | 1999 | 10510317 |
| stress survival of a genetically engineered pseudomonas in soil slurries: cytochrome p-450cam-catalyzed dehalogenation of chlorinated hydrocarbons. | biological treatment of hazardous chemical wastes has potential as an effective, practical, and economically viable process in above the ground treatment systems that consist of both genetically engineered microorganisms (gems) and bioreactors with process control instruments to create ideal conditions for biodegradation. a strain of pseudomonas putida coexpressing cytochrome p-450cam and luciferase (lux) that provides both the reductive detoxification potential of the hemoprotein and a mechanis ... | 1999 | 10514269 |
| cyclic-imide-hydrolyzing activity of d-hydantoinase from blastobacter sp. strain a17p-4. | the cyclic-imide-hydrolyzing activity of a prokaryotic cyclic-ureide-hydrolyzing enzyme, d-hydantoinase, was investigated. the enzyme hydrolyzed cyclic imides with bulky substituents such as 2-methylsuccinimide, 2-phenylsuccinimide, phthalimide, and 3,4-pyridine dicarboximide to the corresponding half-amides. however, simple cyclic imides without substituents, which are substrates of imidase (ie.g., succinimide, glutarimide, and sulfur-containing cyclic imides such as 2,4-thiazolidinedione and r ... | 1999 | 10515797 |
| opening the iron box: transcriptional metalloregulation by the fur protein. | 1999 | 10515908 | |
| cloning and sequence analysis of two pseudomonas flavoprotein xenobiotic reductases. | the genes encoding flavin mononucleotide-containing oxidoreductases, designated xenobiotic reductases, from pseudomonas putida ii-b and p. fluorescens i-c that removed nitrite from nitroglycerin (ng) by cleavage of the nitroester bond were cloned, sequenced, and characterized. the p. putida gene, xena, encodes a 39,702-da monomeric, nad(p)h-dependent flavoprotein that removes either the terminal or central nitro groups from ng and that reduces 2-cyclohexen-1-one but did not readily reduce 2,4,6- ... | 1999 | 10515912 |
| characterization of mext, the regulator of the mexe-mexf-oprn multidrug efflux system of pseudomonas aeruginosa. | we investigated the regulation of the mexef-oprn multidrug efflux system of pseudomonas aeruginosa, which is overexpressed in nfxc-type mutants and confers resistance to quinolones, chloramphenicol and trimethoprim. sequencing of the dna region upstream of the mexef-oprn operon revealed the presence of an open reading frame (orf) of 304 amino acids encoding a lysr-type transcriptional activator, termed mext. by using t7-polymerase, a 34-kda protein was expressed in escherichia coli from a plasmi ... | 1999 | 10515918 |
| in vitro characterization of peptidoglycan-associated lipoprotein (pal)-peptidoglycan and pal-tolb interactions. | the tol-peptidoglycan-associated lipoprotein (pal) system of escherichia coli is a multiprotein complex of the envelope involved in maintaining outer membrane integrity. pal and the periplasmic protein tolb, two components of this complex, are interacting with each other, and they have also been reported to interact with ompa and the major lipoprotein, two proteins interacting with the peptidoglycan. all these interactions suggest a role of the tol-pal system in anchoring the outer membrane to t ... | 1999 | 10515919 |
| regulation of the transposase of tn4652 by the transposon-encoded protein tnpc. | transposition is a dna reorganization reaction potentially deleterious for the host. the frequency of transposition is limited by the amount of transposase. therefore, strict regulation of a transposase is required to keep control over the destructive multiplication of the mobile element. we have shown previously that the expression of the transposase (tnpa) of the pseudomonas putida paw85 transposon tn4652 is positively affected by integration host factor. here, we present evidence that the amo ... | 1999 | 10515920 |
| substitution, insertion, deletion, suppression, and altered substrate specificity in functional protocatechuate 3,4-dioxygenases. | protocatechuate 3,4-dioxygenase is a member of a family of bacterial enzymes that cleave the aromatic rings of their substrates between two adjacent hydroxyl groups, a key reaction in microbial metabolism of varied environmental chemicals. in an appropriate genetic background, it is possible to select for acinetobacter strains containing spontaneous mutations blocking expression of pcah or -g, genes encoding the alpha and beta subunits of protocatechuate 3, 4-dioxygenase. the crystal structure o ... | 1999 | 10515940 |
| mutations of glutamate-84 at the putative potassium-binding site affect camphor binding and oxidation by cytochrome p450cam. | cytochrome p450cam (cyp101) from pseudomonas putida is unusual among p450 enzymes in that it exhibits co-operative binding between the substrate camphor and a potassium ion. this behaviour has been investigated by mutagenesis of glu84, a surface residue which forms part of the cation-binding site. substitutions that neutralize or reverse the charge of this side chain are shown to disrupt the co-operativity of potassium and camphor binding by p450cam, and also to influence the catalytic activity. ... | 1999 | 10518786 |
| rapid identification of burkholderia pseudomallei in blood cultures by a monoclonal antibody assay. | burkholderia pseudomallei is the causative agent of melioidosis. in northeast thailand, this gram-negative bacterium is a major cause of mortality from septicemia. the definitive diagnosis of this disease is made by bacterial culture. in this study, we produced a monoclonal antibody (mab) specific to the 30-kda protein of b. pseudomallei by in vivo and in vitro immunization of balb/c mice with a crude culture filtrate antigen. the mab could directly agglutinate with all 243 clinical isolates of ... | 1999 | 10523570 |
| roles of active site aromatic residues in catalysis by ketosteroid isomerase from pseudomonas putida biotype b. | the aromatic residues phe-54, phe-82, and trp-116 in the hydrophobic substrate-binding pocket of delta(5)-3-ketosteroid isomerase from pseudomonas putida biotype b have been characterized in their roles in steroid binding and catalysis. kinetic and equilibrium binding analyses were carried out for the mutant enzymes with the substitutions phe-54 --> ala or leu, phe-82 --> ala or leu, and trp-116 --> ala, phe, or tyr. the removal of their bulky, aromatic side chains at any of these three position ... | 1999 | 10529226 |
| crystallization and preliminary diffraction studies of two quinoprotein alcohol dehydrogenases (adhs): a soluble monomeric adh from pseudomonas putida hk5 (adh-iib) and a heterotrimeric membrane-bound adh from gluconobacter suboxydans (adh-gs). | crystals of a soluble monomeric quinocytochrome alcohol dehydrogenase (adh-iib) and of a trimeric membrane-associated quinocytochrome alcohol dehydrogenase (adh-gs) have been obtained. the adh-iib crystals are triclinic, with one monomer in the unit cell, and were obtained in the presence of peg 8000, sodium citrate, hepes buffer and 2-propanol. x-ray data were collected at 110 k to 1. 9 a resolution (r(merge) = 6.4%) and the orientation of a methanol dehydrogenase search molecule (from methylop ... | 1999 | 10531500 |
| bioavailability of water-polluting sulfonoaromatic compounds. | highly substituted arenesulfonates are chemically stable compounds with a range of industrial applications, and they are widely regarded as being poorly degradable. we did enrichment cultures for bacteria able to utilise the sulfonate moiety of 14 compounds, and we obtained mixed cultures that were able to desulfonate each compound. the products formed were usually identified as the corresponding phenol, but because we could not obtain pure cultures, we followed up these findings with quantitati ... | 1999 | 10531657 |
| a protein residing at the subunit interface of the bacterial ribosome. | surface labeling of escherichia coli ribosomes with the use of the tritium bombardment technique has revealed a minor unidentified ribosome-bound protein (spot y) that is hidden in the 70s ribosome and becomes highly labeled on dissociation of the 70s ribosome into subunits. in the present work, the n-terminal sequence of the protein y was determined and its gene was identified as yfia, an orf located upstream the phe operon of e. coli. this 12.7-kda protein was isolated and characterized. an af ... | 1999 | 10535924 |
| calibrating bacterial evolution. | attempts to calibrate bacterial evolution have relied on the assumption that rates of molecular sequence divergence in bacteria are similar to those of higher eukaryotes, or to those of the few bacterial taxa for which ancestors can be reliably dated from ecological or geological evidence. despite similarities in the substitution rates estimated for some lineages, comparisons of the relative rates of evolution at different classes of nucleotide sites indicate no basis for their universal applica ... | 1999 | 10535975 |
| bacterial populations in an anthropogenically disturbed stream: comparison of different seasons. | abstract to determine the effects of environmental changes on stream bacterial populations, assemblage- and population-level measurements were compared between an anthropogenically disturbed stream and an undisturbed reference stream during different seasons. physical and chemical variables monitored at two disturbed sites from a stream affected by multiple environmental perturbations confirmed discernibly different water quality from three reference sites: two from an adjacent, undisturbed wate ... | 1999 | 10541785 |
| transcriptional activation of the chlorocatechol degradative genes of ralstonia eutropha nh9. | ralstonia eutropha (formerly alcaligenes eutrophus) nh9 degrades 3-chlorobenzoate via the modified ortho-cleavage pathway. a ca. 5.7-kb six-gene cluster is responsible for chlorocatechol degradation: the cbnabcd operon encoding the degradative enzymes (including orfx of unknown function) and the divergently transcribed cbnr gene encoding the lysr-type transcriptional regulator of the cbn operon. the cbnrab orfxcd gene cluster is nearly identical to the chlorocatechol genes (tcbrcd orfxef) of the ... | 1999 | 10542171 |
| cloning and sequencing of a novel meta-cleavage dioxygenase gene whose product is involved in degradation of gamma-hexachlorocyclohexane in sphingomonas paucimobilis. | sphingomonas (formerly pseudomonas) paucimobilis ut26 utilizes gamma-hexachlorocyclohexane (gamma-hch), a halogenated organic insecticide, as a sole source of carbon and energy. in a previous study, we showed that gamma-hch is degraded to chlorohydroquinone (chq) and then to hydroquinone (hq), although the rate of reaction from chq to hq was slow (k. miyauchi, s. k. suh, y. nagata, and m. takagi, j. bacteriol. 180:1354-1359, 1998). in this study, we cloned and characterized a gene, designated li ... | 1999 | 10542173 |
| characterization of cadmium uptake in lactobacillus plantarum and isolation of cadmium and manganese uptake mutants. | two different cd(2+) uptake systems were identified in lactobacillus plantarum. one is a high-affinity, high-velocity mn(2+) uptake system which also takes up cd(2+) and is induced by mn(2+) starvation. the calculated k(m) and v(max) are 0.26 microm and 3.6 micromol g of dry cell(-1) min(-1), respectively. unlike mn(2+) uptake, which is facilitated by citrate and related tricarboxylic acids, cd(2+) uptake is weakly inhibited by citrate. cd(2+) and mn(2+) are competitive inhibitors of each other, ... | 1999 | 10543780 |
| biochemical and genetic analyses of ferulic acid catabolism in pseudomonas sp. strain hr199. | the gene loci fcs, encoding feruloyl coenzyme a (feruloyl-coa) synthetase, ech, encoding enoyl-coa hydratase/aldolase, and aat, encoding beta-ketothiolase, which are involved in the catabolism of ferulic acid and eugenol in pseudomonas sp. strain hr199 (dsm7063), were localized on a dna region covered by two ecori fragments (e230 and e94), which were recently cloned from a pseudomonas sp. strain hr199 genomic library in the cosmid pvk100. the nucleotide sequences of parts of fragments e230 and e ... | 1999 | 10543794 |
| flagellate predation on a bacterial model community: interplay of size-selective grazing, specific bacterial cell size, and bacterial community composition. | the influence of grazing by the bacterivorous nanoflagellate ochromonas sp. strain ds on the taxonomic and morphological structures of a complex bacterial community was studied in one-stage chemostat experiments. a bacterial community, consisting of at least 30 different strains, was fed with a complex carbon source under conditions of low growth rate (0.5 day(-1) when nongrazed) and low substrate concentration (9 mg liter(-1)). before and after the introduction of the predator, the bacterial co ... | 1999 | 10543797 |
| methanotroph diversity in landfill soil: isolation of novel type i and type ii methanotrophs whose presence was suggested by culture-independent 16s ribosomal dna analysis. | the diversity of the methanotrophic community in mildly acidic landfill cover soil was assessed by three methods: two culture-independent molecular approaches and a traditional culture-based approach. for the first of the molecular studies, two primer pairs specific for the 16s rrna gene of validly published type i (including the former type x) and type ii methanotrophs were identified and tested. these primers were used to amplify directly extracted soil dna, and the products were used to const ... | 1999 | 10543800 |
| identification of a transcriptional activator (chnr) and a 6-oxohexanoate dehydrogenase (chne) in the cyclohexanol catabolic pathway in acinetobacter sp. strain ncimb 9871 and localization of the genes that encode them. | we identified chnr, a gene encoding an arac-xyls type of transcriptional activator that regulates the expression of chnb, the structural gene for cyclohexanone monooxygenase (chmo) in acinetobacter sp. strain ncimb 9871. the gene sequence of chne, which encodes an nadp(+)-linked 6-oxohexanoate dehydrogenase, the enzyme catalyzing the fifth step of cyclohexanol degradation, was also determined. the gene arrangement is chnb-chne-chnr. the predicted molecular masses of the three polypeptides were v ... | 1999 | 10543838 |
| importance of illegitimate recombination and transposition in is30-associated excision events. | in the present study we report on the excision of is30 elements and is30-derived composite transposons. frequent loss of is30 was observed during dissolution of dimeric is30 structures, containing ir-ir junctions, leading to resealed donor molecules. in contrast, unambiguous transpositional excision resulting in resealed remainder products could not be identified in the case of a monomeric element. the bias in the excision of monomeric and dimeric is30 structures indicates a difference in the mo ... | 1999 | 10545262 |
| an electrochemical study of the factors responsible for modulating the reduction potential of putidaredoxin. | the gene coding for putidaredoxin has been synthesized using a combination of chemical and enzymatic methods and subsequently expressed in escherichia coli. the recombinant protein characterized by electronic spectroscopy, mass spectrometry, and electrochemistry was found to be identical to putidaredoxin obtained from pseudomonas putida. polylysine was found to promote the fast and reversible electrochemistry of putidaredoxin at negatively charged electrodes such as indium-doped tin oxide or gol ... | 1999 | 10550696 |
| effect of wild-type and mutant plant growth-promoting rhizobacteria on the rooting of mung bean cuttings. | mung bean cuttings were dipped in solutions of wild type and mutant forms of the plant growth-promoting rhizobacterium pseudomonas putida gr12-2 and then incubated for several days until roots formed. the bacteria p. putida gr12-2 and p. putida gr12-2/aux1 mutant do not produce detectable levels of the enzyme 1-aminocyclopropane-1-carboxylate (acc) deaminase, whereas p. putida gr12-2/acd36 is an acc deaminase minus mutant. all bacteria produce the phytohormone indole-3-acetic acid (iaa), and p. ... | 1999 | 10552131 |
| optical detection of cytochrome p450 by sensitizer-linked substrates. | the ability to detect, characterize, and manipulate specific biomolecules in complex media is critical for understanding metabolic processes. particularly important targets are oxygenases (cytochromes p450) involved in drug metabolism and many disease states, including liver and kidney dysfunction, neurological disorders, and cancer. we have found that ru photosensitizers linked to p450 substrates specifically recognize submicromolar cytochrome p450(cam) in the presence of other heme proteins. i ... | 1999 | 10557259 |
| a novel lipolytic enzyme located in the outer membrane of pseudomonas aeruginosa. | a lipase-negative deletion mutant of pseudomonas aeruginosa pao1 still showed extracellular lipolytic activity toward short-chain p-nitrophenylesters. by screening a genomic dna library of p. aeruginosa pao1, an esterase gene, esta, was identified, cloned, and sequenced, revealing an open reading frame of 1,941 bp. the product of esta is a 69.5-kda protein, which is probably processed by removal of an n-terminal signal peptide to yield a 67-kda mature protein. a molecular mass of 66 kda was dete ... | 1999 | 10559163 |
| recruitment of rna polymerase is a rate-limiting step for the activation of the sigma(54) promoter pu of pseudomonas putida. | the activity of the sigma(54)-promoter pu of pseudomonas putida was examined in vitro with a dna template lacking upstream activating sequences, such that rna polymerase can be activated by the enhancer-binding protein xylr only from solution. although the transcription activation pathway in this system lacked the step of integration host factor (ihf)-mediated looping of the xylr.dna complex toward the prebound rna polymerase, ihf still stimulated promoter activity. the positive effect of ihf be ... | 1999 | 10559273 |
| a siderophore from pseudomonas putida type a1: structural and biological characterization. | a siderophore from a root-colonizing, plant-beneficial fluorescent pseudomonas (p. putida type a1) isolated from chickpea rhizosphere was studied. culture conditions required for optimal production of the chromophore by the organism were standardized. the compound was purified by gel filtration, ion exchange and rp-hplc chromatographic procedures. the purified compound exhibited siderophore activity for p. putida and antifungal activity on phytopathogens, fusarium oxysporum f. sp. ciceri and hel ... | 1999 | 10561535 |
| transformations of codeine to important semisynthetic opiate derivatives by pseudomonas putida m10. | a biotransformation mixture which contained codeine and washed cells of pseudomonas putida m10 gave rise to a number of transformation products that are of clinical importance which included hydrocodone, dihydrocodeine and 14beta-hydroxycodeine. incubations with the same organism and codeinone gave rise to 14beta-hydroxycodeinone and 14beta-hydroxycodeine. cell-free extracts and membrane fractions of p. putida m10 were shown to catalyse the 14beta-hydroxylation of codeinone. in addition, the pot ... | 1999 | 10564799 |
| organization and sequences of p-hydroxybenzaldehyde dehydrogenase and other plasmid-encoded genes for early enzymes of the p-cresol degradative pathway in pseudomonas putida ncimb 9866 and 9869. | the gene (designated pcha) encoding the aldehyde dehydrogenase that is required to metabolise the p-hydroxybenzaldehyde produced by the degradation of p-cresol in pseudomonas putida ncimb 9866 and 9869 has been identified on plasmids pra4000 and pra500, respectively. the gene lies immediately upstream of the pchc and pchf genes encoding the subunits of p-cresol methylhydroxylase (pcmh), the preceeding enzyme in the p-cresol degradative pathway. in pra500 the latter genes are followed by the gene ... | 1999 | 10565539 |
| identification of a novel mycobacterial histone h1 homologue (hupb) as an antigenic target of panca monoclonal antibody and serum immunoglobulin a from patients with crohn's disease. | panca is a marker antibody associated with inflammatory bowel disease (ibd), including most patients with ulcerative colitis and a subset with crohn's disease. this study addressed the hypothesis that panca reacts with an antigen(s) of microbial agents potentially relevant to ibd pathogenesis. using a panca monoclonal antibody, we have previously identified the c-terminal basic random-coil domain of histone h1 as a panca autoantigen. blast analysis of the peptide databases revealed h1 epitope ho ... | 1999 | 10569769 |
| transcriptional regulation by iron of genes encoding iron- and manganese-superoxide dismutases from pseudomonas putida. | genes from pseudomonas putida (pp), soda, encoding manganese-superoxide dismutase (mnsod) and, sodb, iron-superoxide dismutase (fesod) were cloned by hybridization with digoxigenin (dig)-labeled pcr products generated from pp genomic dna. the sodb gene had a 594 bp open reading frame (orf), corresponding to 198 amino acids (aa), and a transcript of 880 bases. the soda gene contained a 609 bp orf encoding 203 aa and was transcribed as part of a polycistronic operon, consisting of orfy-fumc-orfx-s ... | 1999 | 10571042 |
| providencia stuartii genes activated by cell-to-cell signaling and identification of a gene required for production or activity of an extracellular factor. | by utilizing reporter transposons, five providencia stuartii genes that are activated by the accumulation of self-produced extracellular signals have been identified. these genes have been designated cma for conditioned medium activated. the presence of conditioned medium from stationary-phase cultures grown in rich media resulted in the premature activation of each gene in cells at early log phase, with activation values ranging from 6- to 26-fold. preparation of conditioned medium from an m9 s ... | 1999 | 10572119 |
| characterization of the bradyrhizobium japonicum ftsh gene and its product. | the bradyrhizobium japonicum ftsh gene was cloned by using a set of widely applicable degenerated oligonucleotides. western blot experiments indicated that the ftsh protein was produced under standard growth conditions and that it was not heat inducible. attempts to delete the ftsh gene in b. japonicum failed, suggesting a pivotal cellular function of this gene. the expression of b. japonicum ftsh in an ftsh-negative escherichia coli strain significantly enhanced the fitness of this mutant and r ... | 1999 | 10572147 |
| sequence heterogeneity of the ferripyoverdine uptake (fpva), but not the ferric uptake regulator (fur), genes among strains of the fluorescent pseudomonads pseudomonas aeruginosa, pseudomonas aureofaciens, pseudomonas fluorescens and pseudomonas putida. | pseudomonas aeruginosa, pseudomonas aureofaciens, pseudomonas fluorescens and pseudomonas putida are of importance to medicine, agriculture and biocycling. these microbes acquire ferric ion via the use of the siderophores pyochelin and the family known as the pyoverdines or pseudobactins. the ferric uptake regulator (fur) gene is responsible, at least in part, for the regulation of siderophore synthesis and uptake in p. aeruginosa. to determine whether the organisms contain single or multiple ho ... | 1999 | 10581691 |
| cis-chlorobenzene dihydrodiol dehydrogenase (tcbb) from pseudomonas sp. strain p51, expressed in escherichia coli dh5alpha(ptcb149), catalyzes enantioselective dehydrogenase reactions. | cis-chlorobenzene dihydrodiol dehydrogenase (cdd) from pseudomonas sp. strain p51, cloned into escherichia coli dh5alpha(ptcb149) was able to oxidize cis-dihydrodihydroxy derivatives (cis-dihydrodiols) of dihydronaphthalene, indene, and four para-substituted toluenes to the corresponding catechols. during the incubation of a nonracemic mixture of cis-1,2-indandiol, only the (+)-cis-(1r,2s) enantiomer was oxidized; the (-)-cis-(s,2r) enantiomer remained unchanged. cdd oxidized both enantiomers of ... | 1999 | 10583971 |
| removal of mercury from chloralkali electrolysis wastewater by a mercury-resistant pseudomonas putida strain. | a mercury-resistant bacterial strain which is able to reduce ionic mercury to metallic mercury was used to remediate in laboratory columns mercury-containing wastewater produced during electrolytic production of chlorine. factory effluents from several chloralkali plants in europe were analyzed, and these effluents contained total mercury concentrations between 1.6 and 7.6 mg/liter and high chloride concentrations (up to 25 g/liter) and had ph values which were either acidic (ph 2.4) or alkaline ... | 1999 | 10583977 |
| utilization of heterologous siderophores enhances levels of iron available to pseudomonas putida in the rhizosphere. | pseudomonas spp. have the capacity to utilize siderophores produced by diverse species of bacteria and fungi, and the present study was initiated to determine if siderophores produced by rhizosphere microorganisms enhance the levels of iron available to a strain of pseudomonas putida in this natural habitat. we used a previously described transcriptional fusion (pvd-inaz) between an iron-regulated promoter (pvd) and the ice nucleation reporter gene (inaz) to detect alterations in iron availabili ... | 1999 | 10583989 |
| linking toluene degradation with specific microbial populations in soil. | phospholipid fatty acid (plfa) analysis of a soil microbial community was coupled with (13)c isotope tracer analysis to measure the community's response to addition of 35 microg of [(13)c]toluene ml of soil solution(-1). after 119 h of incubation with toluene, 96% of the incorporated (13)c was detected in only 16 of the total 59 plfas (27%) extracted from the soil. of the total (13)c-enriched plfas, 85% were identical to the plfas contained in a toluene-metabolizing bacterium isolated from the s ... | 1999 | 10583996 |
| cloning, sequencing, and characterization of genomic subtracted sequences from listeria monocytogenes. | individual sequences of a genomic subtracted, pcr-amplified, mixed-sequence probe (gs probe) were cloned and sequenced. the gs probe differentiated restriction fragment length polymorphism patterns for listeria monocytogenes but did not hybridize with members of other bacterial genera. sequence analysis identified several l. monocytogenes sequences already present in the genbank database; the putative identities of other sequences were inferred from homology data, and still other sequences did n ... | 1999 | 10583999 |
| involvement of manganese in conversion of phenylalanine to benzaldehyde by lactic acid bacteria. | we examined the involvement of mn(ii) in the conversion of phenylalanine to benzaldehyde in cell extracts of lactic acid bacteria. experiments performed with lactobacillus plantarum demonstrated that mn(ii), present at high levels in this strain, is involved in benzaldehyde formation by catalyzing the conversion of phenylpyruvic acid. experiments performed with various lactic acid bacterial strains belonging to different genera revealed that benzaldehyde formation in a strain was related to a hi ... | 1999 | 10584022 |
| engineering of a stable whole-cell biocatalyst capable of (s)-styrene oxide formation for continuous two-liquid-phase applications. | recombinant strains of pseudomonas putida kt2440 carrying genetic expression cassettes with xylene oxygenase- and styrene monooxygenase-encoding genes on their chromosomes could be induced in shaking-flask experiments to specific activities that rivaled those of multicopy-plasmid-based escherichia coli recombinants. such strains maintained the introduced styrene oxidation activity in continuous two-liquid-phase cultures for at least 100 generations, although at a lower level than in the shaking- ... | 1999 | 10584030 |
| recombinational repair of dna damage in escherichia coli and bacteriophage lambda. | although homologous recombination and dna repair phenomena in bacteria were initially extensively studied without regard to any relationship between the two, it is now appreciated that dna repair and homologous recombination are related through dna replication. in escherichia coli, two-strand dna damage, generated mostly during replication on a template dna containing one-strand damage, is repaired by recombination with a homologous intact duplex, usually the sister chromosome. the two major typ ... | 1999 | 10585965 |
| conjugal transfer of a tol-like plasmid and extension of the catabolic potential of pseudomonas putida f1. | strain mx was isolated from a petrol-contaminated soil, after enrichment on minimal medium with 0.5% (v/v) meta-xylene as a sole carbon source. the strain was tentatively characterized as pseudomonas putida and harboured a large plasmid (pmx) containing xyl genes involved in toluene or meta-xylene degradation pathways via an alkyl monooxygenase and a catechol 2,3-dioxygenase. this new tol-like plasmid was stable over two hundred generations and was self-transferable. after conjugal transfer to p ... | 1999 | 10588042 |
| identification and molecular characterization of the eugenol hydroxylase genes (ehya/ehyb) of pseudomonas sp. strain hr199. | the gene loci ehya and ehyb, which are involved in the bioconversion of eugenol to coniferyl alcohol by pseudomonas sp. strain hr199 (dsm 7063), were identified as the structural genes of a eugenol hydroxylase that represents an enzyme of the flavocytochrome c class. these genes were localized downstream of the eugenol catabolism genes vana and vanb, encoding vanillate-o-demethylase, on an ecori fragment (e230) that has recently been cloned from a pseudomonas sp. strain hr199 genomic library. th ... | 1999 | 10591845 |
| srpdb (signal recognition particle database). | the signal recognition particle database (srpdb) is maintained at the university of texas health science center at tyler, texas, and organizes srp-related information about srp rna, srp proteins and the srp receptor. srpdb is accessible on the www at the url http://psyche.uthct.edu/dbs/srpdb/srpdb.++ +html. a mirror site of the srpdb is located in europe at the university of göteborg, sweden (http://www.medkem. gu.se/dbs/srpdb/srpdb.html ). this release of srpdb adds 10 new srp rna sequences (a ... | 2000 | 10592215 |
| increased flow of fatty acids toward beta-oxidation in developing seeds of arabidopsis deficient in diacylglycerol acyltransferase activity or synthesizing medium-chain-length fatty acids. | synthesis of polyhydroxyalkanoates (phas) from intermediates of fatty acid beta-oxidation was used as a tool to study fatty acid degradation in developing seeds of arabidopsis. transgenic plants expressing a peroxisomal pha synthase under the control of a napin promoter accumulated pha in developing seeds to a final level of 0. 06 mg g(-1) dry weight. in plants co-expressing a plastidial acyl-acyl carrier protein thioesterase from cuphea lanceolata and a peroxisomal pha synthase, approximately 1 ... | 1999 | 10594123 |
| expression of marker rnas in pseudomonas putida. | a broad-host-range vector that expresses a unique artificial rna in pseudomonas putida has been developed. this vector was derived from the plasmid pbbr1mcs and incorporates regulatory regions from the escherichia coli ribosomal operon, rrnb. these include the promoters p1 and p2, and the terminators t1 and t2. the gene for the artificial rna was derived from vibrio proteolyticus 5s rrna. the artificial rna product accumulates to a level that is 10-20% of the total 5s rrna in p. putida. the rna ... | 2000 | 10594220 |
| properties of p-cresol methylhydroxylase flavoprotein overproduced by escherichia coli. | the alpha(2)beta(2) flavocytochrome p-cresol methylhydroxylase (pcmh) from pseudomonas putida is composed of a flavoprotein homodimer (alpha(2) or pchf(2); m(r) = 119 kda) with a cytochrome monomer (beta, pchc; m(r) = 9.3 kda) bound to each pchf subunit. escherichia coli bl21(de3) has been transformed with a vector for expression of the pchf gene, and pchf is overproduced by this strain as the homodimer. during purification, it was recognized that some pchf had fad bound, while the remainder was ... | 1999 | 10600124 |
| acetone formation in the vibrio family: a new pathway for bacterial leucine catabolism. | there is current interest in biological sources of acetone, a volatile organic compound that impacts atmospheric chemistry. here, we determined that leucine-dependent acetone formation is widespread in the vibrionaceae. sixteen vibrio isolates, two listonella species, and two photobacterium angustum isolates produced acetone in the presence of l-leucine. shewanella isolates produced much less acetone. growth of vibrio splendidus and p. angustum in a fermentor with controlled aeration revealed th ... | 1999 | 10601206 |
| evaluation of mycobacterium tuberculosis genes involved in resistance to killing by human macrophages. | a coinfection assay was developed to examine mycobacterium tuberculosis genes suspected to be involved in resistance to killing by human macrophages. thp-1 macrophages were infected with a mixture of equal numbers of recombinant mycobacterium smegmatis lr222 bacteria expressing an m. tuberculosis gene and wild-type m. smegmatis lr222 bacteria expressing the xyle gene. at various times after infection, the infected macrophages were lysed and the bacteria were plated. the resulting colonies were s ... | 2000 | 10603413 |
| bacillus subtilis lrpc is a sequence-independent dna-binding and dna-bending protein which bridges dna. | genetic evidence suggests that the bacillus subtilis lrpc gene product participates in cell growth and sporulation. the purified lrpc protein, which has a predicted molecular mass of 16.4 kda, is a tetramer in solution. lrpc binds with higher affinity ( k (app) approximately 80 nm) to intrinsically curved dna than to non-curved dna ( k (app) approximately 700 nm). dnase i footprinting and the supercoiling of relaxed circular plasmid dna in the presence of topoisomerase i revealed that lrpc induc ... | 2000 | 10606655 |
| an aerotaxis transducer gene from pseudomonas putida. | an aerotaxis gene, aer, was cloned from pseudomonas putida prs2000. a p. putida aer mutant displayed an altered aerotactic response in a capillary assay. wild-type p. putida clustered at the air/liquid interface. in contrast, the aer mutant did not cluster at the interface, but instead formed a diffuse band at a distance from the meniscus. wild-type aer, provided in trans, complemented the aer mutant to an aerotactic response that was stronger than wild-type. the p. putida aer sequence is simila ... | 2000 | 10612751 |
| characterization of the endogenous plasmid from pseudomonas alcaligenes ncib 9867: dna sequence and mechanism of transfer. | the endogenous plasmid pra2 from pseudomonas alcaligenes ncib 9867 was determined to have 32,743 bp with a g+c content of 59.8%. sequence analysis predicted a total of 29 open reading frames, with approximately half of them contributing towards the functions of plasmid replication, mobilization, and stability. the pac25i restriction-modification system and two mobile elements, tn5563 and is1633, were physically localized. an additional eight open reading frames with unknown functions were also d ... | 2000 | 10613866 |
| proline catabolism by pseudomonas putida: cloning, characterization, and expression of the put genes in the presence of root exudates. | pseudomonas putida kt2442 is a root-colonizing strain which can use proline, one of the major components in root exudates, as its sole carbon and nitrogen source. a p. putida mutant unable to grow with proline as the sole carbon and nitrogen source was isolated after random mini-tn5-km mutagenesis. the mini-tn5 insertion was located at the puta gene, which is adjacent to and divergent from the putp gene. the puta gene codes for a protein of 1,315 amino acid residues which is homologous to the pu ... | 2000 | 10613867 |
| hbar, a 4-hydroxybenzoate sensor and fnr-crp superfamily member, regulates anaerobic 4-hydroxybenzoate degradation by rhodopseudomonas palustris. | under anaerobic conditions, structurally diverse aromatic compounds are catabolized by bacteria to form benzoyl-coenzyme a (benzoyl-coa), the starting compound for a central reductive pathway for aromatic ring degradation. the structural genes required for the conversion of 4-hydroxybenzoate (4-hba) to benzoyl-coa by rhodopseudomonas palustris have been identified. here we describe a regulatory gene, hbar, that is part of the 4-hba degradation gene cluster. an hbar mutant that was constructed wa ... | 2000 | 10613868 |
| identification of a new class of 5'-adenylylsulfate (aps) reductases from sulfate-assimilating bacteria. | a gene was cloned from burkholderia cepacia dbo1 that is homologous with escherichia coli cysh encoding 3'-phosphoadenylylsulfate (paps) reductase. the b. cepacia gene is the most recent addition to a growing list of cysh homologs from a diverse group of sulfate-assimilating bacteria whose products show greater homology to plant 5'-adenylylsulfate (aps) reductase than they do to e. coli cysh. the evidence reported here shows that the cysh from one of the species, pseudomonas aeruginosa, encodes ... | 2000 | 10613872 |
| convenient test for screening metallo-beta-lactamase-producing gram-negative bacteria by using thiol compounds. | a simple disk diffusion test was constructed for detection of imp-1-type metallo-beta-lactamase-producing gram-negative bacteria. two kirby-bauer disks containing ceftazidime (caz) and a filter disk containing a metallo-beta-lactamase inhibitor were used in this test. several imp-1 inhibitors such as thiol compounds including 2-mercaptopropionic acid, heavy metal salts, and edta were evaluated for this test. two caz disks were placed on a mueller-hinton agar plate on which a bacterial suspension ... | 2000 | 10618060 |
| differentiation of phylogenetically related slowly growing mycobacteria by their gyrb sequences. | the conventional methods for identifying mycobacterial species are based on their phenotypic characterization. since some problematic species are slow growers, their taxonomy takes several weeks or months to identify. the ribosomal dna (rdna) sequence-based identification strategy has been adopted to solve this problem. more recently, the gyrb sequences have been shown to be useful phylogenetic markers for the identification of species. we determined the gyrb sequences of 43 slowly growing strai ... | 2000 | 10618105 |
| importance of pfka for rapid growth of enterobacter cloacae during colonization of crop seeds. | enterobacter cloacae a-11 is a prototrophic, glycolytic mutant of strain 501r3 with a single transposon insertion in pfka. the populations of strain a-11 on cucumber and radish seeds were smaller than the populations of strain 501r3 in natural soil, but the populations of these two strains on pea, soybean, sunflower, and sweet corn seeds were similar (d. p. roberts, p. d. dery, i. yucel, j. buyer, m. a. holtman, and d. y. kobayashi, appl. environ. microbiol. 65:2513-2519, 1999). the net effect o ... | 2000 | 10618207 |
| the ntrb and ntrc genes are involved in the regulation of poly-3-hydroxybutyrate biosynthesis by ammonia in azospirillum brasilense sp7. | azospirillum brasilense sp7 and its ntra (rpon), ntrbc, and ntrc mutants have been evaluated for their capabilities of poly-3-hydroxybutyrate (phb) accumulation in media with high and low ammonia concentrations. it was observed that the ntrbc and ntrc mutants can produce phb in both low- and high-c/n-ratio media, while no significant phb production was observed for the wild type or the ntra mutant in low-c/n-ratio media. further investigation by fermentation analysis indicated that the ntrbc and ... | 2000 | 10618211 |
| generation of novel bacterial regulatory proteins that detect priority pollutant phenols. | the genetic systems of bacteria that have the ability to use organic pollutants as carbon and energy sources can be adapted to create bacterial biosensors for the detection of industrial pollution. the creation of bacterial biosensors is hampered by a lack of information about the genetic systems that control production of bacterial enzymes that metabolize pollutants. we have attempted to overcome this problem through modification of dmpr, a regulatory protein for the phenol degradation pathway ... | 2000 | 10618218 |
| production and comparison of peptide siderophores from strains of distantly related pathovars of pseudomonas syringae and pseudomonas viridiflava lmg 2352. | the production of peptide siderophores and the variation in siderophore production among strains of pseudomonas syringae and pseudomonas viridiflava were investigated. an antibiose test was used to select a free amino acid-containing agar medium favorable for production of fluorescent siderophores by two p. syringae strains. a culture technique in which both liquid and solid asparagine-containing culture media were used proved to be reproducible and highly effective for inducing production of si ... | 2000 | 10618243 |
| molecular characterization of the toxic cyanobacterium cylindrospermopsis raciborskii and design of a species-specific pcr. | cylindrospermopsis raciborskii is a toxic-bloom-forming cyanobacterium that is commonly found in tropical to subtropical climatic regions worldwide, but it is also recognized as a common component of cyanobacterial communities in temperate climates. genetic profiles of c. raciborskii were examined in 19 cultured isolates originating from geographically diverse regions of australia and represented by two distinct morphotypes. a 609-bp region of rpoc1, a dna-dependent rna polymerase gene, was ampl ... | 2000 | 10618244 |
| role of leaf surface sugars in colonization of plants by bacterial epiphytes. | the relationship between nutrients leached onto the leaf surface and the colonization of plants by bacteria was studied by measuring both the abundance of simple sugars and the growth of pseudomonas fluorescens on individual bean leaves. data obtained in this study indicate that the population size of epiphytic bacteria on plants under environmentally favorable conditions is limited by the abundance of carbon sources on the leaf surface. sugars were depleted during the course of bacterial coloni ... | 2000 | 10618250 |
| quantification of different eubacterium spp. in human fecal samples with species-specific 16s rrna-targeted oligonucleotide probes. | species-specific 16s rrna-targeted, cy3 (indocarbocyanine)-labeled oligonucleotide probes were designed and validated to quantify different eubacterium species in human fecal samples. probes were directed at eubacterium barkeri, e. biforme, e. contortum, e. cylindroides (two probes), e. dolichum, e. hadrum, e. lentum, e. limosum, e. moniliforme, and e. ventriosum. the specificity of the probes was tested with the type strains and a range of common intestinal bacteria. with one exception, none of ... | 2000 | 10618251 |
| dual labeling with green fluorescent proteins for confocal microscopy. | we report a dual labeling technique involving two green fluorescent protein (gfp) variants that is compatible with confocal microscopy. two lasers were used to obtain images of (i) mixed cultures of cells, where one species contained gfpuv and another species contained gfpmut2 or gfpmut3, and (ii) a single species containing both gfpuv and gfpmut2 in the same cell. this method shows promise for monitoring gene expression and as a nondestructive and in situ technique for confocal microscopy of mu ... | 2000 | 10618256 |