| the sequence and crystal structure of the alpha-amino acid ester hydrolase from xanthomonas citri define a new family of beta-lactam antibiotic acylases. | alpha-amino acid ester hydrolases (aehs) catalyze the hydrolysis and synthesis of esters and amides with an alpha-amino group. as such, they can synthesize beta-lactam antibiotics from acyl compounds and beta-lactam nuclei obtained from the hydrolysis of natural antibiotics. this article describes the gene sequence and the 1.9-a resolution crystal structure of the aeh from xanthomonas citri. the enzyme consists of an alpha/beta-hydrolase fold domain, a helical cap domain, and a jellyroll beta-do ... | 2003 | 12684501 |
| osteomyelitis of the pelvis caused by rhodococcus equi in a two-year-old horse. | a 2-year-old female quarter horse was evaluated for hind limb lameness, fever (40 degrees c [104 degrees f]), and lethargy of 2 weeks' duration. hypoproteinemia characterized by hypoalbuminemia and hyperfibrinogenemia was detected. abdominal ultrasonography revealed thickening of the right dorsal colon wall. treatment was instituted for putative right dorsal coliis. lameness evaluation localized signs of pain to the lumbar vertebrae or pelvis. radiography performed with the horse standing and nu ... | 2003 | 12685788 |
| biodegradation of plasticizers by rhodococcus rhodochrous. | rhodococcus rhodochrous was grown in the presence of one of three plasticizers: bis 2-ethylhexyl adipate (beha), dioctyl phthalate (dop) or dioctyl terephthalate (dotp). none of the plasticizers were degraded unless another carbon source, such as hexadecane, was also present. when r. rhodochrous was grown with hexadecane as a co-substrate, beha was completely degraded and the dop was degraded slightly. about half of the dotp was degraded, if hexadecane were present. in all of these growth studie ... | 2002 | 12688586 |
| heterologous expression of rhodococcus opacus l-amino acid oxidase in streptomyces lividans. | l-amino acid oxidase (l-aao) from rhodococcus opacus is a highly enantioselective enzyme with a broad substrate specificity that catalyses the oxidation of l-amino acids to keto acids. the lao-gene (ay053450) from r. opacus was cloned into different escherichia coli and streptomyces lividans expression vectors. expression in e. coli resulted in the accumulation of insoluble protein, but s. lividans was a suitable host for the heterologous production of l-aao. when using the thiostrepton-inducibl ... | 2003 | 12699695 |
| substrate specificity and expression of three 2,3-dihydroxybiphenyl 1,2-dioxygenases from rhodococcus globerulus strain p6. | rhodococcus globerulus strain p6 contains at least three genes, bphc1, bphc2, and bphc3, coding for 2,3-dihydroxybiphenyl 1,2-dioxygenases; the latter two specify enzymes of the family of one-domain extradiol dioxygenases. in order to assess the importance of these different isoenzymes for the broad catabolic activity of this organism towards the degradation of polychlorinated biphenyls (pcbs), the capacities of recombinant enzymes expressed in escherichia coli to transform different chlorosubst ... | 2003 | 12700274 |
| the cell wall of the pathogenic bacterium rhodococcus equi contains two channel-forming proteins with different properties. | we have identified in organic solvent extracts of whole cells of the gram-positive pathogen rhodococcus equi two channel-forming proteins with different and complementary properties. the isolated proteins were able to increase the specific conductance of artificial lipid bilayer membranes made from phosphatidylcholine-phosphatidylserine mixtures by the formation of channels able to be permeated by ions. the channel-forming protein pora(req) (r. equi pore a) is characterized by the formation of c ... | 2003 | 12700275 |
| in vitro susceptibilities of rhodococcus equi and other common equine pathogens to azithromycin, clarithromycin, and 20 other antimicrobials. | the objective of this study was to determine in vitro activities of azithromycin (azm), clarithromycin (clr), and 20 other antimicrobial agents against rhodococcus equi and other common equine bacterial pathogens. a total of 201 bacterial isolates from various equine clinical samples were examined. clr was more active than azm against r. equi, with mics at which 90% of the isolates were inhibited of 0.12 and 1.0 micro g/ml, respectively. other antimicrobial agents highly active against at least ... | 2003 | 12709351 |
| cloning, sequence analysis, and heterologous expression of the gene encoding a (s)-specific alcohol dehydrogenase from rhodococcus erythropolis dsm 43297. | the gene encoding an (s)-specific nad-dependent alcohol dehydrogenase (re-adh) was isolated from the genomic dna of rhodococcus erythropolis dsm 43297. the nucleotide sequence of 1,047 bp, coding for 348 amino acids, was cloned in escherichia coli cells and successfully expressed. the subunit molecular mass as deduced from the amino acid sequence was determined to be 36.026 kda. the recombinant enzyme exhibited high thermostability, which facilitated its purification by heat treatment, followed ... | 2003 | 12719937 |
| homologous npdgi genes in 2,4-dinitrophenol- and 4-nitrophenol-degrading rhodococcus spp. | rhodococcus (opacus) erythropolis hl pm-1 grows on 2,4,6-trinitrophenol or 2,4-dinitrophenol (2,4-dnp) as a sole nitrogen source. the nadph-dependent f(420) reductase (ndfr; encoded by npdg) and the hydride transferase ii (htii; encoded by npdi) of the strain were previously shown to convert both nitrophenols to their respective hydride meisenheimer complexes. in the present study, npdg and npdi were amplified from six 2,4-dnp degrading rhodococcus spp. the genes showed sequence similarities of ... | 2003 | 12732545 |
| purification and characterization of an inverting stereo- and enantioselective sec-alkylsulfatase from the gram-positive bacterium rhodococcus ruber dsm 44541. | whole cells of rhodococcus ruber dsm 44541 were found to hydrolyze (+/-)-2-octyl sulfate in a stereo- and enantiospecific fashion. when growing on a complex medium, the cells produced two sec-alkylsulfatases and (at least) one prim-alkylsulfatase in the absence of an inducer, such as a sec-alkyl sulfate or a sec-alcohol. from the crude cell-free lysate, two proteins responsible for sulfate ester hydrolysis (designated rs1 and rs2) were separated from each other based on their different hydrophob ... | 2003 | 12732552 |
| [rhodococcus equi pneumonia in aids: a case report] | we describe the first case, in campania, of rhodococcus equi pneumonia in an hiv positive subject. the clinical symptoms resolved after antibiotic therapy. the pulmonary lesion at 10 months of radiological follow up results just partially reduced in its diameters. | 1998 | 12732826 |
| immunoglobulin g subisotype responses of pneumonic and healthy, exposed foals and adult horses to rhodococcus equi virulence-associated proteins. | rhodococcus equi causes severe pyogranulomatous pneumonia in foals and in immunocompromised humans. replication of virulent isolates within macrophages correlates with the presence of a large plasmid which encodes a family of seven virulence-associated proteins (vapa and vapc to vaph), whose functions are unknown. although cell-mediated immunity is thought to be crucial in eliminating r. equi infection, antibody partially protects foals. the antibody response to both vapa and vapc was similar in ... | 2003 | 12738629 |
| culture collections and biochemistry. | this review describes the relationships and links between culture collections, which act as sources of genomes, transcriptomes, proteome, and metabolomes, and fields of research biochemistry that demand their support and help. in addition, the invaluable but not always rewarded efforts of these organizations as a source and conservator of organism diversity is discussed. biological waste-water treatment, ethanol as a non-finite source of energy, rhodococcus fascians as the source of a citrus-jui ... | 2003 | 12739105 |
| macrokinetic and quantitative microbial investigation on a bench-scale biofilter treating styrene-polluted gaseous streams. | we performed a macrokinetic and quantitative microbial investigation of a continuously operating bench-scale biofilter treating styrene-polluted gases. the device was filled with a mixture of peat and glass beads as packing medium and inoculated with the styrene-oxidizing strain, rhodococcus rhodochrous al ncimb 13259. the experimental data of styrene and microbial concentrations, obtained at different biofilter heights, were used to evaluate the pollutant concentration profiles as well as the i ... | 2003 | 12740930 |
| 2-(2'-hydroxyphenyl)benzene sulfinate desulfinase from the thermophilic desulfurizing bacterium paenibacillus sp. strain a11-2: purification and characterization. | 2-(2'-hydroxyphenyl)benzene sulfinate (hpbsi) desulfinase (tdsb), which catalyzes the final step of desulfurization of dibenzothiophene (dbt), was purified from a thermophilic dbt- and benzothiophene (bt)-desulfurizing bacterium: paenibacillus sp. strain a11-2. the molecular mass of the purified enzyme was 31 kda and 39 kda by gel filtration and sodium dodecyl sulfate polyacrylamide gel electrophoresis, respectively, suggesting a monomeric structure. the optimal temperature and ph for the reacti ... | 2003 | 12743754 |
| [fluorene cometabolism by rhodococcus rhodochrous and pseudomonas fluorescens]. | the transformation of fluorene by rhodococcus rhodochrous strain 172 grown on sucrose and pseudomonas fluorescens strain 26k grown on glycerol was studied as a function of the substrate concentration and the growth phase. under certain cultivation conditions, fluorene was completely consumed from the medium. the specific transformation rate of fluorene was considerably higher when it was transformed in the presence of the cosubstrates than when it served as the sole carbon source. an approach to ... | 2003 | 12751243 |
| [production of oil-processing compounds by microorganisms from the daqing oil field, china]. | twenty pure cultures isolated from formation waters of the daqing oil field were studied with respect to their capacity to produce surface-active compounds in media with individual hydrocarbons, lower alcohols, and fatty acids. aerobic saprotrophic bacteria belonging to the genera bacillus, brevibacillus, rhodococcus, dietzia, kocuria, gordonia, cellulomonas, clavibacter, pseudomonas, and acinetobacter decreased the surface tension of cultivation media from 55-63 to 28-44 mn/m. strains of bacill ... | 2003 | 12751245 |
| [the effect of sulfur on the hydrocarbon-oxidizing bacteria of different genera growth]. | | 2003 | 12751253 |
| biotransformation of beta-ketosulfides to produce chiral beta-hydroxysulfoxides. | the biotransformations of a series of substituted phenylthio-2-propanone and benzylthio-2-propanone were carried out using helminthosporium sp. nrrl 4671, mortierella isabellina atcc 42613, or rhodococcus erythropolis igts8. several products gave microbial oxidation of sulfide to sulfoxide and reduction of carbonyl to secondary alcohol, producing beta-hydroxysulfoxides in medium to high enantiomeric and diastereomeric purities. fungal biotransformations using helminthosporium sp. and m. isabelli ... | 2003 | 12759809 |
| nitrile biotransformations for highly efficient and enantioselective syntheses of electrophilic oxiranecarboxamides. | catalyzed by a nitrile hydratase/amidase-containing microbial rhodococcus sp. aj270 whole-cell catalyst, a number of racemic trans-2,3-epoxy-3-arylpropanenitriles 1 underwent rapid and efficient hydrolysis under very mild conditions to afford 2r,3s-2-arylglycidamides 2 in excellent yield with enantiomeric excess higher than 99.5%. the overall enantioselectivity of the biotransformations originated from the combined effects of a dominantly high 2s-enantioselective amidase and low 2s-enantioselect ... | 2003 | 12762774 |
| cloning and sequence analysis of the ces10 gene encoding a sphingomonas paucimobilis esterase. | the ces10 gene of the gellan gum-producing strain sphingomonas paucimobilis atcc 31461 was cloned and sequenced. multi-sequence alignment of the deduced protein indicated that ces10 belongs to the serine hydrolase family with a potential catalytic triad comprising ser(153) (within the g-x-s-x-g consensus sequence), his(75) and asp(125). the mixed block results obtained following pattern search and the low identities detected in a blast analysis indicate that ces10 is significantly different from ... | 2003 | 12764567 |
| host-vector system for phenol-degrading rhodococcus erythropolis based on corynebacterium plasmids. | the strain rhodococcus erythropolis ccm2595, which was shown to degrade phenol, was chosen for genetic studies. to facilitate strain improvement using the methods of gene manipulation, the technique of genetic transfer was introduced and cloning vectors were constructed. using the plasmid pfaj2574, an electrotransformation procedure yielding up to 7x10(4) transformants/microg dna was optimized. escherichia coli- r. erythropolis shuttle vectors were constructed using the replicons psr1 and pga1 f ... | 2003 | 12764568 |
| lipoarabinomannans: from structure to biosynthesis. | mycobacterium tuberculosis, the causative agent of tuberculosis, is one of the most effective human pathogens and the molecular basis of its virulence remains poorly understood. here, we review our current knowledge about the structure and biosynthesis of the mycobacterial cell-wall lipoglycans, lipoarabinomannans (lam). lam are ubiquitous of mycobacteria and appear as the most potent non-peptidic molecules to modulate the host immune response. nevertheless, lam structure differs according to th ... | 2003 | 12765785 |
| quantitative structure-activity relationships for the enantioselectivity of oxirane ring-opening catalyzed by epoxide hydrolases. | the enantioselective ring-opening catalyzed by epoxide hydrolases originating from seven different sources of a series of 2,2-disubstituted oxiranes containing alkyl chains of different lengths, unsaturated (alkenyl, alkinyl) and aromatic groups as well as electronegative heteroatoms at various positions within the side chain was analyzed by quantitative structure-activity relationships. models for the enantioselectivity were derived with the aid of multiple linear regression analysis (mlr) usin ... | 2003 | 12767152 |
| structure of rhodococcus erythropolis limonene-1,2-epoxide hydrolase reveals a novel active site. | epoxide hydrolases are essential for the processing of epoxide-containing compounds in detoxification or metabolism. the classic epoxide hydrolases have an alpha/beta hydrolase fold and act via a two-step reaction mechanism including an enzyme-substrate intermediate. we report here the structure of the limonene-1,2-epoxide hydrolase from rhodococcus erythropolis, solved using single-wavelength anomalous dispersion from a selenomethionine-substituted protein and refined at 1.2 a resolution. this ... | 2003 | 12773375 |
| structural and functional features of rhodococcus ruber lipoarabinomannan. | the genus rhodococcus is part of the phylogenetic group nocardioform actinomycetes, which also includes the genus mycobacterium: members of this phylogenetic group have a characteristic cell envelope structure, which is dominated by various complex lipids. among these, lipoglycans are of particular interest since mycobacterial lipoarabinomannans are important immunomodulatory molecules that are likely to be involved in the subsequent fate of mycobacterial bacilli once inside phagocytic cells. rh ... | 2003 | 12777484 |
| a genetic system for the rapid isolation of aromatic-ring-hydroxylating dioxygenase activities. | aromatic-ring-hydroxylating dioxygenases (arhdos) are key enzymes in the aerobic bacterial metabolism of aromatic compounds. they are of biotechnological importance as they function as biocatalysts in the stereospecific synthesis of chiral synthons and the degradation of aromatic pollutants. this report describes the development and validation of a system for the rapid isolation and characterization of specific arhdo activities. the system is based on the identification of arhdo gene segments th ... | 2003 | 12777487 |
| partial genome sequencing of rhodococcus equi atcc 33701. | preliminary analysis of a partial (30% coverage) genome sequence of rhodococcus equi has revealed a number of important features. the most notable was the extent of the homology of genes identified with those of mycobacterium tuberculosis. the similarities in the proportion of genes devoted to fatty acid degradation and to lipid biosynthesis was a striking but not surprising finding given the relatedness of these organisms and their success as intracellular pathogens. the rapid recent improvemen ... | 2003 | 12781482 |
| analysis of virulence plasmid gene expression of intra-macrophage and in vitro grown rhodococcus equi atcc 33701. | rhodococcus equi is a soil organism that infects macrophages of foals and immunocompromised humans. virulence in foal isolates is tightly associated with an 80kb plasmid, which includes a pathogenicity island (pi) with a virulence-associated gene family, vap. a dna microarray containing 66 of 69 putative open reading frames (orfs) of the virulence plasmid was developed. virulence plasmid gene expression of r. equi grown in macrophages or under different conditions in vitro was compared against i ... | 2003 | 12781484 |
| [unusual gram positive rods, causing pneumonia]. | in the last decade, a growing number of patients with pneumonia, caused by unusual gram positive rods have been observed. mostly, the patients had been infected as a consequence of impaired immunity. in some cases, bioterrorist activities may also induce pneumonia by gram positive rods (b. anthracis). in order to bring these organisms to the attention of the medical community, we present three clinical cases and describe six species of gram positive rods, known to provoke this kind of pneumonias ... | 2003 | 12784178 |
| relationship of demethylation processes to veratric acid concentration and cell density in cultures of rhodococcus erythropolis. | the aim of this study was to investigate the correlation between veratrate degradation, veratric acid concentration and cell density in rhodococcus erythropolis cultures. the optimum culture conditions for veratrate demethylation proved to be a cell density of a(660)=1 and a concentration of 0.02% veratrate. all the products of demethylation (i.e. vanillic and protocatechuic acids) were found to be present and correlated with the appearance of high levels of free radicals and formaldehyde after ... | 2003 | 12788048 |
| characterization of hydrocarbon-degrading microbial populations in contaminated and pristine alpine soils. | biodegradation of petroleum hydrocarbons in cold environments, including alpine soils, is a result of indigenous cold-adapted microorganisms able to degrade these contaminants. in the present study, the prevalence of seven genotypes involved in the degradation of n-alkanes (pseudomonas putida gpo1 alkb; acinetobacter spp. alkm; rhodococcus spp. alkb1, and rhodococcus spp. alkb2), aromatic hydrocarbons (p. putida xyle), and polycyclic aromatic hydrocarbons (p. putida ndob and mycobacterium sp. st ... | 2003 | 12788702 |
| cavitary pneumonia due to rhodococcus equi in a heart transplant recipient. | rhodococcus equi is an uncommon human pathogen that usually affects immunocompromised patients. we present a case of a 68-year-old male heart transplant recipient, who developed rhodococcal pneumonia with secondary bacteremia 10 months post-transplant. the patient was a retired carpenter who was involved in breeding of horses. he responded completely to the treatment with vancomycin and imipenem/cilastin, followed by oral ciprofloxacin and minocycline for total treatment duration of 5 months. th ... | 2003 | 12791074 |
| emergence of rifampin-resistant rhodococcus equi with several types of mutations in the rpob gene among aids patients in northern thailand. | the antimicrobial susceptibilities of 30 rhodococcus equi isolates obtained from 30 patients between 1993 and 2001 in northern thailand were investigated. the mics showed a tendency toward resistance to various antibiotics but sensitivity to imipenem, minocycline, vancomycin, and teicoplanin (mics, </=0.5 micro g/ml) and relative sensitivity to meropenem, clarithromycin, and ciprofloxacin (mics, </=2 micro g/ml). of the 30 isolates, 26 were susceptible (mics, </=1 micro g/ml), 1 showed low-level ... | 2003 | 12791846 |
| prognosis and clinical evaluation of infection caused by rhodococcus equi in hiv-infected patients: a multicenter study of 67 cases. | to assess the clinical characteristics and the factors that influenced the prognosis of patients with hiv and infection caused by rhodococcus equi. | 2003 | 12796176 |
| analyses of microbial desulfurization reaction of alkylated dibenzothiophenes dissolved in oil phase. | the kinetics of the oil/water two-phase reaction system was analyzed, and the reaction was carried out with the desulfurization of alkylated dibenzothiophenes (cx-dbts) using the desulfurizing microorganism mycobacterium sp. g3. in the water-phase reaction system, the desulfurization activities were constant with respect to species of cx-dbts as substrates. however, the desulfurization activities in the oil/water two-phase reaction system against dbt, 4,6-dimethyl dbt, 4,6-diethyl dbt, 4,6-dipro ... | 2003 | 12800143 |
| evidence of cytochrome p450-catalyzed cleavage of the ether bond of phenoxybutyrate herbicides in rhodococcus erythropolis k2-3. | bacterial strain rhodococcus erythropolis k2-3 can cleave the ether bond of the phenoxybutyrate herbicides, i.e., 4-(2,4-dichlorophenoxy)butyrate (2,4-db) and 4-(4-chloro-2-methylphenoxy)butyrate (mcpb), by an enzyme system that is constitutively expressed. the enzyme(s) involved were investigated in this study. the rate of disappearance of 2,4-db determined in a whole cell assay amounted to 0.6 mmol/h x g(dry mass). carbon monoxide difference spectra of dithionite-reduced whole cells and crude ... | 2003 | 12801099 |
| characterization of the iron-regulated desa promoter of streptomyces pilosus as a system for controlled gene expression in actinomycetes. | background: the bioavailability of iron is quite low since it is usually present as insoluble complexes. to solve the bioavailability problem microorganisms have developed highly efficient iron-scavenging systems based on the synthesis of siderophores that have high iron affinity. the systems of iron assimilation in microorganisms are strictly regulated to control the intracellular iron levels since at high concentrations iron is toxic for cells. streptomyces pilosus synthesizes the siderofore d ... | 2003 | 12801423 |
| purification and characterization of the aromatic desulfinase, 2-(2'-hydroxyphenyl)benzenesulfinate desulfinase. | 2-(2(')-hydroxyphenyl)benzenesulfinate desulfinase (hpbs desulfinase) catalyzes the cleavage of the carbon-sulfur bond of 2-(2(')-hydroxyphenyl)benzenesulfinate (hpbs) to form hydroxybiphenyl and sulfite. this is the final step in the desulfurization of dibenzothiophene, the organosulfur compound used to study biodesulfurization of petroleum middle distillate. hpbs desulfinase was purified 1600-fold from rhodococcus igts8. the purification was monitored using a spectrofluorimetric assay and sds- ... | 2003 | 12801508 |
| transformation of rhodococcus rhodnii, a symbiont of the chagas disease vector rhodnius prolixus, with integrative elements of the l1 mycobacteriophage. | elimination of vector populations through the use of insecticides is the principal means of controlling chagas disease. because of the limitations of insecticide use, we have been developing a new potential method of control, to be used in conjunction with insecticide programs, a method which utilizes genetically modified symbiotic bacteria. these transformed bacteria can express anti-parasitic agents in the gut of the bug where the trypanosomes also are found. previous studies have shown that i ... | 2003 | 12809804 |
| pathologic quiz case: a 15-year-old adolescent girl with a cavitary lesion in the lung. | | 2003 | 12823069 |
| a ph-indicator-based screen for hydrolytic haloalkane dehalogenase. | | 2003 | 12824585 |
| molecular characterization of dioxygenases from polycyclic aromatic hydrocarbon-degrading mycobacterium spp. | polycyclic aromatic hydrocarbon (pah)-degrading genes nida and nidb that encode the alpha and beta subunits of the aromatic ring-hydroxylating dioxygenase have been cloned and sequenced from mycobacterium vanbaalenii pyr-1 [khan et al., appl. environ microbiol. 67 (2001) 3577-3585]. in this study, the presence of nida and nidb in 12 other mycobacterium or rhodococcus strains was investigated. initially, all strains were screened for their ability to degrade pahs by a spray plate method, and for ... | 2003 | 12829283 |
| regioselective oxidation of xylene isomers by rhodococcus sp. strain dk17. | rhodococcus sp. strain dk17 is able to utilize a variety of monocyclic aromatic hydrocarbons, including benzene, phenol, toluene, and o-xylene, as growth substrates. although dk17 is unable to grow on m- and p-xylene, this strain could transform these two xylene isomers to some extent after induction by o-xylene. the major accumulating compounds formed during the degradation of m- and p-xylene by dk17 were isolated by high-pressure liquid chromatography and identified by gas chromatography-mass ... | 2003 | 12829288 |
| steady-state and pre-steady-state kinetic analysis of halopropane conversion by a rhodococcus haloalkane dehalogenase. | haloalkane dehalogenase from rhodococcus rhodochrous ncimb 13064 (dhaa) catalyzes the hydrolysis of carbon-halogen bonds in a wide range of haloalkanes. we examined the steady-state and pre-steady-state kinetics of halopropane conversion by dhaa to illuminate mechanistic details of the dehalogenation pathway. steady-state kinetic analysis of dhaa with a range of halopropanes showed that bromopropanes had higher k(cat) and lower k(m) values than the chlorinated analogues. the kinetic mechanism of ... | 2003 | 12834356 |
| a small cryptic plasmid from rhodococcus erythropolis: characterization and utility for gene expression. | exploration of metabolically diverse rhodococci is generally hampered by the lack of genetic tools. a small cryptic plasmid (pan12) isolated from rhodococcus erythropolis strain an12 was sequenced. plasmid pan12 encodes proteins that share homology to replication proteins and putative cell division proteins. based on in vitro transposon mutagenesis, we determined that the rep protein of pan12 is essential for plasmid replication in rhodococcus spp., and the putative cell division protein div is ... | 2003 | 12835922 |
| rapid identification of rhodococcus equi by a pcr assay targeting the choe gene. | the actinomycete rhodococcus equi is an important pathogen of horses and an emerging opportunistic pathogen of humans. identification of r. equi by classical bacteriological techniques is sometimes difficult, and misclassification of an isolate is not uncommon. we report here on a specific pcr assay for the rapid and reliable identification of r. equi. it is based on the amplification of a fragment of the choe gene encoding cholesterol oxidase. the choe-based pcr was assessed by using a panel of ... | 2003 | 12843070 |
| conversion of aliphatic 2-acetoxynitriles by nitrile-hydrolysing bacteria. | the enzymatic hydrolysis of the nitrile group of different 2-acetoxynitriles was investigated in order to obtain catalysts that chemoselectively hydrolyse nitriles in the presence of ester groups. the biotransformation of four 2-acetoxynitriles [2-acetoxybutenenitrile (abn), 2-acetoxyheptanenitrile (ahn), 2-acetoxy-2-(2-furyl)acetonitrile (afn), and 2-acetoxy-2,3,3-trimethylbutanenitrile (atmb)] by different bacterial strains that synthesise nitrilases or nitrile hydratases was studied. abn, ahn ... | 2003 | 12845494 |
| [bacteraemia in patients with hiv disease: aetiological spectrum and profile of antimicrobial susceptibility]. | a retrospective survey of non-opportunistic bacterial pathogens isolated from blood cultures of patients with hiv disease has been carried out for a 6-year period, and the antibiotic susceptibility of the 748 microorganisms cultured from 682 consecutive patients, has been evaluated. gram-positive organisms significantly prevailed over gram-negative ones, with staphylococcus aureus, coagulase-negative staphylococci, enterococcus faecalis, xantomonas maltophilia, salmonella and pseudomonas sp. as ... | 1997 | 12847308 |
| stereo- and regiospecific cis,cis-muconate cycloisomerization by rhodococcus rhodochrous n75. | cis,cis-muconate cycloisomerase was purified to homogeneity from cells of rhodococcus rhodochrous n75 grown at the expense of benzoate and p-toluate as the sole sources of carbon. a single cycloisomerase was found to be induced in this organism with no isoforms being detected when r. rhodochrous n75 was grown on either benzoate or p-toluate as the sole source of carbon. the enzyme is hexameric with a single subunit mr of 40,000. cis,cis-muconate cycloisomerase from r. rhodochrous n75 displayed s ... | 2003 | 12855164 |
| isolation and characterization of a transposon mutant of pseudomonas aeruginosa affecting uptake of dibenzothiophene in n-tetradecane. | isolation and characterization of a transposon mutant of pseudomonas aeruginosa affecting the uptake of dibenzothiophene (dbt) in n-tetradecane (n-td). | 2003 | 12859648 |
| color removal ability of a streptomycin resistant decolorizing strain rhodococcus erythropolis (atcc:4277.1). | rhodococcua erythropolis (atcc 4277.1) is a streptomycin resistant mutant of atcc 4277, which can decolorize the sulfonated azo dye of orange ii and amido black. pseudomonaes luteola is a decolorizing strain, which was isolated from sludge resulting from the treatment of dyeing wastewater. this study had two purposes: 1) to determine the color removal capacity of r. erythropolis (atcc 4277.1) for red 22, v2rp and rp2b dyes; and 2) to compare the decolorization capability of r. erythropolis (atcc ... | 2003 | 12862232 |
| effects of culture conditions on the mycolic acid composition of isolates of rhodococcus spp. from activated sludgefoams. | the influence of two different carbon sources and three incubation temperatures on the mycolic acid compositions of three rhodococcus isolates from activated sludge was examined using selective ion monitoring (sim) gas chromatography-mass spectrometry (gc-ms). considerable qualitative and quantitative differences were detected in the mycolic acid compositions of the three very closely related isolates grown under the same conditions. culture age also affected both the chain lengths and proportio ... | 2003 | 12866841 |
| cloning of a rhodococcal promoter using a transposon for dibenzothiophene biodesulfurization. | the expression of biodesulfurization genes (dsz) in rhodococcus erythropolis strain ka2-5-1 is repressed by sulfate which is the product of biodesulfurization. the application of a sulfate non-repressible promoter could be effective in enhancing biodesulfurization. a promoter-probe transposon was constructed using the promoterless, red-shifted green fluorescence protein gene (rsgfp). a 340 bp putative promoter element, designated kap1, was isolated from a strain ka2-5-1 recombinant that had show ... | 2003 | 12882585 |
| [bacterial infections in patients infected by hiv]. | individuals infected by the human immuno deficiency are more prone to suffering certain bacterial infections in the course of their clinical evolution. the agents involved in these infections are: streptococcus pneumoniae, haemophilus influenzae, pseudomonas aeruginosa, salmonella spp and campylobacter spp, which occasion an increase in morbidity and mortality. with a lower frequency, but with an equal morbidity and mortality, infections have been found caused by rhodococcus equi, nocardia spp a ... | 1998 | 12891392 |
| the thiocarbamate-inducible rhodococcus enzyme thcf as a member of the family of alpha/beta hydrolases with haloperoxidative side activity. | purified thiocarbamate-inducible thcf of rhodococcus erythropolis ni86/21, overexpressed in escherichia coli, displayed several characteristics of the hash family of enzymes that groups prokaryotic proteins of the alpha/beta hydrolase superfamily possessing serine-dependent hydrolase and/or haloperoxidase activity. kinetic analysis of bromination and ester hydrolysis revealed a low affinity of thcf for model substrates. sulfoxidation of thiocarbamates was demonstrated but probably represents a s ... | 2003 | 12892883 |
| novel bacteria degrading n-acylhomoserine lactones and their use as quenchers of quorum-sensing-regulated functions of plant-pathogenic bacteria. | bacteria degrading the quorum-sensing (qs) signal molecule n-hexanoylhomoserine lactone were isolated from a tobacco rhizosphere. twenty-five isolates degrading this homoserine lactone fell into six groups according to their genomic rep-pcr and rrs pcr-rflp profiles. representative strains from each group were identified as members of the genera pseudomonas, comamonas, variovorax and rhodococcus: all these isolates degraded n-acylhomoserine lactones other than the hexanoic acid derivative, albei ... | 2003 | 12904538 |
| degradation of car engine base oil by rhodococcus sp. ndkk48 and gordonia sp. ndky76a. | two microorganisms (ndkk48 and ndky76a) that degrade long-chain cyclic alkanes (c-alkanes) were isolated from soil samples. strains ndkk48 and ndky76a were identified as rhodococcus sp. and gordonia sp., respectively. both strains used not only normal alkane (n-alkane) but also c-alkane as a sole carbon and energy source, and the strains degraded more than 27% of car engine base oil (1% addition). | 2003 | 12913308 |
| microbiological transformation of benzene into phenol by cultured rhodococcus erythropolis 3/89 cells. | | 2001 | 12918356 |
| analysis of anamnestic immune responses in adult horses and priming in neonates induced by a dna vaccine expressing the vapa gene of rhodococcus equi. | rhodococcus equi remains one of the most important pathogens of early life in horses, yet conventional vaccines to prevent rhodococcal pneumonia have not been successful. dna vaccination offers an alternative to conventional vaccines with specific advantages for immunization of neonates. we developed a dna vaccine expressing the vapa gene (pvr1055vapa) that induced an anamnestic response characterized by virulence associated protein a (vapa)-specific igg antibodies in sera and bronchoalveolar la ... | 2003 | 12922115 |
| complete nucleotide sequence and genetic organization of the 210-kilobase linear plasmid of rhodococcus erythropolis bd2. | the complete nucleotide sequence of the linear plasmid pbd2 from rhodococcus erythropolis bd2 comprises 210,205 bp. sequence analyses of pbd2 revealed 212 putative open reading frames (orfs), 97 of which had an annotatable function. these orfs could be assigned to six functional groups: plasmid replication and maintenance, transport and metalloresistance, catabolism, transposition, regulation, and protein modification. many of the transposon-related sequences were found to flank the isopropylben ... | 2003 | 12923100 |
| nitrile biotransformations for the synthesis of enantiomerically enriched baylis-hillman adducts. | catalysed by the nitrile hydratase/amidase-containing rhodococcus sp. aj270 cells, a number of beta-aryl- and beta-alkyl- beta-hydroxy-alpha-methylenepropiononitriles (the baylis-hillman nitriles) 1 underwent hydrolysis under mild conditions to produce the corresponding enantiomerically enriched baylis-hillman amides 2 and acids 3. the enantioselectivity of the biotransformations was strongly determined by the steric effect of the substituents at the beta-position of the substrates. the protecti ... | 2003 | 12926256 |
| enantioselectivity of epoxide hydrolase catalysed oxirane ring opening: a 3d qsar study. | a 3d qsar analysis (quantitative structure activity relationships) of a set of 2,2-disubstituted epoxides, substrates for epoxide hydrolases originating from four different organisms, was conducted by comfa (comparative molecular field analysis) and comsia (comparative molecular similarity indices analysis), with respect to the enantioselective ring opening to the corresponding vicinal diol. structural variations of the substrates include alkyl chains of different lengths, unsaturated moieties ( ... | 2003 | 12926852 |
| effect of starvation on resuscitation and the surface characteristics of bacteria. | resuscitation behavior of bacteria after starvation for carbon and nitrogen was investigated. in addition effect of carbon and nitrogen starvation conditions on the surface characteristics and adhesive properties of bacteria were studied. two pure culture herbicide degrading bacteria were used in the study: pseudomonas sp. strain a, and rhodococcus corallinus strain 11. these bacteria are known to degrade cyanuric acid which is a derivative of s-triazine, a common herbicide used widely. selected ... | 2003 | 12929805 |
| cardiac tamponade in patients with human immunodeficiency virus disease. | the characteristics of cardiac tamponade in patients with human immunodeficiency virus (hiv) disease were examined by evaluating the cases, case series, and related articles, including autopsy series, identified through a comprehensive literature search. one-hundred eighty-five cases of cardiac tamponade have been reported in patients with hiv disease. sex data were available in 176 patients, of whom 154 (87%) were males. the mean age was 34.7 +/- 10.4 years (range, 11 months to 61 years). mean ... | 2003 | 12934767 |
| catalytic mechanism of the maloalkane dehalogenase linb from sphingomonas paucimobilis ut26. | haloalkane dehalogenases are bacterial enzymes capable of carbon-halogen bond cleavage in halogenated compounds. to obtain insights into the mechanism of the haloalkane dehalogenase from sphingomonas paucimobilis ut26 (linb), we studied the steady-state and presteady-state kinetics of the conversion of the substrates 1-chlorohexane, chlorocyclohexane, and bromocyclohexane. the results lead to a proposal of a minimal kinetic mechanism consisting of three main steps: (i) substrate binding, (ii) cl ... | 2003 | 12952988 |
| conversion of 2-fluoromuconate to cis-dienelactone by purified enzymes of rhodococcus opacus 1cp. | the present study describes the (19)f nuclear magnetic resonance analysis of the conversion of 3-halocatechols to lactones by purified chlorocatechol 1,2-dioxygenase (clca2), chloromuconate cycloisomerase (clcb2), and chloromuconolactone dehalogenase (clcf) from rhodococcus opacus 1cp grown on 2-chlorophenol. the 3-halocatechol substrates were produced from the corresponding 2-halophenols by either phenol hydroxylase from trichosporon cutaneum or 2-hydroxybiphenyl 3-mono-oxygenase from pseudomon ... | 2003 | 12957954 |
| virulence of rhodococcus equi isolated from cats and dogs. | nine cat isolates and nine dog isolates of rhodococcus equi from clinical material were investigated for the presence of the virulence-associated antigens (vapa and vapb) and virulence plasmids. five of the cat isolates and one dog isolate were vapa positive and contained an 85-kb type i or an 87-kb type i plasmid. the remaining 12 isolates were avirulent r. equi strains and contained no virulence plasmids. | 2003 | 12958297 |
| surviving the acid test: responses of gram-positive bacteria to low ph. | gram-positive bacteria possess a myriad of acid resistance systems that can help them to overcome the challenge posed by different acidic environments. in this review the most common mechanisms are described: i.e., the use of proton pumps, the protection or repair of macromolecules, cell membrane changes, production of alkali, induction of pathways by transcriptional regulators, alteration of metabolism, and the role of cell density and cell signaling. we also discuss the responses of listeria m ... | 2003 | 12966143 |
| recombinant pseudomonas putida carrying both the dsz and hcu genes can desulfurize dibenzothiophene in n-tetradecane. | pseudomonas putida ifo13696, a recombinant strain with dsz desulfurization genes, desulfurized dibenzothiophene (dbt) in water but not in n-tetradecane. by introducing into this recombinant strain the hcuabc genes that take part in the uptake of dbt in the oil phase into the cell, 82% of 1 mm dbt in n-tetradecane was degraded in 24 h by resting cells. the products of hcuabc genes thus acted in the uptake of dbt in n-tetradecane into the cells and were effective in desulfurization of dbt in the h ... | 2003 | 12967002 |
| residue 345 of dibenzothiophene (dbt) sulfone monooxygenase is involved in c-s bond cleavage specificity of alkylated dbt sulfones. | rhodococcus erythropolis igts8 that possesses dibenzothiophene sulfone monooxygenase mutated at residue 345 (q345a), can degrade octyl sulfide on which the wild strain cannot grow. residue 345 and the neighbouring residues were changed by site-directed mutagenesis. only dsza changed at residue 345 gave an altered c-s bond cleavage pattern of 3-methyl dbt sulfone. this residue is therefore involved in c-s bond cleavage specifically for alkylated dbt sulfone. | 2003 | 12967013 |
| a novel inhibitor for fe-type nitrile hydratase: 2-cyano-2-propyl hydroperoxide. | nitrile hydratase (nhase) is a non-heme iron or non-corrin cobalt enzyme having two post-translationally modified ligand residues, cysteine-sulfinic acid (alphacys112-so(2)h) and -sulfenic acid (alphacys114-soh). we studied the interaction between fe-type nhase and isobutyronitrile (iso-bn) which had been reported as a competitive inhibitor with a k(i) value of 5 microm. from detailed kinetic studies of the inhibitory effect of iso-bn on fe-type nhase, we found that authentic iso-bn was hydrated ... | 2003 | 13129355 |
| rhodococcus tukisamuensis sp. nov., isolated from soil. | a novel strictly aerobic, heterotrophic, mesophilic bacterium, strain mb8(t), was isolated from soil in sapporo city, hokkaido, japan. the g+c content of strain mb8(t) was 66.0 mol%. it had mycolic acids with 44-52 carbon atoms and c16 : 0 and c18 : 1 (9) as the major fatty acids. the major isoprenoid quinone was mk-8(h(2)). the cell wall contained meso-diaminopimelic acid, arabinose and galactose. 16s rdna, chemotaxonomic and morphological data indicated that this strain clearly belonged to the ... | 2003 | 13130015 |
| biological waste gas treatment with a modified rotating biological contactor. ii. effect of operating parameters on process performance and mathematical modeling. | in the first part of this paper, we introduced a modified rotating biological contactor (rbc) for the biological treatment of waste gas, and demonstrated its feasibility by applying the process to the biodegradation of toluene in a 91-liter reactor containing 20 biofilm support discs with a diameter of 40 cm [1]. we showed that the proposed system allows the unlimited growth of the biofilm to be suppressed, hence eliminating the risk of clogging associated with other biological waste gas treatme ... | 2003 | 14505166 |
| post-translational modification of rhodococcus r312 and comamonas ni1 nitrile hydratases. | nitrile hydratases (nhases) are industrially significant iron- and cobalt-containing enzymes used in the large-scale synthesis of acrylamide. previous reports have shown that the active site peptides of nhases are post-translationally modified by oxidation of cysteine residues, and that these modifications are essential for catalysis. we report mass spectrometric evidence of the oxidation states of the active site cysteines in the iron coordination spheres of two iron-containing nitrile hydratas ... | 2003 | 14505323 |
| deletion of vapa encoding virulence associated protein a attenuates the intracellular actinomycete rhodococcus equi. | virulent strains of the facultative intracellular bacterium rhodococcus equi isolated from young horses (foals) with r. equi pneumonia, carry an 80-90 kb virulence plasmid and express a highly immunogenic 15-17 kda protein of unknown function called vapa (virulence associated protein a). recent sequencing of the virulence plasmid identified a putative pathogenicity island encoding a novel family of seven vap proteins including vapa. these proteins exhibit a significant sequence similarity to eac ... | 2003 | 14507368 |
| scale-down studies on the hydrodynamics of two-liquid phase biocatalytic reactors. | the maintenance of constant interfacial area per unit volume is a key parameter for the successful scale-up of two-liquid phase bioconversion processes. to date, however, there is little published information on the hydrodynamics of such systems and a suitable basis for scale-up has yet to be defined and verified. here we report power input and hydrodynamic data for a whole-cell bioconversion process using resting cells of rhodococcus r312 to catalyse the hydration of a poorly water-soluble subs ... | 2002 | 14508672 |
| enhanced desulfurization in a transposon-mutant strain of rhodococcus erythropolis. | the dsz desulfurization gene cluster from rhodococcus erythropolis strain ka2-5-1 was transferred into r. erythropolis strain mc1109, unable to desulfurize light gas oil (lgo), using a transposon-transposase complex. as a result, two recombinant strains, named mc0203 and mc0122, were isolated. resting cells of strain mc0203 decreased the sulfur concentration of lgo from 120 mg l(-1) to 70 mg l(-1) in 2 h. the lgo-desulfurization activity of strain mc0203 was about twice that of strain mc0122 and ... | 2003 | 14514056 |
| a self-sufficient cytochrome p450 with a primary structural organization that includes a flavin domain and a [2fe-2s] redox center. | p450 rhf from rhodococcus sp. ncimb 9784 is the first example of a new class of cytochrome p450 in which electrons are supplied by a novel, fmn- and fe/s-containing, reductase partner in a fused arrangement. we have previously cloned the gene encoding the enzyme and shown it to comprise an n-terminal p450 domain fused to a reductase domain that displays similarity to the phthalate family of oxygenase reductase proteins. a reductase of this type had never previously been reported to interact with ... | 2003 | 14514666 |
| in vitro antimicrobial activity of moxifloxacin compared to other quinolones against recent clinical bacterial isolates from hospitalized and community-based cancer patients. | the in vitro spectrum of moxifloxacin (a c-8-methoxyquinolone) was compared to that of ciprofloxacin and levofloxacin against 924 recent clinical isolates from cancer patients. moxifloxacin was more active than the comparator agents against gram-positive pathogens, with potent activity against aerococcus spp., listeria monocytogenes, micrococcus spp., rhodococcus equi, and stomatococcus mucilaginous, methicillin-susceptible staphylococcus spp., all beta hemolytic streptococci, viridans streptoco ... | 2003 | 14522520 |
| degradation of alkanes and highly chlorinated benzenes, and production of biosurfactants, by a psychrophilic rhodococcus sp. and genetic characterization of its chlorobenzene dioxygenase. | rhodococcus sp. strain ms11 was isolated from a mixed culture. it displays a diverse range of metabolic capabilities. during growth on 1,2,4-trichlorobenzene, 1,2,4,5-tetrachlorobenzene (1,2,4,5-tecb) and 3-chlorobenzoate stoichiometric amounts of chloride were released. it also utilized all three isomeric dichlorobenzenes and 1,2,3-trichlorobenzene as the sole carbon and energy source. furthermore, the bacterium grew well on a great number of n-alkanes ranging from n-heptane to n-triacontane an ... | 2003 | 14523120 |
| [the quantity and structure of the root-associated microbial complexes of two greenhouse rose cultivars]. | the study of the root-associated microbial complexes of affected and healthy rose plants of two cultivars (grand gala and royal velvet) grown in a greenhouse showed that the biomass of eukaryotic microorganisms in the rhizoplane and rhizosphere of healthy rose plants and in the surrounding soil was considerably lower than in the same loci of affected plants. in contrast, the biomass of root-associated prokaryotic microorganisms was higher in the case of healthy than in the case of affected rose ... | 2003 | 14526548 |
| protonation structures of cys-sulfinic and cys-sulfenic acids in the photosensitive nitrile hydratase revealed by fourier transform infrared spectroscopy. | nitrile hydratase (nhase) from rhodococcus n-771, which catalyzes hydration of nitriles to the corresponding amides, exhibits novel photosensitivity; in the dark, it is in the inactive form that binds an endogenous nitric oxide (no) molecule at the non-heme iron center, and photodissociation of the no activates the enzyme. nhase is also known to have a unique active site structure. two cysteine ligands to the iron center, alphacys112 and alphacys114, are post-translationally modified to sulfinic ... | 2003 | 14529274 |
| crystallization of the terminal oxygenase component of biphenyl dioxygenase derived from rhodococcus sp. strain rha1. | the terminal oxygenase component of the biphenyl dioxygenase (bpha1a2 complex) was over-expressed with a novel over expression system in recombinant rhodococcus strain and purified. the purified enzyme has been crystallized by the hanging drop vapor diffusion method and subjected to x-ray diffraction analysis. the crystals belong to the tetragonal system in the space group p4(1)2(1)2 or p4(3)2(1)2 and diffract to better than 2.2a resolution. | 2003 | 14529495 |
| diversity of nitrile hydratase and amidase enzyme genes in rhodococcus erythropolis recovered from geographically distinct habitats. | a molecular screening approach was developed in order to amplify the genomic region that codes for the alpha- and beta-subunits of the nitrile hydratase (nhase) enzyme in rhodococci. specific pcr primers were designed for the nhase genes from a collection of nitrile-degrading actinomycetes, but amplification was successful only with strains identified as rhodococcus erythropolis. a hydratase pcr product was also obtained from r. erythropolis dsm 43066(t), which did not grow on nitriles. southern ... | 2003 | 14532022 |
| substrate preferences in biodesulfurization of diesel range fuels by rhodococcus sp. strain ecrd-1. | the range of sulfur compounds in fuel oil and the substrate range and preference of the biocatalytic system determine the maximum extent to which sulfur can be removed by biodesulfurization. we show that the biodesulfurization apparatus in rhodococcus sp. strain ecrd-1 is able to attack all isomers of dibenzothiophene including those with at least four pendant carbons, with a slight preference for those substituted in the alpha-position. with somewhat less avidity, this apparatus is also able to ... | 2003 | 14532032 |
| distribution of the coenzyme m pathway of epoxide metabolism among ethene- and vinyl chloride-degrading mycobacterium strains. | an epoxyalkane:coenzyme m (com) transferase (eacomt) enzyme was recently found to be active in the aerobic vinyl chloride (vc) and ethene assimilation pathways of mycobacterium strain js60. in the present study, eacomt activity and genes were investigated in 10 different mycobacteria isolated on vc or ethene from diverse environmental samples. in all cases, epoxyethane metabolism in cell extracts was dependent on com, with average specific activities of eacomt between 380 and 2,910 nmol/min/mg o ... | 2003 | 14532060 |
| nitrile hydrolysing activities of deep-sea and terrestrial mycolate actinomycetes. | nitrile metabolising actinomycetes previously recovered from deep-sea sediments and terrestrial soils were investigated for their nitrile transforming properties. metabolic profiling and activity assays confirmed that all strains catalysed the hydrolysis of nitriles by a nitrile hydratase/amidase system. acetonitrile and benzonitrile, when used as growth substrates for enzyme induction experiments, had a significant influence on the biotransformation activities towards various nitriles and amide ... | 2003 | 14533712 |
| rhodococcus equi and genetic susceptibility: assessing transferrin genotypes from paraffin-embedded tissues. | rhodococcus equi is a bacterial pathogen, ubiquitous in the soil, that infects many foals and is lethal to some. transferrin is an iron-binding protein that has bacteriostatic properties in the blood. transferrin is also highly polymorphic in most species, with 15 variants identified for horses using biochemical methods, and may be responsible for variation in susceptibility to bacterial pathogens. the objectives of this study were 1) to compare biochemical typing with dna typing of transferrin, ... | 2003 | 14535549 |
| evolution of the soluble diiron monooxygenases. | based on structural, biochemical, and genetic data, the soluble diiron monooxygenases can be divided into four groups: the soluble methane monooxygenases, the amo alkene monooxygenase of rhodococcus corallinus b-276, the phenol hydroxylases, and the four-component alkene/aromatic monooxygenases. the limited phylogenetic distribution of these enzymes among bacteria, together with available genetic evidence, indicates that they have been spread largely through horizontal gene transfer. phylogeneti ... | 2003 | 14550940 |
| a gene cluster responsible for alkylaldoxime metabolism coexisting with nitrile hydratase and amidase in rhodococcus globerulus a-4. | an enzyme "alkylaldoxime dehydratase (oxdrg)" was purified and characterized from rhodococcus globerulus a-4, in which nitrile hydratase (nhase) and amidase coexisted with the enzyme. the enzyme contains heme b as a prosthetic group, requires reducing reagents for the reaction, and is most active at a neutral ph and at around 30 degrees c, similar to the phenylacetaldoxime dehydratase from bacillus sp. oxb-1 (oxdb). however, some differences were seen in subunit structure, substrate specificity, ... | 2003 | 14556637 |
| development of a conductimetric biosensor using immobilised rhodococcus ruber whole cells for the detection and quantification of acrylonitrile. | a conductimetric biosensor for the detection of acrylonitrile in solution was designed and characterised using whole cells of rhodococcus ruber ncimb 40757, which were immobilised into a disc of dimethyl silicone sponge (immobasil). the biosensor described was capable of the detection and quantification of acrylonitrile in aqueous solution, having a linear response to concentrations between 2 and 50 mm (106-2650 ppm) acrylonitrile. the biosensor has been shown to be reproducible with respect to ... | 2003 | 14559001 |
| involvement of nitric oxide synthase in sucrose-enhanced hydrogen peroxide tolerance of rhodococcus sp. strain apg1, a plant-colonizing bacterium. | hydrogen peroxide (h2o2) tolerance of rhodococcus sp. strain apg1, previously isolated from the aquatic fern azolla pinnata, was examined in relation to nitric oxide (no) production by cells cultured on a variety of c sources. cells inoculated onto a. pinnata fronds established a surface-sterilant resistant density of 2-4x10(7) cells g(-1) without causing disease. compared to cultures containing glucose, fructose, mannitol, or glycerol, those provided only with sucrose displayed, on a per c basi ... | 2003 | 14559426 |
| biological waste gas treatment with a modified rotating biological contactor. iota. control of biofilm growth and long-term performance. | in this work, we introduce a modified rotating biological contactor (rbc) system and demonstrate its feasibility by applying the newly devised process to the biological treatment of artificial waste gas. in the proposed system, the waste gas is introduced to the bioreactor in the spacings between the rotating discs through a hollow shaft, thus allowing for intimate gas-liquid contact. a 91-l modified rbc containing 20 biofilm support discs 40 cm in diameter was used in the experiments. toluene w ... | 2003 | 14564499 |
| motif cxcc in nitrile hydratase activator is critical for nhase biogenesis in vivo. | nitrile hydratase (nhase) activator from rhodococcus sp. n-771 is required for nhase functional expression. the motif 73cxcc76 in the nhase activator sequence was here revealed to be vital for its function by site-directed mutagenesis. all three substitutions of the cysteines by serines resulted in a much lower level of expression of active nhase. furthermore, interaction between nhase activator and nhase was detected and the critical role of nhase activator was not exhibited in the cysteine oxi ... | 2003 | 14572657 |
| rhodococcus equi secreted antigens are immunogenic and stimulate a type 1 recall response in the lungs of horses immune to r. equi infection. | rhodococcus equi is an opportunistic pathogen in immunocompromised humans and an important primary pathogen in young horses. although r. equi infection can produce life-threatening pyogranulomatous pneumonia, most foals develop a protective immune response that lasts throughout life. the antigen targets of this protective response are currently unknown; however, mycobacterium tuberculosis is a closely related intracellular pathogen and provides a model system. based on previous studies of m. tub ... | 2003 | 14573652 |
| the rhodococcus sp. cocaine esterase: a bacterial candidate for novel pharmacokinetic-based therapies for cocaine abuse. | cocaine is a powerful central nervous stimulant and among the most abused of drugs. despite decades of efforts, however, no effective pharmacological treatments are available against cocaine addiction or toxic effects. classical receptor-antagonist therapeutic approaches have not yielded significant effects, although cocaine targets are well known, thus fostering development of alternative therapeutic strategies. recent evidence indicates that a sensible approach for treatment of cocaine abuse c ... | 2003 | 14584590 |
| isopropanol and acetone induces vinyl chloride degradation in rhodococcus rhodochrous. | in situ bioremediation of vinyl chloride (vc)-contaminated waste sites requires a microorganism capable of degrading vc. while propane will induce an oxygenase to accomplish this goal, its use as a primary substrate in bioremediation is complicated by its flammability and low water solubility. this study demonstrates that two degradation products of propane, isoproponal and acetone, can induce the enzymes in rhodococcus rhodochrous that degrade vc. additionally, a reasonable number of cells for ... | 2003 | 14605909 |
| analysis of bacterial dna patterns--an approach for controlling biotechnological processes. | optimisation of biotechnological processes catalysed by microbial cells requires detailed information about operational limits of the single cells. their performance is correlated with distinct physiological states. we related these states to cell cycle events, which were found to proceed extremely diversely in different bacterial strains. characteristic dna patterns were found flow cytometrically, depending on the type of strain, substrates and growth conditions involved; this information can b ... | 2003 | 14607431 |
| effects of iron modulation on growth and viability of rhodococcus equi and expression of virulence-associated protein a. | to determine the importance of iron for in vitro growth of rhodococcus equi, define potential iron sources in the environment and mechanisms by which r equi may obtain iron from the environment, and assess expression and immunogenicity of iron-regulated proteins. | 2003 | 14620767 |