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detection of bacterial virulence genes by subtractive hybridization: identification of capsular polysaccharide of burkholderia pseudomallei as a major virulence determinant.burkholderia pseudomallei, the etiologic agent of melioidosis, is responsible for a broad spectrum of illnesses in humans and animals particularly in southeast asia and northern australia, where it is endemic. burkholderia thailandensis is a nonpathogenic environmental organism closely related to b. pseudomallei. subtractive hybridization was carried out between these two species to identify genes encoding virulence determinants in b. pseudomallei. screening of the subtraction library revealed a ...200111119486
legionella pneumophila major acid phosphatase and its role in intracellular infection.legionella pneumophila is an intracellular pathogen of protozoa and alveolar macrophages. this bacterium contains a gene (pild) that is involved in both type iv pilus biogenesis and type ii protein secretion. we previously demonstrated that the pild prepilin peptidase is crucial for intracellular infection by l. pneumophila and that the secreted pild-dependent proteins include a metalloprotease, an acid phosphatase, an esterase/lipase, a phospholipase a, and a p-nitrophenyl phosphorylcholine hyd ...200111119504
clonal associations among staphylococcus aureus isolates from various sites of infection.a molecular epidemiological analysis was undertaken to identify lineages of staphylococcus aureus that may be disproportionately associated with infection. pulsed-field gel electrophoresis analysis of 405 s. aureus clinical isolates collected from various infection types and geographic locations was performed. five distinct s. aureus lineages (sals 1, 2, 4, 5, and 6) were identified, which accounted for 19.01, 9.14, 22.72, 10.12, and 4.69% of isolates, respectively. in addition, 85 lineages whic ...200111119523
actinobacillus pleuropneumoniae iron transport and urease activity: effects on bacterial virulence and host immune response.actinobacillus pleuropneumoniae, a porcine respiratory tract pathogen, has been shown to express transferrin-binding proteins and urease during infection. both activities have been associated with virulence; however, their functional role for infection has not yet been elucidated. we used two isogenic a. pleuropneumoniae single mutants (deltaexbb and deltaurec) and a newly constructed a. pleuropneumoniae double (deltaurec deltaexbb) mutant in aerosol infection experiments. neither the a. pleurop ...200111119539
identification and characterization of bipa, a bordetella bvg-intermediate phase protein.the bordetella bvgas sensory transduction system has traditionally been viewed as controlling a transition between two distinct phenotypic phases: the bvg(+) or virulent phase and the bvg(-) or avirulent phase. recently, we identified a phenotypic phase of bordetella bronchiseptica that displays reduced virulence in a rat model of respiratory infection concomitant with increased ability to survive nutrient deprivation. characterization of this phase, designated bvg-intermediate (bvg(i)), indicat ...200111123689
transcriptional activation of bordetella alcaligin siderophore genes requires the alcr regulator with alcaligin as inducer.genetic and biochemical studies have established that fur and iron mediate repression of bordetella alcaligin siderophore system (alc) genes under iron-replete nutritional growth conditions. in this study, transcriptional analyses using bordetella chromosomal alc-lacz operon fusions determined that maximal alc gene transcriptional activity under iron starvation stress conditions is dependent on the presence of alcaligin siderophore. mutational analysis and genetic complementation confirmed that ...200111133941
evaluation of 5' nuclease assay for detection of actinobacillus pleuropneumoniae.sequence detection by the 5' nuclease taqman assay uses online detection of internal fluorogenic probes in closed pcr tubes. primers and probe were chosen from a part of the omla gene common to all serotypes of actinobacillus pleuropneumoniae, which gave an amplicon of 92 bp. the test was evaluated with 73 lung isolates and 120 tonsil isolates of a. pleuropneumoniae as well as with a collection of reference strains. by using a c(t) value (cycle number in which the fluorescence exceeds the thresh ...200111136780
the crystal structure of the ttcsaa protein: an export-related chaperone from thermus thermophilus.the csaa protein was first characterized in bacillus subtilis as a molecular chaperone with export-related activities. here we report the 2.0 angstrom-resolution crystal structure of the thermus thermophilus csaa protein, designated ttcsaa. atomic structure and experiments in solution revealed a homodimer as the functional unit. the structure of the ttcsaa monomer is reminiscent of the well known oligonucleotide-binding fold, with the addition of extensions at the n- and c-termini that form an e ...200111157762
novel genes affecting urease acivity in actinobacillus pleuropneumoniae.characterization of a series of urease-negative transposon mutations of actinobacillus pleuropneumoniae revealed that many of the mutants had insertions 2 to 4 kbp upstream of the urease gene cluster. a 5-kbp upstream region of dna was sequenced and found to contain six open reading frames (orfs) transcribed in the same orientation as the urease genes. as well, a partial orf, apur, 202 bp upstream of these six orfs, is transcribed in the opposite orientation. the predicted product of this partia ...200111157936
relatedness of streptococcus suis isolates of various serotypes and clinical backgrounds as evaluated by macrorestriction analysis and expression of potential virulence traits.we evaluated the genetic diversity of streptococcus suis isolates of different serotypes by macrorestriction analysis and elucidated possible relationships between the genetic background, expression of potential virulence traits, and source of isolation. virulence traits included expression of serotype-specific polysaccharides, muramidase-released protein (mrp), extracellular protein factor (ef), hemolysin activity, and adherence to epithelial cells. macrorestriction analysis of streptococcal dn ...200111158088
fate of mycobacterium tuberculosis within murine dendritic cells.the interaction of microbes with dendritic cells (dcs) is likely to have an enormous impact on the initiation of the immune response against a pathogen. in this study, we compared the interaction of mycobacterium tuberculosis with murine bone marrow-derived dcs and macrophages (m phi) in vitro. m. tuberculosis grew equally well within nonactivated dcs and m phi. activation of dcs and m phi with gamma interferon and lipopolysaccharide inhibited the growth of the intracellular bacteria in a nitric ...200111159971
bronchitis caused by bordetella bronchiseptica in an elderly woman. 200011168091
the insect endosymbiont sodalis glossinidius utilizes a type iii secretion system for cell invasion.sodalis glossinidius is a maternally transmitted secondary endosymbiont residing intracellularly in tissues of the tsetse flies, glossina spp. in this study, we have used tn5 mutagenesis and a negative selection procedure to derive a s. glossinidius mutant that is incapable of invading insect cells in vitro and is aposymbiotic when microinjected into tsetse. this mutant strain harbors tn5 integrated into a chromosomal gene sharing high sequence identity with a type iii secretion system invasion ...200111172045
studies on diagnostic applications of egg yolk antibodies against bordetella bronchiseptica.the present paper describes the methods for producing egg yolk antibodies against bordetella bronchiseptica. in comparative experiments, avian and mammalian antibodies were applicated in diagnostic test systems. the results of these investigations show the possibility of substituting mammalian antibodies for igy in enzyme immunoassay and indirect immunofluorescence.199611178477
novel genetic and phenotypic heterogeneity in bordetella bronchiseptica pertactin.the bordetella bronchiseptica outer membrane protein pertactin is believed to function as an adhesin and is an important protective immunogen. previous sequence analysis of the pertactin gene identified two regions predicted to encode amino acid repeat motifs. recent studies have documented dna sequence heterogeneity in both regions. the present study describes additional variants in these regions, which form the basis for six novel pertactin types. immunoblotting demonstrated phenotypic heterog ...200111179374
effect of vaccination on experimental infection with bordetella bronchiseptica in dogs.to determine comparative efficacy of vaccines administered im and intranasally, used alone or sequentially, to protect puppies from infection with bordetella bronchiseptica and determine whether systemic or mucosal antibody response correlated with protection.200111201562
mobilization function of the pbhr1 plasmid, a derivative of the broad-host-range plasmid pbbr1.the pbhr1 plasmid is a derivative of the small (2.6-kb), mobilizable broad-host-range plasmid pbbr1, which was isolated from the gram-negative bacterium bordetella bronchiseptica (r. antoine and c. locht, mol. microbiol. 6:1785-1799, 1992). plasmid pbbr1 consists of two functional cassettes and presents sequence similarities with the transfer origins of several plasmids and mobilizable transposons from gram-positive bacteria. we show that the mob protein specifically recognizes a 52-bp sequence ...200111222611
variation in bordetella bronchiseptica flaa does not correlate with typing by macro-restriction analysis by pulsed-field gel electrophoresis.a genotyping method based on pcr-rflp analysis of the flagellin gene (flaa) was applied to 30 mainly feline isolates of bordetella bronchiseptica. these isolates were separated into three pcr-rflp groups with the restriction endonucleases haeiii, mspi, mboi and rsai. flaa nucleotide sequences representing each of the three groups differed from each other by 11-13%. one of the groups exhibited far greater flaa sequence identity with the cryptic flagellin gene sequence of b. pertussis (>97%) than ...200111232772
sira orthologs affect both motility and virulence.the sira gene of salmonella enterica serovar typhimurium encodes a two-component response regulator of the fixj family that has a positive regulatory influence on the expression of type iii secretion genes involved with epithelial cell invasion and the elicitation of bovine gastroenteritis. sira orthologs in pseudomonas, vibrio, and erwinia control the expression of distinct virulence genes in these genera, but an evolutionarily conserved target of sira regulation has never been identified. in t ...200111244064
pseudomonas stutzeri has two closely related pila genes (type iv pilus structural protein) with opposite influences on natural genetic transformation.pseudomonas stutzeri has type iv pili for which the pila gene (here termed pilai) provides the structural protein and which are required for dna uptake and natural genetic transformation. downstream of pilai we identified a gene, termed pilaii, coding for a deduced protein with a size similar to that of pilai with 55% amino acid sequence identity and with a typical leader peptide including a leader peptidase cleavage site. fusions to lacz revealed that pilaii is expressed only about 10% compared ...200111244078
differential regulation of bvg-activated virulence factors plays a role in bordetella pertussis pathogenicity.bordetella pertussis, the causative agent of whooping cough, regulates expression of many virulence factors via a two-component signal transduction system encoded by the bvgas regulatory locus. it has been shown by transcription activation kinetics that several of the virulence factors are differentially regulated. fha is transcribed within 10 min following a bvgas-inducing signal, while prn is transcribed after 1 h and ptx is not transcribed until 2 to 4 h after induction. these genes therefore ...200111254549
epitope mapping of monoclonal antibodies capable of neutralizing cytotoxic necrotizing factor type 1 of uropathogenic escherichia coli.cytotoxic necrotizing factor type 1 (cnf1) of uropathogenic escherichia coli belongs to a family of bacterial toxins that target the small gtp-binding rho proteins that regulate the actin cytoskeleton. members of this toxin family typically inactivate rho; however, cnf1 and the highly related cnf2 activate rho by deamidation. other investigators have reported that the first 190 amino acids of cnf1 constitute the cellular binding domain and that the cnf1 enzymatic domain lies within a 300-amino-a ...200111254559
reduced virulence of a bordetella bronchiseptica siderophore mutant in neonatal swine.one means by which bordetella bronchiseptica scavenges iron is through production of the siderophore alcaligin. a nonrevertible alcaligin mutant derived from the virulent strain 4609, designated dbb25, was constructed by insertion of a kanamycin resistance gene into alca, one of the genes essential for alcaligin biosynthesis. the virulence of the alca mutant in colostrum-deprived, caesarean-delivered piglets was compared with that of the parent strain in two experiments. at 1 week of age, piglet ...200111254568
proinflammatory and proapoptotic activities associated with bordetella pertussis filamentous hemagglutinin.filamentous hemagglutinin (fha) is a dominant cell surface-associated bordetella pertussis adhesin. recognition that this protein is secreted in significant amounts and that bacterial adhesins may have other activities, prompted an assessment of fha effects on human macrophages. incubation of human macrophage-like u937 cells with preparations of fha resulted in dose-dependent cytotoxicity, with death of 95% of treated cells after 24 h. based on the use of four independent methods, death of these ...200111254631
genetic organization of the region encoding regulation, biosynthesis, and transport of rhizobactin 1021, a siderophore produced by sinorhizobium meliloti.eight genes have been identified that function in the regulation, biosynthesis, and transport of rhizobactin 1021, a hydroxamate siderophore produced under iron stress by sinorhizobium meliloti. the genes were sequenced, and transposon insertion mutants were constructed for phenotypic analysis. six of the genes, named rhbabcdef, function in the biosynthesis of the siderophore and were shown to constitute an operon that is repressed under iron-replete conditions. another gene in the cluster, name ...200111274118
comparison of nucleic acid amplification, serology, and microbiologic culture for diagnosis of rhodococcus equi pneumonia in foals.recently, a technique was described for amplification of rhodococcus equi-specific chromosomal and vapa dna from blood and tracheal wash fluids. it was hypothesized that this technique would be more sensitive than standard culture techniques or serology for diagnosis of r. equi pneumonia in foals. tracheal wash fluid, nasal swabs, whole blood samples, and serum samples from 56 foals with pneumonia were analyzed. final clinical diagnosis was determined by the attending clinician on the basis of f ...200111283043
expression of the putative siderophore receptor gene bfrz is controlled by the extracytoplasmic-function sigma factor bupi in bordetella bronchiseptica.a new gene from bordetella bronchiseptica, bfrz encoding a putative siderophore receptor, was identified in a fur-repressor titration assay. a bfrz null mutant was constructed by allelic exchange. the protein profile of this mutant is similar to that of the wild-type parent strain. the bfrz(-)-bfrz(+) isogenic pair was tested for utilization of 132 different siderophores as iron sources. none of these iron sources acted as a ligand for bfrz. translational bfrz::phoa and transcriptional bfrz::lac ...200111292812
isolation and characterization of four bactericidal domains in the bovine beta-lactoglobulin.proteolytic digestion of bovine beta-lactoglobulin by trypsin yielded four peptide fragments with bactericidal activity. the peptides were isolated and their sequences were found as follows: vagtwy (residues 15-20), aasdislldaqsaplr (residues 25-40), ipavfk (residues 78-83) and vlvldtdyk (residues 92-100). the four peptides were synthesized and found to exert bactericidal effects against the gram-positive bacteria only. in order to understand the structural requirements for antibacterial activit ...200111325534
effects of intranasal inoculation with bordetella bronchiseptica, porcine reproductive and respiratory syndrome virus, or a combination of both organisms on subsequent infection with pasteurella multocida in pigs.to determine effects of intranasal inoculation with porcine reproductive and respiratory syndrome virus (prrsv) or bordetella bronchiseptica on challenge with nontoxigenic pasteurella multocida in pigs.200111327458
the adenylate cyclase toxin of bordetella pertussis binds to target cells via the alpha(m)beta(2) integrin (cd11b/cd18).the adenylate cyclase toxin (cyaa) of bordetella pertussis is a major virulence factor required for the early phases of lung colonization. it can invade eukaryotic cells where, upon activation by endogenous calmodulin, it catalyzes the formation of unregulated camp levels. cyaa intoxication leads to evident toxic effects on macrophages and neutrophils. here, we demonstrate that cyaa uses the alpha(m)beta(2) integrin (cd11b/cd18) as a cell receptor. indeed, the saturable binding of cyaa to the su ...200111342588
identification and functional characterization of arylamine n-acetyltransferases in eubacteria: evidence for highly selective acetylation of 5-aminosalicylic acid.arylamine n-acetyltransferase activity has been described in various bacterial species. bacterial n-acetyltransferases, including those from bacteria of the gut flora, may be involved in the metabolism of xenobiotics, thereby exerting physiopathological effects. we characterized these enzymes further by steady-state kinetics, time-dependent inhibition, and dna hybridization in 40 species, mostly from the human intestinal microflora. we report for the first time n-acetyltransferase activity in 11 ...200111344150
a case-control study of respiratory disease in thoroughbred racehorses in sydney, australia.in order to investigate the role of infectious agents in the aetiology of lower respiratory tract disease in thoroughbred racehorses, a matched case-control study was conducted. cases were identified by the presence of coughing, and were compared to a control population matched on time of sample collection and location within the same training establishment. tracheal wash samples were collected from 100 cases and 148 controls. case horses were more likely than controls to have endoscopic and cyt ...200111352347
activity and postantibiotic effect of marbofloxacin, enrofloxacin, difloxacin and ciprofloxacin against feline bordetella bronchiseptica isolates.the minimum inhibitory concentration (mic) and postantibiotic effect (pae) of marbofloxacin, enrofloxacin, difloxacin and ciprofloxacin were evaluated in vitro against 43 feline-source bordetella bronchiseptica strains. all strains tested were susceptible to marbofloxacin and enrofloxacin (mic90 0.5mg/l), while 93 and 84% of the strains were susceptible, respectively, to ciprofloxacin and difloxacin with mic(90) values of, respectively, 1 and 8mg/l. the pae was studied in 10 strains by exposure ...200111356321
diversity in the bordetella virulence regulon: transcriptional control of a bvg-intermediate phase gene.the bvgas signal transduction system controls the expression of at least three distinct phenotypic phases that lie along a continuum of gene expression states. the bvg+ phase is characterized by the expression of adhesins and toxins, whereas the bvg- phase is characterized by motility in bordetella bronchiseptica and the expression of vrg loci in bordetella pertussis. the bvg-intermediate (bvgi) phase is characterized by the absence of bvg-repressed phenotypes, the expression of some, but not al ...200111359572
ralstonia solanacearum needs motility for invasive virulence on tomato.ralstonia solanacearum, a widely distributed and economically important plant pathogen, invades the roots of diverse plant hosts from the soil and aggressively colonizes the xylem vessels, causing a lethal wilting known as bacterial wilt disease. by examining bacteria from the xylem vessels of infected plants, we found that r. solanacearum is essentially nonmotile in planta, although it can be highly motile in culture. to determine the role of pathogen motility in this disease, we cloned, charac ...200111371523
polysaccharide biosynthesis locus required for virulence of bacteroides fragilis.bacteroides fragilis, though only a minor component of the human intestinal commensal flora, is the anaerobe most frequently isolated from intra-abdominal abscesses. b. fragilis 9343 expresses at least three capsular polysaccharides-polysaccharide a (ps a), ps b, and ps c. purified ps a and ps b have been tested in animal models and are both able to induce the formation of intra-abdominal abscesses. mutants unable to synthesize ps b or ps c still facilitate abscess formation at levels comparable ...200111401972
brucella abortus cyclic beta-1,2-glucan mutants have reduced virulence in mice and are defective in intracellular replication in hela cells.null cyclic beta-1,2-glucan synthetase mutants (cgs mutants) were obtained from brucella abortus virulent strain 2308 and from b. abortus attenuated vaccinal strain s19. both mutants show greater sensitivity to surfactants like deoxycholic acid, sodium dodecyl sulfate, and zwittergent than the parental strains, suggesting cell surface alterations. although not to the same extent, both mutants display reduced virulence in mice and defective intracellular multiplication in hela cells. the b. abort ...200111401996
the pathological effect of the bordetella dermonecrotic toxin in mice.the effect of dermonecrotic toxin (dnt) expression of bordetella bronchiseptica was studied in mice by comparing the pathology induced by a wild type strain with that induced by an isogenic dnt- strain in which part of the structural gene has been replaced by an antibiotic resistance cassette. while extracts of strain b58 proved toxic in intravenously inoculated mice, similar extracts from strain b58gp had lost toxic activity. the parent (b58) and the mutant (b58gp) strains of b. bronchiseptica ...200011402657
use of temporal temperature gradient gel electrophoresis to identify flaa and fim3 sequence types in bordetella bronchiseptica.the aim of this study was to develop an approach to detect variation in the flaa and fim3 genes amongst animal isolates of bordetella bronchiseptica using temporal temperature gradient gel electrophoresis (ttge).200111412348
[bordetella bronchiseptica infection in a senegalese hiv positive patient: carrier state or illness?]. 200111413848
the bordetella bhu locus is required for heme iron utilization.bordetella pertussis and bordetella bronchiseptica are capable of obtaining iron from hemin and hemoglobin. genes encoding a putative bacterial heme iron acquisition system (bhu, for bordetella heme utilization) were identified in a b. pertussis genomic sequence database, and the corresponding dna was isolated from a virulent strain of b. pertussis. a b. pertussis bhur mutant, predicted to lack the heme outer membrane receptor, was generated by allelic exchange. in contrast to the wild-type stra ...200111418569
development of a genetic system for geobacter sulfurreducens.members of the genus geobacter are the dominant metal-reducing microorganisms in a variety of anaerobic subsurface environments and have been shown to be involved in the bioremediation of both organic and metal contaminants. to facilitate the study of the physiology of these organisms, a genetic system was developed for geobacter sulfurreducens. the antibiotic sensitivity of this organism was characterized, and optimal conditions for plating it at high efficiency were established. a protocol for ...200111425739
molecular characterization of chromosomal class c beta-lactamase and its regulatory gene in ochrobactrum anthropi.ochrobactrum anthropi, formerly known as cdc group vd, is an oxidase-producing, gram-negative, obligately aerobic, non-lactose-fermenting bacillus of low virulence that occasionally causes human infections. it is highly resistant to all beta-lactams except imipenem. a clinical isolate, slo74, and six reference strains were tested. mics of penicillins, aztreonam, and most cephalosporins tested, including cefotaxime and ceftazidime, were >128 microg/ml and of cefepime were 64 to >128 microg/ml. cl ...200111451692
in vitro activities of abt-773, a new ketolide, against aerobic and anaerobic pathogens isolated from antral sinus puncture specimens from patients with sinusitis.the comparative in vitro activities of abt-773 against 207 aerobic and 162 anaerobic antral sinus puncture isolates showed that erythromycin-resistant pneumococcal strains were susceptible to abt-773 (< or =0.125 microg/ml); the mic at which 90% of the isolates tested were inhibited for haemophilus influenzae and other haemophilus spp. was 4 microg/ml; and all moraxella spp. and beta-lactamase-producing prevotella species strains were inhibited by < or =0.125 microg/ml. among the anaerobes teste ...200111451698
activation of rho gtpases by cytotoxic necrotizing factor 1 induces macropinocytosis and scavenging activity in epithelial cells.macropinocytosis, a ruffling-driven process that allows the capture of large material, is an essential aspect of normal cell function. it can be either constitutive, as in professional phagocytes where it ends with the digestion of captured material, or induced, as in epithelial cells stimulated by growth factors. in this case, the internalized material recycles back to the cell surface. we herein show that activation of rho gtpases by a bacterial protein toxin, the escherichia coli cytotoxic ne ...200111452003
xenorhabdus nematophilus as a model for host-bacterium interactions: rpos is necessary for mutualism with nematodes.xenorhabdus nematophilus, a gram-negative bacterium, is a mutualist of steinernema carpocapsae nematodes and a pathogen of larval-stage insects. we use this organism as a model of host-microbe interactions to identify the functions bacteria require for mutualism, pathogenesis, or both. in many gram-negative bacteria, the transcription factor sigma(s) controls regulons that can mediate stress resistance, survival, or host interactions. therefore, we examined the role of sigma(s) in the ability of ...200111466270
role played by the response regulator ris in bordetella bronchiseptica resistance to macrophage killing.previous studies suggested that the persistence in eukaryotic cells of a bordetella bronchiseptica mutant carrying an insertion in the locus encoding the response regulator risas is impaired. this suggested that ris-dependent products are required for the intracellular survival of bacteria. in this study we demonstrate that ris-regulated products play a role in b. bronchiseptica resistance against both phagosomal acidification and reactive oxygen intermediates.200111470358
development of conventional and real-time pcr assays for detection of legionella dna in respiratory specimens.the development and validation of a pcr assay based on the use of new 16s ribosomal dna (rdna)-targeted primers to detect legionella dna in respiratory specimens are described. the assay was originally developed as conventional pcr followed by electrophoretic detection and was then adapted to lightcycler format with sybr green i detection and melting curve analysis. the 73 legionella pneumophila strains tested were amplified with both applications. in addition, 21 and 23 out of 27 other legionel ...200111474011
globin-coupled sensors: a class of heme-containing sensors in archaea and bacteria.the recently discovered prokaryotic signal transducer hemat, which has been described in both archaea and bacteria, mediates aerotactic responses. the n-terminal regions of hemat from the archaeon halobacterium salinarum (hemat-hs) and from the gram-positive bacterium bacillus subtilis (hemat-bs) contain a myoglobin-like motif, display characteristic heme-protein absorption spectra, and bind oxygen reversibly. recombinant hemat-hs and hemat-bs shorter than 195 and 176 residues, respectively, do ...200111481493
demonstration of polysaccharide capsule in campylobacter jejuni using electron microscopy.recently, we reported that campylobacter jejuni, an important gastrointestinal pathogen, has the genetic determinants to produce a capsular polysaccharide (karlyshev et al., mol. microbiol. 35:529-541, 2000). despite these data, the presence of a capsule in these bacteria has remained controversial. in this study we stain c. jejuni cells with the cationic dye alcian blue and demonstrate for the first time by electron microscopy that c. jejuni cells produce a polysaccharide capsule that is retain ...200111500474
escherichia coli cytotoxic necrotizing factor and pasteurella multocida toxin induce focal adhesion kinase autophosphorylation and src association.cytotoxic necrotizing factor 1 and pasteurella multocida toxin induced dose- and time-dependent increases in focal adhesion kinase (fak) tyr397 phosphorylation in swiss 3t3 cells. fak autophosphorylation was sensitive to inhibitors of p160/rock and coincided with the formation of stable complexes between fak and src family members.200111500476
experimental infection of conventional pigs with streptococcus suis serotype 2 by aerosolic exposure. 200111503376
identification of strains of alcaligenes and agrobacterium by a polyphasic approach.the number of stable discriminant biochemical characters is limited in the genera alcaligenes and agrobacterium, whose species are consequently difficult to distinguish from one another by conventional tests. moreover, genomic studies have recently drastically modified the nomenclature of these genera; for example, alcaligenes xylosoxidans was transferred to the genus achromobacter in 1998. twenty-five strains of achromobacter xylosoxidans, three strains of an agrobacterium sp., five strains of ...200111526136
serum immunoglobulin g antibody responses to bordetella pertussis lipooligosaccharide and b. parapertussis lipopolysaccharide in children with pertussis and parapertussis.serum immunoglobulin g (igg) antibodies against the lipooligosaccharide (los) of bordetella pertussis and the lipopolysaccharide (lps) of bordetella parapertussis were measured by enzyme-linked immunosorbent assay in paired sera from 40 children with pertussis and 14 with parapertussis. wide differences in the individual responses were noted. both anti-los and -lps igg levels increased significantly in the children with pertussis, as did anti-lps but not anti-los in those with parapertussis.200111527820
bordetella bronchiseptica fimbrial protein-enhanced immunogenicity of a mannheimia haemolytica leukotoxin fragment.leukotoxin produced by mannheimia (pasteurella) haemolytica is an important virulence factor in shipping fever pneumonia in feedlot cattle and is a critical protective antigen. in this study, the immune response to a chimeric protein generated by combining a gene fragment encoding neutralizing epitopes of m. haemolytica leukotoxin and a fimbrial protein gene (fim n) from bordetella bronchiseptica was evaluated. the recombinant gene was cloned in a bacterial expression vector under the control of ...200111535337
complete nucleotide sequence of a 43-kilobase genomic island associated with the multidrug resistance region of salmonella enterica serovar typhimurium dt104 and its identification in phage type dt120 and serovar agona.this study describes the characterization of the recently described salmonella genomic island 1 (sgi1) (d. a. boyd, g. a. peters, l.-k. ng, and m. r. mulvey, fems microbiol. lett. 189:285-291, 2000), which harbors the genes associated with the acssut phenotype in a canadian isolate of salmonella enterica serovar typhimurium dt104. a 43-kb region has been completely sequenced and found to contain 44 predicted open reading frames (orfs) which comprised approximately 87% of the total sequence. fift ...200111544236
role of adp-ribosyltransferase activity of pertussis toxin in toxin-adhesin redundancy with filamentous hemagglutinin during bordetella pertussis infection.pertussis toxin (pt) and filamentous hemagglutinin (fha) are two major virulence factors of bordetella pertussis. fha is the main adhesin, whereas pt is a toxin with an a-b structure, in which the a protomer expresses adp-ribosyltransferase activity and the b moiety is responsible for binding to the target cells. here, we show redundancy of fha and pt during infection. whereas pt-deficient and fha-deficient mutants colonized the mouse respiratory tract nearly as efficiently as did the isogenic p ...200111553541
identification of a new iron-regulated virulence gene, irea, in an extraintestinal pathogenic isolate of escherichia coli.our laboratory is studying an extraintestinal pathogenic isolate of escherichia coli (cp9) as a model pathogen. we have been using human urine, ascites, and blood ex vivo to identify genes with increased expression in these media relative to expression in luria-bertani (lb) broth. such genes may represent new or unrecognized virulence traits. in this study, we report the identification of a new gene, irea (iron-responsive element). this gene has an open reading frame of 2,049 nucleotides, and it ...200111553562
gonococcal genes encoding transferrin-binding proteins a and b are arranged in a bicistronic operon but are subject to differential expression.neisseria gonorrhoeae is capable of utilizing host iron-binding proteins, such as transferrin, lactoferrin, and hemoglobin, as the sole source of iron. the receptor involved in transferrin iron acquisition is composed of two distinct transferrin-binding proteins, tbpa and tbpb. the genes that encode these proteins are linked on the chromosome in the order tbpb-tbpa but are separated by an inverted repeat of unknown function. in this study, we sought to understand the transcriptional organization ...200111553578
phenotype evaluation of bordetella bronchiseptica cultures by urease activity and congo red affinity.the present study shows that congo red binding and urease activity assays are useful for selection of virulent (bvg+) bordetella bronchiseptica cultures.200111559402
genome sequence of an industrial microorganism streptomyces avermitilis: deducing the ability of producing secondary metabolites.streptomyces avermitilis is a soil bacterium that carries out not only a complex morphological differentiation but also the production of secondary metabolites, one of which, avermectin, is commercially important in human and veterinary medicine. the major interest in this genus streptomyces is the diversity of its production of secondary metabolites as an industrial microorganism. a major factor in its prominence as a producer of the variety of secondary metabolites is its possession of several ...200111572948
the esat-6 gene cluster of mycobacterium tuberculosis and other high g+c gram-positive bacteria.the genome of mycobacterium tuberculosis h37rv has five copies of a cluster of genes known as the esat-6 loci. these clusters contain members of the cfp-10 (lhp) and esat-6 (esat-6) gene families (encoding secreted t-cell antigens that lack detectable secretion signals) as well as genes encoding secreted, cell-wall-associated subtilisin-like serine proteases, putative abc transporters, atp-binding proteins and other membrane-associated proteins. these membrane-associated and energy-providing pro ...200111597336
candida albicans is phagocytosed, killed, and processed for antigen presentation by human dendritic cells.candida albicans is a component of the normal flora of the alimentary tract and also is found on the mucocutaneous membranes of the healthy host. candida is the leading cause of invasive fungal disease in premature infants, diabetics, and surgical patients, and of oropharyngeal disease in aids patients. as the induction of cell-mediated immunity to candida is of critical importance in host defense, we sought to determine whether human dendritic cells (dc) could phagocytose and degrade candida an ...200111598054
cytotoxic necrotizing factor from escherichia coli induces rhoa-dependent expression of the cyclooxygenase-2 gene.cytotoxic necrotizing factor 1 (cnf) is a toxin produced by some isolates of escherichia coli that cause extraintestinal infections. cnf can initiate signaling pathways that are mediated by the rho family of small gtpases through a covalent modification that results in constitutive activation. in addition to regulating the assembly of actin stress fibers and focal adhesion complexes, rhoa can also regulate gene expression at the level of transcription. here we demonstrate for the first time, by ...200111598057
heme utilization in bordetella avium is regulated by rhui, a heme-responsive extracytoplasmic function sigma factor.efficient utilization of heme as an iron (fe) source by bordetella avium requires bhur, an fe-regulated gene which encodes an outer membrane heme receptor. upstream of bhur is a 507-bp open reading frame, hereby designated rhui (for regulator of heme uptake), which codes for a 19-kda polypeptide. whereas the 19-kda polypeptide had homology to a subfamily of alternative sigma factors known as the extracytoplasmic function (ecf) sigma factors, it was hypothesized that rhui encoded a potential in-t ...200111598070
reciprocal protective immunity against bordetella pertussis and bordetella parapertussis in a murine model of respiratory infection.the protective immunity induced by infection with bordetella pertussis and with bordetella parapertussis was examined in a murine model of respiratory infection. convalescent mice that had been infected by aerosol with b. pertussis or with b. parapertussis exhibited a protective immune response against b. pertussis and also against b. parapertussis. anti-filamentous hemagglutinin (anti-fha) serum immunoglobulin g (igg) and anti-fha lung iga antibodies were detected in both mice infected with b. ...200111598073
a mems based amperometric detector for e. coli bacteria using self-assembled monolayers.we developed a system for amperometric detection of escherichia coli (e. coli) based on the integration of microelectromechanical systems (mems), self-assembled monolayers (sams), dna hybridization, and enzyme amplification. using mems technology, a detector array was fabricated which has multiple electrodes deposited on a si wafer and was fully reusable. using sams, a monolayer of the protein streptavidin was immobilized on the working electrode (au) surface to capture rrna from e. coli. three ...200111679252
[the current antimicrobial resistance situation in swiss veterinary medicine].antimicrobial susceptibility data (n = 1501) and bacterial isolates (n = 258) of important bacterial pathogens from animals were collected in collaboration with eight swiss laboratories from may 1999 to february 2000. using these data, the antimicrobial resistance situation could be assessed for the following bacterial species: escherichia coli, salmonella, haemophilus parasuis, actinobacillus pleuropneumoniae, pasteurella multocida, mannheimia haemolytica, bordetella bronchiseptica, campylobact ...200111680911
infected branchial cleft cyst due to bordetella bronchiseptica in an immunocompetent patient.a healthy 23-year-old man with fever and a tender mass in his right anterior neck was found to have a branchial cleft cyst infected with bordetella bronchiseptica. initial testing suggested a brucella species, but further laboratory testing identified the organism definitively. b. bronchiseptica infection in healthy adults is an unusual event.200111682564
pertussis toxin and lipopolysaccharide influence phagocytosis of bordetella pertussis by human monocytes.the potential of human monocytes to mediate the clearance of bordetella pertussis infection was examined. bacteria expressing green fluorescent protein were incubated with adherent peripheral blood monocytes, and phagocytosis was quantified by using fluorescence microscopy. monocytes internalized only a small percentage of the adherent bacteria. surface-associated bvg-regulated virulence factors, including adenylate cyclase toxin and filamentous hemagglutinin, did not affect attachment or phagoc ...200111705943
lysine and polyamines are substrates for transglutamination of rho by the bordetella dermonecrotic toxin.bordetella dermonecrotic toxin (dnt) catalyzes the transglutamination of glutamine-63/61 of rho gtpases, thereby constitutively activating rho proteins. here we identified second substrates for transglutamination of rhoa by dnt. the enzymatically active fragment of dnt (residues 1136 to 1451, deltadnt) induced the incorporation of l-[(14)c]lysine in rhoa in a concentration-dependent manner. also, rac and cdc42, but not ras, were transglutaminated with lysine by deltadnt. transglutamination of th ...200111705946
localization of functional domains of the mitogenic toxin of pasteurella multocida.the locations of the catalytic and receptor-binding domains of the pasteurella multocida toxin (pmt) were investigated. n- and c-terminal fragments of pmt were cloned and expressed as fusion proteins with affinity tags. purified fusion proteins were assessed in suitable assays for catalytic activity and cell-binding ability. a c-terminal fragment (amino acids 681 to 1285) was catalytically active. when microinjected into quiescent swiss 3t3 cells, it induced changes in cell morphology typical of ...200111705966
laribacter hongkongensis gen. nov., sp. nov., a novel gram-negative bacterium isolated from a cirrhotic patient with bacteremia and empyema.a bacterium was isolated from the blood and empyema of a cirrhotic patient. the cells were facultatively anaerobic, nonsporulating, gram-negative, seagull shaped or spiral rods. the bacterium grows on sheep blood agar as nonhemolytic, gray colonies 1 mm in diameter after 24 h of incubation at 37 degrees c in ambient air. growth also occurs on macconkey agar and at 25 and 42 degrees c but not at 4, 44, and 50 degrees c. the bacterium can grow in 1 or 2% but not 3, 4, or 5% nacl. no enhancement of ...200111724825
polymorphism of bordetella pertussis isolates circulating for the last 10 years in france, where a single effective whole-cell vaccine has been used for more than 30 years.we compared bordetella pertussis isolates collected in france over the last 10 years, the vaccine strains used for more than 30 years, and isolates collected before the introduction of generalized vaccination. the analysis included serotyping, pulsed-field gel electrophoresis of chromosomal dna after digestion with xbai and spei, and sequencing of the pt s1 gene, encoding the s1 subunit of pertussis toxin, and the prn gene, encoding the adhesin pertactin. we found that the incidence of infection ...200111724851
case of catheter sepsis with ralstonia gilardii in a child with acute lymphoblastic leukemia.acute lymphoblastic leukemia was diagnosed in a 7-year-old girl. two months after insertion of a central venous catheter, she developed fever and complained of headache and abdominal pain. physical examination revealed no focus of infection. a gram-negative nonfermenting bacillus was recurrently cultured from blood. extensive biochemical testing and 16s ribosomal dna sequencing led to the identification of ralstonia gilardii.200111724891
construction of mini-tn5cyaa' and its utilization for the identification of genes encoding surface-exposed and secreted proteins in bordetella bronchiseptica.a mini-tn5 transposon derivative, mini-tn5cyaa', has been constructed. it contains a promoter-less and ribosome binding site-deficient reporter gene, encoding the catalytic domain of bordetella pertussis adenylate cyclase toxin (cyaa'). we used this system to mutagenize b. bronchiseptica and we developed a screen for identification of mutants containing cyaa' translational fusions. this system was used to identify b. bronchiseptica genes that encode surface-exposed and secreted proteins.200111728725
betawrap: successful prediction of parallel beta -helices from primary sequence reveals an association with many microbial pathogens.the amino acid sequence rules that specify beta-sheet structure in proteins remain obscure. a subclass of beta-sheet proteins, parallel beta-helices, represent a processive folding of the chain into an elongated topologically simpler fold than globular beta-sheets. in this paper, we present a computational approach that predicts the right-handed parallel beta-helix supersecondary structural motif in primary amino acid sequences by using beta-strand interactions learned from non-beta-helix struct ...200111752429
multiplex lightcycler pcr assay for detection and differentiation of bordetella pertussis and bordetella parapertussis in nasopharyngeal specimens.a rapid real-time multiplex pcr assay for detecting and differentiating bordetella pertussis and bordetella parapertussis in nasopharyngeal swabs was developed. this assay (lc-pcr-is) targets the insertion sequences is481 and is1001 of b. pertussis and b. parapertussis, respectively, and is performed using the lightcycler (roche molecular biochemicals, indianapolis, ind.). the analytical sensitivity is less than one organism per reaction. results for bordetella culture and/or direct fluorescent ...200211773099
role of the dermonecrotic toxin of bordetella bronchiseptica in the pathogenesis of respiratory disease in swine.bordetella bronchiseptica is one of the etiologic agents causing atrophic rhinitis and pneumonia in swine. it produces several purported virulence factors, including the dermonecrotic toxin (dnt), which has been implicated in the turbinate atrophy seen in cases of atrophic rhinitis. the purpose of these experiments was to clarify the role of this toxin in respiratory disease by comparing the pathogenicity in swine of two isogenic dnt mutants to their virulent dnt(+) parent strains. two separate ...200211796573
adherence of burkholderia pseudomallei cells to cultured human epithelial cell lines is regulated by growth temperature.we have investigated the adherence of burkholderia pseudomallei, cultured under a number of different conditions, to six human epithelial cell lines. while several complex medium compositions had relatively little effect on adherence, growth at 30 degrees c was found to significantly increase adherence to all cell lines relative to that of cultures grown at 37 degrees c (p < 0.001).200211796634
transcriptional and proteomic analysis of a ferric uptake regulator (fur) mutant of shewanella oneidensis: possible involvement of fur in energy metabolism, transcriptional regulation, and oxidative stress.the iron-directed, coordinate regulation of genes depends on the fur (ferric uptake regulator) gene product, which acts as an iron-responsive, transcriptional repressor protein. to investigate the biological function of a fur homolog in the dissimilatory metal-reducing bacterium shewanella oneidensis mr-1, a fur knockout strain (fur1) was generated by suicide plasmid integration into this gene and characterized using phenotype assays, dna microarrays containing 691 arrayed genes, and two-dimensi ...200211823232
contribution of fibronectin-binding protein to pathogenesis of streptococcus suis serotype 2.in the present study we investigated the role of the fibronectin (fn)- and fibrinogen (fgn)-binding protein (fbps) in the pathogenesis of streptococcus suis serotype 2 in piglets. the complete gene encoding fbps from s. suis serotype 2 was cloned in escherichia coli and sequenced. the occurrence of the gene in various serotypes was analyzed by hybridization studies. the fbps protein was expressed in e. coli and purified, and binding to human fn and fgn was demonstrated. the induction of antibodi ...200211854216
genetic differentiation between sympatric populations of bacillus cereus and bacillus thuringiensis.little is known about genetic exchanges in natural populations of bacteria of the spore-forming bacillus cereus group, because no population genetics studies have been performed with local sympatric populations. we isolated strains of bacillus thuringiensis and b. cereus from small samples of soil collected at the same time from two separate geographical sites, one within the forest and the other at the edge of the forest. a total of 100 b. cereus and 98 b. thuringiensis strains were isolated an ...200211872495
mutational analysis of the tonb1 energy coupler of pseudomonas aeruginosa.siderophore-mediated iron transport in pseudomonas aeruginosa is dependent upon the cytoplasmic membrane-associated tonb1 energy coupling protein for activity. to assess the functional significance of the various regions of this molecule and to identify functionally important residues, the tonb1 gene was subjected to site-directed mutagenesis, and the influence on iron acquisition was determined. the novel n-terminal extension of tonb1, which is absent in all other examples of tonb, was required ...200211872700
bordetella interspecies allelic variation in alcr inducer requirements: identification of a critical determinant of alcr inducer responsiveness and construction of an alcr(con) mutant allele.previous studies established the critical roles of alcr and alcaligin inducer in positive regulation of alcaligin siderophore biosynthesis and transport genes in bordetella pertussis and bordetella bronchiseptica. transcriptional analyses using plasmid-borne alcr genes of b. pertussis ut25 and b. bronchiseptica b013n to complement the alcr defect of b. bronchiseptica strain brm13 (delta alcr1 alca::mini-tn5 lacz1) revealed interspecies differences in alcr inducer requirements for activation of a ...200211872703
transfer rna-dependent amino acid biosynthesis: an essential route to asparagine formation.biochemical experiments and genomic sequence analysis showed that deinococcus radiodurans and thermus thermophilus do not possess asparagine synthetase (encoded by asna or asnb), the enzyme forming asparagine from aspartate. instead these organisms derive asparagine from asparaginyl-trna, which is made from aspartate in the trna-dependent transamidation pathway [becker, h. d. & kern, d. (1998) proc. natl. acad. sci. usa 95, 12832-12837; and curnow, a. w., tumbula, d. l., pelaschier, j. t., min, ...200211880622
relaxed acyl chain specificity of bordetella udp-n-acetylglucosamine acyltransferases.lipid a (endotoxin) is a major structural component of gram-negative outer membranes. it also serves as the hydrophobic anchor of lipopolysaccharide and is a potent activator of the innate immune response. lipid a molecules from the genus bordetella are reported to exhibit unusual structural asymmetry with respect to the acyl chains at the 3- and 3'-positions. these acyl chains are attached by udp-n-acetylglucosamine acyltransferase (lpxa). to determine the origin of the acyl variability, the si ...200211889134
in vitro and in vivo characterization of a bordetella bronchiseptica mutant strain with a deep rough lipopolysaccharide structure.bordetella bronchiseptica is closely related to bordetella pertussis, which produces respiratory disease primarily in mammals other than humans. however, its importance as a human pathogen is being increasingly recognized. although a large amount of research on bordetella has been generated regarding protein virulence factors, the participation of the surface lipopolysaccharide (lps) during b. bronchiseptica infection is less understood. to get a better insight into this matter, we constructed a ...200211895940
helicobacter pylori uses motility for initial colonization and to attain robust infection.helicobacter pylori has been shown to require flagella for infection of the stomach. to analyze whether flagella themselves or motility is needed by these pathogens, we constructed flagellated nonmotile mutants. this was accomplished by using both an insertion mutant and an in-frame deletion of the motb gene. in vitro, these mutants retain flagella (fla(+)) but are nonmotile (mot(-)). by using fvb/n mice, we found that these mutants had reduced ability to infect mice in comparison to that of the ...200211895962
evaluation of vaccines for atrophic rhinitis--a comparison of three challenge models.we compared three challenge models for the assessment of atrophic rhinitis (ar) vaccines: combined infection with bordetella bronchiseptica (bb) and pasteurella multocida (pm); application of acetic acid (aa) to the nasal mucosa followed by pm infection; and bb infection alone. two vaccines were tested using standardized criteria, notably nasal lesion scores. the vaccines provided different levels of protection in the bb and the aa/pm challenges, but were similar in the combined (bb/pm) challeng ...200211906767
ribosomal dna-directed pcr for identification of achromobacter (alcaligenes) xylosoxidans recovered from sputum samples from cystic fibrosis patients.the opportunistic human pathogen achromobacter (alcaligenes) xylosoxidans has been recovered with increasing frequency from respiratory tract culture of persons with cystic fibrosis (cf). however, confusion of this species with other closely related respiratory pathogens has limited studies to better elucidate its epidemiology, natural history, and pathogenic role in cf. misidentification of a. xylosoxidans as burkholderia cepacia complex is especially problematic and presents a challenge to eff ...200211923333
dsba and dsbc are required for secretion of pertussis toxin by bordetella pertussis.the dsb family of enzymes catalyzes disulfide bond formation in the gram-negative periplasm, which is required for folding and assembly of many secreted proteins. pertussis toxin is arguably the most complex toxin known: it is assembled from six subunits encoded by five genes (for subunits s1 to s5), with 11 intramolecular disulfide bonds. to examine the role of the dsb enzymes in assembly and secretion of pertussis toxin, we identified and mutated the bordetella pertussis dsba, dsbb, and dsbc h ...200211953363
comparative and genetic analyses of the putative vibrio cholerae lipopolysaccharide core oligosaccharide biosynthesis (wav) gene cluster.we identified five different putative wav gene cluster types, which are responsible for the synthesis of the core oligosaccharide (os) region of vibrio cholerae lipopolysaccharide. preliminary evidence that the genes encoded by this cluster are involved in core os biosynthesis came from analysis of the recently released o1 el tor v. cholerae genome sequence and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of o1 el tor mutant strains defective in three genes (waaf, waal, and ...200211953379
cloning of escherichia coli lacz and lacy genes and their expression in gluconobacter oxydans and acetobacter liquefaciens.an efficient transformation protocol for gluconobacter oxydans and acetobacter liquefaciens strains was developed by preparation of electrocompetent cells grown on yeast extract-ethanol medium. plasmid pbbr122 was used as broad-host-range vector to clone the escherichia coli laczy genes in g. oxydans and a. liquefaciens. although both lac genes were functionally expressed in both acetic acid bacteria, only a few transformants were able to grow on lactose. however, this ability strictly depended ...200211976147
evaluation of non-cyanobacterial genome sequences for occurrence of genes encoding proteins homologous to cyanophycin synthetase and cloning of an active cyanophycin synthetase from acinetobacter sp. strain dsm 587.all publicly accessible microbial genome databases were searched for the occurrence of genes encoding proteins homologous to the cyanophycin synthetase (cpha) of synechocystis sp. strain pcc 6803 in order to reveal the capability of microorganisms not belonging to the cyanobacteria to synthesize cyanophycin. among 65 genome sequences, genes homologous to cpha were found in acinetobacter sp. strain adp1 (encoding a protein homologous to cpha with 40% amino acid identity), bordetella bronchiseptic ...200211976746
real-time lightcycler pcr for detection and discrimination of bordetella pertussis and bordetella parapertussis.real-time pcr assays based on the lightcycler technology were developed for individual (simplex pcr) and simultaneous (duplex pcr) detection and discrimination of bordetella pertussis and bordetella parapertussis in clinical samples. the assays were evaluated with 113 specimens from patients with and without symptoms of pertussis. results were compared to those from conventional culture and taqman real-time pcr. the analytical sensitivity ranged from 0.1 to 10 cfu for b. pertussis and b. paraper ...200211980949
comparative evaluation of the bd phoenix and vitek 2 automated instruments for identification of isolates of the burkholderia cepacia complex.we evaluated two new automated identification systems, the bd phoenix (becton dickinson) and the vitek 2 (biomérieux), for identification of isolates of the burkholderia cepacia complex (bcc). the test sample included 42 isolates of the highly virulent and epidemic genomovar iii, 45 isolates of b. multivorans, and 47 isolates of other members of the bcc. rates of correct identification by the bd phoenix and vitek 2 were similar when all bcc isolates were considered (50 and 53%, respectively) but ...200211980954
base-specific fragmentation of amplified 16s rrna genes analyzed by mass spectrometry: a tool for rapid bacterial identification.a rapid approach to the 16s rrna gene (16s rdna)-based bacterial identification has been developed that combines uracil-dna-glycosylase (udg)-mediated base-specific fragmentation of pcr products with matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (maldi-tof ms). 16s rdna signature sequences were pcr-amplified from both cultured and as-yet-uncultured bacteria in the presence of dutp instead of dttp. these pcr products then were immobilized onto a streptavidin-coated ...200211983869
studies of the efficacy of a novel intranasal vaccine against feline bordetellosis.a novel intranasal vaccine against disease caused by bordetella bronchiseptica in cats was tested in a series of three experiments. in the first experiment a vaccinated group and an unvaccinated control group of kittens were challenged by the aerosol route with virulent b bronchiseptica three weeks after they had been vaccinated. the control kittens developed upper respiratory tract signs typical of feline b bronchiseptica infection, including rhinitis, a serous ocular and nasal discharge, fever ...200211993973
use of a rationally attenuated bordetella bronchiseptica as a live mucosal vaccine and vector for heterologous antigens.inactivation of the aroa gene of bordetella bronchiseptica severely impaired its ability to colonise the respiratory tract of mice. the b. bronchiseptica aroa mutant was investigated as a live vaccine and vector for heterologous antigens. the b. bronchiseptica aroa mutant expressing the non-toxic fragment c (frgc) of tetanus toxin (strain gvb120) was used to immunise mice intranasally. immunised mice produced a strong serum and mucosal antibody response to b. bronchiseptica and serum anti-frgc a ...200212009288
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