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[long-chain fatty acids of pasteurella multocida nad pasteurella haemolytica].the relative contents of long-chain fatty acids in p. multocida and p. haemolytica were investigated. a dependence on the composition of the broth was established. accordingly, comparative quantitative studies on fatty acid contents have to be conducted using bacteria grown with the same lot of broth medium. as for p. multocida, there were significant differences between the serovars (c14 in tdhm and c16, delta 2c18 in bpl). these differences are, however, not significant to replace serotyping. ...199710084940
[investigation of outer membrane proteins of pasteurella. 2: iron-regulated outer membrane proteins of pasteurella multocida and pasteurella haemolytica].pasteurella multocida and pasteurella haemolytica produce specific proteins in the outer membrane under iron-depleted conditions. pasteurella multocida serovar a expresses these proteins of molecular masses of 76 and 96 kda as determined by electrophoresis. the analogous serovar d produces a further iron-regulated protein of 85 kda. the pasteurella haemolytica strains of serovar a1, a6 and t contain iron-regulated outer membrane proteins of molecular masses of 71, 77 and 100 kda. these proteins ...199710084945
expression of tissue factor in experimental bovine pneumonic pasteurellosis and endotoxemia.tissue factor (tf), a cell surface-associated cofactor and activator of coagulation factor vii, has been implicated in the local and systemic activation of coagulation associated with sepsis. this study describes the pattern of tf expression in experimental bovine pneumonic pasteurellosis and endotoxemia. immunohistochemical techniques were used to localize tf antigen in tissue sections. tissue factor expression was not observed in tissues from control animals. in response to pasteurella haemoly ...199712658585
purification and partial characterization of the ompa family of proteins of pasteurella haemolytica.this study was conducted to partially characterize and identify the purity of two major outer membrane proteins (omps) (with molecular weights of 32,000 and 35,000 [32k and 35k, respectively]) of pasteurella haemolytica. the 35k and 32k major omps, designated pasteurella outer membrane proteins a and b (poma and pomb, respectively), were extracted from p. haemolytica by solubilization in n-octyl polyoxyl ethylene. the p. haemolytica strain used was a mutant serotype a1 from which the genes expre ...19978975914
role of tissue factor in intra-alveolar fibrin deposition and coagulopathy associated with pneumonic pasteurellosis in cattle.to determine the role of tissue factor (tf) in the coagulation events leading to intra-alveolar fibrin deposition and intravascular thrombosis associated with pneumonic pasteurellosis in cattle.19978989492
structure-function studies of the adenylate cyclase toxin of bordetella pertussis and the leukotoxin of pasteurella haemolytica by heterologous c protein activation and construction of hybrid proteins.the adenylate cyclase toxin (cyaa) from bordetella pertussis and the leukotoxin (lkta) from pasteurella haemolytica are members of the rtx (stands for repeats in toxin) family of cytolytic toxins. they have pore-forming activity and share significant amino acid homology but show marked differences in biological activity. cyaa is an invasive adenylate cyclase and a weak hemolysin which is active on a wide range of mammalian cells. lkta is a cytolytic protein with a high target cell specificity an ...19979006045
isolation and characterization of the integration host factor genes of pasteurella haemolytica.using a bacteriophage lambda complementation system in escherichia coli, we cloned genes encoding subunits of the heterodimeric dna binding/bending protein, integration host factor, from the bovine pathogen, pasteurella haemolytica. complementation of ihfa and ihfb mutations in e. coli demonstrated that the p. haemolytica gene products form functional heterologous heterodimers. the ihfa and ihfb genes encode polypeptides predicted to be 99 and 93 amino acids long, respectively, and are very simi ...19979011038
development and characterisation of a model of bovine inflammation.two dialysis sacs each containing 50 ml dextran sulphate solution were implanted into the peritoneal cavities of five three month-old calves. one sac was inoculated with pasteurella haemolytica or streptococcus uberis and the second sac served as an uninoculated control. samples of sac fluid removed after 0, four, six, eight, 15, 24, 36 and 48 hours and then at 24 hour intervals after inoculation revealed bacterial growth up to 9.0 log10 cfu ml-1 by two to three days after inoculation. concentra ...19979160425
divergent activity and function of superoxide dismutases in pasteurella haemolytica serotypes a1 and a2 and pasteurella trehalosi serotype t10.representative strains of pasteurella haemolytica serotypes a1 and a2 and pasteurella trehalosi serotype t10 were examined for the presence of superoxide dismutase. visualisation of superoxide dismutase enzyme activity on polyacrylamide gels, and specific inhibition with potassium cyanide verified a copper/zinc (cu/zn) superoxide dismutase only in serotype a2 whereas serotypes a1 and t10 showed other superoxide dismutase activity. using a simple freeze-thaw method the cellular location of supero ...19979170262
detection of rtx toxin genes in gram-negative bacteria with a set of specific probes.the family of rtx (rtx representing repeats in the structural toxin) toxins is composed of several protein toxins with a characteristic nonapeptide glycine-rich repeat motif. most of its members were shown to have cytolytic activity. by comparing the genetic relationships of the rtx toxin genes we established a set of 10 gene probes to be used for screening as-yet-unknown rtx toxin genes in bacterial species. the probes include parts of apxia, apxiia, and apxiiia from actinobacillus pleuropneumo ...19979172345
udder orf infection and its role in ovine clinical mastitis caused by pasteurella haemolytica.during an experimental study of ovine subclinical mastitis caused by coagulase-negative staphylococci, an outbreak of contagious ecthyma occurred among ewes unvaccinated against parapox virus. the same group of ewes developed a high rate (43.7%) of clinical mastitis caused by pasteurella haemolytica. the rate of clinical mastitis among ewes vaccinated against parapox virus was very low (3.7%) suggesting that the presence of orf in the unvaccinated ewes was contributing to the high rate of clinic ...19979176868
pulmonary venous thrombosis in caprine pasteurella pneumonia.a 3-year-old angora goat that developed acute fibrinous pleuropneumonia associated with pasteurella haemolytica infection had thrombotic occlusion of a large pulmonary vein. thrombosis of pulmonary capillaries occurs in pneumonic pasteurellosis, but large vessels are not commonly affected. this unusual lesion may reflect the procoagulant effect of pasteurella endotoxin on vascular endothelium. an incidental observation was the presence of myocardial-type muscle fibres in the tunica media of the ...19979179755
two genes encoding serine protease homologues in serratia marcescens and characterization of their products in escherichia coli.a serine protease (ssp) of serratia marcescens is one of the extracellular enzymes secreted from this gram-negative bacterium. ssp is produced as a large precursor and converted to a mature protein by cleavages removing an nh2-terminal signal sequence and a cooh-terminal pro-region. this cooh-terminal pro-region is integrated into the outer membrane and has a functional role for the export of the mature protein across the outer membrane. southern hybridization analysis with a dna fragment encodi ...19979192732
efficacy of the combination sodium ceftiofur-flumethasone in the treatment of experimental pasteurella haemolytica bronchopneumonia in calves.severe acute bronchopneumonia was induced in 18 conventional friesian-holstein calves by inoculating them intratracheally with pasteurella haemolytica type a1. six of the calves received no treatment and served as controls. six of the calves were treated with sodium ceftiofur and six were treated with sodium ceftiofur and flumethasone. the mortality rate in the group of calves treated with sodium ceftiofur and flumethasone was significantly lower and their clinical and haematological parameters ...19979197206
generation of targeted nonpolar gene insertions and operon fusions in pasteurella haemolytica and creation of a strain that produces and secretes inactive leukotoxin.an efficient method for targeted gene inactivation and generation of chromosomal gene fusions in pasteurella haemolytica has been devised and used to create an lktc::cat operon fusion by allelic exchange at the leukotoxin gene cluster (lktcabd). a copy of the lktc gene was insertionally inactivated by using a nonpolar, promoterless cat cassette and then delivered into p. haemolytica on a shuttle vector. plasmid incompatibility was used to detect clones where double recombination events had occur ...19979199425
growth of pasteurella haemolytica and production of its leukotoxin in semi-defined media.to develop semi-defined media that support growth of the bovine pathogen, pasteurella haemolytica, and use them to examine production of leukotoxin and an arginine-binding protein by this organism.19979215452
nitric oxide production following in vitro stimulation of ovine pulmonary alveolar macrophages.production of inducible nitric oxide (no) as measured by nitrite in supernatant from ovine pulmonary alveolar macrophage (pam) cultures was assessed following stimulation of pam with live cells and supernatants from corynebacterium pseudotuberculosis and pasteurella haemolytica cultures; purified bacterial lipopolysaccharide derived from both escherichia coli and pasteurella haemolytica alone and in combination with interferon-gamma or lymphocyte conditioned medium; or ovine lentivirus. pam cult ...19979223233
epithelial antibiotic induced in states of disease.epithelial defensins provide an active defense against the external microbial environment. we investigated the distribution and expression of this class of antimicrobial peptides in normal cattle and in animals in varying states of disease. beta-defensin mrna was found to be widely expressed in numerous exposed epithelia but was found at higher levels in tissues that are constantly exposed to and colonized by microorganisms. we observed induction in ileal mucosa during chronic infection with myc ...19979238038
treatment of experimentally induced pneumonic pasteurellosis of young calves with tilmicosin.twenty four (24) healthy male holstein calves (< 70 kg) were each experimentally infected by intrabronchial inoculation of 4.0 x 10(9) viable cells of pasteurella haemolytica-ai (b122) at time = 0 h. at 1 h following inoculation animals received either: 1) sham treatment with sterile 0.85% saline sc (n = 12); or 2) a single injection of 10 mg tilmicosin per kg body weight (n = 12). calves that were non-infected and tilmicosin-treated were also included for determining tilmicosin concentrations i ...19979242998
effect of simulated stress on susceptibility of bighorn sheep neutrophils to pasteurella haemolytica leukotoxin.we examined the effects of simulated stress on susceptibility of rocky mountain bighorn sheep (ovis canadensis canadensis) neutrophils to pasteurella haemolytica leukotoxin in a blocked, crossover experiment. ten captive-raised bighorn sheep were sampled 10 hr after separate administrations of long-acting adrenocorticotrophic hormone (acth) gel and normal saline (control). we then compared in vitro leukotoxin-dependent neutrophil death rates after exposure to culture supernatants from four uniqu ...19979249702
effects of trypanosoma evansi on the output of cells from a lymph node draining the site of pasteurella haemolytica vaccine administration.the prefemoral efferent lymphatics of sheep infected with trypanosoma evansi and inoculated with p. haemolytica vaccine and of those given only the vaccine, were surgically cannulated to study the effects of the infection on the total cellular output and output of blast cells from the node in response to the vaccine. t. evansi delayed and depressed the increases in total cell and lymphoblast outputs. in uninfected sheep, the total cellular output increased and peaked at more than twice the preva ...19979263845
bacterial identity and characteristics in healthy and unhealthy respiratory tracts of sheep and calves.the aim of this study was to compare different bacteriological aspects of the respiratory systems of healthy (h) versus unhealthy (uh) animals with respiratory signs. the prevalence of different bacterial species was determined in the upper and lower respiratory tract of h and uh najdi sheep, somali sheep and holstein calves. the characteristics of pasteurella spp. isolates, and the biotype of pasteurella haemolytica were identified in h and uh animals, eighteen out of 28 (64.3%) of the identifi ...19979266661
aspects of the pharmacokinetics of doxycycline given to healthy and pneumonic east african dwarf goats by intramuscular injection.the effect of experimentally induced pasteurella haemolytica pneumonia on the pharmacokinetics of doxycycline (doxycen retard) administered intramuscularly was studied in seven east african dwarf goats. the study was conducted in two consecutive phases, separated by a washout period of four weeks. the experimental infection, induced by intratracheal administration of 5 ml of 10(7) to 10(9) cfu/ml of pasteurella haemolytica, produced a temperature rise, depression and laboured breathing within 6- ...19979266665
computer-based analyses of the protein constituents of transport systems catalysing export of complex carbohydrates in bacteria.bacteria synthesize and secrete an array of complex carbohydrates including exopolysaccharides (epss), capsular polysaccharides (cpss), lipopolysaccharides (lpss), lipo-oligosaccharides (loss) and teichoic acids (tcas). we have analysed the families of homologous proteins that appear to mediate excretion of complex carbohydrates into or across the bacterial cell envelope. two principal families of cytoplasmic-membrane transport systems appear to drive polysaccharide export: polysaccharide-specif ...19979274022
evolutionary genetics of pasteurella haemolytica isolates recovered from cattle and sheep.genetic diversity and relationships among 194 pasteurella haemolytica isolates, which were recovered predominantly from cattle (39%) and sheep (58%) suffering from pneumonic pasteurellosis in the united kingdom, germany, and the united states, were estimated by examination of allelic variation at 18 enzyme-encoding loci detected by multilocus enzyme electrophoresis. the isolates formed two major divisions. one included 178 pasteurella haemolytica sensu stricto strains representing serotypes a1, ...19979284123
binding of pasteurella haemolytica leukotoxin to bovine leukocytes.pasteurella haemolytica is the principal bacterial pathogen in the bovine respiratory disease complex. this organism produces an exotoxin (referred to as leukotoxin) during logarithmic-phase growth that is a potent leukocyte-modulating agent. at low concentrations, it activates neutrophils and mononuclear phagocytes to release inflammatory mediators, while at the same time making these cells destined to undergo apoptotic cell death. at higher concentrations, the toxin causes rapid swelling and l ...19979284143
a putative leucine zipper activator of pasteurella haemolytica leukotoxin transcription and the potential for modulation of its synthesis by slipped-strand mispairing.a pasteurella haemolytica cosmid clone that activates leukotoxin transcription in escherichia coli has been isolated. the activator locus, alxa, is part of a continuous open reading frame that includes the type i hsdm methylase gene. alxa and hsdm peptides are processed from a precursor, and translation of the polyprotein can be modulated by slipped-strand mispairing across a pentanucleotide repeat, acagc, within the 5' end of alxa-hsdm. extracts containing alxa can bind to a leukotoxin promoter ...19979284183
efficacy of doxycycline in a goat model of pasteurella pneumonia.the clinical efficacy of doxycycline (doxycen, cenavisa, spain), a long-acting preparation, was evaluated for treatment of pasteurella haemolytica infection in 6 goats. one goat was not infected and served as a control. the disease was induced by intratracheal inoculation of 10(7) to 10(9) cfu of p. haemolytica. confirmation of respiratory disease was based on evidence of appropriate clinical signs. before and after initiation of doxycycline treatment on day 10, each goat was examined daily. thr ...19979291074
serum antibody responses of cattle vaccinated with partially purified native pasteurella haemolytica leukotoxin.the objective of these experiments was to study the serum antibody responses of cattle to partially purified, native pasteurella haemolytica a1 leukotoxin (lkt) formulated with a commercial aluminum hydroxide-dda-bromide adjuvant. in two experiments, calves received two intramuscular injections 21 days apart and sera were obtained periodically. serum antibody responses to p. haemolytica outer membrane proteins (omps), formalinized p. haemolytica, and lkt were determined. in experiment a, holstei ...19979302755
refolding of recombinant pasteurella haemolytica a1 glycoprotease expressed in an escherichia coli thioredoxin gene fusion system.pasteurella haemolytica a1 secretes an o-sialoglycoprotein endopeptidase (ec. 3.4.24.57) (glycoprotease: gcp) which is specific for o-linked sialoglycoproteins. when the cloned gene is expressed in escherichia coli, the recombinant glycoprotease (rgcp) is secreted to the periplasm where it is present as a disulfide-linked aggregate which lacks enzymatic activity. in vitro refolding and activation of rgcp by mammalian protein disulfide isomerase (pdi) or by the e. coli chaperones (dnak, dnaj and ...19979314606
nasal carriage of pasteurella haemolytica serotypes by sheep and goats in jordan. 19979316235
isolation of pasteurella haemolytica from grass, drinking water, and straw bedding used by sheep.pasteurella haemolytica was isolated from three of 18 grass samples and four of 18 water samples collected from two grazing fields occupied by sheep. this microorganism was also isolated from three of nine straw bedding samples collected from a pen housing ewes affected by mastitis caused by p. haemolytica. the same ewes developed scabbed papilloma-like lesions on the teat and udder skin. these lesions were colonized by p. haemolytica of various serotypes. colder, wetter weather seems to prolong ...19979321460
influence of immunization on the pulmonary inflammatory response of rabbits induced by pasteurella haemolytica a1 lipopolysaccharide.immune complex formation has long been thought to play a role in the pathogenesis of pasteurella haemolytica pneumonia. this study in laboratory rabbits was designed to investigate immune-mediated damage in respiratory tissue caused by lipopolysaccharide (lps). severe lesions were induced by the intratracheal (it) injection of p. haemolytica a1 lps (50 micrograms) into rabbits previously immunized with p. haemolytica killed whole cells emulsified with freund's incomplete adjuvant (fia); these le ...19979352438
increase of glycocalyx and altered lectin agglutination profiles of pasteurella haemolytica a1 after incubation in bovine subcutaneous tissue chambers in vivo or in ruminant serum in vitro.pasteurella haemolytica serotype a1 (bovine strain ok) was incubated for 2 and 6 h in bovine subcutaneous tissue chambers in vivo, and ovine strain 82-25 and bovine strain l011 were incubated in vitro for 2 h in heat-inactivated ovine or bovine serum from which gamma globulin had been depleted by protein g affinity chromatography to assess changes in morphology and lectin agglutination profiles (strains 82-25 and l101 only). cells, removed from chambers after 2 h, were covered with an extensive, ...19979038303
serotyping and enzyme characterization of pasteurella haemolytica and pasteurella multocida isolates recovered from pneumonic lungs of stressed feeder calves.ninety-one isolates of pasteurella multocida (pm)and 124 of pasteurella haemolytica (ph) were recovered from the lungs of calves that died of bovine respiratory tract disease (brtd). nine pm enzyme profiles (a through i) and 9 ph enzyme profiles (j through r) were determined for the pasteurella isolates. the pm isolates were relatively evenly divided among the enzyme profiles, with one exception, profile i. the ph isolates were not evenly distributed among the profiles. fifty of the 91 pm isolat ...19979058546
characterization of a pasteurella multocida plasmid and its use to express recombinant proteins in p. multocida.the complete nucleotide sequence of a naturally occurring 5.36-kb streptomycin and sulphonamide resistance plasmid, designated pig1, isolated from type d pasteurella multocida was determined. a 1.6-kb noncoding region and a 1.4-kb region encoding three putative proteins were shown by sequence homologies and functional characterizations to be involved in the replication and mobilization of pig1, respectively. the remaining sequence carried an unusual arrangement of streptomycin- and sulphonamide- ...19979073583
cloning and characterization of the exbb-exbd-tonb locus of pasteurella haemolytica a1.a recombinant plasmid (pmg1) carrying pasteurella haemolytica a1 dna which complements a tonb mutation of escherichia coli has been isolated. e. coli tonb mete which carries pmg1 exhibits growth kinetics in the presence of vitamin b12 similar to that of the wild-type host. in addition, the complemented e. coli is susceptible to killing by bacteriophage phi 80 and colicin b. analysis of the nucleotide sequence in the complementing dna showed that it codes for three genes in the order of exbb-exbd ...19979074497
plasmids for heterologous expression in pasteurella haemolytica.new cloning and expression vectors that replicate both in pasteurella haemolytica and in escherichia coli were constructed based on a native sulfonamide (sur) and streptomycin (smr) resistant plasmid of p. haemolytica called pyfc1. each shuttle vector includes an mcs and a selectable antibiotic resistance marker that is expressed in both organisms. plasmid pnf2176 carries the p. haemolytica rob-1 beta-lactamase gene (blap, apr) and pnf2214 carries the tn903 aph3 kanamycin resistance (kmr) elemen ...19979074498
effects of copper deficiency and copper deficiency coupled with high dietary iron or molybdenum on phagocytic cell function and response of calves to a respiratory disease challenge.a study was conducted to determine the effects of supplementing a diet marginally deficient in copper (cu) with iron (fe), molybdenum (mo), or cu on phagocytic cell function and disease resistance of calves. thirty-one calves were born to heifers fed a corn silage-based diet containing 4.5 mg of cu/kg. treatments consisted of 1) control (con; no supplemental cu, fe, or mo), 2) 600 mg of fe added/kg (fe), 3) 5 mg of mo added/kg (mo), or 4) 10 mg of cu added/kg of dm (cu). activity of superoxide d ...19979110227
characterisation of the leukotoxin produced by different strains of pasteurella haemolytica.pasteurella haemolytica isolates from cattle and sheep, including representatives of different serotypes and untypable strains, were examined for leukotoxin (lkt) production at the end of the log phase of growth in brain heart infusion broth. there were marked differences in leukotoxic activity in culture supernate samples, as measured by chemiluminescence-inhibition assays with bovine and ovine neutrophils, even between strains of the same serotype. there was also some variation in the amount a ...19979128191
relationships among strains classified with the ruminant pasteurella haemolytica-complex using quantitative evaluation of phenotypic data.the phenotypic relationships among 246 trehalose-negative strains classified under the [pasteurella] haemolytica-complex in ruminants were investigated by clustering and multidimensional ordinations based upon 79 phenotypic characters. a quantitative evaluation of phenotypic data using a 5-level scoring system is presented permitting a comprehensive utilization of the recorded phenotypic variation among the strains in the analyses. clustering and ordination analyses display complementary aspects ...19979144907
association of pasteurella haemolytica, pasteurella multocida and haemophilus somnus with pneumonia in calves.pathological and bacteriological observations were made on 100 (0.98%) pneumonic lungs of 10140 slaughtered beef calves during march 1995-june 1996 period. gross lesions were mainly lobular and occasionally lobar pattern and, were frequently observed in the pars cranialis of lobus cranialis dexter. in histological examination, proliferative-exudative pneumonia was observed in 79 cases, and proliferative pneumonia alone in 21 cases. in bacteriological examination, pasteurella haemolytica. pasteur ...19979151475
further studies of the relationships among strains classified as taxon 15, taxon 18, taxon 20, (pasteurella) granulomatis or the (pasteurella) haemolytica-complex in ruminants using quantitative evaluation of phenotypic data.ninety-three trehalose-negative (p.) haemolytica-like strains of ruminant, porcine and leprine origin were investigated. a quantitative evaluation of phenotypic tests was used and the results obtained were compared with those from 246 previously investigated ruminant strains. cluster analysis of the results obtained displayed most of the taxa as distinct groups which could be related to differences in key characters. although only minor phenotypic differences were observed between the taxa inves ...19979361379
genotypic relationships among strains classified under the (pasteurella) haemolytica-complex as indicated by ribotyping and multilocus enzyme electrophoresis.two-hundred and one strains classified under the (pasteurella) haemolytica-complex isolated from cattle, sheep, deer, pigs, hares and rabbits were investigated by ribotyping. fifty-nine of these strains were selected for further studies using multilocus enzyme electrophoresis (mee). a correlation between the clusters identified by ribotyping and mee was demonstrated and the results furthermore indicated that a genetic basis exists for most clusters previously outlined by the use of quantitative ...19979361380
effects of pasteurella haemolytica leukotoxin and lipopolysaccharide on histamine, prostanoid, and leukotriene release by bovine lung parenchyma in vitro.to identify the effect of pasteurella haemolytica lipopolysaccharide (lps) and leukotoxin (lkt) on spontaneous and calcium ionophore-induced histamine and inflammatory mediator release from isolated bovine lung parenchyma.19979361883
bovine respiratory tract disease caused by bovine viral diarrhea virus.although several viruses and bacteria are capable of inducing bovine respiratory tract disease, a pivotal organism in the cause of this complex disease may be bovine viral diarrhea virus (bvdv). circumstantial evidence has long supported this hypothesis. it is frequently present in diseased respiratory tract tissues often together with other viruses or bacteria. field observations suggest marked synergism occurs. researchers have confirmed that, in most instances, the virus itself elicits only a ...19979368990
bacterial pneumonia.bacteria play a critical role in the severe pneumonia and fatalities associated with the bovine respiratory disease complex. although numerous bacteria have the potential to cause pneumonia, only a small number of these are responsible for the majority of cases of disease. virulence and immunogenic characteristics of these organisms are important determinants of the host response to infection. these bacterial characteristics are reviewed and applied to a discussion of the epidemiology, pathogene ...19979368991
bacterial ghosts as multifunctional vaccine particles.expression of cloned phix174 gene e in gram-negative bacteria results in lysis of the bacteria by formation of an e-specific transmembrane tunnel structure built through the cell envelope complex. bacterial ghosts have been produced from a variety of bacteria including escherichia coli. salmonella typhimurium, salmonella enteritidis, vibrio cholerae, klebsiella pneumoniae, actinobacillus pleuropneumoniae, haemophilus influenzae, pasteurella haemolytica, pasteurella multocida, and helicobacter py ...19979382740
evaluation of a multivalent pasteurella haemolytica vaccine in bighorn sheep: safety and serologic responses.we examined effects of a multivalent pasteurella haemolytica vaccine (serotypes a1, a2, t10) on humoral immune responses and p. haemolytica isolation rates in bighorn sheep (ovis canadensis). thirty captive bighorns, divided into groups of three on the basis of age, sex, and previous history of pneumonic pasteurellosis, received 0, 1, or 2 vaccine doses. mild, transient lameness in most bighorns 1 day after initial vaccination was the only adverse effect observed. oropharyngeal (> or = 75%) and ...19979391957
characterization of the pasteurella haemolytica transferrin receptor genes and the recombinant receptor proteins.the tbpa and tbpb genes encoding the transferrin receptor proteins, tbpa and tbpb, from pasteurella haemolytica a1 were cloned, sequenced and expressed in escherichia coli. the genes were organized in a putative operon arrangement of tbpb- tbpa. the tbpb gene was preceded by putative promoter and regulatory sequences, and followed by a 96 base pair intergenic sequence in which no promoter regions were found, suggesting that the two genes are coordinately transcribed. the deduced amino acid seque ...19979405205
purification and characterization of a 31-kilodalton iron-regulated periplasmic protein from pasteurella haemolytica a1.a prominent iron-regulated periplasmic protein was purified from pasteurella haemolytica grown in an iron-deficient chemically defined medium. the protein was purified by anion exchange chromatography and appeared as a single band by sds-page with a molecular weight of 32,000. a yield of five mg was obtained from 91 mg of protein extract. the iron-regulated protein existed as a monomer in the native state with an average molecular weight of 29,877 as determined by analytical ultracentrifugation. ...19979413558
an outbreak of pasteurella multocida pneumonia in lambs during a field trial of a vaccine against pasteurella haemolytica.a vaccine against pneumonic pasteurellosis was evaluated for efficacy at two dilutions in lambs transported by sea from new zealand to saudi arabia. the experimental vaccine was a killed pasteurella haemolytica serotype a1 and a2 preparation. there was no evidence of either dilution of the vaccine leading to a lower pneumonia death or lesion rate than for the control group. however, bacteriological examinations to establish the causality of the pneumonia cases showed pasteurella multocida to be ...199716031950
preparturient vaccination to enhance passive immunity to the capsular polysaccharide of pasteurella haemolytica a1.the potential to increase passive serum antibody titres to a polysaccharide antigen in neonates, by preparturient vaccination of the dams was investigated. dairy cows in five private herds were vaccinated with a commercial pasteurella haemolytica culture supernatant vaccine (presponse, langford inc.), at 6 and 3 weeks before their calculated due dates. dams' sera, colostral whey, and post-colostral calf sera were assayed for antibodies of the igg1 isotype binding purified capsular polysaccharide ...19969157687
effects of interactions between pasteurella haemolytica and bordetella parapertussis on in vitro phagocytosis by lung macrophages.the aim of the work was to determine the effect of exposing ovine bronchoalveolar macrophages (bam) in vivo to pasteurella haemolytica and/or bordetella parapertussis on the subsequent uptake and killing of p. haemolytica by these cells in vitro. exposure in vivo to p. haemolytica did not affect the uptake of p. haemolytica by bam in vitro but reduced (p < 0.05) the intracellular killing of bacteria. exposure in vivo to b. parapertussis had no significant effect on either the uptake or killing o ...19969088547
susceptibility of dall sheep (ovis dalli dalli) to pneumonia caused by pasteurella haemolytica.we evaluated susceptibility of dall sheep (ovis dalli dalli) to bacterial pneumonia induced by two strains of pasteurella haemolytica of domestic sheep origin by evaluating the sensitivity of blood neutrophils of eight dall sheep to lysis by cytotoxins of p. haemolytica, and by intratracheal inoculation of three dall sheep, two bighorn sheep (ovis canadensis), and two domestic sheep with 3.7 x 10(6) or 2.5 x 10(7) colony forming units of p. haemolytica. neutrophils from the dall sheep were more ...19969359056
experimental contact of bighorn sheep (ovis canadensis) with horses and cattle, and comparison of neutrophil sensitivity to pasteurella haemolytica cytotoxins.peripheral blood neutrophils from horses, cattle, and rocky mountain bighorn sheep (ovis canadensis canadensis) were evaluated for susceptibility to cytotoxin-dependent lysis of different biotypes and serotypes of pasteurella haemolytica of domestic sheep, cattle, bighorn sheep, or mountain goat (oreamnos americana) origin utilizing a cytotoxicity assay which measures the degree of bacteria cytotoxin-killing of neutrophils. all isolates of p. haemolytica (biotypes a and t) were noncytotoxic to h ...19969359057
effects of bhv-1 on pmn adhesion to bovine lung endothelial cells.bovine herpes virus-1 (bhv-1) infection appears to decrease the rate of polymorphonuclear leukocyte (pmn) influx into the lung in response to the secondary invader, pasteurella haemolytica. it was postulated that bhv-1 may affect the rate of cellular infiltration by altering the function of the endothelium, thereby preventing pmn movement across the blood-tissue barrier. therefore, we decided to investigate the effect of bhv-1 on the ability of pmn to adhere to lung endothelial cells (lec). lec ...19969014307
[development of resistance in infectious agents of agricultural animals in germany (1990-1994)--a review].antibiograms received from veterinary laboratories during the 1990-1994 period were recorded and evaluated with the aid of a computer program. based on 70 tables giving information about th most important pathogens, the resistance behaviour of e. coli in cattle, swine, chicken, and turkey, that of pasteurella haemolytica and p. multocida in cattle and swine and that of staphylococcus aureus and streptococcus agalactiae in cattle have been in synoptic form. attention is drawn to the increase in r ...19968998938
[resistance pattern of bovine pasteurella].the sensibility of 375 pasteurellae of bovine origin (215 pasteurella multocida--and 160 pasteurella haemolytica--strains) was examined against 16 antibiotics or chemotherapeutics by agar diffusion technique. a great part of the strains was resistant to oxacillin (41,18%), tylosin (79,14%), streptomycin (53,21%), sulfonamides (57,33%) and tetracycline (47,20%). only a few resistant strains were found for cephalothin (5,07%), polymyxin b (0,27%) and enrofloxacin (0,53%). while 16,27% of all isola ...19968694744
pasteurella haemolytica leukotoxin induces bovine leukocytes to undergo morphologic changes consistent with apoptosis in vitro.infection of the bovine lung with pasteurella haemolytica results in an acute respiratory disorder known as pneumonic pasteurellosis. one of the key virulence determinants used by this bacterium is secretion of an exotoxin that is specific for ruminant leukocytes (leukotoxin). at low concentrations, the leukotoxin can activate ruminant leukocytes, whereas at higher concentrations, it inhibits leukocyte functions and is cytolytic, presumably as a result of pore formation and subsequent membrane p ...19968698496
in vitro expression and inhibition of procoagulant activity produced by bovine alveolar macrophages and peripheral blood cells.local and systemic activation of coagulation is frequently associated with bacterial sepsis. the coagulopathy is due, at least in part, to expression of tissue factor (tf) by monocytes and macrophages. the purpose of this study was to evaluate the expression of procoagulant activity by bovine alveolar macrophages, leukocytes and platelets, and to determine the relative potency of three chemical inhibitors of tf expression (pentoxifylline, retinoic acid, and cyclosporin a). bovine alveolar macrop ...19968950833
passage of cd18- and cd18+ bovine neutrophils into pulmonary alveoli during acute pasteurella haemolytica pneumonia.cd18 is a subunit for three beta 2 integrin molecules (mac-1, p150, 95, lfa-1), which are expressed on the plasma membrane of neutrophils. these molecules mediate passage of neutrophils into sites of infection. in children and animals that lack cd18 expression, neutrophil infiltration is impaired in most tissues. however, in lung, cd18- neutrophils have been identified in the airway spaces during spontaneous episodes of pneumonia. to determine whether cd18 is vital for passage through the pulmon ...19968952022
rapid identification and cloning of bacterial transferrin and lactoferrin receptor protein genes.the sequences of genes encoding the transferrin and lactoferrin receptor proteins from several bacterial species were analyzed for areas of identity in the predicted protein sequences. degenerate oligonucleotide primers were designed and tested for their ability to amplify portions of the receptor genes. primer pairs capable of amplifying products of the tbpa/lbpa or tbpb/lbpb genes from all species possessing these receptors were identified.19968955421
an epidemiological study into risk indicators for pasteurella haemolytica related 'summer pneumonia' in lambs in the southern netherlands.risk indicators for pasteurella haemolytica related summer pneumonia in lambs in the netherlands were investigated using a mail questionnaire survey of 860 flocks. the response rate was 64% (n = 550). multivariate risk analysis indicated that taking sheep to sheep fairs, the purchase of sheep and/or lambs, the lack of possibility for indoor housing, and an increased flock size were associated with increased risk of occurrence of summer pneumonia in lambs of the home flock.19968903142
in vitro lymphocyte proliferative responses and gamma-interferon production as measures of cell-mediated immunity of cattle exposed to pasteurella haemolytica.cell-mediated immune mechanisms may play a role in the pathogenesis and prevention of pneumonia in cattle caused by pasteurella haemolytica serotype a1. to determine the circumstances required to stimulate and identify cell-mediated immune responses, calves were vaccinated with a commercial p. haemolytica bacterin or a live commercial p. haemolytica vaccine, or were infected intratracheally with virulent p. haemolytica. all calves were challenge-exposed intratracheally with p. haemolytica 31 d a ...19968904662
penetration of parenterally administered ceftiofur into sterile vs. pasteurella haemolytica-infected tissue chambers in cattle.the effect of bacterial infection on antibiotic activity and penetration of parenterally administered ceftiofur into implanted tissue chambers was studied in cattle. tissue chambers were implanted subcutaneously in the paralumbar fossae of eight calves (256-290 kg body weight). approximately 80 days after implantation, the two chambers on one side of each animal were inoculated with pasteurella haemolytica (10(6) cfu/chamber). eighteen hours after inoculation, ceftiofur sodium was administered i ...19968905572
species selectivity of new siderophore-drug conjugates that use specific iron uptake for entry into bacteria.siderophores selectively bind ferric iron and are involved in receptor-specific iron transport into bacteria. several types of siderophores were synthesized, and growth-promoting or inhibitory activities when they were conjugated to carbacephalosporin, erythromycylamine, or nalidixic acid were investigated. overall, 11 types of siderophores and 21 drug conjugates were tested against seven different bacterial species: escherichia coli, bordetella bronchiseptica, pasteurella multocida, pasteurella ...19968913474
validation of random amplified polymorphic dna assays by ribotyping as tools for epidemiological surveys of pasteurella from animals.two collections of strains of pasteurella were studied for epidemiological purposes by ribotyping and random amplified polymorphic dna (rapd) assays. these strains were isolated through two different structures of animal productions: cattle and rabbit. forty strains of p. haemolytica from cattle reared in independent breeding-herds belonged to only 3 ribotypes after digestion with hindiii and pvuii. no further discrimination of these strains was obtained by rapd assays. all these 40 strains show ...19968914254
isolation and purification of functional bovine lung mast cells (blmcs).purified pulmonary mast cells were obtained from bovine lung using a combination of enzymatic digestion of tissue, density gradient centrifugation using percoll, and centrifugal elutriation. in the initial procedure, lung tissue was enzymatically digested with collagenase, hyaluronidase, protease and elastase in three 30 min incubations at 37 degrees c. monodispersed cell suspensions contained between 2 and 6% mast cells. further purification of these mast cells by percoll gradients and elutriat ...19968919968
pneumonic pasteurellosis associated with pasteurella haemolytica in chipmunks (tamias sibiricus).a laboratory study was performed in order to identify the possible cause of death in chipmunks (tamias sibiricus) imported from china with respiratory disease. severe congestion, alveolar oedema and fibrinous pleuritis were observed. biochemical analyses identified the causative organism as pasteurella haemolytica. an in vitro susceptibility test using various antimicrobial agents revealed sensitivity to beta-lactams (ampicillin and amoxicillin) and streptomycin.19968919970
the restriction-modification system of pasteurella haemolytica is a member of a new family of type i enzymes.genes encoding the type i restriction-modification (r-m) system of the bovine pathogen, pasteurella haemolytica, have been identified immediately downstream of a locus that encodes a transcriptional activator of p. haemolytica leukotoxin expression. type i enzymes are encoded by three genes called hsdm, hsds and hsdr, and have fallen into three groups, called ia, ib and ic. hsds provides a sequence recognition function which in concert with hsdm forms an active methyltransferase (mtase). inclusi ...19968921897
the relation of ventilatory failure to pulmonary, respiratory muscle and central nervous system disturbances in calves with an experimentally produced pneumonia.to explore the pathophysiology of respiratory failure in an experimental pneumonia, a pasteurella haemolytica broth culture was injected intratracheally into 12 calves, which were then studied over a period of 10 h. measurements were made of inspired minute ventilation (ve), ventilatory pattern [inspiratory time (ti), expiratory time (te), respiratory rate (rr) and tidal volume (vt)], transdiaphragmatic pressure (pdi), occlusion pressure at the airway opening 100 milliseconds after onset of insp ...19968923232
detection of mycoplasma ovipneumoniae and pasteurella haemolytica antigens by an immunoperoxidase technique in pneumonic ovine lungs.four hundred twenty pneumonic lungs from lambs were examined for mycoplasma ovipneumoniae and pasteurella haemolytica by an immunoperoxidase technique using an extravidin-biotin-peroxidase complex method in formalin-fixed, paraffin-embedded sections. histologic examination of tissue sections revealed strong positive reactions in 60.9% and 68.3% of the lungs against m. ovipneumoniae and p. haemolytica, respectively. m. ovipneumoniae and p. haemolytica antigens were observed at the surface and/or ...19968826008
differences in the distribution of cd34 epitopes on normal haemopoietic progenitor cells and leukaemic blast cells.the cd34 molecule expressed on haemopoietic progenitor cells contains a large number of epitopes whose expression may be related to the maturation or function of the cells. monoclonal antibodies specific for different epitopes have been reported to detect different numbers of cd34+ leukaemic blast cells. we wanted to confirm this observation and study whether parallel findings could be observed for normal haemopoietic progenitor cells. the cells were immunophenotyped by flow cytometry with a ser ...19968826880
evaluation of a pcr for detection of actinobacillus pleuropneumoniae in mixed bacterial cultures from tonsils.a pcr for the detection of actinobacillus pleuropneumoniae was evaluated. all of 102 field, isolates of a, pleuropneumoniae reacted in the pcr by amplification of a 985 bp product. no pcr amplification product was observed when examining strains of a. ureae, a. capsulatus, a. hominis, a. equuli, a, rossii, a. suis, escherichia coli, bordetella bronchiseptica. streptococcus suis, pasteurella haemolytica, pasteurella multocida, haemophilus parasuis, haemophilus taxon minor group, haemophilus taxon ...19968828126
characterization of epitopes involved in the neutralization of pasteurella haemolytica serotype a1 leukotoxin.defined segments of the leukotoxin a gene (lkta) from an a1 serotype of pasteurella haemolytica were cloned into a plasmid vector and expressed as lacz alpha fusion proteins. these fusion proteins were electrophoresed in sds-page gels and their immunoblotting reactivities with several monoclonal antibodies characterized. the epitope recognized by a strongly neutralizing monoclonal antibody was localized to a 32 amino acid region near the c terminus of the leukotoxin a (lkta) molecule. the epitop ...19968828217
induction of nitric oxide production by bovine alveolar macrophages in response to pasteurella haemolytica a1.we assessed the kinetics of inducible nitric oxide synthase (inos) mrna expression and production of nitric oxide (no) in bovine alveolar macrophages (ams) stimulated with purified lipopolysaccharide (lps) from pasteurella haemolytica strain 12296. the effect of lps on inos gene expression was dose-dependent and was expressed maximally at 24 h after stimulation with 10 micrograms/ml of lps. production of no measured as secreted nitrite in supernatants took place in a time and dose-dependent mann ...19968831831
efficacy of a subcutaneously administered, ultraviolet light-killed pasteurella haemolytica a1-containing vaccine against transthoracic challenge exposure in goats.to determine the effectiveness of pasteurella haemolytica biovar a, serovar 1 (ph a1) killed by uv light and incorporated with an oil adjuvant or carriers.19968836369
lesions in lambs experimentally infected with ovine adenovirus serotype 6 and pasteurella haemolytica.twenty-five colostrum-deprived lambs reared in isolation were inoculated with a us variant of ovine adenovirus serotype 6 (oav-6) strain rts-151, pasteurella haemolytica, or a combination of the 2 agents. although severe pulmonary lesions were caused by each agent, the lesions were more severe and lasted longer with the combined infection. lesions induced by oav-6 alone developed 6-9 days after inoculation and lasted for 15 days, the length of the experiment. the lesions were characterized by su ...19968844571
minimum inhibitory concentration breakpoints and disk diffusion inhibitory zone interpretive criteria for tilmicosin susceptibility testing against pasteurella spp. associated with bovine respiratory disease.tilmicosin is a novel macrolide antibiotic developed for exclusive use in veterinary medicine. the first tilmicosin-containing product was approved to treat bovine respiratory disease associated with pasteurellae. the development of antimicrobial susceptibility testing guidelines for tilmicosin was predicated on the relationship of clinical efficacy studies that demonstrated a favorable therapeutic outcome, on pharmaco-kinetic data, and on in vitro test data, as recommended by the national commi ...19968844577
[cytolysins and homologous proteins produced by gram-negative bacteria. i. hemolysis and leukotoxins of escherichia coli, bordetella pertussis, pasteurella haemolytica and actinobacillus sp].cytolysins produced by gram-negative bacteria belong to the pore forming bacterial proteins. a branch of these toxins represents rtx family of proteins. the rtx (repeats in toxin) family name has been proposed based on the common presence of tandem copies of a nine-amino acid repeat (l-x-g-g-x-g-(n/d)-d-x). the paper presents the genetics, synthesis, secretion and cytolytic activity of these toxins.19968848425
evaluation of three experimental subunit vaccines against pneumonic pasteurellosis in cattle.the objective of this study was to evaluate the efficacy of three pasteurella haemolytica a1 derived experimental subunit vaccines against pneumonic pasteurellosis in cattle. the three vaccines were: (a) culture supernatant (cs) containing leukotoxin (lkt), lipopolysaccharide (lps) and capsular polysaccharide (cp); (b) sodium salicylate extract (sse) containing iron regulated outer membrane proteins (iromps), lps and cp; (c) and a combination of the above two. vaccine efficacy was defined in ter ...19968852412
tandem repeats of the tetramer 5'-caat-3' present in lic2a are required for phase variation but not lipopolysaccharide biosynthesis in haemophilus influenzae.a novel lipopolysaccharide (lps) biosynthesis gene, lic2b, which is required for the biosynthesis of a phase-variable lps structure expressed by haemophilus influenzae rm7004 is described. the product of this gene is homologous to lic2a and the recently described lps biosynthetic enzymes, lgtb from neisseria gonorrhoea and lgte from neisseria meningitidis, and lpsa from pasteurella haemolytica. of this family of enzymes only lic2a contains the repetitive tetrapeptide motif (sinq)(n) encoded by m ...19968861214
major outer membrane proteins of pasteurella haemolytica serovars 1-15: comparison of separation techniques and surface-exposed proteins on selected serovars.the sarkosyl method of obtaining outer membrane proteins (omps) from pasteurella haemolytica a1 was more efficient and less laborious than separating membranes by sucrose gradient centrifugation. more omps were recovered and major omps were present in greater concentrations in the sarkosyl-derived preparations. therefore, omps of p. haemolytica serovars 1-15 (serovars 3, 4, 10, and 15 being t biotypes and the remainder being a biotypes) were prepared by the sarkosyl method and compared by sds-pa ...19968870193
genetic and immunological analyses of a 38 kda surface-exposed lipoprotein of pasteurella haemolytica a1.pasteurella haemolytica serotype a1 is the bacterial pathogen most frequently isolated from the lungs of cattle with bovine respiratory disease. as part of a study to characterize p. haemolytica antigens which are important in eliciting resistance to pneumonic pasteurellosis, we have cloned and sequenced the gene encoding a 38 kda lipoprotein, lpp38. the deduced amino acid sequence of lpp38 is similar to those of the escherichia coli polyamine transport proteins potd (70%) and potf (33%). p. hae ...19968870194
the isolation of recombinant plasmids expressing secreted antigens of pasteurella haemolytica a1 and the characterization of an immunogenic 60 kda antigen.a collection of recombinant plasmids had been isolated which express secreted antigens of pasteurella haemolytica a1 likely to be important in protection. the recombinant escherichia coli clones were found to express the p. haemolytica a1 antigens by western immunoblot analysis, using sera from calves which had been vaccinated with presponse and were subsequently resistant to experimental challenge with p. haemolytica a1. detailed analysis of three of the recombinant plasmids (pgs1-17, pgs3-19 a ...19968870198
respiratory tract disease and mucosal colonization by pasteurella haemolytica in transported cattle.to follow incidence of pasteurella haemolytica (ph) in the upper respiratory tract of healthy calves at the farm and through the marketing process, and to determine the effect of vaccination on ph colonization of the upper respiratory tract and on the incidence of respiratory tract disease (rtd).19968874726
cat iii chloramphenicol resistance in pasteurella haemolytica and pasteurella multocida isolated from calves.chloramphenicol, which had been used extensively for antimicrobial veterinary therapy, was prohibited in europe in 1994. soon after it became available, resistance to this drug was detected, generally conferred by plasmids encoding inactivating enzymes, the chloramphenicol acetyltransferases (cat), in gram-negative as well as in gram-positive bacteria. in the last few years, resistance to antibiotics emerged in pasteurella strains from breeding herds and this evolution was followed by a national ...19968877534
the fractional inhibitory concentration index of antimicrobial agents for bacteria and mycoplasma isolated from the nasal swabs of cattle with respiratory diseases.we investigated the effect of thiamphenicol plus lincomycin (tp + lcm) and thiamphenicol plus tylosin (tp + ts) combinations using checker board method on the growth of pasteurella (p.) multocida, p. haemolytica and mycoplasma (m.) bovis by calculating the fractional inhibitory concentration index (fic index). the results showed that the fic indexes of the tp + lcm combination for p. multocida, p. haemolytica and m. bovis were 0.36 +/- 0.10, 0.72 +/- 0.09 and 0.81 +/- 0.18, respectively. the fic ...19968877979
effect of a combination of antimicrobial agents for the treatment of respiratory disease in cattle.clinical effect of the administration of thiamphenicol (tp) and tylosin (ts) on bovine respiratory disease was investigated. group i (n = 64) were administered tp (10 mg/kg) and ts (4 mg/kg), group ii (n = 26) were given tp (5 mg/kg) and ts (2 mg/kg). for the control, tp group (n = 25) were given 20 mg/kg of tp and ampicillin group (n = 23) were given 10 mg/kg of ampicillin. as a result, improvement of clinical findings was more rapid and the cure rate was significantly higher in group i compare ...19968877980
hemodynamic responses to pasteurella haemolytica inoculation in calves given type 2 serotonergic antagonist.the effects of saline (control, group c) and metrenperone (treated, group m) on systemic and pulmonary hemodynamics were determined in conscious 7- to 15-day-old calves after they were intratracheally inoculated with pasteurella haemolytica. metrenperone, a specific serotonin (5-hydroxytryptamine) receptor antagonist, was injected intramuscularly (100 micrograms.kg-1) 2 h after the calves were inoculated. central venous, pulmonary arterial and capillary wedge, and systemic arterial pressures wer ...19968884022
an immunohistochemical method of detecting mycoplasma species antigens by use of monoclonal antibodies on paraffin sections of pneumonic bovine and caprine lungs.lung samples from pneumonic lesions in cattle and goats, naturally or experimentally infected with strains of the mycoplasma mycoides cluster, were fixed in formalin and embedded in paraffin. an immunohistochemical technique using monoclonal or polyclonal antibodies was performed on tissue sections in order to detect mycoplasma antigens. four monoclonal antibodies (mabs), one (2a3) raised against m. mycoides ssp. mycoides small colony (sc) and large colony (lc), two (1d3 and 5e5) against m. myco ...19968885707
association of rtx toxins with erythrocytes.a critical step in the target cell attack by rtx cytotoxins is their association with target cells. a binding assay was used to study the association of the escherichia coli hemolysin protein (hlya) with erythrocytes. several parameters required for lysis by hlya were tested for their effects on its initial association with erythrocytes. the results demonstrate that hlya binding to target cells is independent of several structural components of the active toxin, including the n-terminal hydropho ...19968890223
in-vitro activity of ceftiofur against australian isolates of the family pasteurellaceae associated with respiratory disease in cattle and pigs. 19968894010
the sequence of a 20.3 kb dna fragment from the left arm of saccharomyces cerevisiae chromosome iv contains the kin28, mss2, pho2, pol3 and dun1 genes, and six new open reading frames.we report the sequence of a 20 300 bp dna fragment from the left arm of saccharomyces cerevisiae chromosome iv. this segment contains 13 complete open reading frames (orfs) and part of another orf, altogether covering 84.2% of the entire sequence, five of which correspond to the previously characterized kin28, mss2, pho2, pol3/cdc2 and dun1 genes. one putative protein, d2358p, shares considerable homology with an o-sialoglycoprotein endopeptidase from pasteurella haemolytica serotype a1. the put ...19968896274
isolation of an ovine pulmonary surfactant-associated anionic peptide bactericidal for pasteurella haemolytica.ovine pulmonary surfactant is bactericidal for pasteurella haemolytica when surfactant and bacteria mixtures are incubated with normal ovine serum. to isolate this component, surfactant (1 mg/ml) was centrifuged at 100,000 x gav, and the supernatant was fractionated by hplc. fractions were eluted with acetonitrile (10-100%)/0.1% trifluoracetic acid and tested for bactericidal activity. amino acid and sequence analysis of three bactericidal fractions showed that fraction 2 contained h-gdddddd-oh, ...19968552650
the pasteurella haemolytica o-sialoglycoprotein endopeptidase is inhibited by zinc ions and does not cleave fetuin.culture supernatants of pasteurella haemolytica a1 contain an o-sialoglycoprotein endopeptidase that cleaves human glycophorin a. this enzyme is inhibited by micromolar concentrations of zn2+. it can be separated from a neuraminidase activity in culture supernatants by ion-exchange chromatography. the neuraminidase activity can cause the de-sialation of the bovine soluble sialoglycoprotein, fetuin. however fetuin is not cleaved proteolytically either by culture supernatants from p. haemolytica a ...19968602834
cloning and characterization of the gale locus of pasteurella haemolytica a1.the enzyme udp-galactose 4-epimerase (gale) is involved in one of the major steps of galactose metabolism in bacteria. in many cases, gale is required for the biosynthesis of extracellular polysaccharide materials such as lipopolysaccharide (lps) and capsule. mutants defective in gale have been shown to exhibit reduced virulence. here we describe the cloning and characterization of the gale gene from the bovine pathogen pasteurella haemolytica a1. this was achieved by the complementation of a sa ...19968641792
identification of cd34+ subsets after glycoprotease selection: engraftment of cd34+thy-1+lin- stem cells in fetal sheep.epitopes on the cd34 molecule detected by some cd34 antibodies can be cleaved by a unique glycoprotease from pasteurella haemolytica, which cleaves only glycoproteins rich in o-linked glycans. a method to isolate cd34+ cells from adult bone marrow was developed subsequently, in which cd34+ cells were isolated in high purity and yield following immunomagnetic bead selection and detachment with the glycoprotease. using a variety of other cell-surface markers shown here to be insensitive to glycopr ...19968647230
attempted protection of bighorn sheep (ovis canadensis) from pneumonia using a nonlethal cytotoxic strain of pasteurella haemolytica, biotype a, serotype.between february and april, 1994, we tested the hypothesis that bighorn sheep (ovis canadensis canadensis) inoculated with a cytotoxic isolate of pasteurella haemolytica biotype a, serotype 11 (a11) could withstand challenge inoculation with a cytotoxic strain of p. haemolytica a2 of domestic sheep origin known to cause lethal pneumonia in bighorn sheep. on experimental day o, two bighorn sheep were inoculated intratracheally with 6 x 10(9) colony forming units (cfu) of a cytotoxic strain of p. ...19968722270
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