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1.
Plasmid DNA screening experiments were conducted to determine whether a relationship existed between the presence of plasmids and antibiotic resistance in Pasteurella haemolytica or the capability to produce hemolysin or leukotoxin (cytotoxin). Regardless of plasmid content, all P haemolytica isolates produced characteristic hemolysis on blood agar plates. Similarly, standardized suspensions of living bacteria and sterile concentrated (approx 200:1) culture supernatant from strains representing each of the 15 recognized P haemolytica serotypes and 7 field strains of P haemolytica (biotype A, serotype 1) produced leukotoxin, which was detected by their capability to cause inhibition of the luminol-dependent chemiluminescence response of bovine neutrophils. However, neither living bacterial suspensions nor concentrated culture supernatant from 4 untypable P haemolytica strains or a P multocida strain caused an inhibition of the luminol-dependent chemiluminescence response. The production of neither hemolysin nor leukotoxin by P haemolytica seemed to be plasmid mediated. Leukotoxin production is apparently a stable phenotypic characteristic of pathogenic P haemolytica strains, and the gene(s) coding for this activity is probably located on the bacterial host chromosome. Antibiotic susceptibility profiles were determined for the different bacterial strains. Studies of ampicillin and penicillin resistance in 8 P haemolytica (biotype A, serotype 1) strains provided evidence that the plasmid, with size of approximately 5,200 base pairs, may code for their resistance to these compounds. 相似文献
2.
Pasteurella species isolated from the bovine respiratory tract and their antimicrobial sensitivity patterns 总被引：3，自引：0，他引：3
Pasteurella haemolytica biotype A, serotype 1 (P haemolytica A1) was the most commonly isolated Pasteurella species from 80 calves examined at necropsy from 40 outbreaks of respiratory disease, the majority of which were pathologically confirmed as bovine pneumonic pasteurellosis (transit fever; shipping fever). Similarly, nasopharyngeal swabs from in-contact and apparently healthy calves indicated the widespread presence of P haemolytica A1. Pasteurella multocida and other serotypes of P haemolytica A1 were found including six isolations of P haemolytica T10, a fairly common pathogen in sheep. Approximately two-thirds of the isolates were tested for their antimicrobial sensitivity patterns and the degree of sensitivity for P haemolytica A1, the most frequently isolated serotype, was chloramphenicol (100 per cent), sulphamethoxazole trimethoprim (98 per cent), oxytetracycline (80 per cent), ampicillin (85 per cent), penicillin (82 per cent), streptomycin (3 per cent) and lincomycin (1 per cent). 相似文献
3.
One hundred and fifty-three bovine Pasteurella multocida strains recovered primarily from cases of pneumonia and mastitis in England and Wales over an 11-year period were characterised by capsular PCR typing, comparison of outer membrane protein (OMP) profiles, and multilocus sequence analysis. All of the strains were of capsular type A with the exception of a single capsular type F isolate. Thirteen distinct OMP profiles (OMP-types) were identified based mainly on molecular mass heterogeneity of the heat-modifiable (OmpA) and porin (OmpH) proteins. However, 85% of the isolates were represented by just five OMP-types and 39% of the strains were of a single OMP-type. Multilocus sequence analysis revealed a limited degree of genetic diversity among bovine P. multocida isolates; strains of the same OMP-type have identical genetic backgrounds and represent distinct clones. Analysis of OMP variation was more discriminating than multilocus sequence analysis because strains of different OMP-types had the same, or similar, genetic backgrounds. The association of a small number of clones with the majority of cases of bovine pneumonia suggests that these clones have an increased capacity to cause disease compared to less frequently recovered clones. Molecular mass heterogeneity of OmpA and OmpH, in strains of the same or similar genetic background, suggests that these proteins are subject to diversifying selection within the host and might play important roles in host-pathogen interactions. Comparison of the OMP profiles of bovine isolates with those of avian, ovine and porcine strains showed that a high proportion of the respiratory tract infections in each of these species are caused by different strains of P. multocida. However, the presence of small numbers of closely related strains in more than one host species suggests that transmission of bacteria between different host species is also a factor in the population biology of P. multocida. 相似文献
4.
Pasteurella multocida and bovine respiratory disease 总被引：1，自引：0，他引：1
Dabo SM Taylor JD Confer AW 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2007,8(2):129-150
Pasteurella multocida is a pathogenic Gram-negative bacterium that has been classified into three subspecies, five capsular serogroups and 16 serotypes. P. multocida serogroup A isolates are bovine nasopharyngeal commensals, bovine pathogens and common isolates from bovine respiratory disease (BRD), both enzootic calf pneumonia of young dairy calves and shipping fever of weaned, stressed beef cattle. P. multocida A:3 is the most common serotype isolated from BRD, and these isolates have limited heterogeneity based on outer membrane protein (OMP) profiles and ribotyping. Development of P. multocida-induced pneumonia is associated with environmental and stress factors such as shipping, co-mingling, and overcrowding as well as concurrent or predisposing viral or bacterial infections. Lung lesions consist of an acute to subacute bronchopneumonia that may or may not have an associated pleuritis. Numerous virulence or potential virulence factors have been described for bovine respiratory isolates including adherence and colonization factors, iron-regulated and acquisition proteins, extracellular enzymes such as neuraminidase, lipopolysaccharide, polysaccharide capsule and a variety of OMPs. Immunity of cattle against respiratory pasteurellosis is poorly understood; however, high serum antibodies to OMPs appear to be important for enhancing resistance to the bacterium. Currently available P. multocida vaccines for use in cattle are predominately traditional bacterins and a live streptomycin-dependent mutant. The field efficacy of these vaccines is not well documented in the literature. 相似文献
5.
The antimicrobial susceptibilities of 421 Pasteurella haemolytica and 158 P. multocida isolates recovered from cattle with respiratory disease were determined with a microdilution minimal inhibitory concentration test system. Isolates were analyzed for patterns of resistance to ampicillin, ceftiofur, erythromycin, gentamicin, penicillin, spectinomycin, sulfachlorpyridazine, sulfadimethoxine, tetracycline, and tylosin. All isolates tested were found susceptible to ceftiofur and sulfachlorpyridazine. Pasteurella haemolytica isolates were resistant to ampicillin, penicillin, sulfadimethoxine, tetracycline, and tylosin. Pasteurella multocida isolates were resistant to sulfadimethoxine, tetracycline, and tylosin. 相似文献
6.
7.
Purification and partial characterization of a macrophage cytotoxin from Pasteurella haemolytica 总被引：19，自引：0，他引：19
M E Himmel M D Yates L H Lauerman P G Squire 《American journal of veterinary research》1982,43(5):764-767
A protein from Pasteurella haemolytica that was highly immunogenic and toxic toward bovine alveolar macrophages was partially purified. When isolated from culture supernatants of P haemolytica serotype 1 or serotype 6, the protein reacted on Ouchterlony immunodiffusion tests with antisera from 12 serotypes of P haemolytica, but did not cross-react with antisera to serotypes of P multocida. This indicated that the protein may be specific for P haemolytica. Bacteria were grown in dialysis culture in a brain-heart infusion and calf-serum growth medium. The protein was isolated from the medium by ultrafiltration and size-exclusion chromatography and has a molecular weight of approximately 150,000 daltons. The protein, which is highly immunogenic and has the characteristics of a virulence factor, is common to all serotypes of P haemolytica, and may be an effective agent for immunization against P haemolytica in cattle. 相似文献
8.
Pasteurella haemolytica isolates, obtained from cattle with respiratory tract disease, were characterized as to serotype, antimicrobial susceptibility, and plasmid content. Strains isolated from 2 groups of cattle were compared. Remarkable similarity was seen in the plasmid profiles of isolates of the same serotype. In contrast, isolates of 2 different serotypes had totally different plasmid profiles. 相似文献
9.
Multiple drug resistance in Pasteurella multocida and Pasteurella haemolytica from cattle and swine. 总被引：10，自引：0，他引：10
The results of antimicrobial susceptibility testing on 262 strains of Pasteurella multocida and 141 strains of Pasteurella haemolytica isolated from cattle and swine from 1971 to 1974 were analyzed for patterns of resistance to streptomycin, penicillin, tetracycline, and chloramphenicol, using a modified Kirby-Bauer procedure. Resistance was recorded for 80.5% of the isolants of P multocida and 92.2% of those of P haemolytica. Resistance to streptomycin was most frequent, followed by resistance to penicillin and tetracycline. Most cultures of P multocida and P haemolytica were susceptible to chloramphenicol. There were 9 patterns of resistance with the aforementioned antibiotics. The combinations, streptomycin and penicillin and streptomycin and tetracycline, each accounted for approximately 10% of the resistance patterns of P multocida. Approximately half of the 14 isolants of P haemolytica were resistant to the combination of streptomycin, penicillin, and tetracycline. These observations underscore the need for antimicrobial susceptibility testing of clinical isolants of P multocida and P haemolytica. 相似文献
10.
Geschwend G Feist H Erler W 《Berliner und Münchener tier?rztliche Wochenschrift》1997,110(10):386-390
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 possess binding positions for iron ions. Both Pasteurella multocida and Pasteurella haemolytica strains utilize iron from porcine and bovine transferrin, but not from haemin and haemoglobin. 相似文献
11.
Resistance to trimethoprim and 2,4-diamino-6,7-diisopropyl-pteridine (0/129) in Pasteurella haemolytica 总被引：1，自引：0，他引：1
Thirteen strains of Pasteurella haemolytica resistant to moderate levels of trimethoprim (MICs from 8 to 64 micrograms/ml) and 0/129 (MICs from 16 to 64 micrograms/ml) were isolated from bovine specimens. Two strains, CNP330 and CNP334, were studied and found to harbour various plasmids but all attempts to cure trimethoprim resistance were unsuccessful. Resistance characters were not transferable to Escherichia coli or to Pasteurella multocida by conjugation and to E. coli by transformation. The resistance gene(s) was therefore tentatively assigned to a chromosomal location and cloned into E. coli where it conferred trimethoprim resistance. Trans-complementation analysis of a dihydrofolate reductase-deficient mutant of E. coli showed that trimethoprim resistance was secondary to synthesis of a dihydrofolate reductase. DNA/DNA hybridization of the hybrid plasmid and of strains CNP330 and CNP334 with probes specific for dihydrofolate reductase types I to V were negative, indicating that cross-resistance to trimethoprim and 0/129 in P. haemolytica was due to the acquisition by P. haemolytica of a new resistance determinant. 相似文献
12.
From 1940 through 1978, fifty-eight strains of Pasteurella multocida (serotype 3) were isolated from turkeys throughout the United States and were examined for R-plasmids. Forty-one of the isolates contained plasmid DNA, of which 7 isolates were found to encode resistance to tetracycline, streptomycin, and sulfonamides, or to streptomycin and sulfonamides. The R-plasmids were 2 to 10 megadaltons, nonconjugal, and contained a moles percent guanine plus cytosine ratio in the range of 57 to 61. The R-plasmids did not belong to any of the 19 incompatibility groups evaluated, including Inc Q. Digestion with restriction endonuclease indicated that 2 of the plasmids from P multocida isolated in 1960 and 1962 were identical, whereas 4 of the 5 plasmids obtained from P multocida isolated after 1966 were identical, with the 5th plasmid closely related to the other 4. The results indicated that R-plasmids were not widely dispersed among P multocida (serotype 3) isolated from turkeys in the United States. The nontransmissible nature of these plasmids was probably the major reason for their lack of dissemination. 相似文献
13.
The production and characterization of monoclonal antibodies against Pasteurella haemolytica serotype 1 is described. Ten monoclonal antibodies were produced and divided, on the basis of their properties, into six different groups. One produced bacteria agglutination only of P. haemolytica serotype 1. Three antibodies bound with P. haemolytica serotypes 1, 5-8 and 12 and the antigen was identified in immunoblots as lipopolysaccharide. Two antibodies bound P. haemolytica serotypes 1, 2, 5-8 and 12 and P. multocida serotypes 1-7, 9, 12, 15 and 16, recognizing an epitope present on a 29 kDa outer membrane protein. One antibody bound all P. haemolytica and P. multocida serotypes. The antigen was a hexosamine less than 30 kDa which contained a formalin sensitive epitope. One antibody bound only to P. haemolytica serotype 1 and the antigen was identified as a 66 kDa outer membrane protein. Two antibodies bound P. haemolytica serotypes 1, 2, 5-9 and 12 and the antigen, while not identified, was localized on the outer membrane. This study identified antigens which contribute to the cross-reactions among P. haemolytica and P. multocida serotypes and the antibodies may be useful in investigating the pathogenesis of pneumonic pasteurellosis. 相似文献
14.
Genomic distribution of a serotype 1-specific antigen-coding DNA fragment of Pasteurella haemolytica. 总被引：1，自引：0，他引：1
C Gonzalez M P Murtaugh S K Maheswaran 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1991,38(8):599-609
A genomic fragment of Pasteurella haemolytica biotype A coding for a serotype 1-specific agglutinating antigen was used as a probe in a series of hybridization experiments to determine distribution of the fragment in various P. haemolytica serotypes as well as other bacteria. Results showed presence of the fragment in seven out of the 12 serotypes tested, all of which belonged to biotype A. Two other serotypes belonging to biotype A, all three serotypes belonging to biotype T, two Pasteurella multocida isolates and Escherichia coli did not have the fragment in their genome. Thus the expression of the P. haemolytica biotype A serotype 1-specific agglutinating antigen (PHA1SAA) seems to be due to serotype-specific regulation of protein expression rather than to genetic deletion. Differences in methylation of the PHA1SAA-coding fragment was also noted in DpnI and Sau3AI genomic DNA digests from the various serotypes analyzed by Southern blot. However, no apparent correlation was observed between methylation and PHA1SAA expression. E. coli with a recombinant plasmid containing a homologous genomic fragment derived from P. haemolytica serotype 2 also expressed PHA1SAA. 相似文献
15.
Catry B Baele M Opsomer G de Kruif A Decostere A Haesebrouck F 《Veterinary microbiology》2004,98(3-4):251-260
tRNA-intergenic spacer PCR (tDNA-PCR) was evaluated for its effectiveness in differentiating Pasteurella and Mannheimia (sub)species predominantly of ruminant origin. For this purpose, 38 reference strains and 13 field isolates belonging to both genera were investigated. tDNA-PCR enabled discrimination of all Pasteurella species tested (Pasteurella (P.) aerogenes, P. avium, P. canis, P. lymphangitidis, P. multocida, P. trehalosi). For the differentiation of the subspecies of P. multocida, an additional dulcitol reaction was required. Two of the five so far-defined Mannheimia species, M. granulomatis and M. varigena, had a distinct fingerprinting profile. The remaining three phylogenetically highly related species (M. haemolytica, M. glucosida, and M. ruminalis) clustered together. Nevertheless, M. ruminalis is non-haemolytic, and M. haemolytica and M. glucosida can be differentiated on the basis of two additional phenotypic characteristics (beta-glucosidase and aesculin hydrolysis). In conclusion, tDNA-PCR is a useful tool in differentiating organisms belonging to the genera Pasteurella and Mannheimia. 相似文献
16.
为了解禽多杀性巴氏杆菌(Pasteurella multocida,Pm)分离菌株的荚膜血清型、菌体血清型与外膜蛋白型之间的相关性,首先对自行分离的10个菌株采用间接血凝试验和琼脂扩散试验进行鉴定(均为A:1);然后采用超声波破碎、高速离心和十二烷基肌氨酸钠提取外膜蛋白,通过SDS-PAGE电泳的方法对上述10个菌株与C48-1(A:1)、X73(A:1)、P1059(A:3)、CU(A:3,4)等一起进行外膜蛋白(Outer membrane proteins,OMP)分型研究。结果表明:14个禽多杀性巴氏杆菌菌株以2个主要蛋白OmpH和OmpA的差异为依据分为3种主要OMP型;依据次要蛋白的差异,OMP-1,3菌株进一步分为OMP型1.1,1.2和3.1,3.2,其中OMP型1.1有6个菌株,OMP型1.2有5个菌株;OMP型2有1株(YZ7031);P1059为OMP型3.1;CU为OMP型3.2;另外,血清型为A:1的12个菌株中有11个菌株外膜蛋白型均为OMP-1型,血清型为A:3、A:3,4的菌株外膜蛋白型属于3型。说明禽多杀性巴氏杆菌血清型与特定的外膜蛋白型具有很强的相关性。 相似文献
17.
Vaccination-challenge experiments were conducted in colostrum-deprived calves to evaluate the efficacy of Pasteurella bacterins and vaccines against experimental pneumonic pasteurellosis. Calves were vaccinated with formalin-killed bacterins and live vaccines, then challenge exposed intratracheally with P. haemolytica or P. multocida. Infectious bovine rhinotracheitis virus was inoculated intranasally three to four days prior to P. haemolytica challenge-exposure. All calves were examined for macroscopic and microscopic lesions after being found dead or following euthanasia four to seven days after challenge exposure with the bacterial pathogen. Clinical, hematological, and pathological responses to challenge exposure in aluminum hydroxide absorbed P. haemolytica and P. multocida bacterin-treated calves were consistent with the pneumonic lesions of pulmonary pasteurellosis in the control calves. An oil-adjuvanted P. haemolytica bacterin limited clinical and pathological responses in the affected calves whereas a P. multocida oil-adjuvanted bacterin did not. Both clinical and pathological responses to challenge exposure in calves vaccinated with live Pasteurella vaccines were less severe than those of the control calves. Vaccine effectiveness appeared to be dose dependent. 相似文献
18.
160 ovine isolates of Pasteurella haemolytica, representing each of the 16 serotypes and also untypable strains, were examined for plasmid content. Plasmid DNA was identified in, and prepared from, strains of serotypes A2, T3, A14 and A16 and also from an untypable strain. The relationship between the plasmids present in the different strains was examined both by restriction fragment profile analysis and by DNA/DNA hybridisation. Both methods gave broadly similar results and showed that each serotype tended to contain either a single plasmid species, or a limited range of species, and that structural similarities could traverse serotype boundaries. None of the plasmid-bearing strains showed any significant level of resistance to a range of antibiotics. 相似文献
19.
Carbon source assimilation and fermentation tests: study of 77 animal Pasteurella strains by a microtechnique 总被引：1，自引：0，他引：1
P Duclos J Freney J Caillet H Alexandre D Garonnat 《Comparative immunology, microbiology and infectious diseases》1986,9(1):47-51
77 strains of Pasteurella from various animal species were tested using the API micromethod for their ability to assimilate 147 carbon substrates and ferment 49 carbohydrates. Typical profiles of P. multocida and P. haemolytica were determined. This micromethod should prove useful in establishing the biotypes of Pasteurella species and in studying their epidemiology and pathogenicity. 相似文献
20.
Characterization of outer membrane protein-enriched extracts from Pasteurella multocida isolated from turkeys 总被引：1，自引：0，他引：1
Outer membrane protein (OMP)-enriched extracts of avian strains of Pasteurella multocida were examined by use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Culture medium did not have a significant effect on the OMP profiles of strains of P multocida examined; however, in vivo propagation had an appreciable effect on the OMP profile composition of the reference strain P-1059. Such bacteria, expressed several additional OMP in the 27-kD, 48-kD, 56-kD, 60-kD, 80-kD, and 94-kD molecular mass regions. These OMP were not detected in the electrophorogram of strain P-1059 grown in vitro. The OMP profiles of reference strains of the 16 serotypes of P multocida did not identify any serotype-specific protein markers. Field strains of serotype A:3 had variation in OMP profiles and did not express OMP that all were identical to that expressed by the reference strain P-1059. The live attenuated CU and M9 bacterial vaccine strains expressed strain-specific OMP markers of 48-kD and 45-kD molecular masses, respectively. These strain-specific OMP markers may be used to differentiate these strains from virulent field strains that are of the same serotype and isolated from turkeys that have succumbed to pasteurellosis as a result of vaccine-related reactions or breakdown in immunity. 相似文献