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To analyze the described lysogenic conversion of Bordetella parapertussis to a Bordetella pertussis-like form we used the phage 134 to lysogenize a B. parapertussis strain. Southern blot analysis of the isolated ‘lysogens’ showed that they were not true lysogens, but rather chronically infected strains. These pseudo-lysogens did not show any changes in virulence properties compared with the parental strain. The only difference we could show was a change in the LPS-structure: the pseudolysogens had a rough LPS, like B. pertussis, whereas the parental B. parapertussis strain was smooth.  相似文献   

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Virulence factors of Bordetella pertussis   总被引:4,自引:0,他引:4  
Clearly, B. pertussis has evolved very elaborate mechanisms to maintain itself in the human host. Three different proteins (FHA, pertussis toxin and fimbriae) have been implicated in adherence. Furthermore, a number of toxins are produced (pertussis toxin, adenylate cyclase, dermonecrotic toxin, and tracheal cytotoxin) which destroy the clearance mechanisms of the respiratory tract, or suppress the immune response. There is evidence that B. pertussis may survive intracellularly, and the possibility that it is a facultative intracellular parasite should certainly be explored. The availability of a large number of cloned virulence genes, and a system to construct well defined mutants by allelic exchange (Stibbitz et al. 1986) will greatly facilitate the study of Bordetella virulence factors at the molecular level. It opens the possibility to construct avirulent strains, which are still able to colonize and stimulate the local immune response. Such strains may be used as live, oral vaccines, to present (heterologous) antigens to the mucosal immune system of the respiratory tract.  相似文献   

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Bacteriocin Produced by Bordetella pertussis   总被引:2,自引:0,他引:2       下载免费PDF全文
Of the 24 strains of Bordetella pertussis examined, 2 produced bacteriocins that inhibited the growth of all but 2 other strains of this species. The two strains producing the bacteriocin and the two resistant strains were rough, whereas all susceptible strains were smooth. The bacteriocin was not active on the B. parapertussis or B. bronchiseptica strains tested. These bacteriocins appeared to be protein in nature, since they were heat-labile and partially inactivated by trypsin. They were antigenic but the neutralizing antibodies did not precipitate the antigens. Absorption of the antiserum with homologous cell suspensions removed the agglutinating, but not the neutralizing, antibody.  相似文献   

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Bordetella pertussis exploits extracellular and intracellular niches in the respiratory tract and a variety of immune evasion strategies to prolong its survival in the host. This article reviews evidence of complementary roles for cellular and humoral immunity in protection. It discusses the effector mechanisms of bacterial elimination, the strategies employed by the bacteria to subvert protective immune responses and the immunological basis for systemic and neurological responses to infection and vaccination.  相似文献   

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Viability of Bordetella pertussis was preserved when glycerol broth suspensions were quick frozen and stored at -70 C for as long as 45 months.  相似文献   

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R-plasmid-mediated chromosome mobilization in Bordetella pertussis   总被引:2,自引:0,他引:2  
Antibiotic-resistant and auxotrophic mutants of Bordetella pertussis were isolated. These were used as recipients for the uptake from Escherichia coli of broad-host-range R plasmids R68.45, RP1, and RP1 and RP4 carrying transposons Tn501 and Tn7 respectively. B. pertussis transconjugants from these crosses were used as donors to mobilize StrR, NalR, thr+ and gly+ chromosomal markers to B. pertussis or to B. parapertussis recipient strains. The frequency of plasmid transfer varied and depended on the donor and recipient strains used. Differences in chromosome mobilization frequencies of individual markers were observed and appeared to depend on the presence or absence of transposons Tn501 and Tn7 on the plasmid. Linkage was detected between the gly+ and NalR markers.  相似文献   

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S. Toma  H. Lo  M. Magus 《CMAJ》1978,119(7):722-724
A study was done to determine the major antigenic factors of Bordetella pertussis strains isolated throughout Canada and whether these isolates have the same antigenic structure as the bacilli in the currently used vaccines. Testing for the major pertussis antigens, factors 1, 2 and 3, was conducted with 440 freshly isolated strains of B. pertussis received from seven canadian provinces between August 1976 and February 1978 and six batches of pertussis vaccine or immunizing agents containing pertussis vaccine. With the aid of specific antisera prepared in rabbits, the antigenic factors were detected by a slide agglutination technique. Almost all (98.9%) of the pertussis strains examined were serotype 1,3.All six batches of pertussis vaccine or immunizing agents containing pertussis vaccine proved to be rich in each of the three main pertussis agglutinogens.  相似文献   

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为扩大生产,采用500立升发酵罐培养无细胞百日咳菌苗,发现随着培养时间的延续,细胞浓度增高,培养液的pH值上升,PT、FHA活性、血凝效价逐渐增加、O2溶压下降、CO2溶压上升。pH值达82时,PT活性最高为300EU/ml,较现用扁瓶培养方法高5倍。pH值继续上升时,PT活性开始下降。FHA活性及血凝效价具有相似的变化。通过测定培养液pH值以确定收获时间,可获得富含PT、FHA、且活性均保持较高水平的培养液  相似文献   

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Bordetella pertussis growth phases during homogenous batch dynamic cultivation in the liquid medium as well as during the static cultivation on the solid medium were established. The maximal activity of agglutination reaction with antisera to B. pertussis agglutinogens 1, 2, and 3 was detected in bacterial culture at the end of exponential phase of growth. The activity of agglutination reaction decreased when cultures in stationary and death phases were used. During transition from exponential to death phase level of antibodies to agglutinogen 2 decreased by4 - 32 times. 2 - 4-fold decrease of antibodies level was observed when antiserum to agglutinogen 3 was used. Activity of agglutination reaction with antiserum to agglutinogen 1 was high and did not depend from phase of growth. When polyvalent antiserum to B. pertussis was used 4-fold decrease of antibody titers was observed in parallel with change of growth phases. Sera from rabbits immunized with B. pertussis cultures from the middle of exponential growth phase, the end of this phase, and begin of the death phase had high (maximal) level of agglutinating antibodies (6400), which was detected on 101 day after immunization with the former culture and on 31 day after immunization with either of the two latter cultures. To the end of experiment (292 day) titers decreased to 800, 3200, and 1600 respectively. These findings confirm an advisability of use of exponential growth culture for immunization of rabbits in order to obtain highly active diagnostic antisera to B. pertussis.  相似文献   

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Areexamination of phase IV Bordetella pertussis   总被引:2,自引:0,他引:2  
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Structure of Bordetella pertussis peptidoglycan.   总被引:4,自引:0,他引:4       下载免费PDF全文
Bordetella pertussis Tohama phases I and III were grown to the late-exponential phase in liquid medium containing [3H]diaminopimelic acid and treated by a hot (96 degrees C) sodium dodecyl sulfate extraction procedure. Washed sodium dodecyl sulfate-insoluble residue from phases I and III consisted of complexes containing protein (ca. 40%) and peptidoglycan (60%). Subsequent treatment with proteinase K yielded purified peptidoglycan which contained N-acetylglucosamine, N-acetylmuramic acid, alanine, glutamic acid, and diaminopimelic acid in molar ratios of 1:1:2:1:1 and less than 2% protein. Radiochemical analyses indicated that 3H added in diaminopimelic acid was present in peptidoglycan-protein complexes and purified peptidoglycan as diaminopimelic acid exclusively and that pertussis peptidoglycan was not O acetylated, consistent with it being degraded completely by hen egg white lysozyme. Muramidase-derived disaccharide peptide monomers and peptide-cross-linked dimers and higher oligomers were isolated by molecular-sieve chromatography; from the distribution of these peptidoglycan fragments, the extent of peptide cross-linking of both phase I and III peptidoglycan was calculated to be ca. 48%. Unambiguous determination of the structure of muramidase-derived peptidoglycan fragments by fast atom bombardment-mass spectrometry and tandem mass spectrometry indicated that the pertussis peptidoglycan monomer fraction was surprisingly homogeneous, consisting of greater than 95% N-acetylglucosaminyl-N-acetylmuramyl-alanyl-glutamyl-diaminopimelyl++ +-alanine.  相似文献   

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