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For the first time Bordetella pertussis bacteriophage was isolated, and its presence was confirmed by electron microscopy and by agar layer titration. The lysogenic strains were activated by their treatment with mitomycin C in a dose of 4.5 mg/ml. The phage system of the Bordetella genus, heretofore unknown, has been revealed: Bordetella pertussis phage lyzed all the tested strains of Bordetella parapertussis (25 strains) and could be passaged in these strains. The phage formed turbid and transparent negative colonies 0.1 mm and 0.15 mm in size. The phage titer (e. g., in strain No. 3865) was 1 X 10(10). The lysogenic variants of Bordetella pertussis, capable of spontaneous release of the phage, were obtained. These variants were characterized by changes in some of their phenotypical properties, e.g., the increased content of certain toxic substances and increased virulence.  相似文献   

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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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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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Administration of Bordetella pertussis and some of their components to mice induced an increase of DNA-binding activity of the sera revealed under ionic strength conditions of physiological saline, mostly on the 14th day. It was shown by the inhibition method that interaction between mouse sera and native DNA was specific. Maximum increase in the quantity of mouse sera proteins reacting with DNA under low ionic strength condition of physiological saline (0.05 M NaCl) is revealed on the 7th day. However, in administration of Bordetella pertussis and their cytoplasmic membrane the elevated DNA-binding proteins content persisted up to 14 days.  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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The authors studied the antigenic activity of Bordetella pertussis during stab cultivation. For the first time there were revealed changes (oscillations) of antigenic activity: formation of 3 peaks of which the middle was the highest. A possibility of improving the quality of pertussis vaccine by using biomass at the height of the peak was experimentally founded.  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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