Burkholderia mallei is the etiologic agent of glanders in solipeds and humans. Lipopolysaccharide (LPS) is a major component of cell envelop of this pathogen. O-antigen, the most external component of LPS, is a virule...Burkholderia mallei is the etiologic agent of glanders in solipeds and humans. Lipopolysaccharide (LPS) is a major component of cell envelop of this pathogen. O-antigen, the most external component of LPS, is a virulence factor and a protective antigen in many pathogenic bacteria. Two putative proteins named Wzm (integral membrane protein) and Wzt (hydrophilic ATP-binding protein) are believed to make up an ABC-2 transporter of B. mallei that facilitates transport of components of O-antigen from cytosol to outer-membrane. We studied the importance of wzt (encoding Wzt) to growth, LPS O-antigen profile, and pathogenicity of B. mallei. A wzt mutant strain was generated by deleting a portion of the wzt in B. mallei wild type strain ATCC 23344 by gene replacement. Compared to the wild type strain, the wzt mutant displayed slower growth in vitro and less lethality in CD1 mice when inoculated intraperitoneally. The 50% lethal doses (LD50) of the wild type and the wzt mutant strains were 5.9 × 105 and 9.1 × 105 cfu, respectively. CD1 mice inoculated with a non-lethal dose of the wzt mutant produced specific serum immunoglobulins IgG1 and IgG2a and were partially protected against challenge with 11.2 times LD50 of the wild type strain. These findings suggest that the wzt is required for optimal in vitro growth and pathogenesis of B. mallei, and a wzt mutant protects CD1 mice against glanders.展开更多
目的研究锌转运体(zinc transporter,Zn T)家族成员在小鼠胰岛内的分布与表达,为进一步探讨Zn T参与胰岛锌离子稳态的调节和糖尿病的发病机理奠定基础。方法应用实时荧光定量聚合酶链反应(Real time-PCR)和免疫组织化学方法检测Zn T1-Zn...目的研究锌转运体(zinc transporter,Zn T)家族成员在小鼠胰岛内的分布与表达,为进一步探讨Zn T参与胰岛锌离子稳态的调节和糖尿病的发病机理奠定基础。方法应用实时荧光定量聚合酶链反应(Real time-PCR)和免疫组织化学方法检测Zn T1-Zn T10 m RNA和蛋白在8-10周龄CD1小鼠胰腺中的表达水平及分布。结果Real time PCR结果显示,除Zn T10以外,Zn T1-Zn T 9 m RNA在CD1小鼠胰腺中均有表达,Zn T8 m RNA在胰腺中表达水平最高,Zn T3 m RNA在胰腺中表达最低,其余Zn Tm RNAs表达水平相近。免疫组织化学结果表明,Zn T1-5、Zn T7和Zn T8均在胰岛细胞的细胞质呈不同程度的免疫染色。结论多个Zn T家族成员在胰岛细胞中有表达,为探讨Zn T在糖尿病发病中的作用提供了理论基础。展开更多
文摘Burkholderia mallei is the etiologic agent of glanders in solipeds and humans. Lipopolysaccharide (LPS) is a major component of cell envelop of this pathogen. O-antigen, the most external component of LPS, is a virulence factor and a protective antigen in many pathogenic bacteria. Two putative proteins named Wzm (integral membrane protein) and Wzt (hydrophilic ATP-binding protein) are believed to make up an ABC-2 transporter of B. mallei that facilitates transport of components of O-antigen from cytosol to outer-membrane. We studied the importance of wzt (encoding Wzt) to growth, LPS O-antigen profile, and pathogenicity of B. mallei. A wzt mutant strain was generated by deleting a portion of the wzt in B. mallei wild type strain ATCC 23344 by gene replacement. Compared to the wild type strain, the wzt mutant displayed slower growth in vitro and less lethality in CD1 mice when inoculated intraperitoneally. The 50% lethal doses (LD50) of the wild type and the wzt mutant strains were 5.9 × 105 and 9.1 × 105 cfu, respectively. CD1 mice inoculated with a non-lethal dose of the wzt mutant produced specific serum immunoglobulins IgG1 and IgG2a and were partially protected against challenge with 11.2 times LD50 of the wild type strain. These findings suggest that the wzt is required for optimal in vitro growth and pathogenesis of B. mallei, and a wzt mutant protects CD1 mice against glanders.
文摘目的研究锌转运体(zinc transporter,Zn T)家族成员在小鼠胰岛内的分布与表达,为进一步探讨Zn T参与胰岛锌离子稳态的调节和糖尿病的发病机理奠定基础。方法应用实时荧光定量聚合酶链反应(Real time-PCR)和免疫组织化学方法检测Zn T1-Zn T10 m RNA和蛋白在8-10周龄CD1小鼠胰腺中的表达水平及分布。结果Real time PCR结果显示,除Zn T10以外,Zn T1-Zn T 9 m RNA在CD1小鼠胰腺中均有表达,Zn T8 m RNA在胰腺中表达水平最高,Zn T3 m RNA在胰腺中表达最低,其余Zn Tm RNAs表达水平相近。免疫组织化学结果表明,Zn T1-5、Zn T7和Zn T8均在胰岛细胞的细胞质呈不同程度的免疫染色。结论多个Zn T家族成员在胰岛细胞中有表达,为探讨Zn T在糖尿病发病中的作用提供了理论基础。
