Beier D, Fuchs T M, Graeff-Wohlleben H, Gross R
Lehrstuhl für Mikrobiologie, Theodor-Boveri-Institut für Biowissenschaften (Biozentrum), Universität Würzburg, Germany.
Microbiologia. 1996 Jun;12(2):185-96.
Bordetella pertussis, the causative agent of whooping cough, coordinately regulates the expression of its virulence factors in response to certain environmental stimuli. This coordinate regulation is accomplished by the bvg locus encoding the BvgS and the BvgA proteins, which are members of the two-component family of bacterial signal transducing proteins. The sensor protein BvgS shows an "unorthodox" domain structure, combining the characteristic communication modules both of the two component sensors and response regulators, each of which is indispensable for BvgS function. Although under global control of the BvgAS system, two subsets of virulence factors exemplified by the adhesin FHA and the toxins PTX and CYA exhibit, respectively, a differential mode of expression. This is reflected in a differential kinetics of transcriptional activation in vivo, and the different ability of the various virulence promoters to be expressed in the heterologous organism Escherichia coli. Evidence is accumulating that this differential regulation may be due to different affinities of the virulence promoters for the phosphorylated form of BvgA.
百日咳博德特氏菌是百日咳的病原体，它会根据特定的环境刺激来协调调节其毒力因子的表达。这种协调调节是由编码BvgS和BvgA蛋白的bvg基因座完成的，这两种蛋白是细菌信号转导蛋白双组分家族的成员。传感蛋白BvgS呈现出一种“非正统”的结构域结构，它结合了双组分传感器和应答调节因子的特征性通讯模块，这两个模块对于BvgS的功能都是不可或缺的。尽管在BvgAS系统的全局控制下，以粘附素FHA以及毒素PTX和CYA为代表的两个毒力因子亚组分别呈现出不同的表达模式。这体现在体内转录激活的不同动力学上，以及各种毒力启动子在异源生物体大肠杆菌中表达的不同能力上。越来越多的证据表明，这种差异调节可能是由于毒力启动子对磷酸化形式的BvgA具有不同的亲和力。
