The Roles of RpoS and the Borrelia Oxidative Stress Regulator, BosR, in the Transmission of Relapsing Fever Spirochetes

在2014财年，我们启动了一个关于复发热螺旋体--赫氏疏螺旋体的项目。自从T.Schwan博士退休后，我们启动了一个项目，以继续他在了解赫氏杆菌关键毒力因子调控方面的工作。虽然Hermsii与Burgdorferi具有编码相同调控蛋白的基因(即RpoN、rpos、RpoD和BosR)，但该细菌对环境信号(如温度)的反应截然不同。 伯氏杆菌基因调控的一个标志是RpoN/rpos调控网络。这种调控级联协调伯氏杆菌成功传播所需的毒力因子的表达。然而，北美分离的所有复发热螺旋体菌株都不具有功能性的RpoN，这表明在B.hermsii中不存在RpoN/rpos调节级联。因此，我们最初的重点是开发必要的生化和遗传工具来研究依赖于rpos、rpoD和BosR的已知毒力因子(即VMP和VTP)在埃尔斯米氏杆菌中的基因调控。

During FY 2014, we have started a project on the relapse fever spirochete, Borrelia hermsii. Since the retirement of Dr. T. Schwan, we have initiated a project to continue his work in understanding the regulation of key virulence factors in B. hermsii. While B. hermsii has the genes encoding the same regulatory proteins as B. burgdorferi (i.e., RpoN, RpoS, RpoD and BosR), the responses of the bacterium to environmental signals, such as temperature, are dramatically different. A hallmark of gene regulation in B. burgdorferi is the RpoN/RpoS regulatory network. This regulatory cascade coordinates the expression of virulence factors required for the successful transmission of B. burgdorferi. However, all strains of relapsing fever spirochetes isolated in North America do not harbor a functional RpoN, suggesting that the RpoN/RpoS regulatory cascade does not exsist in B. hermsii. Therefore, our initial focus has been on developing the necessary biochemical and genetic tools to study the RpoS-, RpoD- and BosR-dependent gene regulation of known virulence factors (i.e., Vmp and Vtp) in B.hersmii.