RUI: Molecules that Modulate Motility in Bacillus subtilis

运动和趋化功能不仅是枯草芽孢杆菌在营养缺乏和有毒环境中对细胞生存至关重要的复杂行为，而且需要同源基因的多水平调控。然而，存在其他的生存策略，包括产孢子，而运动所需的结构的精细化对细胞来说在生物合成上是昂贵的。因此，鞭毛基因在枯草杆菌中的表达必须对细胞的全局状态敏感。该实验室正在进行的研究致力于了解监测细胞营养状态和控制鞭毛基因表达的遗传和分子机制。另一种保存生物合成能量的方法是通过FlgM对鞭毛基因的结构调节，鞭毛基因编码鞭毛细丝的主要成分。FlgM是一种抗Sigma因子，在连接细丝的多蛋白质结构功能组装完成之前，它会抑制鞭毛基因的表达。这种控制的分子性质，以及允许通过细菌结构抑制FlgM的机制，在细微芽孢杆菌中尚未确定。因此，本项目的重点是确定FlgM的控制及其形态发生调控的具体细节。这项工作有望为一种重要的细菌行为的营养和结构调控提供洞察力。此外，这些研究是旧金山州立大学生物系教育活动的重要组成部分，将有助于培养本科生和硕士研究生，他们中的许多人是科学界代表性较低的少数群体的成员。

Motility and chemotaxis functions are not only complex behaviors in Bacillus subtilis important to cell survival in nutrient deprived and toxic environments, but require multi-level regulation of the cognate genes. However, additional strategies for survival, including sporulation, exist, and the elaboration of the structures required for motility is biosynthetically costly to the cell. Therefore, flagellar gene expression in B. subtilis must be sensitive to the global state of the cell. On-going research in this laboratory is dedicated to understanding the genetic and molecular mechanisms that monitor the nutritional state of the cell and control flagellar gene expression. Another means of conserving biosynthetic energy is by structural regulation of the flagellin gene that encodes the main component of the flagellar filament by FlgM. FlgM is an anti-sigma factor that inhibits flagellin gene expression until the multi-protein structure that tethers the filament is functionally assembled. The molecular nature of this control, as well as the mechanism that allows for FlgM inhibition by a bacterial structure, has not been determined in B. subtlis. Therefore, this project is focused on defining the specifics of FlgM control, and of its morphogenetic regulation. This work promises to provide insight into nutritional and structural regulation of an important bacterial behavior. Further, these studies are an important part of the educational activities in the Biology department at San Francisco State University and will benefit the training of undergraduate and masters degree students, many of whom are members of underrepresented minority groups in science.