Charon Nyles W, Goldstein Stuart F
Department of Microbiology, Immunology, and Cell Biology, Health Sciences Center, West Virginia University, Box 9177, Morgantown, West Virginia 26506-9177, USA.
Annu Rev Genet. 2002;36:47-73. doi: 10.1146/annurev.genet.36.041602.134359. Epub 2002 Jun 11.
Spirochetes are a medically important and ecologically significant group of motile bacteria with a distinct morphology. Outermost is a membrane sheath, and within this sheath is the protoplasmic cell cylinder and subterminally attached periplasmic flagella. Here we address specific and unique aspects of their motility and chemotaxis. For spirochetes, translational motility requires asymmetrical rotation of the two internally located flagellar bundles. Consequently, they have swimming modalities that are more complex than the well-studied paradigms. In addition, coordinated flagellar rotation likely involves an efficient and novel signaling mechanism. This signal would be transmitted over the length of the cell, which in some cases is over 100-fold greater than the cell diameter. Finally, many spirochetes, including Treponema, Borrelia, and Leptospira, are highly invasive pathogens. Motility is likely to play a major role in the disease process. This review summarizes the progress in the genetics of motility and chemotaxis of spirochetes, and points to new directions for future experimentation.
螺旋体是一类在医学上具有重要意义且在生态方面具有显著意义的运动细菌，其形态独特。最外层是膜鞘，在该鞘内是原生质细胞圆柱体以及亚末端附着的周质鞭毛。在此，我们探讨其运动性和趋化性的特定及独特方面。对于螺旋体而言，平移运动需要两个位于内部的鞭毛束进行不对称旋转。因此，它们具有比经过充分研究的模式更为复杂的游动方式。此外，协调的鞭毛旋转可能涉及一种高效且新颖的信号传导机制。该信号将在细胞长度上传递，在某些情况下，细胞长度比细胞直径大100多倍。最后，许多螺旋体，包括密螺旋体、疏螺旋体和钩端螺旋体，都是高度侵袭性的病原体。运动性可能在疾病过程中起主要作用。本综述总结了螺旋体运动性和趋化性遗传学方面的进展，并指出了未来实验的新方向。
