Matsumoto Kouji, Kusaka Jin, Nishibori Ayako, Hara Hiroshi
Department of Biochemistry and Molecular Biology, Graduate School of Science and Technology, Saitama University, 255 Shimo-ohkubo, Saitama 338-8570, Japan.
Mol Microbiol. 2006 Sep;61(5):1110-7. doi: 10.1111/j.1365-2958.2006.05317.x.
The recent development of specific probes for lipid molecules has led to the discovery of lipid domains in bacterial membranes, that is, of membrane areas differing in lipid composition. A view of the membrane as a patchwork is replacing the assumption of lipid homogeneity inherent in the fluid mosaic model of Singer and Nicolson (Science 1972, 175: 720-731). If thus membranes have complex lipid structure, questions arise about how it is generated and maintained, and what its function might be. How do lipid domains relate to the functionally distinct regions in bacterial cells as they are identified by protein localization techniques? This review assesses the current knowledge on the existence of cardiolipin (CL) and phosphatidylethanolamine (PE) domains in bacterial cell membranes and on the specific cellular localization of certain membrane proteins, which include phospholipid synthases, and discusses possible mechanisms, both chemical and physiological, for the formation of the lipid domains. We propose that bacterial membranes contain a mosaic of microdomains of CL and PE, which are to a significant extent self-assembled according to their respective intrinsic chemical characteristics. We extend the discussion to the possible relevance of the domains to specific cellular processes, including cell division and sporulation.
近年来，针对脂质分子的特异性探针的发展，促使人们在细菌膜中发现了脂质结构域，即脂质组成不同的膜区域。将膜视为拼凑物的观点，正在取代辛格和尼科尔森的流体镶嵌模型（《科学》1972年，第175卷，第720 - 731页）中固有的脂质均一性假设。如果膜具有复杂的脂质结构，那么就会产生关于其如何形成和维持以及其功能可能是什么的问题。脂质结构域与通过蛋白质定位技术所确定的细菌细胞中功能不同的区域有怎样的关系？这篇综述评估了关于细菌细胞膜中心磷脂（CL）和磷脂酰乙醇胺（PE）结构域的存在以及某些膜蛋白（包括磷脂合成酶）的特定细胞定位的现有知识，并讨论了脂质结构域形成的化学和生理可能机制。我们提出细菌膜包含CL和PE的微结构域镶嵌体，它们在很大程度上根据各自内在的化学特性进行自组装。我们将讨论扩展到这些结构域与特定细胞过程（包括细胞分裂和孢子形成）的可能相关性。
