GENETICS OF FLAVIN DEHYDROGENASE-MEMBRANE INTERACTIONS

这项研究的目的是确定黄素脱氢酶如何 与鼠伤寒沙门氏菌的膜相互作用。这项工作将 重点关注两个主要主题： 1.对看跌期权操纵者的监管。PUT操纵子有一个独特的控制 由puta基因产物介导的机制。当外源时 是可用的，Puta蛋白结合到膜上，在那里它 起黄素脱氢酶的作用；但在没有脯氨酸的情况下，它 积聚在细胞质中，在那里它扮演着自体抑制者的角色。 确定脯氨酸脱氢酶如何控制自己的表达可能 帮助我们了解其他膜结合的调节蛋白是如何工作的。 此外，puta突变的调节特性提供了一种 膜相互作用突变体的遗传选择。 2.黄素脱氢酶-膜相互作用。黄素脱氢酶 必须与膜相关联，才能与 电子传输链。然而，目前还不知道它们是如何相互作用的 与膜或电子传输链的哪些组成部分 与直接交互。PUTA相互作用的遗传学研究 具有膜的蛋白质提供了一个模型系统来理解 蛋白质在体内与膜相互作用。蛋白质-蛋白质和 膜结合所需的蛋白质-脂质相互作用可以是 这是通过分离防止腐肉蛋白 结合到膜上。这些细菌的遗传和生化分析 突变者将指示需要哪种交互作用 黄素脱氢酶和膜电子传递链。是这样的 突变体应该提供对一般生物学问题的洞察，即如何 外周膜蛋白与膜相互作用。

The objective of this study is to determine how flavin dehydrogenases interact with the membrane in Salmonella typhimurium. This work will focus on two main topics: 1. Regulation of the put operon. The put operon has a unique control mechanism that is mediated by the putA gene product. When exogenous proline is available, the PutA protein binds to the membrane where it functions as a flavin dehydrogenase; but in the absence of proline, it accumulates in the cytoplasm where it acts as an autogenous repressor. Determining how proline dehydrogenase controls its own expression may help us understand how other membrane-bound regulatory proteins work. In addition, the regulatory properties of putA mutations provide a genetic selection for membrane interaction mutants. 2. Flavin dehydrogenase-membrane interactions. Flavin dehydrogenases must associate with the membrane in order to interact properly with the electron transport chain. However, it is not known how they interact with the membrane or what components of the electron transport chain they interact with directly. Genetic studies on the interaction of PutA protein with the membrane provides a model system for understanding how proteins interact with membranes in vivo. The protein-protein and protein-lipid interactions required for membrane association can be determined by isolation of mutants that prevent the PutA protein from binding to the membrane. Genetic and biochemical analysis of these mutants will indicate what kinds of interactions are required between flavin dehydrogenases and the membrane electron transport chain. Such mutants should provide insight into the general biological problem of how peripheral membrane proteins interact with the membrane.