BEHAVIOR OF BACTERIA--BIOCHEMISTRY AND GENETICS

运动细菌如大肠杆菌被某些 化学物质和其他排斥，这一过程被称为趋化性。在 此外，这些细菌被某些物理刺激所吸引， 被其他排斥：例如，1）光带来趋光性; 2） 温度，趋热性;和3）渗透压，趋热性。建议开展的工作 本申请旨在了解这些物理刺激如何起作用， 带来这些行为反应。 在化学物质的情况下，刺激被大约20种不同的 化学感受器这些传感器将信息发送到四个不同的传感器 被称为甲基接受趋化蛋白的MCP;在某些情况下， 化学感受器实际上是MCP。在一个被称为激发的过程中， MCP通过磷酸化或去磷酸化趋化性（Che）蛋白 告诉鞭毛是否逆时针旋转， 在吸引剂的情况下运行，或者是否顺时针旋转， 从而在驱虫剂的情况下引起翻滚。那么激励就是 关闭（即使引诱剂或驱避剂仍然存在） 这一过程被称为适应：这包括水平的变化。 MCP的甲基化。在物理刺激的情况下，这里报告的工作 这里提出的实验旨在找出这种相同的机制是否也 适用.似乎在某些情况下，它可能，而在其他情况下， 该机制被绕过。物理刺激已经并将继续 已经或将要确定，以及响应如何发生 阐明。 这里发现的机制将有望与 了解高等生物的神经生物学和行为，包括 伙计此外，神经系统疾病也许可以通过以下方式来理解： 在这里找到的结果。

Motile bacteria such as Escherichia coil are attracted by certain chemicals and repelled by others, a process known as chemotaxis. In addition, these bacteria are attracted by certain physical stimuli and repelled by others: for example, 1) light brings about phototaxis; 2) temperature, thermotaxis; and 3) osmolarity, osmotaxis. Work proposed in this application aims to understand how these physical stimuli function to bring about these behavioral responses. In the case of chemicals, the stimuli are sensed by some twenty different chemoreceptors. These send their information to four different transducers called Methyl-accepting Chemotaxis Proteins the MCPs; in some cases the chemoreceptors actually are the MCPs. In a process known as excitation, MCP by way of phosphorylated or dephosphorylated chemotaxis (Che) proteins tells the flagella whether to rotate counterclockwise and thus bring about running in the case of attractants, or whether to rotate clockwise and thus bring about tumbling in the case of repellents. Then excitation is shut off (even though the attractant or repellent is still present) by a process known as adaptation: This consists of a change in the level of methylation of MCP. In the case of physical stimuli, work reported here and experiments proposed here aim to find out if this same mechanism also applies. It appears that in certain cases it might while in other cases this mechanism is bypassed. Physical stimuli have been and will be identified, and how the responses occur have partially been or will be elucidated. The mechanisms discovered here will hopefully have relevance to understanding neurobiology and behavior in higher organisms, including man. Further, diseases of the nervous system can perhaps be understood by results of the kinds found here.