Sharma Isha, Nagpal Sharon, Mishra Alok Kumar
Department of Microbiology, School of Bioengineering and Biosciences, Lovely Professional University, Phagwara, Punjab, India.
Folia Microbiol (Praha). 2025 Aug 9. doi: 10.1007/s12223-025-01301-4.
A ubiquitous property of bacteria is their ability to move toward more suitable environments, which can also facilitate host-associated activities like colonization and offer the cell several benefits such as bacteria moving towards a favorable gradient or away from a harmful gradient is known as chemotaxis. Bacteria achieve this by rotating flagella in clockwise and anticlockwise directions resulting in "run" and "tumble." This ability of bacteria to sense and respond to any type of change in the environmental factors like pH, osmolarity, redox potential, and temperature is a standard signal transduction system that depends on coupling proteins, which is the bacterial chemotaxis system. There are two architectures for the coupling proteins in the chemotaxis system: CheW and CheV. Typically, a signal transduction system for chemotaxis to form a core signaling complex couples CheA activity to chemoreceptor control: two CheW coupling protein molecules span a histidine kinase CheA dimer and two chemoreceptors (also known as methyl-accepting chemotaxis protein, MCP) trimers of dimers which further transfer the signal to the flagellar motor through CheY. The current review summarizes and highlights the molecular mechanism involved in bacterial chemotaxis, its physiological benefits such as locating suitable nutrients and niches for bacterial growth, and various assay techniques used for the detection of chemotactic motility.
细菌的一个普遍特性是它们能够向更适宜的环境移动，这也有助于诸如定殖等与宿主相关的活动，并为细胞带来多种益处，比如细菌朝着有利梯度移动或远离有害梯度，这被称为趋化性。细菌通过顺时针和逆时针旋转鞭毛来实现这一点，从而导致“游动”和“翻滚”。细菌感知并响应环境因素（如pH、渗透压、氧化还原电位和温度）的任何类型变化的这种能力，是一种依赖于偶联蛋白的标准信号转导系统，即细菌趋化性系统。趋化性系统中偶联蛋白有两种结构：CheW和CheV。通常，趋化性的信号转导系统形成一个核心信号复合物，将CheA活性与化学感受器控制偶联起来：两个CheW偶联蛋白分子跨越一个组氨酸激酶CheA二聚体和两个化学感受器（也称为甲基接受趋化蛋白，MCP）二聚体三聚体，后者再通过CheY将信号传递给鞭毛马达。本综述总结并强调了细菌趋化性所涉及的分子机制、其生理益处（如为细菌生长定位合适的营养物质和生态位）以及用于检测趋化运动性的各种测定技术。
