The opportunistic pathogen Pseudomonas aeruginosa explores surfaces using twitching motility powered by retractile extracellular filaments called type IV pili (T4P). Single cells twitch by sequential T4P extension, attachment, and retraction. How single cells coordinate T4P to efficiently navigate surfaces remains unclear. We demonstrate that P. aeruginosa actively directs twitching in the direction of mechanical input from T4P in a process called mechanotaxis. The Chp chemotaxis-like system controls the balance of forward and reverse twitching migration of single cells in response to the mechanical signal. Collisions between twitching cells stimulate reversals, but Chp mutants either always or never reverse. As a result, while wild-type cells colonize surfaces uniformly, collision-blind Chp mutants jam, demonstrating a function for mechanosensing in regulating group behavior. On surfaces, Chp senses T4P attachment at one pole, thereby sensing a spatially resolved signal. As a result, the Chp response regulators PilG and PilH control the polarization of the extension motor PilB. PilG stimulates polarization favoring forward migration, while PilH inhibits polarization, inducing reversal. Subcellular segregation of PilG and PilH efficiently orchestrates their antagonistic functions, ultimately enabling rapid reversals upon perturbations. The distinct localization of response regulators establishes a signaling landscape known as local excitation–global inhibition in higher-order organisms, identifying a conserved strategy to transduce spatially resolved signals.

机会性病原体铜绿假单胞菌使用由称为 IV 型菌毛 (T4P) 的可伸缩细胞外细丝驱动的抽搐运动探索表面。单个细胞通过连续的 T4P 延伸、附着和收缩而抽搐。单个细胞如何协调 T4P 以有效地导航表面仍不清楚。我们证明铜绿假单胞菌在称为机械趋向性的过程中，主动引导 T4P 的机械输入方向上的抽搐。Chp 趋化性系统控制单细胞响应机械信号的正向和反向抽搐迁移的平衡。抽搐细胞之间的碰撞会刺激逆转，但 Chp 突变体要么总是逆转，要么永远不会逆转。结果，虽然野生型细胞均匀地定植于表面，但碰撞盲 Chp 突变体会​​堵塞，这表明机械感应在调节群体行为方面具有功能。在表面上，Chp 在一个极点感应 T4P 附着，从而感应到空间解析信号。因此，Chp 响应调节器 PilG 和 PilH 控制伸展电机 PilB 的极化。PilG 刺激极化有利于向前迁移，而 PilH 抑制极化，诱导逆转。PilG 和 PilH 的亚细胞分离有效地协调了它们的拮抗功能，最终能够在扰动时快速逆转。响应调节器的独特定位在高阶生物中建立了称为局部激发 - 全局抑制的信号景观，确定了一种转换空间解析信号的保守策略。