Biofilm formation by Vibrio cholerae facilitates environmental persistence, and hyperinfectivity within the host. Biofilm formation is regulated by 3’,5’-cyclic diguanylate (c-di-GMP) and requires production of the type IV mannose-sensitive hemagglutinin (MSHA) pilus. Here, we show that the MSHA pilus is a dynamic extendable and retractable system, and its activity is directly controlled by c-di-GMP. The interaction between c-di-GMP and the ATPase MshE promotes pilus extension, whereas low levels of c-di-GMP correlate with enhanced retraction. Loss of retraction facilitated by the ATPase PilT increases near-surface roaming motility, and impairs initial surface attachment. However, prolonged retraction upon surface attachment results in reduced MSHA-mediated surface anchoring and increased levels of detachment. Our results indicate that c-di-GMP directly controls MshE activity, thus regulating MSHA pilus extension and retraction dynamics, and modulating V. cholerae surface attachment and colonization.

霍乱弧菌形成的生物膜促进环境持久性和宿主体内的过度感染性。生物膜的形成受 3',5'-环二鸟苷酸 (c-di-GMP) 调节，并需要产生 IV 型甘露糖敏感血凝素 (MSHA) 菌毛。在这里，我们证明 MSHA 菌毛是一个动态可伸缩系统，其活性直接受 c-di-GMP 控制。 c-di-GMP 和 ATPase MshE 之间的相互作用促进菌毛伸展，而低水平的 c-di-GMP 与增强的回缩相关。 ATPase PilT 促进的回缩丧失增加了近表面漫游运动，并损害了初始表面附着。然而，表面附着时的长时间回缩会导致 MSHA 介导的表面锚定减少和脱离水平增加。我们的结果表明，c-di-GMP 直接控制 MshE 活性，从而调节 MSHA 菌毛伸展和收缩动力学，并调节霍乱弧菌表面附着和定植。