C-di-GMP modulates type IV MSHA pilus retraction and surface attachment in Vibrio cholerae

Kyle A Floyd,Calvin K Lee,Daniel C Wu,Jin Hwan Park,Hannah Q Hughes,Ali M Farhat,Benjamin Crair,Yves V Brun,Wujing Xian,Mahmoud Nametalla,Javier Campos-Gómez ,Jennifer L Chlebek,Courtney K Ellison,Gerard C L Wong,Jun Li ,S J Zhu ,Nicolas Biais,Charles J Lomba,Ankur B Dalia,Aneesa Valentine,Fitnat H Yildiz

doi:10.1038/s41467-020-15331-8

Abstract

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.

Highlights

Biofilm formation by Vibrio cholerae facilitates environmental persistence, and hyperinfectivity within the host
These results indicate that c-di-GMP-mediated mannose-sensitive hemagglutinin (MSHA) pilus extension/retraction activity is facilitated via the regulation of MshE function, and suggest that this multifaceted orchestration of pilus dynamics is vital for V. cholerae surface attachment and biofilm formation
Deciphering the mechanism(s) underlying initial surface attachment is fundamental for understanding the switch from planktonic to sessile lifestyles

Summary

Introduction

Biofilm formation by Vibrio cholerae facilitates environmental persistence, and hyperinfectivity within the host. Our results indicate that c-di-GMP directly controls MshE activity, regulating MSHA pilus extension and retraction dynamics, and modulating V. cholerae surface attachment and colonization. Despite the vital role and importance of the MSHA pilus in V. cholerae surface attachment, the dynamics of MSHA extension and retraction and their consequence on biofilm formation remain to be elucidated. Our initial studies suggested that c-di-GMP interacts with MshE to promote MSHA production, and facilitate the transition of V. cholerae from motile to surface-attached cells through modulation of near-surface motility and attachment[18]. We observe that alteration of MSHA activity dictates the ability of V. cholerae to persist within a model of biofilm competition Taken together, these results indicate that c-di-GMP-mediated MSHA pilus extension/retraction activity is facilitated via the regulation of MshE function, and suggest that this multifaceted orchestration of pilus dynamics is vital for V. cholerae surface attachment and biofilm formation

Methods

Results

Conclusion