The divisome is a self-enhancing machine in Escherichia coli and Caulobacter crescentus
Han Gong, Di Yan, Yuanyuan Cui, Ying Li, Jize Yang, Wenjie Yang, Rui Zhan, Qianqian Wan, Xinci Wang, Haofeng He, Xiangdong Chen, Joe Lutkenhaus, Xinxing Yang, Shishen Du
Abstract
During bacterial cytokinesis, polymers of the bacterial tubulin FtsZ coalesce into the Z ring to orchestrate divisome assembly and septal cell wall synthesis. Previous studies have found that Z ring condensation and stability is critical for successful cell division. However, how FtsZ filaments condense into a Z ring remains enigmatic and whether septal cell wall synthesis can feedback to the Z ring has not been investigated. Here, we show that FtsZ-associated proteins (Zaps) play important roles in Z ring condensation and stability, and discover septal cell wall synthesis as a novel player for Z ring condensation and stabilization in Escherichia coli and Caulobacter crescentus. Moreover, we find that the interaction between the Z ring membrane anchor, FtsA, and components of the septal cell wall synthetic complex are critical for septal cell wall synthesis-mediated Z ring condensation. Altogether, these findings suggest that the divisome is a self-enhancing machine in these two gram-negative bacteria, where the Z ring and the septal cell wall synthetic complex communicate with and reinforce each other to ensure robustness of cell division. Bacterial cytokinesis is driven by a multiprotein complex, the divisome, that is organized by the Z ring and responsible for septal cell wall synthesis. Here, Gong et al. show that septal cell wall synthesis facilitates Z-ring condensation, indicating that the divisome is a self-enhancing machine.