Structural mechanisms of Tad pilus assembly and its interaction with an RNA virus. uri icon

abstract

  • Caulobacter crescentus Tad (tight adherence) pili, part of the type IV pili family, are crucial for mechanosensing, surface adherence, bacteriophage (phage) adsorption, and cell-cycle regulation. Unlike other type IV pilins, Tad pilins lack the typical globular sheet domain responsible for pilus assembly and phage binding. The mechanisms of Tad pilus assembly and its interaction with phage Cb5 have been elusive. Using cryo-electron microscopy, we unveiled the Tad pilus assembly mechanism, featuring a unique network of hydrogen bonds at its core. We then identified the Tad pilus binding to the Cb5 maturation protein (Mat) through its region. Notably, the amino terminus of Cb5 Mat is exposed outside the capsid and phage/pilus interface, enabling the attachment of fluorescent and affinity tags. These engineered Cb5 virions can be efficiently assembled and purified in Escherichia coli, maintaining infectivity against C. crescentus, which presents promising applications, including RNA delivery and phage display.

published proceedings

  • Sci Adv

author list (cited authors)

  • Wang, Y., Theodore, M., Xing, Z., Narsaria, U., Yu, Z., Zeng, L., & Zhang, J.

complete list of authors

  • Wang, Yuhang||Theodore, Matthew||Xing, Zhongliang||Narsaria, Utkarsh||Yu, Zihao||Zeng, Lanying||Zhang, Junjie

publication date

  • May 2024