Processive dynamics of the usher assembly platform during uropathogenic Escherichia coli P pilus biogenesis.
Du, M., Yuan, Z., Werneburg, G.T., Henderson, N.S., Chauhan, H., Kovach, A., Zhao, G., Johl, J., Li, H., Thanassi, D.G.(2021) Nat Commun 12: 5207-5207
- PubMed: 34471127 
- DOI: https://doi.org/10.1038/s41467-021-25522-6
- Primary Citation of Related Structures:  
7LHG, 7LHH, 7LHI - PubMed Abstract: 
Uropathogenic Escherichia coli assemble surface structures termed pili or fimbriae to initiate infection of the urinary tract. P pili facilitate bacterial colonization of the kidney and pyelonephritis. P pili are assembled through the conserved chaperone-usher pathway. Much of the structural and functional understanding of the chaperone-usher pathway has been gained through investigations of type 1 pili, which promote binding to the bladder and cystitis. In contrast, the structural basis for P pilus biogenesis at the usher has remained elusive. This is in part due to the flexible and variable-length P pilus tip fiber, creating structural heterogeneity, and difficulties isolating stable P pilus assembly intermediates. Here, we circumvent these hindrances and determine cryo-electron microscopy structures of the activated PapC usher in the process of secreting two- and three-subunit P pilus assembly intermediates, revealing processive steps in P pilus biogenesis and capturing new conformational dynamics of the usher assembly machine.
Organizational Affiliation: 
Department of Structural Biology, Van Andel Institute, Grand Rapids, MI, USA.