Reconstitution of a minimal machinery capable of assembling periplasmic type IV pili

Proc Natl Acad Sci U S A. 2017 Jun 20;114(25):E4978-E4986. doi: 10.1073/pnas.1618539114. Epub 2017 Jun 6.


Type IV pili (Tfp), which are key virulence factors in many bacterial pathogens, define a large group of multipurpose filamentous nanomachines widespread in Bacteria and Archaea. Tfp biogenesis is a complex multistep process, which relies on macromolecular assemblies composed of 15 conserved proteins in model gram-negative species. To improve our limited understanding of the molecular mechanisms of filament assembly, we have used a synthetic biology approach to reconstitute, in a nonnative heterologous host, a minimal machinery capable of building Tfp. Here we show that eight synthetic genes are sufficient to promote filament assembly and that the corresponding proteins form a macromolecular complex at the cytoplasmic membrane, which we have purified and characterized biochemically. Our results contribute to a better mechanistic understanding of the assembly of remarkable dynamic filaments nearly ubiquitous in prokaryotes.

Keywords: filament assembly; synthetic biology; type IV filamentous nanomachines; type IV pili.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Archaea / metabolism
  • Bacteria / metabolism
  • Bacterial Proteins / metabolism
  • Cell Membrane / metabolism
  • Fimbriae Proteins / metabolism*
  • Fimbriae, Bacterial / metabolism*
  • Periplasm / metabolism*
  • Prokaryotic Cells / metabolism
  • Virulence Factors / metabolism


  • Bacterial Proteins
  • Virulence Factors
  • Fimbriae Proteins