Skip to main content
Open Access Publications from the University of California

UC Santa Barbara

UC Santa Barbara Previously Published Works bannerUC Santa Barbara

Co-Folding of a FliF-FliG Split Domain Forms the Basis of the MS:C Ring Interface within the Bacterial Flagellar Motor.

  • Author(s): Lynch, Michael J;
  • Levenson, Robert;
  • Kim, Eun A;
  • Sircar, Ria;
  • Blair, David F;
  • Dahlquist, Frederick W;
  • Crane, Brian R
  • et al.

The interface between the membrane (MS) and cytoplasmic (C) rings of the bacterial flagellar motor couples torque generation to rotation within the membrane. The structure of the C-terminal helices of the integral membrane protein FliF (FliFC) bound to the N terminal domain of the switch complex protein FliG (FliGN) reveals that FliGN folds around FliFC to produce a topology that closely resembles both the middle and C-terminal domains of FliG. The interface is consistent with solution-state nuclear magnetic resonance, small-angle X-ray scattering, in vivo interaction studies, and cellular motility assays. Co-folding with FliFC induces substantial conformational changes in FliGN and suggests that FliF and FliG have the same stoichiometry within the rotor. Modeling the FliFC:FliGN complex into cryo-electron microscopy rotor density updates the architecture of the middle and upper switch complex and shows how domain shuffling of a conserved interaction module anchors the cytoplasmic rotor to the membrane.

Many UC-authored scholarly publications are freely available on this site because of the UC's open access policies. Let us know how this access is important for you.

Main Content
For improved accessibility of PDF content, download the file to your device.
Current View