Download MendeleyStructural basis for recognition of frizzled proteins byClostridium difficiletoxin B.
Chen, P., Tao, L., Wang, T., Zhang, J., He, A., Lam, K.H., Liu, Z., He, X., Perry, K., Dong, M., Jin, R.(2018) Science 360: 664-669
- PubMed: 29748286
- DOI: https://doi.org/10.1126/science.aar1999
- Primary Citation of Related Structures:
6C0B - PubMed Abstract:
Clostridium difficile infection is the most common cause of antibiotic-associated diarrhea in developed countries. The major virulence factor, C. difficile toxin B (TcdB), targets colonic epithelia by binding to the frizzled (FZD) family of Wnt receptors, but how TcdB recognizes FZDs is unclear. Here, we present the crystal structure of a TcdB fragment in complex with the cysteine-rich domain of human FZD2 at 2.5-angstrom resolution, which reveals an endogenous FZD-bound fatty acid acting as a co-receptor for TcdB binding. This lipid occupies the binding site for Wnt-adducted palmitoleic acid in FZDs. TcdB binding locks the lipid in place, preventing Wnt from engaging FZDs and signaling. Our findings establish a central role of fatty acids in FZD-mediated TcdB pathogenesis and suggest strategies to modulate Wnt signaling.
Organizational Affiliation:
Department of Physiology and Biophysics, University of California, Irvine, Irvine, CA, USA.
