Crystal structure of Cry6Aa: A novel nematicidal ClyA-type alpha-pore-forming toxin from Bacillus thuringiensisHuang, J., Guan, Z., Wan, L., Zou, T., Sun, M.
(2016) Biochem Biophys Res Commun 478: 307-313
- PubMed: 27381865
- DOI: https://doi.org/10.1016/j.bbrc.2016.07.002
- Primary Citation of Related Structures:
- PubMed Abstract:
Crystal (Cry) proteins from Bacillus thuringiensis (Bt) are globally used in agriculture as proteinaceous insecticides. Numerous crystal structures have been determined, and most exhibit conserved three-dimensional architectures. Recently, we have identified a novel nematicidal mechanism by which Cry6Aa triggers cell death through a necrosis-signaling pathway via an interaction with the host protease ASP-1. However, we found little sequence conservation of Cry6Aa in our functional study. Here, we report the 1.90 angstrom (Å) resolution structure of the proteolytic form of Cry6Aa (1-396), determined by X-ray crystallography. The structure of Cry6Aa is highly similar to those of the pathogenic toxin family of ClyA-type α-pore-forming toxins (α-PFTs), which are characterized by a bipartite structure comprising a head domain and a tail domain, thus suggesting that Cry6Aa exhibits a previously undescribed nematicidal mode of action. This structure also provides a framework for the functional study of other nematicidal toxins.
College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China.