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Updated: Jul 22, 2025
High-resolution Single Particle Analysis from Electron Cryo-microscopy Images Using SPHIRE
Published on: May 16, 2017
Cry11Aa and Cyt1Aa exhibit different structural orders in crystal topography
Shu-Wen W Chen1,2, Jean-Marie Teulon1, Jean-Luc Pellequer1
1Univ. Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale (IBS), Grenoble, France.
Abstract:
Cry11Aa and Cyt1Aa are two pesticidal toxins produced by Bacillus thuringiensis subsp. israelensis. To improve our understanding of the nature of their oligomers in the toxic actions and synergistic effects, we performed the atomic force microscopy to probe the surfaces of their natively grown crystals, and used the L-weight filter to enhance the structural features. By L-weight filtering, molecular sizes of the Cry11Aa and Cyt1Aa monomers obtained are in excellent agreement with the three-dimensional structures determined by x-ray crystallography. Moreover, our results show that the layered feature of a structural element distinguishes the topographic characteristics of Cry11Aa and Cyt1Aa crystals, suggesting that the Cry11Aa toxin has a better chance than Cyt1Aa for multimerization and therefore cooperativeness of the toxic actions.
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