Abstract：
In the intricate web of ecological relationships, pollinators such as the Italian honeybee (Apis mellifera) play a crucial role in maintaining biodiversity and agricultural productivity. This study focuses on the interactions between three neonicotinoid compounds and the honeybee\'s chemosensory protein 3 (CSP3), a key player in their olfactory system. Employing advanced spectroscopic techniques and molecular modeling, we explore the binding dynamics and conformational changes in CSP3 upon exposure to these pesticides. The research reveals that all three neonicotinoids considerably quench CSP3\'s fluorescence through a dynamic and static mixing mechanism, indicating a strong binding affinity, predominantly driven by hydrophobic interactions. UV-visible absorption, synchronous fluorescence, and 3D fluorescence spectra support slight changes in the microenvironment around the aromatic amino acids of CSP3. Circular dichroism spectra indicate a reduction in CSP3\'s α-helix content, suggesting structural alterations. Molecular docking and dynamics simulations further elucidate the binding modes and stability of these interactions, highlighting the role of specific amino acids in CSP3\'s binding cavity. Findings provide critical insights into molecular mechanisms by which neonicotinoids may impair honeybee chemosensory function, offering implications for designing safer pesticides and understanding the broader ecological impact of these chemicals on pollinator health.
摘要：
在错综复杂的生态关系网中，传粉者，例如意大利蜜蜂（Apismellifera）在维持生物多样性和农业生产力方面发挥着至关重要的作用。本研究的重点是三种新烟碱类化合物与蜜蜂的化学感觉蛋白3（CSP3）之间的相互作用，他们嗅觉系统中的关键角色。采用先进的光谱技术和分子建模，我们探索了CSP3暴露于这些农药后的结合动力学和构象变化。研究表明，所有三种新烟碱通过动态和静态混合机制显著猝灭CSP3的荧光，表明有很强的结合亲和力，主要由疏水相互作用驱动。UV-可见光吸收，同步荧光,和3D荧光光谱支持CSP3芳香族氨基酸周围的微环境略有变化。圆二色光谱表明CSP3的α-螺旋含量降低，暗示结构改变。分子对接和动力学模拟进一步阐明了这些相互作用的结合模式和稳定性，强调特定氨基酸在CSP3结合腔中的作用。研究结果为新烟碱可能损害蜜蜂化学感应功能的分子机制提供了重要见解，为设计更安全的杀虫剂和了解这些化学物质对传粉者健康的更广泛的生态影响提供了启示。
