Exploring the interaction between Cry1Ac protein and Zn2+, Cd2+ metal ions by fluorescence quenching and molecular docking approaches
Exploring the interaction between Cry1Ac protein and Zn2+, Cd2+ metal ions by fluorescence quenching and molecular docking approaches
复制标题
通过荧光猝灭和分子对接方法探索Cry1Ac蛋白与Zn2 , Cd2金属离子的相互作用
DOI：
10.1016/j.chemosphere.2022.134105
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发表时间：
2022
期刊：
影响因子：
8.8
通讯作者：
Ai ping Wu
中科院分区：
文献类型：
--
作者：
Li Wang;Yunshan Liang;Zhibin Wu;Yufeng Liu;Yun-hua Xiao;Teng Hu;Rong Gao;Jun Fang;Jiao Liu;Ai ping Wu
苏云金芽孢杆菌(Bt)蛋白与金属离子有很强的络合能力，这可能会增加金属离子在土壤多介质体系中的迁移。本研究通过光谱分析和分子对接方法研究了Cry1Ac蛋白与金属离子(锌、镉)的相互作用。光谱结果表明，Zn2+和Cd2+对Cry1Ac蛋白的荧光强度均有静态猝灭作用。4-5个数量级的结合常数也表明了离子与Cry1Ac蛋白之间的相互作用。热力学分析表明，氢键和范德华力在整个过程中起主导作用。根据Förster非辐射能量转移理论，金属离子与Cry1Ac蛋白的结合距离约为0.21-0.24 nm，表明它们之间存在非辐射能量转移。此外，分子对接显示，金属离子参与了与Cry1Ac在Asp569、Thr560、Asn564和Gln566位置的配体结合。本工作为我们进一步了解Cry1Ac对重金属迁移的影响提供了合理的模型。这些结果可以从机理上深入了解金属离子-Cry1Ac相互作用的本质，并为金属离子-Cry1Ac结合的毒性风险提供重要信息。·研究了锌/镉与Cry1Ac蛋白的相互作用。·Zn2+/Cd2+通过静态猝灭的方法猝灭Cry1Ac的荧光。·锌离子与Cry1Ac蛋白的结合比镉离子强。·结合过程主要由氢键和范德华力驱动。·通过分子对接，确定了金属离子与Cry1Ac的准确结合部位。
Bacillus Thuringiensis (Bt) protein has a strong ability to complex with metal ions, which may increase the transport of metal ions in the soil multi-media system. In this study, the interactions between Cry1Ac protein and metal ions (Zn 2+ and Cd 2+ ) were investigated through spectroscopies and molecular docking methods. The spectra results showed that both Zn 2+ and Cd 2+ quenched the fluorescence intensity of Cry1Ac protein through the static quenching. The binding constants with 4–5 orders of magnitude also indicated the interactions between the ions and the Cry1Ac protein. The thermodynamic analysis showed that hydrogen bonds and van der Waals forces were predominant during the processes. In terms of the Förster non-radiation energy transfer theory, the binding distances between metal ions and Cry1Ac protein were approximately 0.21–0.24 nm, indicating the existence of a non-radiative energy transfer between them. Furthermore, molecular docking revealed that the metal ions participated in ligand binding with the Cry1Ac at the locations Asp569, Thr560, Asn564 and Gln566. The present work provided reasonable models helping us further understand the transport effect of heavy metals in the presence of Cry1Ac. The results could provide mechanistic insights into the nature of metal ions-Cry1Ac interactions and offer important information on the toxicity risk of metal ions-Cry1Ac binding interactions. • The interaction of Zn 2+ /Cd 2+ with Cry1Ac protein was studied. • Zn 2+ /Cd 2+ quenched the fluorescence of Cry1Ac by static quenching. • Binding of Zn 2+ to Cry1Ac protein was stronger than that of Cd 2+ . • The binding processes were mainly driven by hydrogen bonds and van der Waals forces. • The exactly binding sites of Zn 2+ /Cd 2+ metal ions with Cry1Ac were identified by molecular docking.