Deciphering the toxicity of bisphenol a to Candida rugosa lipase through spectrophotometric methods.
Deciphering the toxicity of bisphenol a to Candida rugosa lipase through spectrophotometric methods.
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DOI：
10.1016/j.jphotobiol.2016.08.011
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发表时间：
2016-10
期刊：
影响因子：
--
通讯作者：
Rui Zhang;Lining Zhao;Rutao Liu
中科院分区：
文献类型：
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作者：
Rui Zhang;Lining Zhao;Rutao Liu
双酚A广泛用于食品包装和饮料容器的制造，会侵入我们的食物并造成污染。假丝酵母脂肪酶是一种用于生物催化和生物转化的多功能酶，可生产用于食品、药品和香料的有用材料。通过紫外可见分光光度计、稳态荧光、圆二色性、同步荧光、光散射光谱、分子对接和酶活性测定等方法研究双酚A与假丝酵母脂肪酶的体外相互作用，以更好地了解双酚A的毒性和毒性机制。利用色氨酸氨基酸残基的固有荧光和球状蛋白假丝酵母脂肪酶的二级结构，深入研究双酚A引起的结构变化。荧光表明双酚A与假丝酵母多糖脂肪酶相互作用，使色氨酸暴露于疏水环境。多重光谱测试表明，双酚A的添加增强了念珠菌脂肪酶的内源荧光，疏松了其骨架结构，改变了其二级结构。而且，假丝酵母脂肪酶活性的增加表明假丝酵母脂肪酶催化三联体的位置或结构可能发生改变。分子对接结果表明，双酚A与丝氨酸209残基结合，这可能是念珠菌脂肪酶活性增加的另一个原因。此外，从共振光散射和动态光散射的结果可以看出，念珠菌脂肪酶的体积减少并且盖子可能被剥离。
Bisphenol A is widely used in the manufacture of food packaging and beverage containers and can invade our food and cause contamination. Candida rugose lipase has been a versatile enzyme for biocatalysis and biotransformations to produce useful materials for food, pharmaceutical and flavor. The interactions between bisphenol A and Candida rugosa lipase in vitro were studied by UV–vis, steady-state fluorescence, circular dichroism, synchronous fluorescence, light scattering spectra, molecular docking and enzyme activity assay to better understand the toxicity and toxic mechanisms of bisphenol A. The intrinsic fluorescence of the tryptophan amino acid residue and the secondary structure of the globular protein candida rugose lipase were made use of to thoroughly investigate the structural changes caused by bisphenol A. The results of the fluorescence indicated that bisphenol A interacted with candida rugose lipase and made tryptophan be exposed to a hydrophobic environment. Multi-spectroscopic measurements showed that the addition of bisphenol A increased the intrinsic fluorescence ofCandida rugosalipase, loosened its skeleton structure and changed its secondary structure. Also, the increased activity ofCandida rugosalipase revealed that the position or the structure of the catalytic triad ofCandida rugosalipase may be changed. The molecular docking results showed that bisphenol A bound with the residue Serine 209 which could be another reason for the increased activity ofCandida rugosalipase. Moreover, as can be seen from the results of resonance light scattering and dynamic light scattering, the volume of theCandida rugosalipase was decreased and the lid may be stripped.