School of Environmental Science and Engineering, Shandong University, Jinan, Shandong Province 250100, China.
College of Geography and Environment, Shandong Normal University, 88# East Wenhua Road, Jinan, Shandong 250014, China.
Chem Biol Interact. 2018 Aug 25;292:30-36. doi: 10.1016/j.cbi.2018.06.025. Epub 2018 Jun 21.
More and more composite nano-photocatalysts were developed by doping, modifying and coupling, which expanded its application but resulted in pollution due to the unrecyclability. Composite photocatalyst TiO/WO/GO, as a model, was evaluated by exploring the molecular mechanism of TiO/WO/GO-induced activity changes of catalase (CAT) and superoxide dismutase (SOD). Results showed that TiO/WO/GO could lead to conformational and functional changes of CAT and SOD. The activity of both CAT and SOD increased depending on the exposure dose of TiO/WO/GO. The change skeleton structure and increase of α-helix content of CAT and SOD were certificated with UV-vis absorption and CD measurements. Intrinsic fluorescence of CAT and SOD were quenched by dynamic quenching. Micro-environment of amino acid residues of CAT and SOD became more hydrophilic, and the microenvironment of Trp residues was more vulnerable than Tyr residues with TiO/WO/GO exposure. In addition, inhibitory comparison between GO, TiO, WO and TiO/WO/GO was made, results showed that composite nano-photocatalyst exhibited different inhibitory compared to their parent nano-particles.
越来越多的复合纳米光催化剂通过掺杂、修饰和耦合得到了开发，这扩展了其应用范围，但由于不可回收性而导致了污染。以 TiO/WO/GO 复合光催化剂为例，通过探讨 TiO/WO/GO 诱导过氧化氢酶 (CAT) 和超氧化物歧化酶 (SOD) 活性变化的分子机制来评估其性能。结果表明，TiO/WO/GO 可导致 CAT 和 SOD 的构象和功能发生变化。CAT 和 SOD 的活性均随 TiO/WO/GO 暴露剂量的增加而增加。通过紫外可见吸收和圆二色性 (CD) 测量证明了 CAT 和 SOD 的骨架结构发生了变化，α-螺旋含量增加。CAT 和 SOD 的内源荧光被动态猝灭。CAT 和 SOD 氨基酸残基的微环境变得更加亲水，与 Tyr 残基相比，Trp 残基的微环境在暴露于 TiO/WO/GO 时更易受到影响。此外，还比较了 GO、TiO、WO 和 TiO/WO/GO 之间的抑制作用，结果表明，复合纳米光催化剂与它们的母体纳米粒子相比表现出不同的抑制作用。
