Zhang Chengyang, Zhang Guoyang, Jin Jiyuan, Zheng Hongcen, Zhou Zhiwei, Zhang Shujuan
State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China.
Environ Sci Technol. 2023 Apr 18;57(15):6188-6195. doi: 10.1021/acs.est.2c09682. Epub 2023 Apr 3.
The coexistence of selenite (Se(IV)) and acetylacetone (AA) generated a synergistic effect on the growth inhibition of a bloom-forming cyanobacterium, . The mechanism behind this phenomenon is of great significance in the control of harmful algal blooms. To elucidate the role of Se(IV) in this effect, the reactions in ternary solutions composed of Se(IV), AA (or two other similar hydrogen donors), and quinones, especially benzoquinone (BQ), were investigated. The transformation kinetic results demonstrate that Se(IV) played a catalytic role in the reactions between AA (or ascorbic acid) and quinones. By comparison with five other oxyanions (sulfite, sulfate, nitrite, nitrate, and phosphate) and two AA derivatives, the formation of an AA-Se(IV) complexation intermediate was confirmed as a key step in the accelerated reactions between BQ and AA. To our knowledge, this is the first report on Se(IV) as a catalyst for quinone-involved reactions. Since both quinones and Se are essential in cells and there are many other chemicals of similar electron-donating properties to that of AA, the finding here shed light on the regulation of electron transport chains in a variety of processes, especially the redox balances that are tuned by quinones and glutathione.
亚硒酸盐（Se(IV)）与乙酰丙酮（AA）共存对一种形成水华的蓝藻的生长抑制产生了协同效应。这一现象背后的机制在有害藻华的控制中具有重要意义。为了阐明Se(IV)在此效应中的作用，研究了由Se(IV)、AA（或其他两种类似的氢供体）和醌类，特别是苯醌（BQ）组成的三元溶液中的反应。转化动力学结果表明，Se(IV)在AA（或抗坏血酸）与醌类的反应中起催化作用。通过与其他五种含氧阴离子（亚硫酸盐、硫酸盐、亚硝酸盐、硝酸盐和磷酸盐）以及两种AA衍生物进行比较，证实AA-Se(IV)络合中间体的形成是BQ与AA加速反应中的关键步骤。据我们所知，这是关于Se(IV)作为醌参与反应的催化剂的首次报道。由于醌类和硒在细胞中都是必不可少的，并且存在许多其他与AA具有相似供电子性质的化学物质，因此这里的发现为各种过程中电子传递链的调节提供了线索，特别是由醌类和谷胱甘肽调节的氧化还原平衡。
