State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, People's Republic of China.
Department of Chemistry, Chemical Biological Centre, Umeå University, 90187 Umeå, Sweden.
Environ Sci Technol. 2022 Jul 5;56(13):9683-9692. doi: 10.1021/acs.est.2c00776. Epub 2022 Jun 13.
The regulation of photosynthetic machinery with a nonoxidative approach is a powerful but challenging strategy for the selective inhibition of bloom-forming cyanobacteria. Acetylacetone (AA) was recently found to be a target-selective cyanocide for , but the cause and effect in the studied system are still unclear. By recording of the chemical fingerprints of the cells at two treatment intervals (12 and 72 h with 0.1 mM AA) with omics assays, the molecular mechanism of AA in inactivating was elucidated. The results clearly reveal the effect of AA on ferredoxin and the consequent effects on the physiological and biochemical processes of . In addition to its role as an electron acceptor of photosystem I, ferredoxin plays pivotal roles in the assimilation of nitrogen in cyanobacterial cells. The effect of AA on ferredoxin and on nonheme iron of photosystem II first cut off the photosynthetic electron transfer flow and then interrupted the synthesis of adenosine triphosphate (ATP) and reduced nicotinamide adenine dinucleotide phosphate (NADPH), which ultimately might affect carbon fixation and nitrogen assimilation metabolisms. The results here provide missing pieces in the current knowledge on the selective inhibition of cyanobacteria, which should shed light on the better control of harmful blooms.
采用非氧化方法调节光合作用机制是一种选择性抑制蓝藻水华形成的有效策略。最近发现乙酰丙酮（AA）是一种选择性的蓝藻杀灭剂，但在研究系统中其因果关系仍不清楚。通过在两个处理间隔（用 0.1mM AA 处理 12 和 72 小时）时用组学检测记录细胞的化学指纹，阐明了 AA 使失活的分子机制。结果清楚地揭示了 AA 对铁氧还蛋白的作用，以及对蓝藻细胞生理和生化过程的后续影响。除了作为光系统 I 的电子受体外，铁氧还蛋白在蓝藻细胞中氮同化过程中也起着关键作用。AA 对铁氧还蛋白和非血红素铁的光系统 II 的作用首先切断光合作用电子传递流，然后中断三磷酸腺苷（ATP）和还原型烟酰胺腺嘌呤二核苷酸磷酸（NADPH）的合成，这最终可能影响碳固定和氮同化代谢。本研究结果为选择性抑制蓝藻的现有知识提供了缺失的部分，这应该为更好地控制有害水华提供了启示。
