Yang Meng, Du Daolin, Zhu Fang, Wang Xiangrong
School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, China.
Department of Environmental Science and Engineering, Fudan University, Shanghai, 200438, China.
Environ Pollut. 2024 Feb 1;342:123022. doi: 10.1016/j.envpol.2023.123022. Epub 2023 Nov 25.
Harmful cyanobacterial blooms have been a global environmental problem. Discharge of anthropogenic pollutants and excess nutrient import into the freshwater bodies may be the biggest drivers of bloom. Bisphenol A (BPA), a typical endocrine-disrupting compound, is frequently detected in different natural waters, which was a threat to the balance of aquatic ecosystem. Yet mechanistic understanding of the bloom and microcystin generation under combined pollution conditions is still a mystery. Herein, the cellular and metabolomic responses to BPA exposure and phosphorus (P) levels in Microcystis aeruginosa were investigated throughout its growth period. The results showed that the stress response of M. aeruginosa to BPA was characterized by a decrease in growth density, an increase in P utilization, an increase in ATPase activity, a disruption of the photosynthetic system, and an increase in the production and release of microcystins (MCs). However, these effects are highly dependent on the growth stage of the cyanobacterial cell and the magnitude of the added P concentration. In addition, exposure to a high concentration (10 μM) of BPA significantly stimulated the production of 20.7% more and the release of 29.2% more MCs from M. aeruginosa cells at a low P level. The responses of reactive oxygen species (ROS), superoxide dismutase (SOD) and malondialdehyde (MDA) suggested that exposure to BPA exposure at a low P level can lead to oxidative stress in M. aeruginosa. In addition, the differentially expressed 63 metabolites showed that cell growth, energy generation and photosynthesis were mainly regulated by the metabolic network of 3-phosphoglyceric acid (3-PGA), D-glucose 6-phosphate, UDP-α-D-galactose and UDP-N-acetyl-D-galactosamine (UDP-GalNAc) metabolism. Amino acids and lipid metabolism collectively mediated MCs production and release. These findings will provide important references for the control of harmful cyanobacterial blooms under combined pollution.
有害蓝藻水华已成为一个全球性的环境问题。人为污染物的排放以及过量营养物质流入淡水水体可能是水华爆发的最大驱动因素。双酚A（BPA）是一种典型的内分泌干扰化合物，在不同天然水体中经常被检测到，这对水生生态系统的平衡构成了威胁。然而，在复合污染条件下水华爆发和微囊藻毒素产生的机制仍不清楚。在此，研究了铜绿微囊藻在整个生长周期中对BPA暴露和磷（P）水平的细胞及代谢组学响应。结果表明，铜绿微囊藻对BPA的应激反应表现为生长密度降低、P利用率增加、ATP酶活性增加、光合系统破坏以及微囊藻毒素（MCs）的产生和释放增加。然而，这些影响高度依赖于蓝藻细胞的生长阶段和添加P浓度的大小。此外，在低P水平下，暴露于高浓度（10 μM）的BPA显著刺激铜绿微囊藻细胞产生的MCs增加20.7%，释放量增加29.2%。活性氧（ROS）、超氧化物歧化酶（SOD）和丙二醛（MDA）的响应表明，在低P水平下暴露于BPA会导致铜绿微囊藻产生氧化应激。此外，63种差异表达的代谢物表明，细胞生长、能量产生和光合作用主要受3-磷酸甘油酸（3-PGA）、6-磷酸-D-葡萄糖、UDP-α-D-半乳糖和UDP-N-乙酰-D-半乳糖胺（UDP-GalNAc）代谢的代谢网络调控。氨基酸和脂质代谢共同介导了MCs的产生和释放。这些发现将为复合污染条件下有害蓝藻水华的控制提供重要参考。
