铜绿微囊藻对水体微塑料胁迫的响应研究

Study on the Response of Microcystis aeruginosa to Microplastic Stress in Water

为揭示微塑料(microplastics,MPs)对有害藻类的胁迫机理,以富营养化水体中的典型蓝藻--铜绿微囊藻(Microcystis aeruginosa)为研究对象,探究其对不同粒径和质量浓度的聚对苯二甲酸乙二醇酯(polyethylene glycol terephthalate,PET)胁迫的响应.结果表明,PET未破损藻细胞,但会影响藻细胞生长及藻毒素的合成与释放.在10μm的PET胁迫下,藻细胞生长随PET质量浓度增大而受到更为显著的抑制作用;在相同粒径的PET(100 mg/L)胁迫下,其生长抑制可能受光合作用相关基因相对表达量下调的调控.此外,在100 mg/L PET胁迫下,胞内藻毒素含量下降,可能与微藻生长受到抑制及藻毒素相关基因mcyA相对表达量下调有关.

In order to reveal the stress mechanism of microplastics(MPs)on harmful algae,Microcystis aeruginosa,a typical cyanobacteria in eutrophic water,was taken as the research object to explore its response under the stress of polyethylene glycol terephthalate(PET)with different particle sizes and concentrations.The results showed that PET did not damage algal cells,but affected their growth and the synthesis and release of microcystins.Under PET stress of 10μm,the growth of algal cells was significantly inhibited with the increase of PET concentration.Under the same particle size PET(100 mg/L)stress,its growth inhibition may be regulated by the down-regulation of the relative expression of photosynthesis-related genes.In addition,under 100 mg/L PET stress,intracellular microcystins decreased,which may be related to the inhibition of microalgae growth and the down-regulation of the relative expression of microcystins-related gene mcyA.