微塑料对变形杆菌生物膜生长发育的影响  

Influence of Microplastics on the Development of Proteus Biofilm

作　　者：陶辉[1,2] 戚怡婷 于多 杨兰 顾颖 厉彦辉 TAO Hui;QI Yi-ting;YU Duo;YANG Lan;GU Ying;LI Yan-hui(Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes,Ministry of Education,Hohai University,Nanjing 210098,China;College of Environment,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学浅水湖泊综合治理与资源开发教育部重点实验室,南京210098 [2]河海大学环境学院,南京210098

出　　处：《环境科学》2022年第3期1455-1462,共8页Environmental Science

基　　金：国家自然科学基金项目(52070068,52070068);苏州市科技发展计划项目(SS201846)。

摘　　要：微塑料对生物膜的影响现阶段主要集中于对成熟生物膜群落组成结构变化的研究,缺乏对不同发育阶段生物膜的研究.为探究微塑料对不同发育阶段生物膜的影响,选用环境中广泛存在的变形杆菌和1μm聚苯乙烯微塑料(PS-MPs)作为研究对象,通过暴露实验研究PS-MPs对生物膜生物量、胞外聚合物(EPS)组成和胞外酶活性的影响.结果表明,PS-MPs对不同阶段生物膜的影响存在显著差异,其抑制效应随生物膜的发育显著减轻.不同生长发育阶段的生物膜对微塑料敏感度不同.可逆附着期生物膜EPS组成、活性氧(ROS)生成和胞外酶活性的抑制效应临界浓度(NOEC)明显低于其他发育阶段,但总抗氧化能力(T-AOC)和乳酸脱氢酶(LDH)活性NOEC值与其他阶段相当.这可能是ROS介导的蛋白质氧化的结果,其他阶段生物膜较为完整的EPS可以减少但不会完全消除这种作用,说明PS-MPs对生物膜存在低毒性作用.Currently,research on the effects of microplastics(MPs)in biofilms has mainly been focused on the mature biofilm communities,with a lack of sufficient details on the influence on different development stages of biofilms.Proteus and 1μm polystyrene microplastics(PS-MPs),which are widely found in the environment,were selected as the research objects to explore the effects of microplastics on biofilms at different developmental stages.In our study,the effects of PS-MPs on biofilm biomass,extracellular polymer composition(EPS),and extracellular enzyme activity were investigated using an exposure test.Our results showed that the effect of PS-MPs on biofilms at different stages was similar,but the effect was significantly reduced with the development of biofilms.Biofilms at different development stages had different sensitivities to microplastics.In the reversible attachment stage,the no observed effect concentration(NOEC)of EPS composition,reactive oxygen species(ROS)production,and extracellular enzyme activity were significantly lower than those in other stages;however,the NOEC of total antioxidant capacity(T-AOC)and lactate dehydrogenase(LDH)activity were similar.This may be the result of ROS-mediated protein oxidation,which can be reduced but not completely eliminated by EPS in other stages of biofilm.This indicates that PS-MPs has a low toxic effect on biofilm.

关 键 词：微塑料(MPs) 变形杆菌 生物膜 发育阶段 胞外聚合物(EPS) 酶活性 

分 类 号：X172[环境科学与工程—环境科学]