重金属和Bt蛋白联合暴露对细菌毒性的影响  

Effects of combined exposure to heavy metals and Bt protein on bacterial toxicity

作　　者：高帆帆 王莉 杨思培 高榕 吴志斌 方俊 梁运姗[1,2] GAO Fanfan;WANG Li;YANG Sipei;GAO Rong;WU Zhibin;FANG Jun;LIANG Yunshan(College of Resources and Environment,Hunan Agricultural University,Hunan Provincial Key Laboratory of Rural Ecosystem Health in Dongting Lake Area,Changsha 410128,China;College of Bioscience and Biotechnology,Hunan Agricultural University,Hunan Engineering Laboratory for Pollution Control and Waste Utilization in Swine Production,Changsha 410128,China)

机构地区：[1]湖南农业大学资源环境学院,洞庭湖区农村生态系统健康湖南省重点实验室,长沙410128 [2]湖南农业大学生物科学技术学院,湖南省猪场废弃物无害化处理与资源化利用工程研究中心,长沙410128

出　　处：《农业环境科学学报》2023年第7期1487-1494,共8页Journal of Agro-Environment Science

基　　金：国家自然科学基金项目(41877491);湖南省自然科学基金项目(2022JJ30307);湖南农业大学“1515”人才项目。

摘　　要：为考察重金属和Bt蛋白联合暴露对微生物生物毒性的影响,本研究选用Zn^(2+)、Cd^(2+)作为重金属离子代表,Cry1Ac蛋白作为Bt蛋白代表,通过分析不同条件下大肠杆菌(Escherichia coli)和枯草芽孢杆菌(Bacillus subtilis)的生长曲线、菌落数、活性氧(ROS)产生量,探究Zn^(2+)、Cd^(2+)、Cry1Ac蛋白单独和联合暴露对细菌生长及毒性的影响,同时选用费氏弧菌(Vibrio fischeri)进行急性毒性试验。结果表明:Zn^(2+)、Cd^(2+)及Cry1Ac蛋白浓度增加(Zn^(2+)为2~20μg∙mL^(-1),Cd^(2+)为2~10μg∙mL^(-1),Cry1Ac为0.2~4μg∙mL^(-1))对E.coli、B.subtilis生长产生抑制作用,细菌存活率也显著降低(P<0.05),其中B.subtilis的耐性强于E.coli;细菌ROS产生量表明,单独Zn^(2+)、Cd^(2+)能对细菌造成严重氧化损伤,而Zn^(2+)、Cd^(2+)与Cry1Ac蛋白结合能显著降低(P<0.05)金属对E.coli和B.subtilis的氧化损伤,结合后Zn^(2+)-Cry1Ac对大肠杆菌毒性效果强于Cd^(2+)-Cry1Ac;发光细菌试验结果进一步表明Cry1Ac蛋白能缓解Zn^(2+)、Cd^(2+)对细菌的毒害。研究表明重金属和Bt蛋白联合暴露时Bt蛋白能缓解重金属对细菌的毒性。To investigate the effects of combined heavy metal and Bt protein exposure on the biotoxicity of soil microorganisms,Zn^(2+)and Cd^(2+)were used as representative heavy metal ions,and Cry1Ac protein was used as the representative Bt protein in this study.In this case,the growth curve,colony number,and reactive oxygen(ROS)production of Escherichia coli and Bacillus subtilis under different conditions were analyzed to explore the effects of Zn^(2+),Cd^(2+),and Cry1Ac protein exposure on bacterial growth and toxicity.In addition,Vibrio fischeri was selected for the acute toxicity test.E.coli and B.subtilis growth was inhibited with the increase in Zn^(2+),Cd^(2+),and Cry1Ac protein concentrations(Zn^(2+):2-20μg∙mL^(-1),Cd^(2+):2-10μg∙mL^(-1),Cry1Ac:0.2-4μg∙mL^(-1)),B.subtilis tolerance was stronger than that of E.coli,and the bacterial survival rate decreased significantly(P<0.05).Bacterial ROS production indicated that the combination of Zn^(2+)and Cd^(2+)with Cry1Ac protein significantly(P<0.05)reduced the toxicity to E.coli and B.subtiliis,and the toxicity of Zn^(2+)-Cry1Ac to E.coli was stronger than that of Cd^(2+)-Cry1Ac.The luminescent bacteria test results further indicated that the Cry1Ac protein could alleviate heavy metal toxicity to bacteria.This study shows that Bt protein can alleviate the toxicity of heavy metals to bacteria when exposed to Bt protein.

关 键 词：重金属 BT蛋白 联合暴露 细菌生长 急性毒性 

分 类 号：X172[环境科学与工程—环境科学]