地杆菌中基因Gmet_1513对其产电及生物膜形成的影响  

Effect of the gene Gmet_1513 on electrogenesis and biofilm formation of Geobacter

作　　者：杨钰婷 靖宪月 陈姗姗 刘星 周顺桂 YANG Yuting;JING Xianyue;CHEN Shanshan;LIU Xing;ZHOU Shungui(Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation,College of Resources and Environment,Fujian Agriculture and Forestry University,Fuzhou 350002;Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds,School of Ecology,Environmental and Resources,Guangdong University of Technology,Guangzhou 510006;Key Laboratory of Agricultural Environment in Universities of Shandong,College of Resources and Environment,Shandong Agricultural University,Taian 271018;Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory),Jieyang 515200)

机构地区：[1]福建农林大学资源与环境学院,福建省土壤环境健康与调控重点实验室,福州350002 [2]广东工业大学生态环境与资源学院,广东省流域水环境治理与水生态修复重点实验室,广州510006 [3]山东农业大学资源与环境学院,山东省高校农业环境重点实验室,泰安271018 [4]化学与精细化工广东省实验室揭阳分中心,揭阳515200

出　　处：《环境科学学报》2023年第7期121-129,共9页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.41877052)。

摘　　要：Geobacter metallireducens GS-15中存在Gmet_1513基因可编码具有自动诱导结合域的LuxR家族转录调控因子,使GS-15借助N-酰基高丝氨酸内酯促进产电及生物膜形成成为可能.而目前有关地杆菌群感效应的相关研究大多基于投加化学信号分子或信号分子淬灭剂的手段,缺乏靶向性与精确性.本研究构建了Geobacter metallireducens GS-15的Gmet_1513基因缺失突变株(Δgmet_1513),研究Gmet_1513在GS-15菌株发挥电活性过程中的功能.实验结果表明,Δgmet_1513与野生型菌株相比产生群感效应信号分子的能力减弱,Δgmet_1513外膜蛋白种类减少,生物电化学系统的启动时间延长且电流输出减弱.与此同时,激光共聚焦图像对比结果表明Δgmet_1513无法形成成熟致密电活性生物膜,EPS成分显示Δgmet_1513的蛋白质含量低,多糖、脂质含量高,使其电子产量低且转移困难,无法进行AHLs的识别及结合导致电子传递相关蛋白无法表达,电子传递多重受阻.本研究为今后以Gmet_1513基因为靶标,利用群感效应相关蛋白表达调控地杆菌生物膜形成以及产电提供依据.Gmet_1513 gene,which can encode transcriptional regulator of LuxR family with an autoinducer-binding domain in Geobacter metallireducens GS-15,makes it possible for GS-15 to to promote electricity generation and biofilm formation with N-acylhomoserine lactone.Most of the recent studies on the quorum sensing effect of Geobacter metallireducens are based on the addition of chemical signal molecules or signal molecule quenchers,which lack targeting and precision.In this study,a Gmet_1513 gene mutant strain(Δgmet_1513)of Geobacter metallireducens GS-15 was constructed to investigate the function of Gmet_1513 gene during the electrogenesis of GS-15 strain.The experimental results showed thatΔgmet_1513 produced fewer chemical signal molecules compared with the wild-type strain,and outer membrane proteins ofΔgmet_1513 had a reduced variety,which led to a delayed initiation time and reduced current output of the bioelectrochemical system.The confocal laser scanning microscope images showed thatΔgmet_1513 could not form mature and dense electroactive biofilm.EPS component analysis revealed thatΔgmet_1513 had lower protein content and higher polysaccharide and lipid content than wild-type strain,which caused low electron production and difficult electron transport.TheΔgmet_1513 could not recognize and combine with AHLs,resulting in the down-expression of electron transport-related proteins And multiple barriers for electron transport inΔgmet_1513.This study provides a basis for future studies about regulating biofilm formation and electrogenesis of Geobacter via targeting the Gmet_1513 gene to change the quorum sensing protein expression.

关 键 词：革兰氏阴性菌 Gmet_1513基因 高丝氨酸内酯 电化学活性 

分 类 号：X172[环境科学与工程—环境科学]