摘要
铁还原菌参与的铁循环是地表系统中物质循环的重要驱动力,自然生成和人工注入地下环境的H_(2)O_(2)可能通过氧化胁迫影响铁还原菌的活性和功能,但铁还原菌在H_(2)O_(2)扰动下的响应及机制仍不清楚.以铁还原模式菌株Shewanella oneidensis MR-1作为研究对象,结合批实验和转录组测序研究了不同浓度水平H_(2)O_(2)扰动下MR-1活性和功能的变化及其调控机制.结果表明,MR-1能够有效抵御H_(2)O_(2)的胁迫,且H_(2)O_(2)扰动使MR-1的铁还原能力增强.转录组测序表明,H_(2)O_(2)使MR-1处于抗应激状态,通过积极氧化有机物供能、促进过氧化氢酶的合成抵御H_(2)O_(2)的负面影响.
Iron cycling mediated by iron-reducing bacteria is an important factor driving material cycle in the surface system of earth.H_(2)O_(2) naturally generated and artificially injected into the subsurface environment may affect the activity and function of ironreducing bacteria through oxidative stress,but the response and mechanism of iron-reducing bacteria to H_(2)O_(2) disturbance is still unclear.In this study,Shewanella oneidensis MR-1 was chosen as a representative iron-reducing bacterium.In combination with batch experiments and RNA-seq analysis,the changes of MR-1 activity and function under different concentrations of H_(2)O_(2) and its regulatory mechanism were investigated.Results show that MR-1 could resist H_(2)O_(2) stress effectively,and H_(2)O_(2) enhanced the Fe(III)-reducing ability of MR-1.RNA-seq results show that MR-1 maintained in an anti-stress state infacing to H_(2)O_(2) disturbance,which could resist the negative effects of H_(2)O_(2) by actively oxidizing organic matter to provide energy and promoting the synthesis of catalase.
作者
赵雨溪
孙群群
童曼
袁松虎
Zhao Yuxi;Sun Qunqun;Tong Man;Yuan Songhu(State Key Laboratory of Biogeology and Environmental Geology,China University of Geosciences,Wuhan 430078,China)
出处
《地球科学》
EI
CAS
CSCD
北大核心
2023年第4期1649-1656,共8页
Earth Science
基金
国家自然科学基金项目(Nos.41703113,42025703).
关键词
铁循环
铁还原菌
氧化胁迫
地质微生物
环境地质学
iron cycling
iron-reducing bacteria
oxidative stress
geological microorganism
environmental geology