从单细胞水平研究电活性硫还原地杆菌Geobacter sulfurreducens的微生物腐蚀机理

微生物腐蚀在世界范围内造成严重的经济损失。通常，人们都是将生物被膜视作一个整体来进行分析其微生物腐蚀行为，因此忽略了生物被膜内部复杂的异质性，生物被膜内微生物的表观多样性以及生物被膜形成的动态过程。上述微观性质如何影响微生物腐蚀这一问题从未被深入研究过。要解答这一问题，需要从单细胞水平解析生物被膜的生长机制。申请者前期研究发现电活性硫还原地杆菌能显著加速316L不锈钢的腐蚀，且胞外电子传递对腐蚀行为起到关键作用。本项目拟以此为基础，结合晶格光片显微镜，电化学工作站以及流动室系统，从单细胞水平实时观测硫还原地杆菌生物被膜在316L不锈钢材料表面生长，同时监控微生物腐蚀行为。并阐明胞外电子传递对硫还原地杆菌生物被膜成膜性的影响，以及成膜性的改变对腐蚀行为的影响。从单细胞水平，解析生物被膜在金属材料表面的形成过程能让人们对微生物腐蚀行为产生全新的认识，为电活性微生物腐蚀的靶向防治提供理论指导。

Microbiologically influenced corrosion (MIC) causes tremendous economic losses throughout the world. In the field of MIC, biofilms are usually investigated in terms of an ensemble. This strategy for studying MIC overlooks the heterogeneity, phenotypical diversity and dynamic development of biofilms. How these aforementioned features of biofilm affect its corrosion behavior have never been thoroughly studied. To answer this question, the formation of biofilms on the surface of materials must be resolved at single cell level. Our previous work demonstrated that the electroactive Geobacter species can significantly accelerate the corrosion of 316L stainless steel and extra-cellular electron transfer play critical role for the corrosion. Based on this work, we propose to study the formation of Geobacter sulfurreducens biofilms on the surface of 316L stainless steel and its corrosion behavior from single cell level by utilizing the combination of lattice light sheet microscope, electrochemical workstations and flow chamber systems. We also propose to clarify the effect of extra-cellular electron transfer on the development of G. sulfurreducens biofilms and how these effects influence its corrosion behavior. Investigation of biofilm development on the surface of metallic materials at single cell level could provide insight into understanding the MIC. The work of this project could provide theoretical foundations for the targeted prevention and control of MIC caused by electroactive microbial species.