Abstract
Microbes can cause or accelerate metal corrosion,leading to huge losses in corrosion damages each year.Geobacter sulfurreducens is a representative electroactive bacterium in many soils,sediments,and wastew-ater systems.It has been confirmed to directly extract electrons from elemental metals.However,little is known about the effect of electron shuttles in G.sulfurreducens corrosion on stainless steel.In this study,we report that exogenous flavins promote iron-to-microbe electron transfer,accelerating micro-bial corrosion.G.sulfurreducens caused 1.3 times deeper pits and increased electron uptake(with 2 times increase of icorr)from stainless steel when riboflavin was added to the culture medium.OmcS-deficient mutant data suggest that G.sulfurreducens utilizes riboflavin as a bound-cofactor in outer membrane c-type cytochromes.The finding that,in the presence of microbes,riboflavin can substantially accelerate corrosion highlights the role of flavin redox cycling for enhanced iron-to-microbe electron transfer by G.sulfurreducens and provides new insights in microbial corrosion.
基金项目
National Natural Science Foundation of China(52101078)
National Natural Science Foundation of China(U2006219)
National Key Research and Development Program of China(2020YFA0907300)
Fundamental Research Funds for the Central Universities of the Ministry of Education of China(N2102009)
Fundamental Research Funds for the Central Universities of the Ministry of Education of China(N2002019)
Liaoning Revitalization Talents Program(XLYC1907158)
NETL
NSTL
万方数据