Sharing riboflavin as an electron shuttle enhances the corrosivity of a mixed consortium of Shewanella oneidensis and Bacillus licheniformis against 316L stainless steel

摘要

In nature, microbiologically influenced corrosion (MIC) is often caused by multi-species biofilms rather than single-species biofilms. In this work, the MIC of 316L stainless steel (SS) was investigated in the presence of individual and mixed consortium biofilms of Shewanella oneidensis and Bacillus licheniformis through electrochemical and surface characterizations. Results revealed that MIC of 316L SS was significantly accelerated by the biofilm consortium of S. oneidensis and B. licheniformis compared to single-species biofilms. It was found that the electron shuttle riboflavin secreted by S. oneidensis was utilized by B. licheniformis to accelerate the MIC of 316L SS, providing a new insight into multi-species microbial collaborations in extracellular electron transfer (EET)-MIC. (C) 2019 Elsevier Ltd. All rights reserved.