Shewanella oneidensis is a Gram-negative,facultative anaerobe,widely found in natural environments.The bacterium is renowned for its respiratory versatility,which can utilize a diverse range of electron accepters for anaerobic respiration.However,little is known about how S.oneidensis cells respond to antibiotics although the subject is crucially relevant to the basic research and application.To this end,we used the pellicle (air-liquid interface biofilm) formation assay to study the response of S.oneidensis MR-1 to nine antibiotics.