Active efflux pump that plays an important role in chloramphenicol resistance (PubMed:31054279). Overexpression causes pyrazinamide resistance (PubMed:28584158). Inhibited by the drug efflux pump inhibitors verapamil, resperine, piperine, chlorpromazine and carbonyl cyanide m-chlorophenylhydrazone (CCCP). Expression is negatively regulated by the transcriptional repressor Rv1353c. Belongs to the major facilitator superfamily.