Zargar, AminBacteria secrete and recognize communication molecules to coordinate gene expression in a process known as quorum sensing (QS). Through coordinated expression, bacteria are able to influence phenotypic changes on a larger population scale, such as biofilm formation. Recent studies into interkingdom communication have found cross-talk communication among bacteria and eukarya as well, which has been shown to influence actions pathogenicity and inflammation, among others. In this work, we developed E. coli ‘controller cells’ that guide and attenuate harmful bacterial QS phenotypes coordinated by the QS molecule autoinducer-2 (AI-2), as well as further the understanding of the interkingdom effects of these bacterial secretions (secretome) on human cells, particularly intestinal epithelial cells (IECs) that line the GI tract. Extending beyond natural networks, these ‘controller cells’ provide a useful tool in metabolic engineering, as synthetic biologists have incorporated QS networks to create sophisticated genetic circuits.enDissertationBiomedical engineering