title: Quorum signaling via AI-2 communicates the "Metabolic Burden" associated with heterologous protein production in Escherichia coli.
abstract: Recent reports have shown that bacterial cell-cell communication or quorum sensing is quite prevalent in pathogenic Escherichia coli, especially at high cell density; however, the role of quorum sensing in nonpathogenic E. coli is less clear and, in particular, there is no information regarding the role of quorum sensing in overexpression of plasmid-encoded genes. In this work, it was found that the activity of a quorum signaling molecule, autoinducer-2 (AI-2), decreased significantly following induction of several plasmid-encoded genes in both low and high-cell-density cultures of E. coli. Furthermore, we show that AI-2 signaling level was linearly related to the accumulation level of each protein product and that, in general, the highest rates of recombinant protein accumulation resulted in the greatest attenuation of AI-2 signaling. Importantly, our findings demonstrate for the first time that recombinant E. coli communicate the stress or burden of overexpressing heterologous genes through the quorum-based AI-2 signaling pathway.
authors.affiliation: Center for Agricultural Biotechnology, University of Maryland Biotechnological Institute, University of Maryland, College Park, MD, USA.
authors.forename: M P
authors.initials: MP
authors.lastname: DeLisa
authors.forename: J J
authors.initials: JJ
authors.lastname: Valdes
authors.forename: W E
authors.initials: WE
authors.lastname: Bentley
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism*; D019149:Bioreactors; D002450:Cell Communication; D002452:Cell Count; D017077:Culture Media, Conditioned; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D017930:Genes, Reporter; D006714:Homoserine / Q000031:analogs & derivatives* / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007376:Interleukin-2 / Q000378:metabolism; D007783:Lactones / Q000378:metabolism*; D049449:Luminescence; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D012995:Solubility; D013696:Temperature; D013997:Time Factors; D014733:Vibrio / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D017077:Culture Media, Conditioned; D007376:Interleukin-2; D007783:Lactones; C091088:N-octanoylhomoserine lactone; D011994:Recombinant Proteins; D006714:Homoserine