title: Methods for analysis of bacterial autoinducer-2 production.
abstract: The quorum-sensing signal molecule autoinducer-2 (AI-2) is produced by over 50 diverse bacterial species and controls many different processes, including antibiotic production, biofilm formation, and virulence. AI-2 production often varies according to growth phase, media conditions, and the presence of specific factors. This unit describes a biological assay for AI-2 activity produced by a bacterial strain of interest. The assay employs an AI-2 reporter strain, Vibrio harveyi BB170, which produces light in response to AI-2. In the first stage of the assay, culture fluids of the bacterial strain of interest are collected over a time course of growth and filtered to remove cells. In the next stage, these culture fluids are mixed with BB170, and the light produced in response to AI-2 in the culture fluids is measured using a luminometer. BB170 is exquisitely sensitive to AI-2, and therefore, even low amounts of AI-2 can be detected using this bioassay.
authors.affiliation: Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
authors.forename: Michiko E
authors.initials: ME
authors.lastname: Taga
mesh_terms: D001419:Bacteria / Q000254:growth & development / Q000378:metabolism*; D003470:Culture Media / Q000737:chemistry; D006714:Homoserine / Q000031:analogs & derivatives* / Q000032:analysis / Q000378:metabolism; D007783:Lactones / Q000032:analysis* / Q000378:metabolism; D008163:Luminescent Measurements / Q000379:methods*; D014733:Vibrio / Q000254:growth & development / Q000378:metabolism
chemical_list: D003470:Culture Media; D007783:Lactones; C091088:N-octanoylhomoserine lactone; D006714:Homoserine