Sela, S., Microbial Food-Safety Research Unit, Department of Food Sciences, Institute for Technology and Storage of Fresh Produce, Beth-Dagan, Israel, Department of Food Sciences, ARO, Volcani Center, Beth-Dagan 50250, Israel
Frank, S., Microbial Food-Safety Research Unit, Department of Food Sciences, Institute for Technology and Storage of Fresh Produce, Beth-Dagan, Israel
Belausov, E., Confocal Microscopy Unit, Agricultural Research Organization (ARO), Volcani Center, Beth-Dagan, Israel
Pinto, R., Microbial Food-Safety Research Unit, Department of Food Sciences, Institute for Technology and Storage of Fresh Produce, Beth-Dagan, Israel

Using a Vibrio harveyi reporter strain, we demonstrated that Listeria monocytogenes secretes a functional autoinducer 2 (AI-2)-like signal. A luxS-deficient mutant produced a denser biofilm and attached to a glass surface 19-fold better than the parent strain. Exogenous AI-2 failed to restore the wild-type phenotype to the mutant. It seems that an intact luxS gene is associated with repression of components required for attachment and biofilm formation. Copyright © 2006, American Society for Microbiology. All Rights Reserved.