title: Interkingdom Responses to Bacterial Quorum Sensing Signals Regulate Frequency and Rate of Nodulation in Legume-Rhizobia Symbiosis.
abstract: Density-dependent phenotypic switching in bacteria, the phenomenon of quorum sensing (QS), is instrumental in many pathogenic and mutualistic behaviors. In many Gram-negative bacteria, QS is regulated by N-acylated-l-homoserine lactones (AHLs). Synthetic analogues of these AHLs hold significant promise for regulating QS at the host-symbiont interface. Regulation depends on refined temporal and spatial models of quorums under native conditions. Critical to this is an understanding of how the presence of these signals may affect a prospective host. We screened a library of AHL analogues for their ability to regulate the legume-rhizobia mutualistic symbiosis (nodulation) between Medicago truncatula and Sinorhizobium meliloti. Using an established QS-reporter line of S. meliloti and nodulation assays with wild-type bacteria, we identified compounds capable of increasing either the rate of nodule formation or total nodule number. Most importantly, we identified compounds with activity exclusive to either host or pathogen, underscoring the potential to generate QS modulators selective to bacteria with limited effects on a prospective host.
authors.affiliation: Department of Biological Sciences, Florida Institute of Technology, 150 West University, Melbourne, FL, 32904, USA.
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Palmer
authors.affiliation: Department of Biology, University of Central Arkansas, 201 Donaghey, Conway, AK, 72035, USA.
authors.forename: Arijit
authors.initials: A
authors.lastname: Mukherjee
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI, 53706, USA.
authors.forename: Danielle M
authors.initials: DM
authors.lastname: Stacy
authors.affiliation: Department of Biological Sciences, Florida Institute of Technology, 150 West University, Melbourne, FL, 32904, USA.
authors.forename: Stephen
authors.initials: S
authors.lastname: Lazar
authors.affiliation: Department of Agronomy, University of Wisconsin-Madison, 1575 Linden Drive, Madison, WI, 53706, USA.|Department of Bacteriology, University of Wisconsin-Madison, 1550 Linden Drive, Madison, WI, 53706, USA.
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Ané
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI, 53706, USA.
authors.forename: Helen E
authors.initials: HE
authors.lastname: Blackwell
mesh_terms: D054742:Acyl-Butyrolactones / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D008024:Ligands; D046913:Medicago truncatula / Q000254:growth & development / Q000382:microbiology*; D055170:Plant Root Nodulation / Q000187:drug effects; D053038:Quorum Sensing / Q000502:physiology*; D016962:Sinorhizobium meliloti / Q000502:physiology*; D054852:Small Molecule Libraries / Q000737:chemistry; D013559:Symbiosis
chemical_list: D054742:Acyl-Butyrolactones; D008024:Ligands; D054852:Small Molecule Libraries
keywords: chemical biology; lactones; nodulation; plant growth regulation; quorum sensing