title: Pyrones as bacterial signaling molecules.
abstract: Bacteria communicate via small diffusible molecules and thereby mediate group-coordinated behavior, a process referred to as quorum sensing. The prototypical quorum sensing system found in Gram-negative bacteria consists of a LuxI-type autoinducer synthase that produces N-acyl homoserine lactones (AHLs) as signals and a LuxR-type receptor that detects the AHLs to control expression of specific genes. However, many proteobacteria have proteins with homology to LuxR receptors yet lack any cognate LuxI-like AHL synthase. Here we show that in the insect pathogen Photorhabdus luminescens the orphan LuxR-type receptor PluR detects endogenously produced α-pyrones that serve as signaling molecules at low nanomolar concentrations. Additionally, the ketosynthase PpyS was identified as pyrone synthase. Reconstitution of the entire system containing PluR, the PluR-target operon we termed pcf and PpyS in Escherichia coli demonstrated that the cell-cell communication circuit is portable. Our research thus deorphanizes a signaling system and suggests that additional modes of bacterial communication may await discovery.
authors.affiliation: 1] Merck Stiftungsprofessur für Molekulare Biotechnologie, Goethe-Universität Frankfurt, Frankfurt, Germany. [2].
authors.forename: Alexander O
authors.initials: AO
authors.lastname: Brachmann
authors.forename: Sophie
authors.initials: S
authors.lastname: Brameyer
authors.forename: Darko
authors.initials: D
authors.lastname: Kresovic
authors.forename: Ivana
authors.initials: I
authors.lastname: Hitkova
authors.forename: Yannick
authors.initials: Y
authors.lastname: Kopp
authors.forename: Christian
authors.initials: C
authors.lastname: Manske
authors.forename: Karin
authors.initials: K
authors.lastname: Schubert
authors.forename: Helge B
authors.initials: HB
authors.lastname: Bode
authors.forename: Ralf
authors.initials: R
authors.lastname: Heermann
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009876:Operon / Q000235:genetics; D020637:Photorhabdus / Q000737:chemistry / Q000378:metabolism*; D011753:Pyrones / Q000737:chemistry / Q000378:metabolism*; D053038:Quorum Sensing; D015398:Signal Transduction
chemical_list: D001426:Bacterial Proteins; D011753:Pyrones