title: Quorum Sensing in a Methane-Oxidizing Bacterium.
abstract: Aerobic methanotrophic bacteria use methane as their sole source of carbon and energy and serve as a major sink for the potent greenhouse gas methane in freshwater ecosystems. Dissecting the molecular details of how these organisms interact in the environment may increase our understanding of how they perform this important ecological role. Many bacterial species use quorum sensing (QS) systems to regulate gene expression in a cell density-dependent manner. We have identified a QS system in the genome ofMethylobacter tundripaludum, a dominant methane oxidizer in methane enrichments of sediment from Lake Washington (Seattle, WA). We determined thatM. tundripaludumproduces primarilyN-3-hydroxydecanoyl-l-homoserine lactone (3-OH-C10-HSL) and that its production is governed by a positive feedback loop. We then further characterized this system by determining which genes are regulated by QS in this methane oxidizer using transcriptome sequencing (RNA-seq) and discovered that this system regulates the expression of a putative nonribosomal peptide synthetase biosynthetic gene cluster. Finally, we detected an extracellular factor that is produced byM. tundripaludumin a QS-dependent manner. These results identify and characterize a mode of cellular communication in an aerobic methane-oxidizing bacterium.IMPORTANCEAerobic methanotrophs are critical for sequestering carbon from the potent greenhouse gas methane in the environment, yet the mechanistic details of chemical interactions in methane-oxidizing bacterial communities are not well understood. Understanding these interactions is important in order to maintain, and potentially optimize, the functional potential of the bacteria that perform this vital ecosystem function. In this work, we identify a quorum sensing system in the aerobic methanotrophMethylobacter tundripaludumand use both chemical and genetic methods to characterize this system at the molecular level.
authors.affiliation: Department of Chemical Engineering, University of Washington, Seattle, Washington, USA awpuri@uw.edu.
authors.forename: Aaron W
authors.identifier: http://orcid.org/0000-0002-6378-678X
authors.initials: AW
authors.lastname: Puri
authors.affiliation: Department of Microbiology, University of Washington, Seattle, Washington, USA.
authors.forename: Amy L
authors.initials: AL
authors.lastname: Schaefer
authors.affiliation: Department of Chemical Engineering, University of Washington, Seattle, Washington, USA.
authors.forename: Yanfen
authors.initials: Y
authors.lastname: Fu
authors.affiliation: Department of Chemical Engineering, University of Washington, Seattle, Washington, USA.|eScience Institute, University of Washington, Seattle, Washington, USA.
authors.forename: David A C
authors.initials: DAC
authors.lastname: Beck
authors.affiliation: Department of Microbiology, University of Washington, Seattle, Washington, USA.
authors.forename: E Peter
authors.initials: EP
authors.lastname: Greenberg
authors.affiliation: Department of Chemical Engineering, University of Washington, Seattle, Washington, USA.|Department of Microbiology, University of Washington, Seattle, Washington, USA.
authors.forename: Mary E
authors.initials: ME
authors.lastname: Lidstrom
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D007700:Kinetics; D008697:Methane / Q000378:metabolism*; D008772:Methylococcaceae / Q000502:physiology*; D010084:Oxidation-Reduction; D053038:Quorum Sensing / Q000502:physiology*; D015398:Signal Transduction
chemical_list: D001426:Bacterial Proteins; D008697:Methane
keywords: acyl-homoserine lactone; biosynthetic gene cluster; methane; methanotroph; quorum sensing; sociomicrobiology