title: A novel pathway producing dimethylsulphide in bacteria is widespread in soil environments.
abstract: The volatile compound dimethylsulphide (DMS) is important in climate regulation, the sulphur cycle and signalling to higher organisms. Microbial catabolism of the marine osmolyte dimethylsulphoniopropionate (DMSP) is thought to be the major biological process generating DMS. Here we report the discovery and characterization of the first gene for DMSP-independent DMS production in any bacterium. This gene, mddA, encodes a methyltransferase that methylates methanethiol and generates DMS. MddA functions in many taxonomically diverse bacteria including sediment-dwelling pseudomonads, nitrogen-fixing bradyrhizobia and cyanobacteria, and mycobacteria including the pathogen Mycobacterium tuberculosis. The mddA gene is present in metagenomes from varied environments, being particularly abundant in soil environments, where it is predicted to occur in up to 76% of bacteria. This novel pathway may significantly contribute to global DMS emissions, especially in terrestrial environments and could represent a shift from the notion that DMSP is the only significant precursor of DMS.
authors: Laboratori de Microbiologia, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII s/n, 08028 Barcelona, Spain.
authors: O
authors: O
authors: Carrión
authors: School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK.
authors: A R J
authors: ARJ
authors: Curson
authors: School of Earth and Environment, University of Western Australia, Crawley, Perth, Western Australia 6009, Australia.
authors: D
authors: D
authors: Kumaresan
authors: Department of Biology, Memorial University of Newfoundland, 232 Elizabeth Avenue, St John's, Newfoundland and Labrador, A1B 3X9, Canada.
authors: Y
authors: Y
authors: Fu
authors: Department of Biology, Memorial University of Newfoundland, 232 Elizabeth Avenue, St John's, Newfoundland and Labrador, A1B 3X9, Canada.
authors: A S
authors: AS
authors: Lang
authors: Laboratori de Microbiologia, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII s/n, 08028 Barcelona, Spain.
authors: E
authors: E
authors: Mercadé
authors: School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK.
authors: J D
authors: JD
authors: Todd
mesh_terms: D000595:Amino Acid Sequence; D020369:Bradyrhizobium / Q000235:genetics; D013437:Carbon-Sulfur Lyases / Q000235:genetics; D046889:Cyanothece / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D054892:Metagenome; D008780:Methyltransferases / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D011549:Pseudomonas / Q000235:genetics; D016961:Rhizobium leguminosarum / Q000235:genetics; D012988:Soil Microbiology; D013438:Sulfhydryl Compounds / Q000378:metabolism; D013440:Sulfides / Q000138:chemical synthesis*; D013452:Sulfonium Compounds / Q000378:metabolism
chemical_list: D013438:Sulfhydryl Compounds; D013440:Sulfides; D013452:Sulfonium Compounds; C005231:methylmercaptan; C068078:dimethylpropiothetin; D008780:Methyltransferases; D013437:Carbon-Sulfur Lyases; C021558:L-methionine gamma-lyase; C004784:dimethyl sulfide