Title: | Methanol consumption drives the bacterial chloromethane sink in a forest soil |
Author(s): | Chaignaud P; Morawe M; Besaury L; Krober E; Vuilleumier S; Bringel F; Kolb S; |
Address: | "Department of Microbiology, Genomics and the Environment, Universite de Strasbourg, CNRS, GMGM UMR 7156, Strasbourg, France. Department of Ecological Microbiology, University of Bayreuth, Bayreuth, Germany. UMR FARE 614 Fractionnement des AgroRessources et Environnement, Chaire AFERE, INRA, Universite de Reims Champagne-Ardenne, Reims, France. Microbial Biogeochemistry, RA Landscape Functioning, ZALF Leibniz Centre for Landscape Research, Muncheberg, Germany. Department of Microbiology, Genomics and the Environment, Universite de Strasbourg, CNRS, GMGM UMR 7156, Strasbourg, France. francoise.bringel@unistra.fr. Microbial Biogeochemistry, RA Landscape Functioning, ZALF Leibniz Centre for Landscape Research, Muncheberg, Germany. Kolb@zalf.de" |
DOI: | 10.1038/s41396-018-0228-4 |
ISSN/ISBN: | 1751-7370 (Electronic) 1751-7362 (Print) 1751-7362 (Linking) |
Abstract: | "Halogenated volatile organic compounds (VOCs) emitted by terrestrial ecosystems, such as chloromethane (CH(3)Cl), have pronounced effects on troposphere and stratosphere chemistry and climate. The magnitude of the global CH(3)Cl sink is uncertain since it involves a largely uncharacterized microbial sink. CH(3)Cl represents a growth substrate for some specialized methylotrophs, while methanol (CH(3)OH), formed in much larger amounts in terrestrial environments, may be more widely used by such microorganisms. Direct measurements of CH(3)Cl degradation rates in two field campaigns and in microcosms allowed the identification of top soil horizons (i.e., organic plus mineral A horizon) as the major biotic sink in a deciduous forest. Metabolically active members of Alphaproteobacteria and Actinobacteria were identified by taxonomic and functional gene biomarkers following stable isotope labeling (SIP) of microcosms with CH(3)Cl and CH(3)OH, added alone or together as the [(13)C]-isotopologue. Well-studied reference CH(3)Cl degraders, such as Methylobacterium extorquens CM4, were not involved in the sink activity of the studied soil. Nonetheless, only sequences of the cmuA chloromethane dehalogenase gene highly similar to those of known strains were detected, suggesting the relevance of horizontal gene transfer for CH(3)Cl degradation in forest soil. Further, CH(3)Cl consumption rate increased in the presence of CH(3)OH. Members of Alphaproteobacteria and Actinobacteria were also (13)C-labeled upon [(13)C]-CH(3)OH amendment. These findings suggest that key bacterial CH(3)Cl degraders in forest soil benefit from CH(3)OH as an alternative substrate. For soil CH(3)Cl-utilizing methylotrophs, utilization of several one-carbon compounds may represent a competitive advantage over heterotrophs that cannot utilize one-carbon compounds" |
Keywords: | Actinobacteria/genetics/*metabolism Alphaproteobacteria/genetics/*metabolism Forests Methanol/*metabolism Methyl Chloride/*metabolism Soil/chemistry *Soil Microbiology; |
Notes: | "MedlineChaignaud, Pauline Morawe, Mareen Besaury, Ludovic Krober, Eileen Vuilleumier, Stephane Bringel, Francoise Kolb, Steffen eng Research Support, Non-U.S. Gov't England 2018/07/12 ISME J. 2018 Nov; 12(11):2681-2693. doi: 10.1038/s41396-018-0228-4. Epub 2018 Jul 10" |