Quantitative Stable-Isotope Probing (qSIP) with Metagenomics Links Microbial Physiology and Activity to Soil Moisture in Mediterranean-Climate Grassland Ecosystems.

Autor:	Greenlon A; Department of Environmental Science, Policy and Management, University California, Berkeley, Berkley, California, USA., Sieradzki E; Department of Environmental Science, Policy and Management, University California, Berkeley, Berkley, California, USA., Zablocki O; Department of Microbiology, Ohio State University, Columbus, Ohio, USA.; Center of Microbiome Science, Ohio State University, Columbus, Ohio, USA., Koch BJ; Center for Ecosystem Science and Society, Northern Arizona Universitygrid.261120.6, Flagstaff, Arizona, USA.; Department of Biological Sciences, Northern Arizona Universitygrid.261120.6, Flagstaff, Arizona, USA., Foley MM; Center for Ecosystem Science and Society, Northern Arizona Universitygrid.261120.6, Flagstaff, Arizona, USA.; Department of Biological Sciences, Northern Arizona Universitygrid.261120.6, Flagstaff, Arizona, USA., Kimbrel JA; Physical and Life Sciences Directorate, Lawrence Livermore National Laboratorygrid.250008.f, Livermore, California, USA., Hungate BA; Center for Ecosystem Science and Society, Northern Arizona Universitygrid.261120.6, Flagstaff, Arizona, USA.; Department of Biological Sciences, Northern Arizona Universitygrid.261120.6, Flagstaff, Arizona, USA., Blazewicz SJ; Physical and Life Sciences Directorate, Lawrence Livermore National Laboratorygrid.250008.f, Livermore, California, USA., Nuccio EE; Physical and Life Sciences Directorate, Lawrence Livermore National Laboratorygrid.250008.f, Livermore, California, USA., Sun CL; Department of Microbiology, Ohio State University, Columbus, Ohio, USA.; Center of Microbiome Science, Ohio State University, Columbus, Ohio, USA., Chew A; Department of Environmental Science, Policy and Management, University California, Berkeley, Berkley, California, USA., Mancilla CJ; Department of Environmental Science, Policy and Management, University California, Berkeley, Berkley, California, USA., Sullivan MB; Department of Microbiology, Ohio State University, Columbus, Ohio, USA.; Center of Microbiome Science, Ohio State University, Columbus, Ohio, USA.; Department of Civil, Environmental and Geodetic Engineering, Ohio State University, Columbus, Ohio, USA., Firestone M; Department of Environmental Science, Policy and Management, University California, Berkeley, Berkley, California, USA., Pett-Ridge J; Physical and Life Sciences Directorate, Lawrence Livermore National Laboratorygrid.250008.f, Livermore, California, USA.; Life & Environmental Sciences Department, University of California, Merced, Merced, California, USA., Banfield JF; Department of Environmental Science, Policy and Management, University California, Berkeley, Berkley, California, USA.; Department of Earth and Planetary Science, University of California, Berkeleygrid.47840.3f, Berkley, California, USA.
Jazyk:	angličtina
Zdroj:	MSystems [mSystems] 2022 Dec 20; Vol. 7 (6), pp. e0041722. Date of Electronic Publication: 2022 Oct 27.
DOI:	10.1128/msystems.00417-22
Abstrakt:	The growth and physiology of soil microorganisms, which play vital roles in biogeochemical cycling, are shaped by both current and historical soil environmental conditions. Here, we developed and applied a genome-resolved metagenomic implementation of quantitative stable isotope probing (qSIP) with an H 2 18 O labeling experiment to identify actively growing soil microorganisms and their genomic capacities. qSIP enabled measurement of taxon-specific growth because isotopic incorporation into microbial DNA requires production of new genome copies. We studied three Mediterranean grassland soils across a rainfall gradient to evaluate the hypothesis that historic precipitation levels are an important factor controlling trait selection. We used qSIP-informed genome-resolved metagenomics to resolve the active subset of soil community members and identify their characteristic ecophysiological traits. Higher year-round precipitation levels correlated with higher activity and growth rates of flagellar motile microorganisms. In addition to heavily isotopically labeled bacteria, we identified abundant isotope-labeled phages, suggesting phage-induced cell lysis likely contributed to necromass production at all three sites. Further, there was a positive correlation between phage activity and the activity of putative phage hosts. Contrary to our expectations, the capacity to decompose the diverse complex carbohydrates common in soil organic matter or oxidize methanol and carbon monoxide were broadly distributed across active and inactive bacteria in all three soils, implying that these traits are not highly selected for by historical precipitation. IMPORTANCE Soil moisture is a critical factor that strongly shapes the lifestyle of soil organisms by changing access to nutrients, controlling oxygen diffusion, and regulating the potential for mobility. We identified active microorganisms in three grassland soils with similar mineral contexts, yet different historic rainfall inputs, by adding water labeled with a stable isotope and tracking that isotope in DNA of growing microbes. By examining the genomes of active and inactive microorganisms, we identified functions that are enriched in growing organisms, and showed that different functions were selected for in different soils. Wetter soil had higher activity of motile organisms, but activity of pathways for degradation of soil organic carbon compounds, including simple carbon substrates, were comparable for all three soils. We identified many labeled, and thus active bacteriophages (viruses that infect bacteria), implying that the cells they killed contributed to soil organic matter. The activity of these bacteriophages was significantly correlated with activity of their hosts.
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu