title: Microorganisms with novel dissimilatory (bi)sulfite reductase genes are widespread and part of the core microbiota in low-sulfate peatlands.
abstract: Peatlands of the Lehstenbach catchment (Germany) house as-yet-unidentified microorganisms with phylogenetically novel variants of the dissimilatory (bi)sulfite reductase genes dsrAB. These genes are characteristic of microorganisms that reduce sulfate, sulfite, or some organosulfonates for energy conservation but can also be present in anaerobic syntrophs. However, nothing is currently known regarding the abundance, community dynamics, and biogeography of these dsrAB-carrying microorganisms in peatlands. To tackle these issues, soils from a Lehstenbach catchment site (Schlöppnerbrunnen II fen) from different depths were sampled at three time points over a 6-year period to analyze the diversity and distribution of dsrAB-containing microorganisms by a newly developed functional gene microarray and quantitative PCR assays. Members of novel, uncultivated dsrAB lineages (approximately representing species-level groups) (i) dominated a temporally stable but spatially structured dsrAB community and (ii) represented "core" members (up to 1% to 1.7% relative abundance) of the autochthonous microbial community in this fen. In addition, denaturing gradient gel electrophoresis (DGGE)- and clone library-based comparisons of the dsrAB diversity in soils from a wet meadow, three bogs, and five fens of various geographic locations (distance of ∼1 to 400 km) identified that one Syntrophobacter-related and nine novel dsrAB lineages are widespread in low-sulfate peatlands. Signatures of biogeography in dsrB-based DGGE data were not correlated with geographic distance but could be explained largely by soil pH and wetland type, implying that the distribution of dsrAB-carrying microorganisms in wetlands on the scale of a few hundred kilometers is not limited by dispersal but determined by local environmental conditions.
authors.affiliation: Department of Microbial Ecology, Vienna Ecology Center, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria.
authors.forename: Doris
authors.initials: D
authors.lastname: Steger
authors.forename: Cecilia
authors.initials: C
authors.lastname: Wentrup
authors.forename: Christina
authors.initials: C
authors.lastname: Braunegger
authors.forename: Pinsurang
authors.initials: P
authors.lastname: Deevong
authors.forename: Manuel
authors.initials: M
authors.lastname: Hofer
authors.forename: Andreas
authors.initials: A
authors.lastname: Richter
authors.forename: Christian
authors.initials: C
authors.lastname: Baranyi
authors.forename: Michael
authors.initials: M
authors.lastname: Pester
authors.forename: Michael
authors.initials: M
authors.lastname: Wagner
authors.forename: Alexander
authors.initials: A
authors.lastname: Loy
mesh_terms: D000476:Alkanesulfonates / Q000378:metabolism; D001419:Bacteria / Q000201:enzymology / Q000235:genetics*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D058645:Denaturing Gradient Gel Electrophoresis; D004777:Environment; D015723:Gene Library; D014644:Genetic Variation; D019015:Geologic Sediments; D005858:Germany; D050885:Hydrogensulfite Reductase / Q000235:genetics* / Q000378:metabolism; D054892:Metagenome / Q000235:genetics*; D046228:Microarray Analysis; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D012987:Soil; D012988:Soil Microbiology; D013431:Sulfates / Q000378:metabolism; D013447:Sulfites / Q000378:metabolism; D016999:Sulfur-Reducing Bacteria / Q000201:enzymology / Q000235:genetics*; D053833:Wetlands
chemical_list: D000476:Alkanesulfonates; D004269:DNA, Bacterial; D012987:Soil; D013431:Sulfates; D013447:Sulfites; D050885:Hydrogensulfite Reductase