skip to main content

Title: Metabolic potential of fatty acid oxidation and anaerobic respiration by abundant members of Thaumarchaeota and Thermoplasmata in deep anoxic peat

To probe the metabolic potential of abundant Archaea in boreal peats, we reconstructed two near-complete archaeal genomes, affiliated with Thaumarchaeota group 1.1c (bin Fn1, 8% abundance), which was a genomically unrepresented group, and Thermoplasmata (bin Bg1, 26% abundance), from metagenomic data acquired from deep anoxic peat layers. Each of the near-complete genomes encodes the potential to degrade long-chain fatty acids (LCFA) via β-oxidation. Fn1 has the potential to oxidize LCFA either by syntrophic interaction with methanogens or by coupling oxidation with anaerobic respiration using fumarate as a terminal electron acceptor (TEA). Fn1 is the first Thaumarchaeota genome without an identifiable carbon fixation pathway, indicating that this mesophilic phylum encompasses more diverse metabolisms than previously thought. Furthermore, we report genetic evidence suggestive of sulfite and/or organosulfonate reduction by Thermoplasmata Bg1. In deep peat, inorganic TEAs are often depleted to extremely low levels, yet the anaerobic respiration predicted for two abundant archaeal members suggests organic electron acceptors such as fumarate and organosulfonate (enriched in humic substances) may be important for respiration and C mineralization in peatlands.
Authors:
 [1] ;  [2] ;  [3] ;  [1]
  1. Georgia Inst. of Technology, Atlanta, GA (United States)
  2. Univ. of Chicago, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States)
  3. Univ. of Chicago, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States); Marine Biological Lab., Woods Hole, MA (United States); Zhejiang Univ., Hangzhou (China)
Publication Date:
OSTI Identifier:
1247153
Grant/Contract Number:
AC02-06CH11357
Type:
Accepted Manuscript
Journal Name:
The ISME Journal
Additional Journal Information:
Journal Volume: 9; Journal Issue: 12; Journal ID: ISSN 1751-7362
Publisher:
Nature Publishing Group
Research Org:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org:
National Science Foundation (NSF); Alfred P. Sloan Foundation; USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES