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Title: Metaproteomics reveals differential modes of metabolic coupling among ubiquitous oxygen minimum zone microbes

Abstract

Oxygen minimum zones (OMZs) are intrinsic water column features arising from respiratory oxygen demand during organic matter degradation in stratified marine waters. Currently OMZs are expanding due to global climate change. This expansion alters marine ecosystem function and the productivity of fisheries due to habitat compression and changes in biogeochemical cycling leading to fixed nitrogen loss and greenhouse gas production. Here we use metaproteomics to chart spatial and temporal patterns of gene expression along defined redox gradients in a seasonally anoxic fjord, Saanich Inlet to better understand microbial community responses to OMZ expansion. The expression of metabolic pathway components for nitrification, anaerobic ammonium oxidation (anammox), denitrification and inorganic carbon fixation predominantly co-varied with abundance and distribution patterns of Thaumarchaeota, Nitrospira, Planctomycetes and SUP05/ARCTIC96BD-19 Gammaproteobacteria. Within these groups, pathways mediating inorganic carbon fixation and nitrogen and sulfur transformations were differentially expressed across the redoxcline. Nitrification and inorganic carbon fixation pathways affiliated with Thaumarchaeota dominated dysoxic waters and denitrification, sulfur-oxidation and inorganic carbon fixation pathways affiliated with SUP05 dominated suboxic and anoxic waters. Nitrite-oxidation and anammox pathways affiliated with Nitrospina and Planctomycetes respectively, also exhibited redox partitioning between dysoxic and suboxic waters. The differential expression of these pathways under changing water columnmore » redox conditions has quantitative implications for coupled biogeochemical cycling linking different modes of inorganic carbon fixation with distributed nitrogen and sulfur-based energy metabolism extensible to coastal and open ocean OMZs.« less

Authors:
; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1170462
Report Number(s):
PNNL-SA-100391
47981; KP1704020
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Proceedings of the National Academy of Sciences of the United States of America, 111(31):11395-11400
Country of Publication:
United States
Language:
English
Subject:
Environmental Molecular Sciences Laboratory

Citation Formats

Hawley, Alyse K., Brewer, Heather M., Norbeck, Angela D., Pasa-Tolic, Ljiljana, and Hallam, Steven J. Metaproteomics reveals differential modes of metabolic coupling among ubiquitous oxygen minimum zone microbes. United States: N. p., 2014. Web. doi:10.1073/pnas.1322132111.
Hawley, Alyse K., Brewer, Heather M., Norbeck, Angela D., Pasa-Tolic, Ljiljana, & Hallam, Steven J. Metaproteomics reveals differential modes of metabolic coupling among ubiquitous oxygen minimum zone microbes. United States. doi:10.1073/pnas.1322132111.
Hawley, Alyse K., Brewer, Heather M., Norbeck, Angela D., Pasa-Tolic, Ljiljana, and Hallam, Steven J. Tue . "Metaproteomics reveals differential modes of metabolic coupling among ubiquitous oxygen minimum zone microbes". United States. doi:10.1073/pnas.1322132111.
@article{osti_1170462,
title = {Metaproteomics reveals differential modes of metabolic coupling among ubiquitous oxygen minimum zone microbes},
author = {Hawley, Alyse K. and Brewer, Heather M. and Norbeck, Angela D. and Pasa-Tolic, Ljiljana and Hallam, Steven J.},
abstractNote = {Oxygen minimum zones (OMZs) are intrinsic water column features arising from respiratory oxygen demand during organic matter degradation in stratified marine waters. Currently OMZs are expanding due to global climate change. This expansion alters marine ecosystem function and the productivity of fisheries due to habitat compression and changes in biogeochemical cycling leading to fixed nitrogen loss and greenhouse gas production. Here we use metaproteomics to chart spatial and temporal patterns of gene expression along defined redox gradients in a seasonally anoxic fjord, Saanich Inlet to better understand microbial community responses to OMZ expansion. The expression of metabolic pathway components for nitrification, anaerobic ammonium oxidation (anammox), denitrification and inorganic carbon fixation predominantly co-varied with abundance and distribution patterns of Thaumarchaeota, Nitrospira, Planctomycetes and SUP05/ARCTIC96BD-19 Gammaproteobacteria. Within these groups, pathways mediating inorganic carbon fixation and nitrogen and sulfur transformations were differentially expressed across the redoxcline. Nitrification and inorganic carbon fixation pathways affiliated with Thaumarchaeota dominated dysoxic waters and denitrification, sulfur-oxidation and inorganic carbon fixation pathways affiliated with SUP05 dominated suboxic and anoxic waters. Nitrite-oxidation and anammox pathways affiliated with Nitrospina and Planctomycetes respectively, also exhibited redox partitioning between dysoxic and suboxic waters. The differential expression of these pathways under changing water column redox conditions has quantitative implications for coupled biogeochemical cycling linking different modes of inorganic carbon fixation with distributed nitrogen and sulfur-based energy metabolism extensible to coastal and open ocean OMZs.},
doi = {10.1073/pnas.1322132111},
journal = {Proceedings of the National Academy of Sciences of the United States of America, 111(31):11395-11400},
number = ,
volume = ,
place = {United States},
year = {Tue Aug 05 00:00:00 EDT 2014},
month = {Tue Aug 05 00:00:00 EDT 2014}
}
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