Formate, acetate, and propionate as substrates for sulfate reduction in sub-arctic sediments of Southwest Greenland
Volatile fatty acids (VFAs) are key intermediates in the anaerobic mineralization of organic matter in marine sediments. We studied the role of VFAs in the carbon and energy turnover in the sulfate reduction zone of sediments from the sub-arctic Godthåbsfjord (SW Greenland) and the adjacent continen...
Published in: | Frontiers in Microbiology |
---|---|
Main Authors: | , , , , , |
Format: | Text |
Language: | English |
Published: |
Frontiers Media S.A.
2015
|
Subjects: | |
Online Access: | http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4547046/ https://doi.org/10.3389/fmicb.2015.00846 |
id |
ftpubmed:oai:pubmedcentral.nih.gov:4547046 |
---|---|
record_format |
openpolar |
spelling |
ftpubmed:oai:pubmedcentral.nih.gov:4547046 2023-05-15T15:02:03+02:00 Formate, acetate, and propionate as substrates for sulfate reduction in sub-arctic sediments of Southwest Greenland Glombitza, Clemens Jaussi, Marion Røy, Hans Seidenkrantz, Marit-Solveig Lomstein, Bente A. Jørgensen, Bo B. 2015-08-24 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4547046/ https://doi.org/10.3389/fmicb.2015.00846 en eng Frontiers Media S.A. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4547046/ http://dx.doi.org/10.3389/fmicb.2015.00846 Copyright © 2015 Glombitza, Jaussi, Røy, Seidenkrantz, Lomstein and Jørgensen. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. CC-BY Microbiology Text 2015 ftpubmed https://doi.org/10.3389/fmicb.2015.00846 2015-09-20T00:09:35Z Volatile fatty acids (VFAs) are key intermediates in the anaerobic mineralization of organic matter in marine sediments. We studied the role of VFAs in the carbon and energy turnover in the sulfate reduction zone of sediments from the sub-arctic Godthåbsfjord (SW Greenland) and the adjacent continental shelf in the NE Labrador Sea. VFA porewater concentrations were measured by a new two-dimensional ion chromatography-mass spectrometry method that enabled the direct analysis of VFAs without sample pretreatment. VFA concentrations were low and surprisingly constant (4–6 μmol L−1 for formate and acetate, and 0.5 μmol L−1 for propionate) throughout the sulfate reduction zone. Hence, VFAs are turned over while maintaining a stable concentration that is suggested to be under a strong microbial control. Estimated mean diffusion times of acetate between neighboring cells were <1 s, whereas VFA turnover times increased from several hours at the sediment surface to several years at the bottom of the sulfate reduction zone. Thus, diffusion was not limiting the VFA turnover. Despite constant VFA concentrations, the Gibbs energies (ΔGr) of VFA-dependent sulfate reduction decreased downcore, from −28 to −16 kJ (mol formate)−1, −68 to −31 kJ (mol acetate)−1, and −124 to −65 kJ (mol propionate)−1. Thus, ΔGr is apparently not determining the in-situ VFA concentrations directly. However, at the bottom of the sulfate zone of the shelf station, acetoclastic sulfate reduction might operate at its energetic limit at ~ −30 kJ (mol acetate)−1. It is not clear what controls VFA concentrations in the porewater but cell physiological constraints such as energetic costs of VFA activation or uptake could be important. We suggest that such constraints control the substrate turnover and result in a minimum ΔGr that depends on cell physiology and is different for individual substrates. Text Arctic Godthåbsfjord Greenland Labrador Sea PubMed Central (PMC) Arctic Greenland Frontiers in Microbiology 6 |
institution |
Open Polar |
collection |
PubMed Central (PMC) |
op_collection_id |
ftpubmed |
language |
English |
topic |
Microbiology |
spellingShingle |
Microbiology Glombitza, Clemens Jaussi, Marion Røy, Hans Seidenkrantz, Marit-Solveig Lomstein, Bente A. Jørgensen, Bo B. Formate, acetate, and propionate as substrates for sulfate reduction in sub-arctic sediments of Southwest Greenland |
topic_facet |
Microbiology |
description |
Volatile fatty acids (VFAs) are key intermediates in the anaerobic mineralization of organic matter in marine sediments. We studied the role of VFAs in the carbon and energy turnover in the sulfate reduction zone of sediments from the sub-arctic Godthåbsfjord (SW Greenland) and the adjacent continental shelf in the NE Labrador Sea. VFA porewater concentrations were measured by a new two-dimensional ion chromatography-mass spectrometry method that enabled the direct analysis of VFAs without sample pretreatment. VFA concentrations were low and surprisingly constant (4–6 μmol L−1 for formate and acetate, and 0.5 μmol L−1 for propionate) throughout the sulfate reduction zone. Hence, VFAs are turned over while maintaining a stable concentration that is suggested to be under a strong microbial control. Estimated mean diffusion times of acetate between neighboring cells were <1 s, whereas VFA turnover times increased from several hours at the sediment surface to several years at the bottom of the sulfate reduction zone. Thus, diffusion was not limiting the VFA turnover. Despite constant VFA concentrations, the Gibbs energies (ΔGr) of VFA-dependent sulfate reduction decreased downcore, from −28 to −16 kJ (mol formate)−1, −68 to −31 kJ (mol acetate)−1, and −124 to −65 kJ (mol propionate)−1. Thus, ΔGr is apparently not determining the in-situ VFA concentrations directly. However, at the bottom of the sulfate zone of the shelf station, acetoclastic sulfate reduction might operate at its energetic limit at ~ −30 kJ (mol acetate)−1. It is not clear what controls VFA concentrations in the porewater but cell physiological constraints such as energetic costs of VFA activation or uptake could be important. We suggest that such constraints control the substrate turnover and result in a minimum ΔGr that depends on cell physiology and is different for individual substrates. |
format |
Text |
author |
Glombitza, Clemens Jaussi, Marion Røy, Hans Seidenkrantz, Marit-Solveig Lomstein, Bente A. Jørgensen, Bo B. |
author_facet |
Glombitza, Clemens Jaussi, Marion Røy, Hans Seidenkrantz, Marit-Solveig Lomstein, Bente A. Jørgensen, Bo B. |
author_sort |
Glombitza, Clemens |
title |
Formate, acetate, and propionate as substrates for sulfate reduction in sub-arctic sediments of Southwest Greenland |
title_short |
Formate, acetate, and propionate as substrates for sulfate reduction in sub-arctic sediments of Southwest Greenland |
title_full |
Formate, acetate, and propionate as substrates for sulfate reduction in sub-arctic sediments of Southwest Greenland |
title_fullStr |
Formate, acetate, and propionate as substrates for sulfate reduction in sub-arctic sediments of Southwest Greenland |
title_full_unstemmed |
Formate, acetate, and propionate as substrates for sulfate reduction in sub-arctic sediments of Southwest Greenland |
title_sort |
formate, acetate, and propionate as substrates for sulfate reduction in sub-arctic sediments of southwest greenland |
publisher |
Frontiers Media S.A. |
publishDate |
2015 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4547046/ https://doi.org/10.3389/fmicb.2015.00846 |
geographic |
Arctic Greenland |
geographic_facet |
Arctic Greenland |
genre |
Arctic Godthåbsfjord Greenland Labrador Sea |
genre_facet |
Arctic Godthåbsfjord Greenland Labrador Sea |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4547046/ http://dx.doi.org/10.3389/fmicb.2015.00846 |
op_rights |
Copyright © 2015 Glombitza, Jaussi, Røy, Seidenkrantz, Lomstein and Jørgensen. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.3389/fmicb.2015.00846 |
container_title |
Frontiers in Microbiology |
container_volume |
6 |
_version_ |
1766334047135465472 |