Stimulated Bacterial Growth under Elevated p Co2: Results from an Off-Shore Mesocosm Study
Marine bacteria are the main consumers of freshly produced organic matter. Many enzymatic processes involved in the bacterial digestion of organic compounds were shown to be pH sensitive in previous studies. Due to the continuous rise in atmospheric CO2 concentration, seawater pH is presently decrea...
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Public Library of Science
2014
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Online Access: | https://oceanrep.geomar.de/id/eprint/24853/ https://oceanrep.geomar.de/id/eprint/24853/1/Endre%20et%20al%202014.pdf https://oceanrep.geomar.de/id/eprint/24853/17/Figure_S1.tif https://oceanrep.geomar.de/id/eprint/24853/2/Figure_S2.tif https://oceanrep.geomar.de/id/eprint/24853/3/Figure_S3.tif https://doi.org/10.1371/journal.pone.0099228 |
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ftoceanrep:oai:oceanrep.geomar.de:24853 2023-05-15T17:52:05+02:00 Stimulated Bacterial Growth under Elevated p Co2: Results from an Off-Shore Mesocosm Study Endres, Sonja Galgani, Luisa Riebesell, Ulf Schulz, Kai G. Engel, Anja 2014-06-18 text image https://oceanrep.geomar.de/id/eprint/24853/ https://oceanrep.geomar.de/id/eprint/24853/1/Endre%20et%20al%202014.pdf https://oceanrep.geomar.de/id/eprint/24853/17/Figure_S1.tif https://oceanrep.geomar.de/id/eprint/24853/2/Figure_S2.tif https://oceanrep.geomar.de/id/eprint/24853/3/Figure_S3.tif https://doi.org/10.1371/journal.pone.0099228 en eng Public Library of Science https://oceanrep.geomar.de/id/eprint/24853/1/Endre%20et%20al%202014.pdf https://oceanrep.geomar.de/id/eprint/24853/17/Figure_S1.tif https://oceanrep.geomar.de/id/eprint/24853/2/Figure_S2.tif https://oceanrep.geomar.de/id/eprint/24853/3/Figure_S3.tif Endres, S. , Galgani, L., Riebesell, U. , Schulz, K. G. and Engel, A. (2014) Stimulated Bacterial Growth under Elevated p Co2: Results from an Off-Shore Mesocosm Study. Open Access PLoS ONE, 9 (6). e99228. DOI 10.1371/journal.pone.0099228 <https://doi.org/10.1371/journal.pone.0099228>. doi:10.1371/journal.pone.0099228 cc_by info:eu-repo/semantics/openAccess Article PeerReviewed 2014 ftoceanrep https://doi.org/10.1371/journal.pone.0099228 2023-04-07T15:13:38Z Marine bacteria are the main consumers of freshly produced organic matter. Many enzymatic processes involved in the bacterial digestion of organic compounds were shown to be pH sensitive in previous studies. Due to the continuous rise in atmospheric CO2 concentration, seawater pH is presently decreasing at a rate unprecedented during the last 300 million years but the consequences for microbial physiology, organic matter cycling and marine biogeochemistry are still unresolved. We studied the effects of elevated seawater pCO2 on a natural plankton community during a large-scale mesocosm study in a Norwegian fjord. Nine Kiel Off-Shore Mesocosms for Future Ocean Simulations (KOSMOS) were adjusted to different pCO2 levels ranging initially from ca. 280 to 3000 µatm and sampled every second day for 34 days. The first phytoplankton bloom developed around day 5. On day 14, inorganic nutrients were added to the enclosed, nutrient-poor waters to stimulate a second phytoplankton bloom, which occurred around day 20. Our results indicate that marine bacteria benefit directly and indirectly from decreasing seawater pH. During the first phytoplankton bloom, 5–10% more transparent exopolymer particles were formed in the high pCO2 mesocosms. Simultaneously, the efficiency of the protein-degrading enzyme leucine aminopeptidase increased with decreasing pH resulting in up to three times higher values in the highest pCO2/lowest pH mesocosm compared to the controls. In general, total and cell-specific aminopeptidase activities were elevated under low pH conditions. The combination of enhanced enzymatic hydrolysis of organic matter and increased availability of gel particles as substrate supported up to 28% higher bacterial abundance in the high pCO2 treatments. We conclude that ocean acidification has the potential to stimulate the bacterial community and facilitate the microbial recycling of freshly produced organic matter, thus strengthening the role of the microbial loop in the surface ocean. Article in Journal/Newspaper Ocean acidification OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) PLoS ONE 9 6 e99228 |
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Open Polar |
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OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
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ftoceanrep |
language |
English |
description |
Marine bacteria are the main consumers of freshly produced organic matter. Many enzymatic processes involved in the bacterial digestion of organic compounds were shown to be pH sensitive in previous studies. Due to the continuous rise in atmospheric CO2 concentration, seawater pH is presently decreasing at a rate unprecedented during the last 300 million years but the consequences for microbial physiology, organic matter cycling and marine biogeochemistry are still unresolved. We studied the effects of elevated seawater pCO2 on a natural plankton community during a large-scale mesocosm study in a Norwegian fjord. Nine Kiel Off-Shore Mesocosms for Future Ocean Simulations (KOSMOS) were adjusted to different pCO2 levels ranging initially from ca. 280 to 3000 µatm and sampled every second day for 34 days. The first phytoplankton bloom developed around day 5. On day 14, inorganic nutrients were added to the enclosed, nutrient-poor waters to stimulate a second phytoplankton bloom, which occurred around day 20. Our results indicate that marine bacteria benefit directly and indirectly from decreasing seawater pH. During the first phytoplankton bloom, 5–10% more transparent exopolymer particles were formed in the high pCO2 mesocosms. Simultaneously, the efficiency of the protein-degrading enzyme leucine aminopeptidase increased with decreasing pH resulting in up to three times higher values in the highest pCO2/lowest pH mesocosm compared to the controls. In general, total and cell-specific aminopeptidase activities were elevated under low pH conditions. The combination of enhanced enzymatic hydrolysis of organic matter and increased availability of gel particles as substrate supported up to 28% higher bacterial abundance in the high pCO2 treatments. We conclude that ocean acidification has the potential to stimulate the bacterial community and facilitate the microbial recycling of freshly produced organic matter, thus strengthening the role of the microbial loop in the surface ocean. |
format |
Article in Journal/Newspaper |
author |
Endres, Sonja Galgani, Luisa Riebesell, Ulf Schulz, Kai G. Engel, Anja |
spellingShingle |
Endres, Sonja Galgani, Luisa Riebesell, Ulf Schulz, Kai G. Engel, Anja Stimulated Bacterial Growth under Elevated p Co2: Results from an Off-Shore Mesocosm Study |
author_facet |
Endres, Sonja Galgani, Luisa Riebesell, Ulf Schulz, Kai G. Engel, Anja |
author_sort |
Endres, Sonja |
title |
Stimulated Bacterial Growth under Elevated p Co2: Results from an Off-Shore Mesocosm Study |
title_short |
Stimulated Bacterial Growth under Elevated p Co2: Results from an Off-Shore Mesocosm Study |
title_full |
Stimulated Bacterial Growth under Elevated p Co2: Results from an Off-Shore Mesocosm Study |
title_fullStr |
Stimulated Bacterial Growth under Elevated p Co2: Results from an Off-Shore Mesocosm Study |
title_full_unstemmed |
Stimulated Bacterial Growth under Elevated p Co2: Results from an Off-Shore Mesocosm Study |
title_sort |
stimulated bacterial growth under elevated p co2: results from an off-shore mesocosm study |
publisher |
Public Library of Science |
publishDate |
2014 |
url |
https://oceanrep.geomar.de/id/eprint/24853/ https://oceanrep.geomar.de/id/eprint/24853/1/Endre%20et%20al%202014.pdf https://oceanrep.geomar.de/id/eprint/24853/17/Figure_S1.tif https://oceanrep.geomar.de/id/eprint/24853/2/Figure_S2.tif https://oceanrep.geomar.de/id/eprint/24853/3/Figure_S3.tif https://doi.org/10.1371/journal.pone.0099228 |
genre |
Ocean acidification |
genre_facet |
Ocean acidification |
op_relation |
https://oceanrep.geomar.de/id/eprint/24853/1/Endre%20et%20al%202014.pdf https://oceanrep.geomar.de/id/eprint/24853/17/Figure_S1.tif https://oceanrep.geomar.de/id/eprint/24853/2/Figure_S2.tif https://oceanrep.geomar.de/id/eprint/24853/3/Figure_S3.tif Endres, S. , Galgani, L., Riebesell, U. , Schulz, K. G. and Engel, A. (2014) Stimulated Bacterial Growth under Elevated p Co2: Results from an Off-Shore Mesocosm Study. Open Access PLoS ONE, 9 (6). e99228. DOI 10.1371/journal.pone.0099228 <https://doi.org/10.1371/journal.pone.0099228>. doi:10.1371/journal.pone.0099228 |
op_rights |
cc_by info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1371/journal.pone.0099228 |
container_title |
PLoS ONE |
container_volume |
9 |
container_issue |
6 |
container_start_page |
e99228 |
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1766159405376602112 |