Polycyclic Aromatic Hydrocarbon Degradation in the Sea-Surface Microlayer at Coastal Antarctica
As much as 400 Tg of carbon from airborne semivolatile aromatic hydrocarbons is deposited to the oceans every year, the largest identified source of anthropogenic organic carbon to the ocean. Microbial degradation is a key sink of these pollutants in surface waters, but has received little attention...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2022-07-01
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| Series: | Frontiers in Microbiology |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fmicb.2022.907265/full |
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| author | Alícia Martinez-Varela Gemma Casas Naiara Berrojalbiz Benjamin Piña Jordi Dachs Maria Vila-Costa |
| author_facet | Alícia Martinez-Varela Gemma Casas Naiara Berrojalbiz Benjamin Piña Jordi Dachs Maria Vila-Costa |
| author_sort | Alícia Martinez-Varela |
| collection | DOAJ |
| description | As much as 400 Tg of carbon from airborne semivolatile aromatic hydrocarbons is deposited to the oceans every year, the largest identified source of anthropogenic organic carbon to the ocean. Microbial degradation is a key sink of these pollutants in surface waters, but has received little attention in polar environments. We have challenged Antarctic microbial communities from the sea-surface microlayer (SML) and the subsurface layer (SSL) with polycyclic aromatic hydrocarbons (PAHs) at environmentally relevant concentrations. PAH degradation rates and the microbial responses at both taxonomical and functional levels were assessed. Evidence for faster removal rates was observed in the SML, with rates 2.6-fold higher than in the SSL. In the SML, the highest removal rates were observed for the more hydrophobic and particle-bound PAHs. After 24 h of PAHs exposure, particle-associated bacteria in the SML showed the highest number of significant changes in their composition. These included significant enrichments of several hydrocarbonoclastic bacteria, especially the fast-growing genera Pseudoalteromonas, which increased their relative abundances by eightfold. Simultaneous metatranscriptomic analysis showed that the free-living fraction of SML was the most active fraction, especially for members of the order Alteromonadales, which includes Pseudoalteromonas. Their key role in PAHs biodegradation in polar environments should be elucidated in further studies. This study highlights the relevant role of bacterial populations inhabiting the sea-surface microlayer, especially the particle-associated habitat, as relevant bioreactors for the removal of aromatic hydrocarbons in the oceans. |
| first_indexed | 2024-12-11T01:55:20Z |
| format | Article |
| id | doaj.art-0834e92a1ea5457a8f48d684b69f5854 |
| institution | Directory Open Access Journal |
| issn | 1664-302X |
| language | English |
| last_indexed | 2024-12-11T01:55:20Z |
| publishDate | 2022-07-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Microbiology |
| spelling | doaj.art-0834e92a1ea5457a8f48d684b69f58542022-12-22T01:24:38ZengFrontiers Media S.A.Frontiers in Microbiology1664-302X2022-07-011310.3389/fmicb.2022.907265907265Polycyclic Aromatic Hydrocarbon Degradation in the Sea-Surface Microlayer at Coastal AntarcticaAlícia Martinez-VarelaGemma CasasNaiara BerrojalbizBenjamin PiñaJordi DachsMaria Vila-CostaAs much as 400 Tg of carbon from airborne semivolatile aromatic hydrocarbons is deposited to the oceans every year, the largest identified source of anthropogenic organic carbon to the ocean. Microbial degradation is a key sink of these pollutants in surface waters, but has received little attention in polar environments. We have challenged Antarctic microbial communities from the sea-surface microlayer (SML) and the subsurface layer (SSL) with polycyclic aromatic hydrocarbons (PAHs) at environmentally relevant concentrations. PAH degradation rates and the microbial responses at both taxonomical and functional levels were assessed. Evidence for faster removal rates was observed in the SML, with rates 2.6-fold higher than in the SSL. In the SML, the highest removal rates were observed for the more hydrophobic and particle-bound PAHs. After 24 h of PAHs exposure, particle-associated bacteria in the SML showed the highest number of significant changes in their composition. These included significant enrichments of several hydrocarbonoclastic bacteria, especially the fast-growing genera Pseudoalteromonas, which increased their relative abundances by eightfold. Simultaneous metatranscriptomic analysis showed that the free-living fraction of SML was the most active fraction, especially for members of the order Alteromonadales, which includes Pseudoalteromonas. Their key role in PAHs biodegradation in polar environments should be elucidated in further studies. This study highlights the relevant role of bacterial populations inhabiting the sea-surface microlayer, especially the particle-associated habitat, as relevant bioreactors for the removal of aromatic hydrocarbons in the oceans.https://www.frontiersin.org/articles/10.3389/fmicb.2022.907265/fullPAHsea-surface microlayerhydrocarbonoclastic bacteriaAlteromonadalesPAH biodegradationcoastal Antarctica |
| spellingShingle | Alícia Martinez-Varela Gemma Casas Naiara Berrojalbiz Benjamin Piña Jordi Dachs Maria Vila-Costa Polycyclic Aromatic Hydrocarbon Degradation in the Sea-Surface Microlayer at Coastal Antarctica Frontiers in Microbiology PAH sea-surface microlayer hydrocarbonoclastic bacteria Alteromonadales PAH biodegradation coastal Antarctica |
| title | Polycyclic Aromatic Hydrocarbon Degradation in the Sea-Surface Microlayer at Coastal Antarctica |
| title_full | Polycyclic Aromatic Hydrocarbon Degradation in the Sea-Surface Microlayer at Coastal Antarctica |
| title_fullStr | Polycyclic Aromatic Hydrocarbon Degradation in the Sea-Surface Microlayer at Coastal Antarctica |
| title_full_unstemmed | Polycyclic Aromatic Hydrocarbon Degradation in the Sea-Surface Microlayer at Coastal Antarctica |
| title_short | Polycyclic Aromatic Hydrocarbon Degradation in the Sea-Surface Microlayer at Coastal Antarctica |
| title_sort | polycyclic aromatic hydrocarbon degradation in the sea surface microlayer at coastal antarctica |
| topic | PAH sea-surface microlayer hydrocarbonoclastic bacteria Alteromonadales PAH biodegradation coastal Antarctica |
| url | https://www.frontiersin.org/articles/10.3389/fmicb.2022.907265/full |
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