Unexpected scarcity of ANME archaea in hydrocarbon seeps within Monterey Bay
<p>Marine hydrocarbon seeps typically harbor a relatively predictable microbiome, including anaerobic methanotrophic (ANME) archaea. Here, we sampled two cold seeps in Monterey Bay, CA – Clam Field and Extrovert Cliff – which have been known for decades but never characterized microbiologicall...
Saved in:
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2025-01-01
|
| Series: | Biogeosciences |
| Online Access: | https://bg.copernicus.org/articles/22/385/2025/bg-22-385-2025.pdf |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1832591478512156672 |
|---|---|
| author | A. C. Semler A. E. Dekas |
| author_facet | A. C. Semler A. E. Dekas |
| author_sort | A. C. Semler |
| collection | DOAJ |
| description | <p>Marine hydrocarbon seeps typically harbor a relatively predictable microbiome, including anaerobic methanotrophic (ANME) archaea. Here, we sampled two cold seeps in Monterey Bay, CA – Clam Field and Extrovert Cliff – which have been known for decades but never characterized microbiologically. Many aspects of these seeps were typical of seeps worldwide, including elevated methane and sulfide concentrations, <span class="inline-formula"><sup>13</sup></span>C-depleted dissolved inorganic carbon, and the presence of characteristic macrofauna. However, we observed atypical microbial communities: extremely few ANME sequences were detected in either 16S rRNA or <i>mcrA</i> gene surveys at Clam Field (<span class="inline-formula"><</span> 0.1 % of total community reads), even after 6 months of incubation with methane in the laboratory, and only slightly more ANME sequences were recovered from Extrovert Cliff (<span class="inline-formula"><</span> 0.3 % of total community reads). At Clam Field, a lack of ANME <i>mcrA</i> transcription, a lack of methane-dependent sulfate reduction, and a linear porewater methane profile were consistent with low or absent methanotrophy. Although the reason for the scarcity of ANME archaea is still unclear, we postulate that non-methane hydrocarbon release excludes anaerobic methanotrophs directly or indirectly (e.g., through competitive interactions with hydrocarbon-degrading bacteria). Our findings highlight the potential for hydrocarbon seeps without this critical biofilter and therefore greater methane emissions from sediments.</p> |
| format | Article |
| id | doaj-art-d75020d18a534677ac96d8a133cde8de |
| institution | Kabale University |
| issn | 1726-4170 1726-4189 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Biogeosciences |
| spelling | doaj-art-d75020d18a534677ac96d8a133cde8de2025-01-22T10:58:16ZengCopernicus PublicationsBiogeosciences1726-41701726-41892025-01-012238540310.5194/bg-22-385-2025Unexpected scarcity of ANME archaea in hydrocarbon seeps within Monterey BayA. C. Semler0A. E. Dekas1Department of Earth System Science, Stanford University, Stanford, CA 94305, USADepartment of Earth System Science, Stanford University, Stanford, CA 94305, USA<p>Marine hydrocarbon seeps typically harbor a relatively predictable microbiome, including anaerobic methanotrophic (ANME) archaea. Here, we sampled two cold seeps in Monterey Bay, CA – Clam Field and Extrovert Cliff – which have been known for decades but never characterized microbiologically. Many aspects of these seeps were typical of seeps worldwide, including elevated methane and sulfide concentrations, <span class="inline-formula"><sup>13</sup></span>C-depleted dissolved inorganic carbon, and the presence of characteristic macrofauna. However, we observed atypical microbial communities: extremely few ANME sequences were detected in either 16S rRNA or <i>mcrA</i> gene surveys at Clam Field (<span class="inline-formula"><</span> 0.1 % of total community reads), even after 6 months of incubation with methane in the laboratory, and only slightly more ANME sequences were recovered from Extrovert Cliff (<span class="inline-formula"><</span> 0.3 % of total community reads). At Clam Field, a lack of ANME <i>mcrA</i> transcription, a lack of methane-dependent sulfate reduction, and a linear porewater methane profile were consistent with low or absent methanotrophy. Although the reason for the scarcity of ANME archaea is still unclear, we postulate that non-methane hydrocarbon release excludes anaerobic methanotrophs directly or indirectly (e.g., through competitive interactions with hydrocarbon-degrading bacteria). Our findings highlight the potential for hydrocarbon seeps without this critical biofilter and therefore greater methane emissions from sediments.</p>https://bg.copernicus.org/articles/22/385/2025/bg-22-385-2025.pdf |
| spellingShingle | A. C. Semler A. E. Dekas Unexpected scarcity of ANME archaea in hydrocarbon seeps within Monterey Bay Biogeosciences |
| title | Unexpected scarcity of ANME archaea in hydrocarbon seeps within Monterey Bay |
| title_full | Unexpected scarcity of ANME archaea in hydrocarbon seeps within Monterey Bay |
| title_fullStr | Unexpected scarcity of ANME archaea in hydrocarbon seeps within Monterey Bay |
| title_full_unstemmed | Unexpected scarcity of ANME archaea in hydrocarbon seeps within Monterey Bay |
| title_short | Unexpected scarcity of ANME archaea in hydrocarbon seeps within Monterey Bay |
| title_sort | unexpected scarcity of anme archaea in hydrocarbon seeps within monterey bay |
| url | https://bg.copernicus.org/articles/22/385/2025/bg-22-385-2025.pdf |
| work_keys_str_mv | AT acsemler unexpectedscarcityofanmearchaeainhydrocarbonseepswithinmontereybay AT aedekas unexpectedscarcityofanmearchaeainhydrocarbonseepswithinmontereybay |