Cargando…
Predominance of Viable Spore-Forming Piezophilic Bacteria in High-Pressure Enrichment Cultures from ~1.5 to 2.4 km-Deep Coal-Bearing Sediments below the Ocean Floor
Phylogenetically diverse microorganisms have been observed in marine subsurface sediments down to ~2.5 km below the seafloor (kmbsf). However, very little is known about the pressure-adapted and/or pressure-loving microorganisms, the so called piezophiles, in the deep subseafloor biosphere, despite...
Autores principales: | , , , , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Frontiers Media S.A.
2017
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5292414/ https://www.ncbi.nlm.nih.gov/pubmed/28220112 http://dx.doi.org/10.3389/fmicb.2017.00137 |
_version_ | 1782504919295590400 |
---|---|
author | Fang, Jiasong Kato, Chiaki Runko, Gabriella M. Nogi, Yuichi Hori, Tomoyuki Li, Jiangtao Morono, Yuki Inagaki, Fumio |
author_facet | Fang, Jiasong Kato, Chiaki Runko, Gabriella M. Nogi, Yuichi Hori, Tomoyuki Li, Jiangtao Morono, Yuki Inagaki, Fumio |
author_sort | Fang, Jiasong |
collection | PubMed |
description | Phylogenetically diverse microorganisms have been observed in marine subsurface sediments down to ~2.5 km below the seafloor (kmbsf). However, very little is known about the pressure-adapted and/or pressure-loving microorganisms, the so called piezophiles, in the deep subseafloor biosphere, despite that pressure directly affects microbial physiology, metabolism, and biogeochemical processes of carbon and other elements in situ. In this study, we studied taxonomic compositions of microbial communities in high-pressure incubated sediment, obtained during the Integrated Ocean Drilling Program (IODP) Expedition 337 off the Shimokita Peninsula, Japan. Analysis of 16S rRNA gene-tagged sequences showed that members of spore-forming bacteria within Firmicutes and Actinobacteria were predominantly detected in all enrichment cultures from ~1.5 to 2.4 km-deep sediment samples, followed by members of Proteobacteria, Acidobacteria, and Bacteroidetes according to the sequence frequency. To further study the physiology of the deep subseafloor sedimentary piezophilic bacteria, we isolated and characterized two bacterial strains, 19R1-5 and 29R7-12, from 1.9 and 2.4 km-deep sediment samples, respectively. The isolates were both low G+C content, gram-positive, endospore-forming and facultative anaerobic piezophilic bacteria, closely related to Virgibacillus pantothenticus and Bacillus subtilis within the phylum Firmicutes, respectively. The optimal pressure and temperature conditions for growth were 20 MPa and 42°C for strain 19R1-5, and 10 MPa and 43°C for strain 29R7-12. Bacterial (endo)spores were observed in both the enrichment and pure cultures examined, suggesting that these piezophilic members were derived from microbial communities buried in the ~20 million-year-old coal-bearing sediments after the long-term survival as spores and that the deep biosphere may host more abundant gram-positive spore-forming bacteria and their spores than hitherto recognized. |
format | Online Article Text |
id | pubmed-5292414 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2017 |
publisher | Frontiers Media S.A. |
record_format | MEDLINE/PubMed |
spelling | pubmed-52924142017-02-20 Predominance of Viable Spore-Forming Piezophilic Bacteria in High-Pressure Enrichment Cultures from ~1.5 to 2.4 km-Deep Coal-Bearing Sediments below the Ocean Floor Fang, Jiasong Kato, Chiaki Runko, Gabriella M. Nogi, Yuichi Hori, Tomoyuki Li, Jiangtao Morono, Yuki Inagaki, Fumio Front Microbiol Microbiology Phylogenetically diverse microorganisms have been observed in marine subsurface sediments down to ~2.5 km below the seafloor (kmbsf). However, very little is known about the pressure-adapted and/or pressure-loving microorganisms, the so called piezophiles, in the deep subseafloor biosphere, despite that pressure directly affects microbial physiology, metabolism, and biogeochemical processes of carbon and other elements in situ. In this study, we studied taxonomic compositions of microbial communities in high-pressure incubated sediment, obtained during the Integrated Ocean Drilling Program (IODP) Expedition 337 off the Shimokita Peninsula, Japan. Analysis of 16S rRNA gene-tagged sequences showed that members of spore-forming bacteria within Firmicutes and Actinobacteria were predominantly detected in all enrichment cultures from ~1.5 to 2.4 km-deep sediment samples, followed by members of Proteobacteria, Acidobacteria, and Bacteroidetes according to the sequence frequency. To further study the physiology of the deep subseafloor sedimentary piezophilic bacteria, we isolated and characterized two bacterial strains, 19R1-5 and 29R7-12, from 1.9 and 2.4 km-deep sediment samples, respectively. The isolates were both low G+C content, gram-positive, endospore-forming and facultative anaerobic piezophilic bacteria, closely related to Virgibacillus pantothenticus and Bacillus subtilis within the phylum Firmicutes, respectively. The optimal pressure and temperature conditions for growth were 20 MPa and 42°C for strain 19R1-5, and 10 MPa and 43°C for strain 29R7-12. Bacterial (endo)spores were observed in both the enrichment and pure cultures examined, suggesting that these piezophilic members were derived from microbial communities buried in the ~20 million-year-old coal-bearing sediments after the long-term survival as spores and that the deep biosphere may host more abundant gram-positive spore-forming bacteria and their spores than hitherto recognized. Frontiers Media S.A. 2017-02-06 /pmc/articles/PMC5292414/ /pubmed/28220112 http://dx.doi.org/10.3389/fmicb.2017.00137 Text en Copyright © 2017 Fang, Kato, Runko, Nogi, Hori, Li, Morono and Inagaki. 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. |
spellingShingle | Microbiology Fang, Jiasong Kato, Chiaki Runko, Gabriella M. Nogi, Yuichi Hori, Tomoyuki Li, Jiangtao Morono, Yuki Inagaki, Fumio Predominance of Viable Spore-Forming Piezophilic Bacteria in High-Pressure Enrichment Cultures from ~1.5 to 2.4 km-Deep Coal-Bearing Sediments below the Ocean Floor |
title | Predominance of Viable Spore-Forming Piezophilic Bacteria in High-Pressure Enrichment Cultures from ~1.5 to 2.4 km-Deep Coal-Bearing Sediments below the Ocean Floor |
title_full | Predominance of Viable Spore-Forming Piezophilic Bacteria in High-Pressure Enrichment Cultures from ~1.5 to 2.4 km-Deep Coal-Bearing Sediments below the Ocean Floor |
title_fullStr | Predominance of Viable Spore-Forming Piezophilic Bacteria in High-Pressure Enrichment Cultures from ~1.5 to 2.4 km-Deep Coal-Bearing Sediments below the Ocean Floor |
title_full_unstemmed | Predominance of Viable Spore-Forming Piezophilic Bacteria in High-Pressure Enrichment Cultures from ~1.5 to 2.4 km-Deep Coal-Bearing Sediments below the Ocean Floor |
title_short | Predominance of Viable Spore-Forming Piezophilic Bacteria in High-Pressure Enrichment Cultures from ~1.5 to 2.4 km-Deep Coal-Bearing Sediments below the Ocean Floor |
title_sort | predominance of viable spore-forming piezophilic bacteria in high-pressure enrichment cultures from ~1.5 to 2.4 km-deep coal-bearing sediments below the ocean floor |
topic | Microbiology |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5292414/ https://www.ncbi.nlm.nih.gov/pubmed/28220112 http://dx.doi.org/10.3389/fmicb.2017.00137 |
work_keys_str_mv | AT fangjiasong predominanceofviablesporeformingpiezophilicbacteriainhighpressureenrichmentculturesfrom15to24kmdeepcoalbearingsedimentsbelowtheoceanfloor AT katochiaki predominanceofviablesporeformingpiezophilicbacteriainhighpressureenrichmentculturesfrom15to24kmdeepcoalbearingsedimentsbelowtheoceanfloor AT runkogabriellam predominanceofviablesporeformingpiezophilicbacteriainhighpressureenrichmentculturesfrom15to24kmdeepcoalbearingsedimentsbelowtheoceanfloor AT nogiyuichi predominanceofviablesporeformingpiezophilicbacteriainhighpressureenrichmentculturesfrom15to24kmdeepcoalbearingsedimentsbelowtheoceanfloor AT horitomoyuki predominanceofviablesporeformingpiezophilicbacteriainhighpressureenrichmentculturesfrom15to24kmdeepcoalbearingsedimentsbelowtheoceanfloor AT lijiangtao predominanceofviablesporeformingpiezophilicbacteriainhighpressureenrichmentculturesfrom15to24kmdeepcoalbearingsedimentsbelowtheoceanfloor AT moronoyuki predominanceofviablesporeformingpiezophilicbacteriainhighpressureenrichmentculturesfrom15to24kmdeepcoalbearingsedimentsbelowtheoceanfloor AT inagakifumio predominanceofviablesporeformingpiezophilicbacteriainhighpressureenrichmentculturesfrom15to24kmdeepcoalbearingsedimentsbelowtheoceanfloor |