| Title | Contribution of bicarbonate assimilation to carbon pool dynamics in the deep Mediterranean Sea and cultivation of actively nitrifying and CO2-fixing bathypelagic prokaryotic consortia |
| Abstract | Covering two-thirds of our planet, the global deep ocean plays a central role in supporting life on Earth. Among other processes, this biggest ecosystem buffers the rise of atmospheric CO. Despite carbon sequestration in the deep ocean has been known for a long time, microbial activity in the meso- and bathypelagic realm via the "assimilation of bicarbonate in the dark" (ABD) has only recently been described in more details. Based on recent findings, this process seems primarily the result of chemosynthetic and anaplerotic reactions driven by different groups of deep-sea prokaryoplankton. We quantified bicarbonate assimilation in relation to total prokaryotic abundance, prokaryotic heterotrophic production and respiration in the meso- and bathypelagic Mediterranean Sea. The measured ABD values, ranging from 133 to 370 ?g C m d, were among the highest ones reported worldwide for similar depths, likely due to the elevated temperature of the deep Mediterranean Sea (13-14°C also at abyssal depths). Integrated over the dark water column (>=200 m depth), bicarbonate assimilation in the deep-sea ranged from 396 to 873 mg C m d. This quantity of produced de novo organic carbon amounts to about 85-424% of the phytoplankton primary production and covers up to 62% of deep-sea prokaryotic total carbon demand. Hence, the ABD process in the meso- and bathypelagic Mediterranean Sea might substantially contribute to the inorganic and organic pool and significantly sustain the deep-sea microbial food web. To elucidate the ABD key-players, we established three actively nitrifying and CO-fixing prokaryotic enrichments. Consortia were characterized by the co-occurrence of chemolithoautotrophic Thaumarchaeota and chemoheterotrophic proteobacteria. One of the enrichments, originated from Ionian bathypelagic waters (3,000 m depth) and supplemented with low concentrations of ammonia, was dominated by the Thaumarchaeota "low-ammonia-concentration" deep-sea ecotype, an enigmatic and ecologically important group of organisms, uncultured until this study. |
| Source | Frontiers in microbiology 9 (JAN) |
| Keywords | Ammonium-oxidizing ThaumarchaeotaAnaplerotic reactionsDark bicarbonate assimilationDeep-sea microbial communityMediterranean sea |
| Journal | Frontiers in microbiology |
| Editor | Frontiers Research Foundation,, Lausanne, Svizzera |
| Year | 2018 |
| Type | Articolo in rivista |
| DOI | 10.3389/fmicb.2018.00003 |
| Authors | La Cono, Violetta; Ruggeri, Gioachino; Azzaro, Maurizio; Crisafi, Francesca; Decembrini, Franco; Denaro, Renata; La Spada, Gina; Maimone, Giovanna; Monticelli, Luis S.; Smedile, Francesco; Giuliano, Laura; Yakimov, Michail M. |
| Text | 445694 2018 10.3389/fmicb.2018.00003 Scopus 2 s2.0 85040827677 Ammonium oxidizing Thaumarchaeota Anaplerotic reactions Dark bicarbonate assimilation Deep sea microbial community Mediterranean sea Contribution of bicarbonate assimilation to carbon pool dynamics in the deep Mediterranean Sea and cultivation of actively nitrifying and CO2 fixing bathypelagic prokaryotic consortia La Cono, Violetta; Ruggeri, Gioachino; Azzaro, Maurizio; Crisafi, Francesca; Decembrini, Franco; Denaro, Renata; La Spada, Gina; Maimone, Giovanna; Monticelli, Luis S.; Smedile, Francesco; Giuliano, Laura; Yakimov, Michail M. Rutgers University New Brunswick; Istituto per l Ambiente Marino Costiero del Consiglio Nazionale delle Ricerche IAMC CNR ; Immanuel Kant Baltic Federal University; Mediterranean Science Commission CIESM Covering two thirds of our planet, the global deep ocean plays a central role in supporting life on Earth. Among other processes, this biggest ecosystem buffers the rise of atmospheric CO. Despite carbon sequestration in the deep ocean has been known for a long time, microbial activity in the meso and bathypelagic realm via the assimilation of bicarbonate in the dark ABD has only recently been described in more details. Based on recent findings, this process seems primarily the result of chemosynthetic and anaplerotic reactions driven by different groups of deep sea prokaryoplankton. We quantified bicarbonate assimilation in relation to total prokaryotic abundance, prokaryotic heterotrophic production and respiration in the meso and bathypelagic Mediterranean Sea. The measured ABD values, ranging from 133 to 370 g C m d, were among the highest ones reported worldwide for similar depths, likely due to the elevated temperature of the deep Mediterranean Sea 13 14°C also at abyssal depths . Integrated over the dark water column >=200 m depth , bicarbonate assimilation in the deep sea ranged from 396 to 873 mg C m d. This quantity of produced de novo organic carbon amounts to about 85 424% of the phytoplankton primary production and covers up to 62% of deep sea prokaryotic total carbon demand. Hence, the ABD process in the meso and bathypelagic Mediterranean Sea might substantially contribute to the inorganic and organic pool and significantly sustain the deep sea microbial food web. To elucidate the ABD key players, we established three actively nitrifying and CO fixing prokaryotic enrichments. Consortia were characterized by the co occurrence of chemolithoautotrophic Thaumarchaeota and chemoheterotrophic proteobacteria. One of the enrichments, originated from Ionian bathypelagic waters 3,000 m depth and supplemented with low concentrations of ammonia, was dominated by the Thaumarchaeota low ammonia concentration deep sea ecotype, an enigmatic and ecologically important group of organisms, uncultured until this study. 9 Published version http //www.scopus.com/record/display.url eid=2 s2.0 85040827677 origin=inward La Cono et al., 2018 Article fmicb 09 00003.pdf Articolo in rivista Frontiers Research Foundation, 1664 302X Frontiers in microbiology Frontiers in microbiology Front. microbiol. Frontiers in microbiology franco.decembrini DECEMBRINI FRANCO maurizio.azzaro AZZARO MAURIZIO mikhail.iakimov IAKIMOV MIKHAIL renata.denaro DENARO RENATA violetta.lacono LA CONO VIOLETTA francesco.smedile SMEDILE FRANCESCO francesca.crisafi CRISAFI FRANCESCA giovanna.maimone MAIMONE GIOVANNA INMARE Industrial Applications of Marine Enzymes Innovative screening and expression platforms to discover and use the functional protein diversity from the sea DTA.AD008.001.053 Progetto Bandiera Ritmare IAS |
