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Dong C, Chen Q, Chen J, Dong L, Chen Y, Jiao N, Tang K. Investigating organic sulfur in estuarine and offshore environments: A combined field and cultivation approach. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:171599. [PMID: 38490410 DOI: 10.1016/j.scitotenv.2024.171599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 03/06/2024] [Accepted: 03/07/2024] [Indexed: 03/17/2024]
Abstract
Estuarine-offshore sediments accumulate substantial particulate organic matter, containing organic sulfur as a key component. However, the distribution and sources of organic sulfur in such environments remain poorly understood. This study investigated organic sulfur in the Yangtze River Estuary and adjacent East China Sea. Dissolved organic sulfur varied from 0.65 to 1.99 μmol/L (molar S:C 0.006-0.018), while particulate organic sulfur ranged from 0.42 to 2.69 μmol/L (molar S:C 0.007-0.082). Sedimentary organic sulfur exhibited a similar molar S:C ratio (0.014-0.071) to particulate organic sulfur in bottom water, implying that particulate matter deposition is a potential source. Furthermore, sediments exposed to frequent hypoxia harbored significantly higher organic sulfur and S:C values compared to non-hypoxic areas. Laboratory incubation experiments revealed the underlying mechanism: sustained activity of sulfate-reducing bacteria in hypoxic sediments led to a substantial increase in sedimentary organic sulfur (from 15 to 53 μmol/g) within 600 days. This microbially driven sulfurization rendered over 90 % of the organic sulfur resistant to acid hydrolysis. Therefore, this study demonstrates that, alongside particle deposition, microbial sulfurization significantly contributes to organic sulfur enrichment and likely promotes organic matter preservation in estuarine-offshore sediments, particularly under hypoxic conditions. This finding advances our understanding of organic sulfur sources in these vital ecosystems.
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Affiliation(s)
- Changjie Dong
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China
| | - Quanrui Chen
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China
| | - Junhui Chen
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China
| | - Liang Dong
- School of Oceanography, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yaojin Chen
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China
| | - Nianzhi Jiao
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China.
| | - Kai Tang
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China.
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2
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She Z, Wang J, Pan X, Ma D, Gao Y, Wang S, Chuai X, Mu Y, Yue Z. Multi-omics insights into biogeochemical responses to organic matter addition in an acidic pit lake: Implications for bioremediation. WATER RESEARCH 2024; 254:121404. [PMID: 38442608 DOI: 10.1016/j.watres.2024.121404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 01/30/2024] [Accepted: 02/29/2024] [Indexed: 03/07/2024]
Abstract
Acidic pit lakes (APLs) emerge as reservoirs of acid mine drainage in flooded open-pit mines, representing extreme ecosystems and environmental challenges worldwide. The bioremediation of these oligotrophic waters necessitates the addition of organic matter, but the biogeochemical response of APLs to exogenous organic matter remains inadequately comprehended. This study delves into the biogeochemical impacts and remediation effects of digestate-derived organic matter within an APL, employing a multi-omics approach encompassing geochemical analyses, amplicon and metagenome sequencing, and ultra-high resolution mass spectrometry. The results indicated that digestate addition first stimulated fungal proliferation, particularly Ascomycetes and Basidiomycetes, which generated organic acids through lignocellulosic hydrolysis and fermentation. These simple compounds further supported heterotrophic growth, including Acidiphilium, Acidithrix, and Clostridium, thereby facilitating nitrate, iron, and sulfate reduction linked with acidity consumption. Nutrients derived from digestate also promoted the macroscopic development of acidophilic algae. Notably, the increased sulfate reduction-related genes primarily originated from assimilatory metabolism, thus connecting sulfate decrease to organosulfur increase. Assimilatory and dissimilatory sulfate reduction collectively contributed to sulfate removal and metal fixation. These findings yield multi-omics insights into APL biogeochemical responses to organic matter addition, enhancing the understanding of carbon-centered biogeochemical cycling in extreme ecosystems and guiding organic amendment-based bioremediation in oligotrophic polluted environments.
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Affiliation(s)
- Zhixiang She
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui 230009, China; Anhui Engineering Research Center of Industrial Wastewater Treatment and Resource Recovery, Hefei University of Technology, Hefei, Anhui 230009, China; Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei, Anhui 230009, China
| | - Jin Wang
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui 230009, China; Anhui Engineering Research Center of Industrial Wastewater Treatment and Resource Recovery, Hefei University of Technology, Hefei, Anhui 230009, China; Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei, Anhui 230009, China.
| | - Xin Pan
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui 230009, China; Anhui Engineering Research Center of Industrial Wastewater Treatment and Resource Recovery, Hefei University of Technology, Hefei, Anhui 230009, China; Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei, Anhui 230009, China
| | - Ding Ma
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui 230009, China; Anhui Engineering Research Center of Industrial Wastewater Treatment and Resource Recovery, Hefei University of Technology, Hefei, Anhui 230009, China; Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei, Anhui 230009, China
| | - Yijun Gao
- Luohe Mining Company Ltd, Anhui Maanshan Iron and Steel Mining Resources Group, Hefei, Anhui 230009, China
| | - Shaoping Wang
- Nanshan Mining Company Ltd, Anhui Maanshan Iron and Steel Mining Resources Group, Ma'anshan, Anhui 243000, China
| | - Xin Chuai
- Nanshan Mining Company Ltd, Anhui Maanshan Iron and Steel Mining Resources Group, Ma'anshan, Anhui 243000, China
| | - Yang Mu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Zhengbo Yue
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, Anhui 230009, China; Anhui Engineering Research Center of Industrial Wastewater Treatment and Resource Recovery, Hefei University of Technology, Hefei, Anhui 230009, China; Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei, Anhui 230009, China.
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3
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Ren M, Zhuang Q, He X, Liu W, Guo C, Ye H, Reinfelder JR, Ma C, Li J, Dang Z. Speciation and Possible Origins of Organosulfur Compounds in Rice Paddy Soils Affected by Acid Mine Drainage. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:7357-7366. [PMID: 38568220 DOI: 10.1021/acs.est.3c09622] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/01/2024]
Abstract
Although sulfur cycling in acid mine drainage (AMD)-contaminated rice paddy soils is critical to understanding and mitigating the environmental consequences of AMD, potential sources and transformations of organosulfur compounds in such soils are poorly understood. We used sulfur K-edge X-ray absorption near edge structure (XANES) spectroscopy to quantify organosulfur compounds in paddy soils from five AMD-contaminated sites and one AMD-uncontaminated reference site near the Dabaoshan sulfide mining area in South China. We also determined the sulfur stable isotope compositions of water-soluble sulfate (δ34SWS), adsorbed sulfate (δ34SAS), fulvic acid sulfur (δ34SFAS), and humic acid sulfur (δ34SHAS) in these samples. Organosulfate was the dominant functional group in humic acid sulfur (HAS) in both AMD-contaminated (46%) and AMD-uncontaminated paddy soils (42%). Thiol/organic monosulfide contributed a significantly lower proportion of HAS in AMD-contaminated paddy soils (8%) compared to that in AMD-uncontaminated paddy soils (21%). Within contaminated soils, the concentration of thiol/organic monosulfide was positively correlated with cation exchange capacity (CEC), moisture content (MC), and total Fe (TFe). δ34SFAS ranged from -6.3 to 2.7‰, similar to δ34SWS (-6.9 to 8.9‰), indicating that fulvic acid sulfur (FAS) was mainly derived from biogenic S-bearing organic compounds produced by assimilatory sulfate reduction. δ34SHAS (-11.0 to -1.6‰) were more negative compared to δ34SWS, indicating that dissimilatory sulfate reduction and abiotic sulfurization of organic matter were the main processes in the formation of HAS.
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Affiliation(s)
- Meihui Ren
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China
| | - Qinglin Zhuang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China
| | - Xiaoshuang He
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China
| | - Wenxuan Liu
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China
| | - Chuling Guo
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou 510006, PR China
| | - Han Ye
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China
| | - John R Reinfelder
- Department of Environmental Sciences, Rutgers University, New Brunswick, New Jersey 08901, United States
| | - Chengyan Ma
- Institute of High Energy Physics, Chinese Academy of Science, Beijing Synchrotron Radiation Facility, Beijing 100049, China
| | - Jianmin Li
- Institute of High Energy Physics, Chinese Academy of Science, Beijing Synchrotron Radiation Facility, Beijing 100049, China
| | - Zhi Dang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou 510006, PR China
- China Guangdong Provincial Key Lab of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou 510006, China
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4
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Siebers R, Schultz D, Farza MS, Brauer A, Zühlke D, Mücke PA, Wang F, Bernhardt J, Teeling H, Becher D, Riedel K, Kirstein IV, Wiltshire KH, Hoff KJ, Schweder T, Urich T, Bengtsson MM. Marine particle microbiomes during a spring diatom bloom contain active sulfate-reducing bacteria. FEMS Microbiol Ecol 2024; 100:fiae037. [PMID: 38490736 PMCID: PMC11008741 DOI: 10.1093/femsec/fiae037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 02/08/2024] [Accepted: 03/14/2024] [Indexed: 03/17/2024] Open
Abstract
Phytoplankton blooms fuel marine food webs with labile dissolved carbon and also lead to the formation of particulate organic matter composed of living and dead algal cells. These particles contribute to carbon sequestration and are sites of intense algal-bacterial interactions, providing diverse niches for microbes to thrive. We analyzed 16S and 18S ribosomal RNA gene amplicon sequences obtained from 51 time points and metaproteomes from 3 time points during a spring phytoplankton bloom in a shallow location (6-10 m depth) in the North Sea. Particulate fractions larger than 10 µm diameter were collected at near daily intervals between early March and late May in 2018. Network analysis identified two major modules representing bacteria co-occurring with diatoms and with dinoflagellates, respectively. The diatom network module included known sulfate-reducing Desulfobacterota as well as potentially sulfur-oxidizing Ectothiorhodospiraceae. Metaproteome analyses confirmed presence of key enzymes involved in dissimilatory sulfate reduction, a process known to occur in sinking particles at greater depths and in sediments. Our results indicate the presence of sufficiently anoxic niches in the particle fraction of an active phytoplankton bloom to sustain sulfate reduction, and an important role of benthic-pelagic coupling for microbiomes in shallow environments. Our findings may have implications for the understanding of algal-bacterial interactions and carbon export during blooms in shallow-water coastal areas.
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Affiliation(s)
- Robin Siebers
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Doreen Schultz
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Mohamed S Farza
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Anne Brauer
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Daniela Zühlke
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Pierre A Mücke
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Fengqing Wang
- Max Planck Institute for Marine Microbiology, 28359 Bremen, Germany
| | - Jörg Bernhardt
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Hanno Teeling
- Max Planck Institute for Marine Microbiology, 28359 Bremen, Germany
| | - Dörte Becher
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
| | - Katharina Riedel
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
- Institute of Marine Biotechnology, 17489 Greifswald, Germany
| | - Inga V Kirstein
- Alfred-Wegener-Institute Helmholtz Centre for Polar and Marine Research, Biologische Anstalt Helgoland, 27498 Helgoland, Germany
| | - Karen H Wiltshire
- Alfred-Wegener-Institute Helmholtz Centre for Polar and Marine Research, Biologische Anstalt Helgoland, 27498 Helgoland, Germany
| | - Katharina J Hoff
- Institute of Mathematics and Computer Science, University of Greifswald, 17489 Greifswald, Germany
| | - Thomas Schweder
- Institute of Marine Biotechnology, 17489 Greifswald, Germany
- Institute of Pharmacy, University of Greifswald, 17489 Greifswald, Germany
| | - Tim Urich
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
- Institute of Marine Biotechnology, 17489 Greifswald, Germany
| | - Mia M Bengtsson
- Institute of Microbiology, University of Greifswald, Greifswald, Germany
- Institute of Marine Biotechnology, 17489 Greifswald, Germany
- Alfred-Wegener-Institute Helmholtz Centre for Polar and Marine Research, Biologische Anstalt Helgoland, 27498 Helgoland, Germany
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5
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Xue J, Deng Y, Pi K, Fu QL, Du Y, Xu Y, Yuan X, Fan R, Xie X, Shi J, Wang Y. Enrichment of Geogenic Organoiodine Compounds in Alluvial-Lacustrine Aquifers: Molecular Constraints by Organic Matter. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:5932-5941. [PMID: 38502530 DOI: 10.1021/acs.est.3c07314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
Organoiodine compounds (OICs) are the dominant iodine species in groundwater systems. However, molecular mechanisms underlying the geochemical formation of geogenic OICs-contaminated groundwater remain unclear. Based upon multitarget field monitoring in combination with ultrahigh-resolution molecular characterization of organic components for alluvial-lacustrine aquifers, we identified a total of 939 OICs in groundwater under reducing and circumneutral pH conditions. In comparison to those in water-soluble organic matter (WSOM) in sediments, the OICs in dissolved organic matter (DOM) in groundwater typically contain fewer polycyclic aromatics and polyphenol compounds but more highly unsaturated compounds. Consequently, there were two major sources of geogenic OICs in groundwater: the migration of the OICs from aquifer sediments and abiotic reduction of iodate coupled with DOM iodination under reducing conditions. DOM iodination occurs primarily through the incorporation of reactive iodine that is generated by iodate reduction into highly unsaturated compounds, preferably containing hydrophilic functional groups as binding sites. It leads to elevation of the concentration of the OICs up to 183 μg/L in groundwater. This research provides new insights into the constraints of DOM molecular composition on the mobilization and enrichment of OICs in alluvial-lacustrine aquifers and thus improves our understanding of the genesis of geogenic iodine-contaminated groundwater systems.
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Affiliation(s)
- Jiangkai Xue
- Key Laboratory of Groundwater Quality and Health, China University of Geosciences, Ministry of Education, Wuhan 430078, China
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, China
| | - Yamin Deng
- Key Laboratory of Groundwater Quality and Health, China University of Geosciences, Ministry of Education, Wuhan 430078, China
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, China
| | - Kunfu Pi
- Key Laboratory of Groundwater Quality and Health, China University of Geosciences, Ministry of Education, Wuhan 430078, China
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, China
| | - Qing-Long Fu
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, China
| | - Yao Du
- Key Laboratory of Groundwater Quality and Health, China University of Geosciences, Ministry of Education, Wuhan 430078, China
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, China
| | - Yuxiao Xu
- Key Laboratory of Groundwater Quality and Health, China University of Geosciences, Ministry of Education, Wuhan 430078, China
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, China
| | - Xiaofang Yuan
- Key Laboratory of Groundwater Quality and Health, China University of Geosciences, Ministry of Education, Wuhan 430078, China
| | - Ruiyu Fan
- Key Laboratory of Groundwater Quality and Health, China University of Geosciences, Ministry of Education, Wuhan 430078, China
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, China
| | - Xianjun Xie
- Key Laboratory of Groundwater Quality and Health, China University of Geosciences, Ministry of Education, Wuhan 430078, China
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, China
| | - Jianbo Shi
- Key Laboratory of Groundwater Quality and Health, China University of Geosciences, Ministry of Education, Wuhan 430078, China
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, China
| | - Yanxin Wang
- Key Laboratory of Groundwater Quality and Health, China University of Geosciences, Ministry of Education, Wuhan 430078, China
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, China
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Kim J, Soerensen AL, Jeong H, Jeong S, Kim E, Lee YM, Jin YK, Rhee TS, Hong JK, Han S. Cross-shelf processes of terrigenous organic matter drive mercury speciation on the east siberian shelf in the Arctic Ocean. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 343:123270. [PMID: 38163627 DOI: 10.1016/j.envpol.2023.123270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 12/15/2023] [Accepted: 12/28/2023] [Indexed: 01/03/2024]
Abstract
The cross-shelf distributions of total mercury (THg), methylmercury (MeHg) and organic and inorganic matter, as well as the presence of the hgcA gene were investigated on the East Siberian Shelf (ESS) to understand the processes underlying the speciation of sedimentary Hg. Samples were collected from 12 stations grouped into four zones based on water depth: inner shelf (5 stations), mid-shelf (3 stations), outer shelf (2 stations), and slope (2 stations). The THg concentration in the surface sediment increased from the inner shelf (0.25 ± 0.023 nmol g-1) toward the slope (0.52 nmol g-1), and, when normalized to total organic carbon content, the THg showed a positive correlation with the clay-to-sand ratio (r2 = 0.48, p = 0.012) and degree of chemical weathering (r2 = 0.79, p = 0.0001). The highest MeHg concentrations (3.0 ± 1.8 pmol g-1), as well as peaks in the S/C ratio (0.012 ± 0.002) of sediment-leached organic matter, were found on the mid-shelf, suggesting that the activities of sulfate reducers control the net Hg(II) methylation rates in the sediment. This was supported by results from a principal component analysis (PCA) performed with Hg species concentrations and sediment-leached organic matter compositions. The site-specific variation in MeHg showed the highest similarity with that of CHONS compounds in the PCA, where Deltaproteobacteria were projected to be putative Hg(II) methylators in the gene analysis. In summary, the hydrodynamic sorting of lithogenic particles appears to govern the cross-shelf distribution of THg, and in situ methylation is considered a major source of MeHg in the ESS sediment.
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Affiliation(s)
- Jihee Kim
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
| | - Anne L Soerensen
- Department of Environmental Research and Monitoring, Swedish Museum of Natural History, Stockholm, Sweden
| | - Hakwon Jeong
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
| | - Seorin Jeong
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
| | - Eunsuk Kim
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
| | - Yung Mi Lee
- Korea Polar Research Institute, Incheon, Republic of Korea
| | - Young Keun Jin
- Korea Polar Research Institute, Incheon, Republic of Korea
| | - Tae Siek Rhee
- Korea Polar Research Institute, Incheon, Republic of Korea
| | - Jong Kuk Hong
- Korea Polar Research Institute, Incheon, Republic of Korea
| | - Seunghee Han
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea.
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7
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Cram JA, Hollins A, McCarty AJ, Martinez G, Cui M, Gomes ML, Fuchsman CA. Microbial diversity and abundance vary along salinity, oxygen, and particle size gradients in the Chesapeake Bay. Environ Microbiol 2024; 26:e16557. [PMID: 38173306 DOI: 10.1111/1462-2920.16557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 11/27/2023] [Indexed: 01/05/2024]
Abstract
Marine snow and other particles are abundant in estuaries, where they drive biogeochemical transformations and elemental transport. Particles range in size, thereby providing a corresponding gradient of habitats for marine microorganisms. We used standard normalized amplicon sequencing, verified with microscopy, to characterize taxon-specific microbial abundances, (cells per litre of water and per milligrams of particles), across six particle size classes, ranging from 0.2 to 500 μm, along the main stem of the Chesapeake Bay estuary. Microbial communities varied in salinity, oxygen concentrations, and particle size. Many taxonomic groups were most densely packed on large particles (in cells/mg particles), yet were primarily associated with the smallest particle size class, because small particles made up a substantially larger portion of total particle mass. However, organisms potentially involved in methanotrophy, nitrite oxidation, and sulphate reduction were found primarily on intermediately sized (5-180 μm) particles, where species richness was also highest. All abundant ostensibly free-living organisms, including SAR11 and Synecococcus, appeared on particles, albeit at lower abundance than in the free-living fraction, suggesting that aggregation processes may incorporate them into particles. Our approach opens the door to a more quantitative understanding of the microscale and macroscale biogeography of marine microorganisms.
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Affiliation(s)
- Jacob A Cram
- Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, Maryland, USA
| | - Ashley Hollins
- Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, Maryland, USA
| | - Alexandra J McCarty
- Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, Maryland, USA
- Marine Advisory Program, Virginia Institute of Marine Science, Gloucester, Virginia, USA
| | | | - Minming Cui
- Earth and Planetary Sciences, Johns Hopkins University, Baltimore, Maryland, USA
| | - Maya L Gomes
- Earth and Planetary Sciences, Johns Hopkins University, Baltimore, Maryland, USA
| | - Clara A Fuchsman
- Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, Maryland, USA
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8
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Ranheim Sveen T, Hannula SE, Bahram M. Microbial regulation of feedbacks to ecosystem change. Trends Microbiol 2024; 32:68-78. [PMID: 37500365 DOI: 10.1016/j.tim.2023.06.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 06/12/2023] [Accepted: 06/14/2023] [Indexed: 07/29/2023]
Abstract
Microbes are key biodiversity components of all ecosystems and control vital ecosystem functions. Although we have just begun to unravel the scales and factors that regulate microbial communities, their role in mediating ecosystem stability in response to disturbances remains underexplored. Here, we review evidence of how, when, and where microbes regulate or drive disturbance feedbacks. Negative feedbacks dampen the impacts of disturbance, which maintain ecosystem stability, whereas positive feedbacks instead erode stability by amplifying the disturbance. Here we describe the processes underlying the responses to disturbance using a hierarchy of functional traits, and we exemplify how these may drive biogeochemical feedbacks. We suggest that the feedback potential of functional traits at different hierarchical levels is contingent on the complexity and heterogeneity of the environment.
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Affiliation(s)
- T Ranheim Sveen
- Department of Ecology, Swedish University of Agricultural Sciences, Ulls Väg 16, 756 51 Uppsala, Sweden.
| | - S E Hannula
- Institute of Environmental Sciences, Leiden University, Leiden 2333, The Netherlands
| | - M Bahram
- Department of Ecology, Swedish University of Agricultural Sciences, Ulls Väg 16, 756 51 Uppsala, Sweden; Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia
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9
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Li P, Liang W, Zhou Y, Yi Y, He C, Shi Q, He D. Hypoxia diversifies molecular composition of dissolved organic matter and enhances preservation of terrestrial organic carbon in the Yangtze River Estuary. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167661. [PMID: 37813254 DOI: 10.1016/j.scitotenv.2023.167661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 10/05/2023] [Accepted: 10/06/2023] [Indexed: 10/11/2023]
Abstract
Dissolved organic matter (DOM) is an essential component of the global carbon cycle, and estuaries link the rivers and the oceans, thus playing important roles in land-ocean DOM transformation and transport. However, the effects of hypoxia on DOM transport and fate in estuaries and coastal oceans remains poorly understood. To address this gap, we characterized the molecular composition of DOM in bottom water (BW) and sediment porewater (PW) at hypoxic and non-hypoxic sites in the Yangtze River Estuary (YRE) using ultra-high-resolution Fourier transform ion cyclotron resonance mass spectrometry. Our results showed significant differences in DOM molecular composition between hypoxic and non-hypoxic areas for both BW and PW. Specifically, DOM in hypoxic sites was more recalcitrant than that in non-hypoxic areas for both BW and PW, with lower H/C, and higher O/C, double bond equivalent, and modified aromaticity index. The presence of higher polyphenols, and black carbon in hypoxic areas suggested that hypoxic conditions could facilitate the preservation of terrestrial organic matter. Furthermore, we identified a much higher number of hypoxia-unique formulas than ocean-non-hypoxia-unique formulas, indicating that hypoxia could diversify the DOM pool. Within hypoxia-unique formulas for PW, both biologically labile (unsaturated aliphatic compounds and peptides) and recalcitrant formulas (carboxyl-rich alicyclic molecules) were found, suggesting that hypoxia could facilitate the preservation of labile formulas and the production of recalcitrant formulas. In addition, we formulated that the sulfurization is more important in PW than BW in hypoxic areas based on the higher dissolved organic sulfur (DOS) abundance and larger number of hypoxia-only formulas in hypoxic PW, and also the precursor analysis results. Overall, our study provides insights into the effect of hypoxia on the molecular characteristics and preservation of DOM in estuaries and coastal oceans, highlighting the importance of considering hypoxia in understanding the biogeochemical processes of these ecosystems.
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Affiliation(s)
- Penghui Li
- School of Marine Sciences, Sun Yat-sen University, Zhuhai 519082, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China; Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Zhuhai 519082, China
| | - Wenzhao Liang
- Department of Ocean Science, Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Yuping Zhou
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
| | - Yuanbi Yi
- Department of Ocean Science, Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Chen He
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Changping District, Beijing 102249, China
| | - Quan Shi
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Changping District, Beijing 102249, China
| | - Ding He
- Department of Ocean Science, Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Hong Kong, China; State Key Laboratory of Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
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10
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Perkins AK, Rose AL, Grossart HP, Schulz KG, Neubauer D, Tonge MP, Rosentreter JA, Eyre BD, Rojas-Jimenez K, Deschaseaux E, Oakes JM. Fungi increases kelp (Ecklonia radiata) remineralisation and dissolved organic carbon, alkalinity, and dimethylsulfoniopropionate (DMSP) production. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:166957. [PMID: 37704140 DOI: 10.1016/j.scitotenv.2023.166957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 09/06/2023] [Accepted: 09/08/2023] [Indexed: 09/15/2023]
Abstract
Fungi are key players in terrestrial organic matter (OM) degradation, but little is known about their role in marine environments. Here we compared the degradation of kelp (Ecklonia radiata) in mesocosms with and without fungicides over 45 days. The aim was to improve our understanding of the vital role of fungal OM degradation and remineralisation and its relevance to marine biogeochemical cycles (e.g., carbon, nitrogen, sulfur, or volatile sulfur). In the presence of fungi, 68 % of the kelp detritus degraded over 45 days, resulting in the production of 0.6 mol of dissolved organic carbon (DOC), 0.16 mol of dissolved inorganic carbon (DIC), 0.23 mol of total alkalinity (TA), and 0.076 mol of CO2, which was subsequently emitted to the atmosphere. Conversely, when fungi were inhibited, the bacterial community diversity was reduced, and only 25 % of the kelp detritus degraded over 45 days. The application of fungicides resulted in the generation of an excess amount of 1.5 mol of DOC, but we observed only 0.02 mol of DIC, and 0.04 mol of TA per one mole of kelp detritus, accompanied by a CO2 emission of 0.081 mol. In contrast, without fungi, remineralisation of kelp detritus to DIC, TA, dimethyl sulfide (DMS), dimethylsulfoniopropionate (DMSP) and methanethiol (MeSH) was significantly reduced. Fungal kelp remineralisation led to a remarkable 100,000 % increase in DMSP production. The observed substantial changes in sediment chemistry when fungi are inhibited highlight the important biogeochemical role of fungal remineralisation, which likely plays a crucial role in defining coastal biogeochemical cycling, blue carbon sequestration, and thus climate regulation.
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Affiliation(s)
- Anita K Perkins
- Centre for Coastal Biogeochemistry, Faculty of Science and Engineering, Southern Cross University, Lismore, 2480, NSW, Australia; Southern Cross Geoscience, Faculty of Science and Engineering, Southern Cross University, Lismore, 2480, NSW, Australia.
| | - Andrew L Rose
- Centre for Coastal Biogeochemistry, Faculty of Science and Engineering, Southern Cross University, Lismore, 2480, NSW, Australia; Southern Cross Geoscience, Faculty of Science and Engineering, Southern Cross University, Lismore, 2480, NSW, Australia
| | - Hans-Peter Grossart
- Leibniz Institute for Freshwater Ecology and Inland Fisheries (IGB), Experimental Limnology, 16775 Neuglobsow, Germany; University of Potsdam, Institute of Biochemistry and Biology, Maulbeerallee 2, 14469 Potsdam, Germany
| | - Kai G Schulz
- Centre for Coastal Biogeochemistry, Faculty of Science and Engineering, Southern Cross University, Lismore, 2480, NSW, Australia
| | - Darshan Neubauer
- Leibniz Institute for Freshwater Ecology and Inland Fisheries (IGB), Experimental Limnology, 16775 Neuglobsow, Germany; University of Potsdam, Institute of Biochemistry and Biology, Maulbeerallee 2, 14469 Potsdam, Germany
| | - Matthew P Tonge
- Southern Cross Geoscience, Faculty of Science and Engineering, Southern Cross University, Lismore, 2480, NSW, Australia
| | - Judith A Rosentreter
- Centre for Coastal Biogeochemistry, Faculty of Science and Engineering, Southern Cross University, Lismore, 2480, NSW, Australia
| | - Bradley D Eyre
- Centre for Coastal Biogeochemistry, Faculty of Science and Engineering, Southern Cross University, Lismore, 2480, NSW, Australia
| | | | - Elisabeth Deschaseaux
- Centre for Coastal Biogeochemistry, Faculty of Science and Engineering, Southern Cross University, Lismore, 2480, NSW, Australia
| | - Joanne M Oakes
- Centre for Coastal Biogeochemistry, Faculty of Science and Engineering, Southern Cross University, Lismore, 2480, NSW, Australia
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11
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Chen L, Fan T, Yang M, Si D, Wu H, Wu S, Xu J, Zhou D. Sulfurization alters phenol-formaldehyde resin microplastics redox property and their efficiency in mediating arsenite oxidation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 897:166048. [PMID: 37572922 DOI: 10.1016/j.scitotenv.2023.166048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 07/19/2023] [Accepted: 08/02/2023] [Indexed: 08/14/2023]
Abstract
Microplastics weathering by various types of oxidants in the oxic environment and their interaction with environmental contaminants have drawn numerous scientific attention. However, the environmental fate of microplastics under a reducing environment has been largely unresolved. Herein, the change of physicochemical and redox properties of microplastics during the weathering under a sulfate-reducing environment and the interaction with arsenite were addressed. The sulfurization of phenol-formaldehyde resin microplastics under a sulfate-reducing environment generated smooth and porous particles with the induction of organic S species. Multiple spectroscopic results demonstrated thioether and thiophene groups formed by the substitute removal of O-containing functional groups. Moreover, the sulfurization process induced the reduction of carbonyl groups and oxidation of phenolic hydroxyl groups and resulted in the formation of semiquinone radicals. The O-containing functional groups contributed to microplastics redox property and As(III) oxidation while S-containing functional groups showed no obvious effect. The sulfurized microplastics had lower efficiency in mediating arsenite oxidation than the unsulfurized counterparts due to the decreased electron donating capacity. Producing hydrogen peroxides by electron-donating phenol groups and semiquinone radicals and the direct semiquinone radicals oxidation could mediate arsenite oxidation. The findings of this study help us understand the fate of microplastics in redox fluctuation interfaces.
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Affiliation(s)
- Lin Chen
- Ministry of Ecology and Environment of the People's Republic of China, Nanjing Institute of Environmental Sciences, Nanjing 210042, China; State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Tingting Fan
- Ministry of Ecology and Environment of the People's Republic of China, Nanjing Institute of Environmental Sciences, Nanjing 210042, China
| | - Min Yang
- Ministry of Ecology and Environment of the People's Republic of China, Nanjing Institute of Environmental Sciences, Nanjing 210042, China.
| | - Dunfeng Si
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Haotian Wu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Song Wu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Jian Xu
- Ministry of Ecology and Environment of the People's Republic of China, Nanjing Institute of Environmental Sciences, Nanjing 210042, China
| | - Dongmei Zhou
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
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12
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Mugge RL, Moseley RD, Hamdan LJ. Substrate Specificity of Biofilms Proximate to Historic Shipwrecks. Microorganisms 2023; 11:2416. [PMID: 37894074 PMCID: PMC10608953 DOI: 10.3390/microorganisms11102416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 09/13/2023] [Accepted: 09/25/2023] [Indexed: 10/29/2023] Open
Abstract
The number of built structures on the seabed, such as shipwrecks, energy platforms, and pipelines, is increasing in coastal and offshore regions. These structures, typically composed of steel or wood, are substrates for microbial attachment and biofilm formation. The success of biofilm growth depends on substrate characteristics and local environmental conditions, though it is unclear which feature is dominant in shaping biofilm microbiomes. The goal of this study was to understand the substrate- and site-specific impacts of built structures on short-term biofilm composition and functional potential. Seafloor experiments were conducted wherein steel and wood surfaces were deployed for four months at distances extending up to 115 m away from three historic (>50 years old) shipwrecks in the Gulf of Mexico. DNA from biofilms on the steel and wood was extracted, and metagenomes were sequenced on an Illumina NextSeq. A bioinformatics analysis revealed that the taxonomic composition was significantly different between substrates and sites, with substrate being the primary determining factor. Regardless of site, the steel biofilms had a higher abundance of genes related to biofilm formation, and sulfur, iron, and nitrogen cycling, while the wood biofilms showed a higher abundance of manganese cycling and methanol oxidation genes. This study demonstrates how substrate composition shapes biofilm microbiomes and suggests that marine biofilms may contribute to nutrient cycling at depth. Analyzing the marine biofilm microbiome provides insight into the ecological impact of anthropogenic structures on the seabed.
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Affiliation(s)
- Rachel L. Mugge
- U.S. Naval Research Laboratory, Ocean Sciences Division, Stennis Space Center, MS 39529, USA;
| | - Rachel D. Moseley
- School of Ocean Science and Engineering, University of Southern Mississippi, Ocean Springs, MS 39564, USA
| | - Leila J. Hamdan
- School of Ocean Science and Engineering, University of Southern Mississippi, Ocean Springs, MS 39564, USA
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13
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Poulin BA. Selective Photochemical Oxidation of Reduced Dissolved Organic Sulfur to Inorganic Sulfate. ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS 2023; 10:499-505. [PMID: 37333940 PMCID: PMC10275504 DOI: 10.1021/acs.estlett.3c00210] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/26/2023] [Accepted: 04/26/2023] [Indexed: 06/20/2023]
Abstract
The chemical nature and stability of reduced dissolved organic sulfur (DOSRed) have implications on the biogeochemical cycling of trace and major elements across fresh and marine aquatic environments, but the underlying processes governing DOSRed stability remain obscure. Here, dissolved organic matter (DOM) was isolated from a sulfidic wetland, and laboratory experiments quantified dark and photochemical oxidation of DOSRed using atomic-level measurement of sulfur X-ray absorption near-edge structure (XANES) spectroscopy. DOSRed was completely resistant to oxidation by molecular oxygen in the dark and underwent rapid and quantitative oxidation to inorganic sulfate (SO42-) in the presence of sunlight. The rate of DOSRed oxidation to SO42- greatly exceeded that of DOM photomineralization, resulting in a 50% loss of total DOS and 78% loss of DOSRed over 192 h of irradiance. Sulfonates (DOSSO3) and other minor oxidized DOS functionalities were not susceptible to photochemical oxidation. The observed susceptibility of DOSRed to photodesulfurization, which has implications on carbon, sulfur, and mercury cycling, should be comprehensively evaluated across diverse aquatic environments of differing DOM composition.
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Affiliation(s)
- Brett A. Poulin
- Department
of Environmental Toxicology, University
of California Davis, Davis, California 95616, United States
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14
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Tang K, Liu L. Bacteria are driving the ocean's organosulfur cycle. Trends Microbiol 2023:S0966-842X(23)00156-7. [PMID: 37280134 DOI: 10.1016/j.tim.2023.05.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 06/08/2023]
Abstract
Bacteria are key players in the marine sulfur cycle, from the sunlit ocean surface to the dark abyssal depths. Here, we provide a brief overview of the interlinked metabolic processes of organosulfur compounds, an elusive sulfur cycling process that exists in the dark ocean, and the current challenges that limit our understanding of this key nutrient cycle.
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Affiliation(s)
- Kai Tang
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China.
| | - Le Liu
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361005, China
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15
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Zhu Z, Yang L, Xiong Z, Liu D, Hu B, Wang N, Ola O, Zhu Y. SiC@FeZnZiF as a Bifunctional Catalyst with Catalytic Activating PMS and Photoreducing Carbon Dioxide. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13101664. [PMID: 37242081 DOI: 10.3390/nano13101664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 05/04/2023] [Accepted: 05/12/2023] [Indexed: 05/28/2023]
Abstract
Herein, we encapsulated modified silicon carbide nanoparticles utilizing a metal-organic backbone. E-SiC-FeZnZIF composites were successfully prepared via Fe doping. The catalysis activity of this bifunctional composite material was evaluated by the degradation of tetracycline (THC) and carbamazepine (CBZ) and the reduction of carbon dioxide (CO2). Nano SiC has received widespread attention in advanced oxidation applications, especially in the catalytic activation of peroxymonosulfate (PMS). However, the inferior activity of SiC has severely restricted its practical use. In this study of dual functional composite materials, nano SiC was firstly etched under aqueous alkali. Then, zeolite imidazolate frame-8 (ZIF-8) was used for immobilization. The filling of the etched nano SiC with FeZnZiF was confirmed by SEM, XRD, FTIR, BET, and XPS analyses. In addition, E-SiC-FeZnZIF exhibited excellent catalytic activation of peroxymonosulfate (PMS) to oxidize water pollutants, which can degrade tetracycline hydrochloride (THC), achieving a removal rate of 72% within 60 min. Moreover, E-SiC-FeZnZIF exhibited a relatively high CO2 reduction rate with H2O. The yields of CO and CH4 were 0.085 and 0.509 μmol g-1, respectively, after 2 h, which are higher than that of 50 nm of commercial SiC (CO: 0.084 μmol g-1; CH4: 0.209 μmol g-1). This work provides a relatively convenient synthesis path for constructing metal skeleton composites for advanced oxidation and photocatalytic applications. This will have practical significance in protecting water bodies and reducing CO2, which are vital not only for maintaining the natural ecological balance and negative feedback regulation, but also for creating a new application carrier based on nano silicon carbide.
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Affiliation(s)
- Zhiqi Zhu
- Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education, Guangxi Key Laboratory of Disaster Prevention and Engineering Safety, College of Chemistry and Chemical Engineering, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Liaoliao Yang
- Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education, Guangxi Key Laboratory of Disaster Prevention and Engineering Safety, College of Chemistry and Chemical Engineering, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Zhaodong Xiong
- Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education, Guangxi Key Laboratory of Disaster Prevention and Engineering Safety, College of Chemistry and Chemical Engineering, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Daohan Liu
- Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education, Guangxi Key Laboratory of Disaster Prevention and Engineering Safety, College of Chemistry and Chemical Engineering, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Binbin Hu
- Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education, Guangxi Key Laboratory of Disaster Prevention and Engineering Safety, College of Chemistry and Chemical Engineering, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Nannan Wang
- Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education, Guangxi Key Laboratory of Disaster Prevention and Engineering Safety, College of Chemistry and Chemical Engineering, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Oluwafunmilola Ola
- Advanced Materials Group, Faculty of Engineering, The University of Nottingham, Nottingham NG7 2RD, UK
| | - Yanqiu Zhu
- College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4QF, UK
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16
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Tingle KE, Porter SM, Raven MR, Czaja AD, Webb SM, Bloeser B. Organic preservation of vase-shaped microfossils from the late Tonian Chuar Group, Grand Canyon, Arizona, USA. GEOBIOLOGY 2023; 21:290-309. [PMID: 36651474 DOI: 10.1111/gbi.12544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 12/08/2022] [Accepted: 01/05/2023] [Indexed: 06/17/2023]
Abstract
Vase-shaped microfossils (VSMs) are found globally in middle Neoproterozoic (800-730 Ma) marine strata and represent the earliest evidence for testate (shell-forming) amoebozoans. VSM tests are hypothesized to have been originally organic in life but are most commonly preserved as secondary mineralized casts and molds. A few reports, however, suggest possible organic preservation. Here, we test the hypothesis that VSMs from shales of the lower Walcott Member of the Chuar Group, Grand Canyon, Arizona, contain original organic material, as reported by B. Bloeser in her pioneering studies of Chuar VSMs. We identified VSMs from two thin section samples of Walcott Member black shales in transmitted light microscopy and used scanning electron microscopy to image VSMs. Carbonaceous material is found within the internal cavity of all VSM tests from both samples and is interpreted as bitumen mobilized from Walcott shales likely during the Cretaceous. Energy dispersive X-ray spectroscopy (EDS) and wavelength dispersive X-ray spectroscopy (WDS) reveal that VSM test walls contain mostly carbon, iron, and sulfur, while silica is present only in the surrounding matrix. Raman spectroscopy was used to compare the thermal maturity of carbonaceous material within the samples and indicated the presence of pyrite and jarosite within fossil material. X-ray absorption spectroscopy revealed the presence of reduced organic sulfur species within the carbonaceous test walls, the carbonaceous material found within test cavities, and in the sedimentary matrix, suggesting that organic matter sulfurization occurred within the Walcott shales. Our suite of spectroscopic analyses reveals that Walcott VSM test walls are organic and sometimes secondarily pyritized (with the pyrite variably oxidized to jarosite). Both preservation modes can occur at a millimeter spatial scale within sample material, and at times even within a single specimen. We propose that sulfurization within the Walcott Shales promoted organic preservation, and furthermore, the ratio of iron to labile VSM organic material controlled the extent of pyrite replacement. Based on our evidence, we conclude that the VSMs are preserved with original organic test material, and speculate that organic VSMs may often go unrecognized, given their light-colored, translucent appearance in transmitted light.
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Affiliation(s)
- Kelly E Tingle
- Department of Earth Science, University of California, Santa Barbara, California, USA
| | - Susannah M Porter
- Department of Earth Science, University of California, Santa Barbara, California, USA
| | - Morgan R Raven
- Department of Earth Science, University of California, Santa Barbara, California, USA
| | - Andrew D Czaja
- Department of Geology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Samuel M Webb
- Stanford Synchrotron Radiation Lightsource, Stanford University, Menlo Park, California, USA
| | - Bonnie Bloeser
- Department of Geological Sciences, San Diego State University, San Diego, California, USA
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17
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Hu T, Luo M, Qi Y, He D, Chen L, Xu Y, Chen D. Molecular evidence for the production of labile, sulfur-bearing dissolved organic matter in the seep sediments of the South China Sea. WATER RESEARCH 2023; 233:119732. [PMID: 36801578 DOI: 10.1016/j.watres.2023.119732] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 02/05/2023] [Accepted: 02/11/2023] [Indexed: 06/18/2023]
Abstract
Cold seeps with methane-rich fluids leaking out of the seafloor usually support massive biomass of chemosynthetic organisms and associated fauna. A substantial amount of methane is converted to dissolved inorganic carbon by microbial metabolism, and this process also releases dissolved organic matter (DOM) into pore water. Here, pore water samples from "Haima cold seeps" sediments and the non-seep reference sediments in the northern South China Sea were analyzed for optical properties and molecular compositions of pore water DOM. Our results showed that the relative abundance of protein-like DOM, H/Cwa and molecular lability boundary percentage (MLBL%) in the seep sediments were significantly higher than those in the reference sediments, indicating that more labile DOM related to unsaturated aliphatic compounds is produced in the seep sediments. Spearman's correlation of the fluoresce and molecular data suggested that the humic-like components (C1 and C2) mainly constituted the refractory compounds (CRAM, highly unsaturated and aromatics compounds). In contrast, the protein-like component (C3) had high H/C ratios featuring high degree of DOM lability. The amount of S-containing formulas (CHOS and CHONS) was greatly elevated in the seep sediments, likely caused by abiotic and biotic sulfurization of DOM in the sulfidic environment. Although the abiotic sulfurization was proposed to have a stabilizing effect on organic matter, our results implied that the biotic sulfurization in the cold seep sediments would increase DOM lability. Overall, the labile DOM accumulated in the seep sediments is closely linked to methane oxidation, which not only support heterotrophic communities and but also likely have an impact on carbon and sulfur cycling in the sediments and the ocean.
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Affiliation(s)
- Tingcang Hu
- College of Geography and Environment, Liaocheng University, Liaocheng, China
| | - Min Luo
- Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China; Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai, China.
| | - Yulin Qi
- Institute of Surface-Earth System Science, College of Earth System Science, Tianjin University, Tianjin, China
| | - Ding He
- Department of Ocean Science and Hong Kong Branch of the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong, China
| | - Linying Chen
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai, China
| | - Yunping Xu
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai, China
| | - Duofu Chen
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai, China.
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18
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Ceriotti G, Borisov SM, Berg JS, de Anna P. Morphology and Size of Bacterial Colonies Control Anoxic Microenvironment Formation in Porous Media. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:17471-17480. [PMID: 36414252 DOI: 10.1021/acs.est.2c05842] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Bacterial metabolisms using electron acceptors other than oxygen (e.g., methanogenesis and fermentation) largely contribute to element cycling and natural contaminant attenuation/mobilization, even in well-oxygenated porous environments, such as shallow aquifers. This paradox is commonly explained by the occurrence of small-scale anoxic microenvironments generated by the coupling of bacterial respiration and dissolved oxygen (O2) transport by pore water. Such microenvironments allow facultative anaerobic bacteria to proliferate in oxic environments. Microenvironment dynamics are still poorly understood due to the challenge of directly observing biomass and O2 distributions at the microscale within an opaque sediment matrix. To overcome these limitations, we integrated a microfluidic device with transparent O2 planar optical sensors to measure the temporal behavior of dissolved O2 concentrations and biomass distributions with time-lapse videomicroscopy. Our results reveal that bacterial colony morphology, which is highly variable in flowing porous systems, controls the formation of anoxic microenvironments. We rationalize our observations through a colony-scale Damköhler number comparing dissolved O2 diffusion and a bacterial O2 uptake rate. Our Damköhler number enables us to predict the pore space fraction occupied by anoxic microenvironments in our system for a given bacterial organization.
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Affiliation(s)
- Giulia Ceriotti
- Institute of Earth Surface Dynamics, University of Lausanne, Lausanne1015, Switzerland
| | - Sergey M Borisov
- Institute of Analytical Chemistry and Food Chemistry, Graz University of Technology, Graz8010, Austria
| | - Jasmine S Berg
- Institute of Earth Surface Dynamics, University of Lausanne, Lausanne1015, Switzerland
| | - Pietro de Anna
- Institute of Earth Sciences, University of Lausanne, Lausanne1015, Switzerland
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19
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Novel sulfur isotope analyses constrain sulfurized porewater fluxes as a minor component of marine dissolved organic matter. Proc Natl Acad Sci U S A 2022; 119:e2209152119. [PMID: 36201540 PMCID: PMC9565371 DOI: 10.1073/pnas.2209152119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Marine dissolved organic matter (DOM) is a major reservoir that links global carbon, nitrogen, and phosphorus. DOM is also important for marine sulfur biogeochemistry as the largest water column reservoir of organic sulfur. Dissolved organic sulfur (DOS) can originate from phytoplankton-derived biomolecules in the surface ocean or from abiotically "sulfurized" organic matter diffusing from sulfidic sediments. These sources differ in 34S/32S isotope ratios (δ34S values), with phytoplankton-produced DOS tracking marine sulfate (21‰) and sulfurized DOS mirroring sedimentary porewater sulfide (∼0 to -10‰). We measured the δ34S values of solid-phase extracted (SPE) DOM from marine water columns and porewater from sulfidic sediments. Marine DOMSPE δ34S values ranged from 14.9‰ to 19.9‰ and C:S ratios from 153 to 303, with lower δ34S values corresponding to higher C:S ratios. Marine DOMSPE samples showed consistent trends with depth: δ34S values decreased, C:S ratios increased, and δ13C values were constant. Porewater DOMSPE was 34S-depleted (∼-0.6‰) and sulfur-rich (C:S ∼37) compared with water column samples. We interpret these trends as reflecting at most 20% (and on average ∼8%) contribution of abiotic sulfurized sources to marine DOSSPE and conclude that sulfurized porewater is not a main component of oceanic DOS and DOM. We hypothesize that heterogeneity in δ34S values and C:S ratios reflects the combination of sulfurized porewater inputs and preferential microbial scavenging of sulfur relative to carbon without isotope fractionation. Our findings strengthen links between oceanic sulfur and carbon cycling, supporting a realization that organic sulfur, not just sulfate, is important to marine biogeochemistry.
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20
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Ma H, Wang P, Thompson A, Xie Q, Zhu M, Teng HH, Fu P, Liu C, Chen C. Secondary Mineral Formation and Carbon Dynamics during FeS Oxidation in the Presence of Dissolved Organic Matter. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:14120-14132. [PMID: 36151962 DOI: 10.1021/acs.est.1c08727] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Iron (Fe) minerals constitute a major control on organic carbon (OC) storage in soils and sediments. While previous research has mainly targeted Fe (oxyhydr)oxides, the impact of Fe sulfides and their subsequent oxidation on OC dynamics remains unresolved in redox-fluctuating environments. Here, we investigated the impact of dissolved organic matter (DOM) on FeS oxidation and how FeS and its oxidation may alter the retention and nature of DOM. After the anoxic reaction of DOM with FeS, FeS preferentially removed high-molecular-weight and nitrogen-rich compounds and promoted the formation of aqueous sulfurized organic molecules, according to Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS) analysis. When exposed to O2, FeS oxidized to nanocrystalline lepidocrocite and additional aqueous sulfurized organic compounds were generated. The presence of DOM decreased the particle size of the resulting nano-lepidocrocite based on Mössbauer spectroscopy. Following FeS oxidation, most solid-phase OC remained associated with the newly formed lepidocrocite via a monodentate chelating mechanism (based on FTIR analysis), and FeS oxidation caused only a slight increase in the solubilization of solid-phase OC. Collectively, this work highlights the under-appreciated role of Fe sulfides and their oxidation in driving OC transformation and preservation.
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Affiliation(s)
- Hua Ma
- School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Pinya Wang
- School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Aaron Thompson
- Department of Crop and Soil Sciences, University of Georgia, Athens, Georgia 30602, United States
| | - Qiaorong Xie
- School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Mengqiang Zhu
- Department of Ecosystem Science and Management, University of Wyoming, Laramie, Wyoming 82071, United States
| | - Henry H Teng
- School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Pingqing Fu
- School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Congqiang Liu
- School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Chunmei Chen
- School of Earth System Science, Tianjin University, Tianjin 300072, China
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21
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Stenzler BR, Zhang R, Semrau JD, DiSpirito AA, Poulain AJ. Diffusion of H 2 S from anaerobic thiolated ligand biodegradation rapidly generated bioavailable mercury. Environ Microbiol 2022; 24:3212-3228. [PMID: 35621051 DOI: 10.1111/1462-2920.16078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 05/18/2022] [Accepted: 05/18/2022] [Indexed: 11/27/2022]
Abstract
Methylmercury (MeHg) is a potent neurotoxin that biomagnifies through food webs and which production depends on anaerobic microbial uptake of inorganic mercury (Hg) species. One outstanding knowledge gap in understanding Hg methylation is the nature of bioavailable Hg species. It has become increasingly obvious that Hg bioavailability is spatially diverse and temporally dynamic but current models are built on single thiolated ligand systems, mostly omitting ligand exchanges and interactions, or the inclusion of dissolved gaseous phases. In this study, we used a whole-cell anaerobic biosensor to determine the role of a mixture of thiolated ligands on Hg bioavailability. Serendipitously, we discovered how the diffusion of trace amounts of exogenous biogenic H2 S, originating from anaerobic microbial ligand degradation, can alter Hg speciation - away from H2 S production site - to form bioavailable species. Regardless of its origins, H2 S stands as a mobile mediator of microbial Hg metabolism, connecting spatially separated microbial communities. At a larger scale, global planetary changes are expected to accelerate the production and mobilization of H2 S and Hg, possibly leading to increased production of the potent neurotoxin; this work provides mechanistic insights into the importance of co-managing biogeochemical cycle disruptions. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Benjamin R Stenzler
- Biology Department, University of Ottawa, 30 Marie Curie, Ottawa, ON, Canada
| | - Rui Zhang
- Biology Department, University of Ottawa, 30 Marie Curie, Ottawa, ON, Canada
| | - Jeremy D Semrau
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Alan A DiSpirito
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, USA
| | - Alexandre J Poulain
- Biology Department, University of Ottawa, 30 Marie Curie, Ottawa, ON, Canada
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22
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Nabeh N, Brokaw C, Picard A. Quantification of Organic Carbon Sequestered by Biogenic Iron Sulfide Minerals in Long-Term Anoxic Laboratory Incubations. Front Microbiol 2022; 13:662219. [PMID: 35572660 PMCID: PMC9093744 DOI: 10.3389/fmicb.2022.662219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 03/29/2022] [Indexed: 11/13/2022] Open
Abstract
Organic carbon sequestration in sedimentary environments controls oxygen and carbon dioxide concentrations in the atmosphere. While minerals play an important role in the preservation of organic carbon, there is a lack of understanding about the formation and stability of organo-mineral interactions in anoxic environments, especially those involving authigenic iron sulfide minerals. In this study, we quantified organic carbon and nitrogen sequestered in biogenic iron sulfide minerals co-precipitated with sulfate-reducing bacteria (SRB) in freshwater and marine conditions in long-term laboratory experiments. The amounts of C and N associated with biogenic iron sulfide minerals increased with increasing cell biomass concentrations available in the media. C and N levels stabilized over the first 2 months of incubation and remained stable for up to 1 year. Crystalline mackinawite (FeS) formed in all experimental conditions and transformed to greigite only in some experimental conditions. We did not find evidence that this mineral transformation affected C and N levels, neither could we identify the factors that controlled greigite formation. Pyrite did not form in our experimental conditions. While C concentrations in minerals correlated with concentrations of reduced sulfate in both the freshwater and marine media, removal of OC by iron sulfide minerals was more efficient in freshwater than marine conditions. Removal of OC by iron sulfide minerals was also more efficient when cells were present (SRB biomass) in comparison with abiotic incubations with organic mixtures (e.g., tryptone, yeast extract, and casamino acids). Our study highlights the potential for biogenic iron sulfide minerals to quantitatively contribute to organic carbon preservation in anoxic environments.
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Affiliation(s)
- Nader Nabeh
- School of Life Sciences, University of Nevada, Las Vegas, Las Vegas, NV, United States
| | - Cheyenne Brokaw
- School of Life Sciences, University of Nevada, Las Vegas, Las Vegas, NV, United States
| | - Aude Picard
- School of Life Sciences, University of Nevada, Las Vegas, Las Vegas, NV, United States
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23
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Insights into Prokaryotic Community and Its Potential Functions in Nitrogen Metabolism in the Bay of Bengal, a Pronounced Oxygen Minimum Zone. Microbiol Spectr 2022; 10:e0089221. [PMID: 35579458 PMCID: PMC9241787 DOI: 10.1128/spectrum.00892-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ocean oxygen minimum zones (OMZs) around the global ocean are expanding both horizontally and vertically. Multiple studies have identified the significant influence of anoxic conditions (≤1 μM O2) on marine prokaryotic communities and biogeochemical cycling of elements. However, little attention has been paid to the expanding low-oxygen zones where the oxygen level is still above the anoxic level. Here, we studied the abundance and taxonomic and functional profiles of prokaryotic communities in the Bay of Bengal (BoB), where the oxygen concentration is barely above suboxic level (5 μM O2). We found the sinking of Trichodesmium into deep water was far more efficient than that of Prochlorococcus, suggesting Trichodesmium blooms might be an essential carbon and nitrogen source for the maintenance of the BoB OMZ. In addition to the shift in the prokaryotic community composition, the abundance of some functional genes also changed with the change of oxygen concentration. Compared to oxic (>60 μM O2) Tara Ocean and high-hypoxic (>20 to ≤60 μM O2) BoB samples, we found more SAR11-nar sequences (responsible for reducing nitrate to nitrite) in low-hypoxic (>5 to ≤20 μM O2) BoB waters. This suggested SAR11-nar genes would be more widespread due to the expansion of OMZs. It seems that the nitrite-N was not further reduced to nitrogen through denitrification but likely oxidized to nitrate by Nitrospinae in the BoB OMZ and then accumulated in the form of nitrate-N. However, the lack of N2 production in the BoB would change if the BoB OMZ became anoxic. Together, these results suggested that reduction of oxygen concentration and OMZ expansion may increase the use of nitrate by SAR11 and N2 production in the BoB. IMPORTANCE Recognizing the prokaryotic community and its functions in hypoxic (>5 to ≤60 μM O2) environments before further expansion of OMZs is critical. We demonstrate the prokaryotic community and its potential functions in nitrogen metabolism in the Bay of Bengal (BoB), where oxygen concentration is barely above suboxic level. This study highlighted that Trichodesmium might be an essential carbon and nitrogen source in the maintenance of the BoB OMZ. Additionally, we suggest that the lack of N2 production in the BoB would change if the BoB OMZ became anoxic, and the expansion of OMZs in the global ocean may potentially increase the use of nitrate by SAR11.
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24
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Microbial sulfurization stimulates carbon sequestration in marine oxygen minimum zones. Sci Bull (Beijing) 2022; 67:895-898. [PMID: 36546020 DOI: 10.1016/j.scib.2022.01.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 01/06/2022] [Accepted: 01/07/2022] [Indexed: 01/06/2023]
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25
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Microbial Activities and Selection from Surface Ocean to Subseafloor on the Namibian Continental Shelf. Appl Environ Microbiol 2022; 88:e0021622. [PMID: 35404072 PMCID: PMC9088280 DOI: 10.1128/aem.00216-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Oxygen minimum zones (OMZs) are hot spots for redox-sensitive nitrogen transformations fueled by sinking organic matter. In comparison, the regulating role of sulfur-cycling microbes in marine OMZs, their impact on carbon cycling in pelagic and benthic habitats, and activities below the seafloor remain poorly understood. Using 13C DNA stable isotope probing (SIP) and metatranscriptomics, we explored microbial guilds involved in sulfur and carbon cycling from the ocean surface to the subseafloor on the Namibian shelf. There was a clear separation in microbial community structure across the seawater-seafloor boundary, which coincided with a 100-fold-increased concentration of microbial biomass and unique gene expression profiles of the benthic communities. 13C-labeled 16S rRNA genes in SIP experiments revealed carbon-assimilating taxa and their distribution across the sediment-water interface. Most of the transcriptionally active taxa among water column communities that assimilated 13C from diatom exopolysaccharides (mostly Bacteroidetes, Actinobacteria, Alphaproteobacteria, and Planctomycetes) also assimilated 13C-bicarbonate under anoxic conditions in sediment incubations. Moreover, many transcriptionally active taxa from the seafloor community (mostly sulfate-reducing Deltaproteobacteria and sulfide-oxidizing Gammaproteobacteria) that assimilated 13C-bicarbonate under sediment anoxic conditions also assimilated 13C from diatom exopolysaccharides in the surface ocean and OMZ waters. Despite strong selection at the sediment-water interface, many taxa related to either planktonic or benthic communities were found to be present at low abundance and actively assimilating carbon under both sediment and water column conditions. In austral winter, mixing of shelf waters reduces stratification and suspends sediments from the seafloor into the water column, potentially spreading metabolically versatile microbes across niches. IMPORTANCE Microbial activities in oxygen minimum zones (OMZs) transform inorganic fixed nitrogen into greenhouse gases, impacting the Earth’s climate and nutrient equilibrium. Coastal OMZs are predicted to expand with global change and increase carbon sedimentation to the seafloor. However, the role of sulfur-cycling microbes in assimilating carbon in marine OMZs and related seabed habitats remain poorly understood. Using 13C DNA stable isotope probing and metatranscriptomics, we explore microbial guilds involved in sulfur and carbon cycling from ocean surface to subseafloor on the Namibian shelf. Despite strong selection and differential activities across the sediment-water interface, many active taxa were identified in both planktonic and benthic communities, either fixing inorganic carbon or assimilating organic carbon from algal biomass. Our data show that many planktonic and benthic microbes linked to the sulfur cycle can cross redox boundaries when mixing of the shelf waters reduces stratification and suspends seafloor sediment particles into the water column.
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26
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Fuchsman CA, Cherubini L, Hays MD. An analysis of protists in Pacific oxygen deficient zones: implications for Prochlorococcus and N 2 -producing bacteria. Environ Microbiol 2022; 24:1790-1804. [PMID: 34995411 DOI: 10.1111/1462-2920.15893] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 12/27/2021] [Accepted: 12/29/2021] [Indexed: 11/26/2022]
Abstract
Ocean oxygen deficient zones (ODZs) host 30%-50% of marine N2 production. Cyanobacteria photosynthesizing in the ODZ create a secondary chlorophyll maximum and provide organic matter to N2 -producing bacteria. This chlorophyll maximum is thought to occur due to reduced grazing in anoxic waters. We first examine ODZ protists with long amplicon reads. We then use non-primer-based methods to examine the composition and relative abundance of protists in metagenomes from the Eastern Tropical North and South Pacific ODZs and compare these data to the oxic Hawaii Ocean Time-series (HOT) in the North Pacific. We identify and quantify protists in proportion to the total microbial community. From metagenomic data, we see a large drop in abundance of fungi and protists such as choanoflagellates, radiolarians, cercozoa and ciliates in the ODZs but not in the oxic mesopelagic at HOT. Diplonemid euglenozoa were the only protists that increased in the ODZ. Dinoflagellates and foraminifera reads were also present in the ODZ though less abundant compared to oxic waters. Denitrification has been found in foraminifera but not yet in dinoflagellates. DNA techniques cannot separate dinoflagellate cells and cysts. Metagenomic analysis found taxonomic groups missed by amplicon sequencing and identified trends in abundance.
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Affiliation(s)
- Clara A Fuchsman
- University of Maryland Center for Environmental Science Horn Point Laboratory, Cambridge, MD, 21613, USA
| | - Luca Cherubini
- Maryland Sea Grant College, College Park, MD, 20740, USA
| | - Matthew D Hays
- University of Maryland Center for Environmental Science Horn Point Laboratory, Cambridge, MD, 21613, USA
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27
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Chi L, Song X, Ding Y, Yuan Y, Wang W, Cao X, Wu Z, Yu Z. Heterogeneity of the sediment oxygen demand and its contribution to the hypoxia off the Changjiang estuary and its adjacent waters. MARINE POLLUTION BULLETIN 2021; 172:112920. [PMID: 34523426 DOI: 10.1016/j.marpolbul.2021.112920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 08/25/2021] [Accepted: 08/27/2021] [Indexed: 06/13/2023]
Abstract
The severe hypoxia off the Changjiang estuary (CE) has a dual-core structure, and the two hypoxic zones exhibit behavioural, physical and biochemical differences. Currently, few studies have revealed straightforward differences regarding the key biochemical processes between these two hypoxic zones. In this study, the phytoplankton sinking rate (PSR) and sediment oxygen demand (SOD) were measured by field experiments and compared between the two hypoxic regions. PSR and SOD ranged from 0.75-3.34 m day-1 and 5.67-16.19 mmol m-2 day-1, respectively. Interestingly, PSR and SOD were higher in the southern region than in the northern region, implying stronger pelagic-benthic biogeochemical coupling in the southern region. SOD accounted for approximately 44% and 51% of DO net consumption in the northern and southern regions, respectively, from July to August. The southern hypoxic region appeared to exhibit intense DO consumption and fast DO supplementation, while the northern hypoxic region seemed to exhibit slow DO consumption and supplementation.
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Affiliation(s)
- Lianbao Chi
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China
| | - Xiuxian Song
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Yu Ding
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yongquan Yuan
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China
| | - Wentao Wang
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China
| | - Xihua Cao
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China
| | - Zaixing Wu
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China
| | - Zhiming Yu
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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28
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Raven MR, Keil RG, Webb SM. Rapid, concurrent formation of organic sulfur and iron sulfides during experimental sulfurization of sinking marine particles. GLOBAL BIOGEOCHEMICAL CYCLES 2021; 35:e2021GB007062. [PMID: 35756156 PMCID: PMC9231689 DOI: 10.1029/2021gb007062] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Organic matter (OM) sulfurization can enhance the preservation and sequestration of carbon in anoxic sediments, and it has been observed in sinking marine particles from marine O2-deficient zones. The magnitude of this effect on carbon burial remains unclear, however, because the transformations that occur when sinking particles encounter sulfidic conditions remain undescribed. Here, we briefly expose sinking marine particles from the eastern tropical North Pacific O2-deficient zone to environmentally relevant sulfidic conditions (20°C, 0.5 mM [poly]sulfide, two days) and then characterize the resulting solid-phase organic and inorganic products in detail. During these experiments, the abundance of organic sulfur in both hydrolyzable and hydrolysis-resistant solids roughly triples, indicating extensive OM sulfurization. Lipids also sulfurize on this timescale, albeit less extensively. In all three pools, OM sulfurization produces organic monosulfides, thiols, and disulfides. Hydrolyzable sulfurization products appear within ≤ 200-μm regions of relatively homogenous composition that are suggestive of sulfurized extracellular polymeric substances (EPS). Concurrently, reactions with particulate iron oxyhydroxides generate low and fairly uniform concentrations of iron sulfide (FeS) within these same EPS-like materials. Iron oxyhydroxides were not fully consumed during the experiment, which demonstrates that organic materials can be competitive with reactive iron for sulfide. These experiments support the hypothesis that sinking, OM- and EPS-rich particles in a sulfidic water mass can sulfurize within days, potentially contributing to enhanced sedimentary carbon sequestration. Additionally, sulfur-isotope and chemical records of organic S and iron sulfides in sediments have the potential to incorporate signals from water column processes.
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Affiliation(s)
- M R Raven
- Department of Earth Science, University of California, Santa Barbara, Santa Barbara CA 93117, USA
| | - R G Keil
- School of Oceanography, University of Washington, Seattle WA 98195, USA
| | - S M Webb
- Stanford Synchrotron Radiation Lightsource, Stanford University, Menlo Park CA 94025, USA
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29
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Wang L, Lin Y, Ye L, Qian Y, Shi Y, Xu K, Ren H, Geng J. Microbial Roles in Dissolved Organic Matter Transformation in Full-Scale Wastewater Treatment Processes Revealed by Reactomics and Comparative Genomics. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:11294-11307. [PMID: 34338502 DOI: 10.1021/acs.est.1c02584] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Understanding the degradation of dissolved organic matter (DOM) is vital for optimizing DOM control. However, the microbe-mediated DOM transformation during wastewater treatment remains poorly characterized. Here, microbes and DOM along full-scale biotreatment processes were simultaneously characterized using comparative genomics and high-resolution mass spectrometry-based reactomics. Biotreatments significantly increased DOM's aromaticity and unsaturation due to the overproduced lignin and polyphenol analogs. DOM was diversified by over five times in richness, with thousands of nitrogenous and sulfur-containing compounds generated through microbe-mediated oxidoreduction, functional group transfer, and C-N and C-S bond formation. Network analysis demonstrated microbial division of labor in DOM transformation. However, their roles were determined by their functional traits rather than taxa. Specifically, network and module hubs exhibited rapid growth potentials and broad substrate affinities but were deficient in xenobiotics-metabolism-associated genes. They were mainly correlated to liable DOM consumption and its transformation to recalcitrant compounds. In contrast, connectors and peripherals were potential degraders of recalcitrant DOM but slow in growth. They showed specialized associations with fewer DOM molecules and probably fed on metabolites of hub microbes. Thus, developing technologies (e.g., carriers) to selectively enrich peripheral degraders and consequently decouple the liable and recalcitrant DOM transformation processes may advance DOM removal.
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Affiliation(s)
- Liye Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, No. 163, Xianlin Avenue, Nanjing 210023, Jiangsu, P. R. China
| | - Yuan Lin
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, No. 163, Xianlin Avenue, Nanjing 210023, Jiangsu, P. R. China
| | - Lin Ye
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, No. 163, Xianlin Avenue, Nanjing 210023, Jiangsu, P. R. China
| | - Yuli Qian
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, No. 163, Xianlin Avenue, Nanjing 210023, Jiangsu, P. R. China
| | - Yufei Shi
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, No. 163, Xianlin Avenue, Nanjing 210023, Jiangsu, P. R. China
| | - Ke Xu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, No. 163, Xianlin Avenue, Nanjing 210023, Jiangsu, P. R. China
| | - Hongqiang Ren
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, No. 163, Xianlin Avenue, Nanjing 210023, Jiangsu, P. R. China
| | - Jinju Geng
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, No. 163, Xianlin Avenue, Nanjing 210023, Jiangsu, P. R. China
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30
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Savoie ER, Lanclos VC, Henson MW, Cheng C, Getz EW, Barnes SJ, LaRowe DE, Rappé MS, Thrash JC. Ecophysiology of the Cosmopolitan OM252 Bacterioplankton ( Gammaproteobacteria). mSystems 2021; 6:e0027621. [PMID: 34184914 PMCID: PMC8269220 DOI: 10.1128/msystems.00276-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 05/26/2021] [Indexed: 12/27/2022] Open
Abstract
Among the thousands of species that comprise marine bacterioplankton communities, most remain functionally obscure. One key cosmopolitan group in this understudied majority is the OM252 clade of Gammaproteobacteria. Although frequently found in sequence data and even previously cultured, the diversity, metabolic potential, physiology, and distribution of this clade has not been thoroughly investigated. Here, we examined these features of OM252 bacterioplankton using a newly isolated strain and genomes from publicly available databases. We demonstrated that this group constitutes a globally distributed novel genus ("Candidatus Halomarinus"), sister to Litoricola, comprising two subclades and multiple distinct species. OM252 organisms have small genomes (median, 2.21 Mbp) and are predicted obligate aerobes capable of alternating between chemoorganoheterotrophic and chemolithotrophic growth using reduced sulfur compounds as electron donors. Subclade I genomes encode genes for the Calvin-Benson-Bassham cycle for carbon fixation. One representative strain of subclade I, LSUCC0096, had extensive halotolerance and a mesophilic temperature range for growth, with a maximum rate of 0.36 doublings/h at 35°C. Cells were curved rod/spirillum-shaped, ∼1.5 by 0.2 μm. Growth yield on thiosulfate as the sole electron donor under autotrophic conditions was roughly one-third that of heterotrophic growth, even though calculations indicated similar Gibbs energies for both catabolisms. These phenotypic data show that some "Ca. Halomarinus" organisms can switch between serving as carbon sources or sinks and indicate the likely anabolic cost of lithoautotrophic growth. Our results thus provide new hypotheses about the roles of these organisms in global biogeochemical cycling of carbon and sulfur. IMPORTANCE Marine microbial communities are teeming with understudied taxa due to the sheer numbers of species in any given sample of seawater. One group, the OM252 clade of Gammaproteobacteria, has been identified in gene surveys from myriad locations, and one isolated organism has even been genome sequenced (HIMB30). However, further study of these organisms has not occurred. Using another isolated representative (strain LSUCC0096) and publicly available genome sequences from metagenomic and single-cell genomic data sets, we examined the diversity within the OM252 clade and the distribution of these taxa in the world's oceans, reconstructed the predicted metabolism of the group, and quantified growth dynamics in LSUCC0096. Our results generate new knowledge about the previously enigmatic OM252 clade and point toward the importance of facultative chemolithoautotrophy for supporting some clades of ostensibly "heterotrophic" taxa.
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Affiliation(s)
- Emily R. Savoie
- Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, Louisiana, USA
| | - V. Celeste Lanclos
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - Michael W. Henson
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - Chuankai Cheng
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - Eric W. Getz
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - Shelby J. Barnes
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - Douglas E. LaRowe
- Department of Earth Sciences, University of Southern California, Los Angeles, California, USA
| | - Michael S. Rappé
- Hawai’i Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawaiʻi at Mānoa, Kāneʻohe, Hawaii, USA
| | - J. Cameron Thrash
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
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Gomez-Saez GV, Dittmar T, Holtappels M, Pohlabeln AM, Lichtschlag A, Schnetger B, Boetius A, Niggemann J. Sulfurization of dissolved organic matter in the anoxic water column of the Black Sea. SCIENCE ADVANCES 2021; 7:7/25/eabf6199. [PMID: 34134989 PMCID: PMC8208715 DOI: 10.1126/sciadv.abf6199] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 05/04/2021] [Indexed: 05/05/2023]
Abstract
Today's oceans store as much dissolved organic carbon (DOC) in the water column as there is CO2 in the atmosphere, and as such dissolved organic matter (DOM) is an important component of the global carbon cycle. It was shown that in anoxic marine sediments, reduced sulfur species (e.g., H2S) abiotically react with organic matter, contributing to carbon preservation. It is not known whether such processes also contribute to preserving DOM in ocean waters. Here, we show DOM sulfurization within the sulfidic waters of the Black Sea, by combining elemental, isotopic, and molecular analyses. Dissolved organic sulfur (DOS) is formed largely in the water column and not derived from sediments or allochthonous nonmarine sources. Our findings suggest that during large-scale anoxic events, DOM may accumulate through abiotic reactions with reduced sulfur species, having long-lasting effects on global climate by enhancing organic carbon sequestration.
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Affiliation(s)
- Gonzalo V Gomez-Saez
- Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, Oldenburg, Germany.
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Sciences (AWI), Bremerhaven, Germany
| | - Thorsten Dittmar
- Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, Oldenburg, Germany
- Helmholtz Institute for Functional Marine Biodiversity (HIFMB), University of Oldenburg, Oldenburg, Germany
| | - Moritz Holtappels
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Sciences (AWI), Bremerhaven, Germany
- Max Planck Institute for Marine Microbiology (MPI), Bremen, Germany
- MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Anika M Pohlabeln
- Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, Oldenburg, Germany
| | - Anna Lichtschlag
- Max Planck Institute for Marine Microbiology (MPI), Bremen, Germany
- National Oceanography Centre, Southampton, UK
| | - Bernhard Schnetger
- Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, Oldenburg, Germany
| | - Antje Boetius
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Sciences (AWI), Bremerhaven, Germany
- Max Planck Institute for Marine Microbiology (MPI), Bremen, Germany
- MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Jutta Niggemann
- Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, Oldenburg, Germany
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