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Aldeguer-Riquelme B, Antón J, Santos F. Distribution, abundance, and ecogenomics of the Palauibacterales, a new cosmopolitan thiamine-producing order within the Gemmatimonadota phylum. mSystems 2023; 8:e0021523. [PMID: 37345931 PMCID: PMC10469786 DOI: 10.1128/msystems.00215-23] [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: 03/05/2023] [Accepted: 04/19/2023] [Indexed: 06/23/2023] Open
Abstract
The phylum Gemmatimonadota comprises mainly uncultured microorganisms that inhabit different environments such as soils, freshwater lakes, marine sediments, sponges, or corals. Based on 16S rRNA gene studies, the group PAUC43f is one of the most frequently retrieved Gemmatimonadota in marine samples. However, its physiology and ecological roles are completely unknown since, to date, not a single PAUC43f isolate or metagenome-assembled genome (MAG) has been characterized. Here, we carried out a broad study of the distribution, abundance, ecotaxonomy, and metabolism of PAUC43f, for which we propose the name of Palauibacterales. This group was detected in 4,965 16S rRNA gene amplicon datasets, mainly from marine sediments, sponges, corals, soils, and lakes, reaching up to 34.3% relative abundance, which highlights its cosmopolitan character, mainly salt-related. The potential metabolic capabilities inferred from 52 Palauibacterales MAGs recovered from marine sediments, sponges, and saline soils suggested a facultative aerobic and chemoorganotrophic metabolism, although some members may also oxidize hydrogen. Some Palauibacterales species might also play an environmental role as N2O consumers as well as suppliers of serine and thiamine. When compared to the rest of the Gemmatimonadota phylum, the biosynthesis of thiamine was one of the key features of the Palauibacterales. Finally, we show that polysaccharide utilization loci (PUL) are widely distributed within the Gemmatimonadota so that they are not restricted to Bacteroidetes, as previously thought. Our results expand the knowledge about this cryptic phylum and provide new insights into the ecological roles of the Gemmatimonadota in the environment. IMPORTANCE Despite advances in molecular and sequencing techniques, there is still a plethora of unknown microorganisms with a relevant ecological role. In the last years, the mostly uncultured Gemmatimonadota phylum is attracting scientific interest because of its widespread distribution and abundance, but very little is known about its ecological role in the marine ecosystem. Here we analyze the global distribution and potential metabolism of the marine Gemmatimonadota group PAUC43f, for which we propose the name of Palauibacterales order. This group presents a saline-related character and a chemoorganoheterotrophic and facultatively aerobic metabolism, although some species might oxidize H2. Given that Palauibacterales is potentially able to synthesize thiamine, whose auxotrophy is the second most common in the marine environment, we propose Palauibacterales as a key thiamine supplier to the marine communities. This finding suggests that Gemmatimonadota could have a more relevant role in the marine environment than previously thought.
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Affiliation(s)
- Borja Aldeguer-Riquelme
- Department of Physiology, Genetics, and Microbiology, University of Alicante, Alicante, Spain
| | - Josefa Antón
- Department of Physiology, Genetics, and Microbiology, University of Alicante, Alicante, Spain
- Multidisciplinary Institute of Environmental Studies Ramón Margalef, University of Alicante, Alicante, Spain
| | - Fernando Santos
- Department of Physiology, Genetics, and Microbiology, University of Alicante, Alicante, Spain
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Impact of high Fe-concentrations on microbial community structure and dissolved organics in hydrothermal plumes: an experimental study. Sci Rep 2022; 12:20723. [PMID: 36456707 PMCID: PMC9715565 DOI: 10.1038/s41598-022-25320-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 11/28/2022] [Indexed: 12/05/2022] Open
Abstract
Iron (Fe) is an essential trace element for life. In the ocean, Fe can be exceptionally scarce and thus biolimiting or extremely enriched causing microbial stress. The ability of hydrothermal plume microbes to counteract unfavorable Fe-concentrations up to 10 mM is investigated through experiments. While Campylobacterota (Sulfurimonas) are prominent in a diverse community at low to intermediate Fe-concentrations, the highest 10 mM Fe-level is phylogenetically less diverse and dominated by the SUP05 clade (Gammaproteobacteria), a species known to be genetically well equipped to strive in high-Fe environments. In all incubations, Fe-binding ligands were produced in excess of the corresponding Fe-concentration level, possibly facilitating biological Fe-uptake in low-Fe incubations and detoxification in high-Fe incubations. The diversity of Fe-containing formulae among dissolved organics (SPE-DOM) decreased with increasing Fe-concentration, which may reflect toxic conditions of the high-Fe treatments. A DOM-derived degradation index (IDEG) points to a degradation magnitude (microbial activity) that decreases with Fe and/or selective Fe-DOM coagulation. Our results show that some hydrothermal microbes (especially Gammaproteobacteria) have the capacity to thrive even at unfavorably high Fe-concentrations. These ligand-producing microbes could hence play a key role in keeping Fe in solution, particularly in environments, where Fe precipitation dominates and toxic conditions prevail.
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Chen H, Li DH, Jiang AJ, Li XG, Wu SJ, Chen JW, Qu MJ, Qi XQ, Dai J, Zhao R, Zhang WJ, Liu SS, Wu LF. Metagenomic analysis reveals wide distribution of phototrophic bacteria in hydrothermal vents on the ultraslow-spreading Southwest Indian Ridge. MARINE LIFE SCIENCE & TECHNOLOGY 2022; 4:255-267. [PMID: 37073225 PMCID: PMC10077154 DOI: 10.1007/s42995-021-00121-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 08/31/2021] [Indexed: 05/03/2023]
Abstract
Deep-sea hydrothermal vents are known as chemosynthetic ecosystems. However, high temperature vents emit light that hypothetically can drive photosynthesis in this habitat. Metagenomic studies have sporadically reported the occurrence of phototrophic populations such as cyanobacteria in hydrothermal vents. To determine how geographically and taxonomically widespread phototrophs are in deep-sea hydrothermal vents, we collected samples from three niches in a hydrothermal vent on the Southwest Indian Ridge and carried out an integrated metagenomic analysis. We determined the typical community structures of microorganisms found in active venting fields and identified populations of known potential chlorophototrophs and retinalophototrophs. Complete chlorophyll biosynthetic pathways were identified in all samples. By contrast, proteorhodopsins were only found in active beehive smoker diffusers. Taxonomic groups possessing potential phototrophy dependent on semiconductors present in hydrothermal vents were also found in these samples. This systematic comparative metagenomic study reveals the widespread distribution of phototrophic bacteria in hydrothermal vent fields. Our results support the hypothesis that the ocean is a seed bank of diverse microorganisms. Geothermal vent light may provide energy and confer a competitive advantage on phototrophs to proliferate in hydrothermal vent ecosystems. Supplementary Information The online version contains supplementary material available at 10.1007/s42995-021-00121-y.
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Affiliation(s)
- Hong Chen
- Laboratory of Deep Sea Microbial Cell Biology, Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000 China
- University of Chinese Academy of Sciences, Beijing, 100864 China
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France/Sanya, China
- Institution of Deep-Sea Life Sciences, IDSSE-BGI, IDSTI-CAS/Hainan Deep-Sea Technology Laboratory, Sanya/Shenzhen, China
| | - Deng Hui Li
- Institution of Deep-Sea Life Sciences, IDSSE-BGI, IDSTI-CAS/Hainan Deep-Sea Technology Laboratory, Sanya/Shenzhen, China
- BGI-Qingdao, BGI-Shenzhen, Qingdao, 266555 China
| | - Ai Jun Jiang
- Institution of Deep-Sea Life Sciences, IDSSE-BGI, IDSTI-CAS/Hainan Deep-Sea Technology Laboratory, Sanya/Shenzhen, China
- BGI-Qingdao, BGI-Shenzhen, Qingdao, 266555 China
| | - Xue Gong Li
- Laboratory of Deep Sea Microbial Cell Biology, Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000 China
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France/Sanya, China
- Institution of Deep-Sea Life Sciences, IDSSE-BGI, IDSTI-CAS/Hainan Deep-Sea Technology Laboratory, Sanya/Shenzhen, China
| | - Shi Jun Wu
- Zhejiang University, Hangzhou, 310027 China
| | - Jian Wei Chen
- Institution of Deep-Sea Life Sciences, IDSSE-BGI, IDSTI-CAS/Hainan Deep-Sea Technology Laboratory, Sanya/Shenzhen, China
- BGI-Qingdao, BGI-Shenzhen, Qingdao, 266555 China
- BGI-Shenzhen, Shenzhen, 518083 China
- Qingdao-Europe Advanced Institute for Life Sciences, BGI-Shenzhen, Qingdao, 266555 China
| | | | - Xiao Qing Qi
- Laboratory of Deep Sea Microbial Cell Biology, Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000 China
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France/Sanya, China
- Institution of Deep-Sea Life Sciences, IDSSE-BGI, IDSTI-CAS/Hainan Deep-Sea Technology Laboratory, Sanya/Shenzhen, China
| | - Jie Dai
- Laboratory of Deep Sea Microbial Cell Biology, Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000 China
- University of Chinese Academy of Sciences, Beijing, 100864 China
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France/Sanya, China
- Institution of Deep-Sea Life Sciences, IDSSE-BGI, IDSTI-CAS/Hainan Deep-Sea Technology Laboratory, Sanya/Shenzhen, China
| | - Rui Zhao
- Laboratory of Deep Sea Microbial Cell Biology, Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000 China
- University of Chinese Academy of Sciences, Beijing, 100864 China
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France/Sanya, China
- Institution of Deep-Sea Life Sciences, IDSSE-BGI, IDSTI-CAS/Hainan Deep-Sea Technology Laboratory, Sanya/Shenzhen, China
| | - Wei-Jia Zhang
- Laboratory of Deep Sea Microbial Cell Biology, Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000 China
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France/Sanya, China
- Institution of Deep-Sea Life Sciences, IDSSE-BGI, IDSTI-CAS/Hainan Deep-Sea Technology Laboratory, Sanya/Shenzhen, China
| | - Shan Shan Liu
- Institution of Deep-Sea Life Sciences, IDSSE-BGI, IDSTI-CAS/Hainan Deep-Sea Technology Laboratory, Sanya/Shenzhen, China
- BGI-Qingdao, BGI-Shenzhen, Qingdao, 266555 China
- BGI-Shenzhen, Shenzhen, 518083 China
- Qingdao-Europe Advanced Institute for Life Sciences, BGI-Shenzhen, Qingdao, 266555 China
| | - Long-Fei Wu
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France/Sanya, China
- Aix Marseille University, Centre national de la recherche scientifique, Laboratoire de Chimie Bactérienne, Institut de Microbiologie de la Méditerranée, L’ Institut Microbiologie, Bioénergies et Biotechnologie, 13402 Marseille, France
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Dell'Anno F, Rastelli E, Tangherlini M, Corinaldesi C, Sansone C, Brunet C, Balzano S, Ianora A, Musco L, Montereali MR, Dell'Anno A. Highly Contaminated Marine Sediments Can Host Rare Bacterial Taxa Potentially Useful for Bioremediation. Front Microbiol 2021; 12:584850. [PMID: 33732217 PMCID: PMC7956957 DOI: 10.3389/fmicb.2021.584850] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Accepted: 02/02/2021] [Indexed: 01/04/2023] Open
Abstract
Coastal areas impacted by high anthropogenic pressures typically display sediment contamination by polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs). Microbial-based bioremediation represents a promising strategy for sediment reclamation, yet it frequently fails due to poor knowledge of the diversity and dynamics of the autochthonous microbial assemblages and to the inhibition of the target microbes in the contaminated matrix. In the present study, we used an integrated approach including a detailed environmental characterization, high-throughput sequencing and culturing to identify autochthonous bacteria with bioremediation potential in the sediments of Bagnoli-Coroglio (Gulf of Naples, Mediterranean Sea), a coastal area highly contaminated by PAHs, aliphatic hydrocarbons and HMs. The analysis of the benthic prokaryotic diversity showed that the distribution of the dominant taxon (Gammaproteobacteria) was mainly influenced by PAHs, As, and Cd concentrations. The other abundant taxa (including Alphaproteobacteria, Deltaproteobacteria, Bacteroidetes, Acidobacteria, Actinobacteria, NB1-j, Desulfobacterota, and Myxococcota) were mainly driven by sediment grain size and by Cu and Cr concentrations, while the rare taxa (i.e., each contributing <1%) by As and aliphatic hydrocarbons concentrations and by sediment redox potential. These results suggest a differential response of bacterial taxa to environmental features and chemical contamination and those different bacterial groups may be inhibited or promoted by different contaminants. This hypothesis was confirmed by culturing and isolating 80 bacterial strains using media highly enriched in PAHs, only nine of which were contextually resistant to high HM concentrations. Such resistant isolates represented novel Gammaproteobacteria strains affiliated to Vibrio, Pseudoalteromonas, and Agarivorans, which were only scarcely represented in their original assemblages. These findings suggest that rare but culturable bacterial strains resistant/tolerant to high levels of mixed contaminants can be promising candidates useful for the reclamation by bioaugmentation strategies of marine sediments that are highly contaminated with PAHs and HMs.
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Affiliation(s)
| | | | | | - Cinzia Corinaldesi
- Department of Materials, Environmental Sciences and Urban Planning, Polytechnic University of Marche, Ancona, Italy
| | | | | | | | | | - Luigi Musco
- Stazione Zoologica Anton Dohrn, Naples, Italy.,Laboratory of Marine Biology and Zoology, DiSTeBA, University of Salento, Lecce, Italy
| | - Maria Rita Montereali
- ENEA - Agenzia per le Nuove Tecnologie, l'Energia e lo Sviluppo Economico Sostenibile, Rome, Italy
| | - Antonio Dell'Anno
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
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5
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Lai D, Hedlund BP, Xie W, Liu J, Phelps TJ, Zhang C, Wang P. Impact of Terrestrial Input on Deep-Sea Benthic Archaeal Community Structure in South China Sea Sediments. Front Microbiol 2020; 11:572017. [PMID: 33224115 PMCID: PMC7674655 DOI: 10.3389/fmicb.2020.572017] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 10/15/2020] [Indexed: 12/12/2022] Open
Abstract
Archaea are widespread in marine sediments and play important roles in the cycling of sedimentary organic carbon. However, factors controlling the distribution of archaea in marine sediments are not well understood. Here we investigated benthic archaeal communities over glacial-interglacial cycles in the northern South China Sea and evaluated their responses to sediment organic matter sources and inter-species interactions. Archaea in sediments deposited during the interglacial period Marine Isotope Stage (MIS) 1 (Holocene) were significantly different from those in sediments deposited in MIS 2 and MIS 3 of the Last Glacial Period when terrestrial input to the South China Sea was enhanced based on analysis of the long-chain n-alkane C31. The absolute archaeal 16S rRNA gene abundance in subsurface sediments was highest in MIS 2, coincident with high sedimentation rates and high concentrations of total organic carbon. Soil Crenarchaeotic Group (SCG; Nitrososphaerales) species, the most abundant ammonia-oxidizing archaea in soils, increased dramatically during MIS 2, likely reflecting transport of terrestrial archaea during glacial periods with high sedimentation rates. Co-occurrence network analyses indicated significant association of SCG archaea with benthic deep-sea microbes such as Bathyarchaeota and Thermoprofundales in MIS 2 and MIS 3, suggesting potential interactions among these archaeal groups. Meanwhile, Thermoprofundales abundance was positively correlated with total organic carbon (TOC), along with n-alkane C31 and sedimentation rate, indicating that Thermoprofundales may be particularly important in processing of organic carbon in deep-sea sediments. Collectively, these results demonstrate that the composition of heterotrophic benthic archaea in the South China Sea may be influenced by terrestrial organic input in tune with glacial-interglacial cycles, suggesting a plausible link between global climate change and microbial population dynamics in deep-sea marine sediments.
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Affiliation(s)
- Dengxun Lai
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China.,School of Life Sciences, University of Nevada, Las Vegas, NV, United States
| | - Brian P Hedlund
- School of Life Sciences, University of Nevada, Las Vegas, NV, United States.,Nevada Institute of Personalized Medicine, University of Nevada, Las Vegas, NV, United States
| | - Wei Xie
- School of Marine Sciences, Sun Yat-sen University, Zhuhai, China.,Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Jingjing Liu
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China
| | - Tommy J Phelps
- Earth and Planetary Sciences, University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Chuanlun Zhang
- Shenzhen Key Laboratory of Marine Archaea Geo-Omics, Southern University of Science and Technology, Shenzhen, China.,Department of Ocean Science and Engineering, Southern University of Science and Technology, Shenzhen, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China.,Shanghai Sheshan National Geophysical Observatory, Shanghai, China
| | - Peng Wang
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China
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Microbial electroactive biofilms dominated by Geoalkalibacter spp. from a highly saline-alkaline environment. NPJ Biofilms Microbiomes 2020; 6:38. [PMID: 33051461 PMCID: PMC7555509 DOI: 10.1038/s41522-020-00147-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Accepted: 09/11/2020] [Indexed: 11/08/2022] Open
Abstract
Understanding of the extreme microorganisms that possess extracellular electron transfer (EET) capabilities is pivotal to advance electromicrobiology discipline and to develop niche-specific microbial electrochemistry-driven biotechnologies. Here, we report on the microbial electroactive biofilms (EABs) possessing the outward EET capabilities from a haloalkaline environment of the Lonar lake. We used the electrochemical cultivation approach to enrich haloalkaliphilic EABs under 9.5 pH and 20 g/L salinity conditions. The electrodes controlled at 0.2 V vs. Ag/AgCl yielded the best-performing biofilms in terms of maximum bioelectrocatalytic current densities of 548 ± 23 and 437 ± 17 µA/cm2 with acetate and lactate substrates, respectively. Electrochemical characterization of biofilms revealed the presence of two putative redox-active moieties with the mean formal potentials of 0.183 and 0.333 V vs. Ag/AgCl, which represent the highest values reported to date for the EABs. 16S-rRNA amplicon sequencing of EABs revealed the dominance of unknown Geoalkalibacter sp. at ~80% abundance. Further investigations on the haloalkaliphilic EABs possessing EET components with high formal potentials might offer interesting research prospects in electromicrobiology.
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Ma C, Coffinet S, Lipp JS, Hinrichs KU, Zhang C. Marine Group II Euryarchaeota Contribute to the Archaeal Lipid Pool in Northwestern Pacific Ocean Surface Waters. Front Microbiol 2020; 11:1034. [PMID: 32582055 PMCID: PMC7291766 DOI: 10.3389/fmicb.2020.01034] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 04/27/2020] [Indexed: 12/17/2022] Open
Abstract
Planktonic archaea include predominantly Marine Group I Thaumarchaeota (MG I) and Marine Group II Euryarchaeota (MG II), which play important roles in the oceanic carbon cycle. MG I produce specific lipids called isoprenoid glycerol dibiphytanyl glycerol tetraethers (GDGTs), which are being used in the sea surface temperature proxy named TEX86. Although MG II may be the most abundant planktonic archaeal group in surface water, their lipid composition remains poorly characterized because of the lack of cultured representatives. Circumstantial evidence from previous studies of marine suspended particulate matter suggests that MG II may produce both GDGTs and archaeol-based lipids. In this study, integration of the 16S rRNA gene quantification and sequencing and lipid analysis demonstrated that MG II contributed significantly to the pool of archaeal tetraether lipids in samples collected from MG II-dominated surface waters of the Northwestern Pacific Ocean (NWPO). The archaeal lipid composition in MG II-dominated NWPO waters differed significantly from that of known MG I cultures, containing relatively more 2G-OH-, 2G- and 1G- GDGTs, especially in their acyclic form. Lipid composition in NWPO waters was also markedly different from MG I-dominated surface water samples collected in the East China Sea. GDGTs from MG II-dominated samples seemed to respond to temperature similarly to GDGTs from the MG I-dominated samples, which calls for further study using pure cultures to determine the exact impact of MG II on GDGT-based proxies.
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Affiliation(s)
- Cenling Ma
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China
| | - Sarah Coffinet
- Organic Geochemistry Group, MARUM Center for Marine Environmental Sciences and Department of Geosciences, University of Bremen, Bremen, Germany
| | - Julius S Lipp
- Organic Geochemistry Group, MARUM Center for Marine Environmental Sciences and Department of Geosciences, University of Bremen, Bremen, Germany
| | - Kai-Uwe Hinrichs
- Organic Geochemistry Group, MARUM Center for Marine Environmental Sciences and Department of Geosciences, University of Bremen, Bremen, Germany
| | - Chuanlun Zhang
- Shenzhen Key Laboratory of Marine Archaea Geo-Omics, Southern University of Science and Technology, Shenzhen, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
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Du H, Sun T, Wang D, Ming M. Bacterial and archaeal compositions and influencing factors in soils under different submergence time in a mercury-sensitive reservoir. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 191:110155. [PMID: 31972452 DOI: 10.1016/j.ecoenv.2019.110155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 12/27/2019] [Accepted: 12/30/2019] [Indexed: 06/10/2023]
Abstract
Soils in the water-level-fluctuating zone (WLFZ) of Three Gorges Reservoir (TGR) inundated by water for different periods of time are confirmed to have disparate characteristics to mercury (Hg), and thus it is of great significance to further investigate microbial compositions and influencing factors. The objective of this study was to compare bacterial and archaeal richness, α-diversities and compositions, as well as affecting variables, especially Hg concentrations, among soils under different submergence time-SI (inundated soil), SS (semi-inundated soil), SN(non-inundated soil) and SSe (sediment)-based on high throughput sequencing. Results showed that sediment had significantly higher bacterial and archaeal richness and α-diversities than the other soil types. Anaerolinea and Aeromonas, as well as Altiarchaeales, Nitrosoarchaeum, and Methanosarta were dominant in SSe, while sharply decreasing in the other soil types, with significant difference among groups. An unclassified genus in SCG critically predominating in SI, SS and SN, drastically reduced in SSe, with extremely significant difference among groups. Bathyarchaeota and Nitrososphaera, both dominating in SSe, decreased dramatically and almost vanished in SI and SN. All the variables except pH posed a significant positive effect on bacterial and archaeal compositions in SSe, while opposite effect in the other three soil types. MeHg and THg concentrations had relatively weaker effects on microbial compositions comparing to variables like NH4+, CEC, OM and SO42+.
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Affiliation(s)
- Hongxia Du
- College of Resources and Environment, Southwest University, Chongqing, 400715, China; Chongqing Key Laboratory of Bioresource for Bioenergy, Southwest University, Chongqing, 400715, China
| | - Tao Sun
- College of Resources and Environment, Southwest University, Chongqing, 400715, China
| | - Dingyong Wang
- College of Resources and Environment, Southwest University, Chongqing, 400715, China
| | - Ma Ming
- College of Resources and Environment, Southwest University, Chongqing, 400715, China; Chongqing Key Laboratory of Bioresource for Bioenergy, Southwest University, Chongqing, 400715, China.
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Zou D, Pan J, Liu Z, Zhang C, Liu H, Li M. The Distribution of Bathyarchaeota in Surface Sediments of the Pearl River Estuary Along Salinity Gradient. Front Microbiol 2020; 11:285. [PMID: 32174899 PMCID: PMC7056671 DOI: 10.3389/fmicb.2020.00285] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Accepted: 02/07/2020] [Indexed: 01/05/2023] Open
Abstract
Bathyarchaeota, a recently proposed archaeal phylum, is globally distributed and highly abundant in anoxic sediments. Metabolic pathways of the Bathyarchaeota members are diverse and, hence, this phylum has been proposed to play an important role in global biogeochemical cycles. Bathyarchaeota members are distributed in the estuarine environments. However, limited information is available about their detailed community structure, abundance, and functions in the Pearl River estuary (PRE). In the current study, we performed a comprehensive investigation of the archaeal community in the PRE surface sediments along a salinity gradient, with a focus on Bathyarchaeota. Bathyarchaeota was the dominant archaeal phylum, with the abundance of the bathyarchaeotal 16S rRNA gene ranging from 1.43 × 108 to 1.22 × 109 copies/g sediment dry weight (d.w.), and Bathy-8 was the dominant subgroup. Thaumarchaeota, Lokiarchaeota, and Euryarchaeota, including Thermoprofundales (MBG-D archaea), were the other major archaeal groups in the PRE. The differences of community distributions in the high- and low-salinity sediments were hence investigated. Statistical analysis revealed that besides salinity, ammonium, and total organic carbon were the most important environmental factors influencing the archaea community structure, including that of Bathyarchaeota, in the PRE. The archaeal network indicated the cooccurrence among Bathyarchaeota, Lokiarchaeota, and Euryarchaeota, while Bathy-6 presented unique correlations compared with other bathyarchaeotal subgroups. These observations indicate that Bathyarchaeota may play a role in ecosystem function through microbe-microbe interactions, revealing a possible different lifestyle for Bathy-6 in eutrophic estuarine sediments.
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Affiliation(s)
- Dayu Zou
- SZU-HKUST Joint Ph.D. Program in Marine Environmental Science, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Jie Pan
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Zongbao Liu
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Chuanlun Zhang
- Shenzhen Key Laboratory of Marine Archaea Geo-Omics, Southern University of Science and Technology, Shenzhen, China
| | - Hongbin Liu
- Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Meng Li
- SZU-HKUST Joint Ph.D. Program in Marine Environmental Science, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
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Böhnke S, Sass K, Gonnella G, Diehl A, Kleint C, Bach W, Zitoun R, Koschinsky A, Indenbirken D, Sander SG, Kurtz S, Perner M. Parameters Governing the Community Structure and Element Turnover in Kermadec Volcanic Ash and Hydrothermal Fluids as Monitored by Inorganic Electron Donor Consumption, Autotrophic CO 2 Fixation and 16S Tags of the Transcriptome in Incubation Experiments. Front Microbiol 2019; 10:2296. [PMID: 31649639 PMCID: PMC6794353 DOI: 10.3389/fmicb.2019.02296] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 09/20/2019] [Indexed: 12/01/2022] Open
Abstract
The microbial community composition and its functionality was assessed for hydrothermal fluids and volcanic ash sediments from Haungaroa and hydrothermal fluids from the Brothers volcano in the Kermadec island arc (New Zealand). The Haungaroa volcanic ash sediments were dominated by epsilonproteobacterial Sulfurovum sp. Ratios of electron donor consumption to CO2 fixation from respective sediment incubations indicated that sulfide oxidation appeared to fuel autotrophic CO2 fixation, coinciding with thermodynamic estimates predicting sulfide oxidation as the major energy source in the environment. Transcript analyses with the sulfide-supplemented sediment slurries demonstrated that Sulfurovum prevailed in the experiments as well. Hence, our sediment incubations appeared to simulate environmental conditions well suggesting that sulfide oxidation catalyzed by Sulfurovum members drive biomass synthesis in the volcanic ash sediments. For the Haungaroa fluids no inorganic electron donor and responsible microorganisms could be identified that clearly stimulated autotrophic CO2 fixation. In the Brothers hydrothermal fluids Sulfurimonas (49%) and Hydrogenovibrio/Thiomicrospira (15%) species prevailed. Respective fluid incubations exhibited highest autotrophic CO2 fixation if supplemented with iron(II) or hydrogen. Likewise catabolic energy calculations predicted primarily iron(II) but also hydrogen oxidation as major energy sources in the natural fluids. According to transcript analyses with material from the incubation experiments Thiomicrospira/Hydrogenovibrio species dominated, outcompeting Sulfurimonas. Given that experimental conditions likely only simulated environmental conditions that cause Thiomicrospira/Hydrogenovibrio but not Sulfurimonas to thrive, it remains unclear which environmental parameters determine Sulfurimonas’ dominance in the Brothers natural hydrothermal fluids.
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Affiliation(s)
- Stefanie Böhnke
- Molecular Biology of Microbial Consortia, Institute of Plant Science and Microbiology, Universität Hamburg, Hamburg, Germany
| | - Katharina Sass
- Molecular Biology of Microbial Consortia, Institute of Plant Science and Microbiology, Universität Hamburg, Hamburg, Germany
| | - Giorgio Gonnella
- Center for Bioinformatics (ZBH), Universität Hamburg, Hamburg, Germany
| | - Alexander Diehl
- Department of Geosciences, MARUM - Centre for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Charlotte Kleint
- Department of Physics and Earth Sciences, Jacobs University Bremen, Bremen, Germany
| | - Wolfgang Bach
- Department of Geosciences, MARUM - Centre for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Rebecca Zitoun
- Department of Chemistry, University of Otago, Dunedin, New Zealand
| | - Andrea Koschinsky
- Department of Physics and Earth Sciences, Jacobs University Bremen, Bremen, Germany
| | - Daniela Indenbirken
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Hamburg, Germany
| | - Sylvia G Sander
- Department of Chemistry, University of Otago, Dunedin, New Zealand
| | - Stefan Kurtz
- Center for Bioinformatics (ZBH), Universität Hamburg, Hamburg, Germany
| | - Mirjam Perner
- Molecular Biology of Microbial Consortia, Institute of Plant Science and Microbiology, Universität Hamburg, Hamburg, Germany
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11
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Kato S, Nakano S, Kouduka M, Hirai M, Suzuki K, Itoh T, Ohkuma M, Suzuki Y. Metabolic Potential of As-yet-uncultured Archaeal Lineages of Candidatus Hydrothermarchaeota Thriving in Deep-sea Metal Sulfide Deposits. Microbes Environ 2019; 34:293-303. [PMID: 31378759 PMCID: PMC6759336 DOI: 10.1264/jsme2.me19021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Candidatus Hydrothermarchaeota, formally called Marine Benthic Group E, has often been detected in iron- and sulfur-rich marine environments, such as hydrothermal vents and cold seeps. However, their ecology and physiology remain unclear. Cultivated representatives of this group are still lacking and only several metagenome-assembled genomes (MAGs) and single-amplified genomes (SAGs) are available from two deep-sea hydrothermal areas, the Juan de Fuca Ridge (JdFR) and Guaymas Basin (GB), in the north-east Pacific. We herein report four MAGs of Ca. Hydrothermarchaeota recovered from hydrothermally-inactive metal sulfide deposits at the Southern Mariana Trough (SMT) in the north-west Pacific. A phylogenetic analysis indicated that the MAGs of the SMT were distinct from those of the JdFR and GB at the genus or potentially family level. Ca. Hydrothermarchaeota MAGs from the SMT commonly possessed putative genes for carboxydotrophic and hydrogenotrophic respiration using oxidized chemical species of sulfur as electron acceptors and also for carbon fixation, as reported previously in MAGs/SAGs from the JdFR and GB. This result strongly supports Ca. Hydrothermarchaeota containing anaerobic chemolithoautotrophs using carbon monoxide and/or hydrogen as electron donors. A comparative genome analysis highlighted differences in the capability of nitrogen fixation between MAGs from the SMT and the other fields, which are consistent with environmental differences in the availability of nitrogen sources for assimilation between the fields. Based on the wide distribution in various areas, abundance, and metabolic potential of Ca. Hydrothermarchaeota, they may play a role in the biogeochemical cycling of carbon, nitrogen, sulfur, and iron in marine environments, particularly in deep-sea hydrothermal fields.
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Affiliation(s)
- Shingo Kato
- Japan Collection of Microorganisms (JCM), RIKEN BioResource Research Center.,Ore Genesis Research Unit, Project Team for Development of New-generation Research Protocol for Submarine Resources, Japan Agency for Marine-Earth Science and Technology (JAMSTEC)
| | | | | | - Miho Hirai
- Research and Development Center for Marine Biosciences, JAMSTEC
| | - Katsuhiko Suzuki
- Ore Genesis Research Unit, Project Team for Development of New-generation Research Protocol for Submarine Resources, Japan Agency for Marine-Earth Science and Technology (JAMSTEC)
| | - Takashi Itoh
- Japan Collection of Microorganisms (JCM), RIKEN BioResource Research Center
| | - Moriya Ohkuma
- Japan Collection of Microorganisms (JCM), RIKEN BioResource Research Center
| | - Yohey Suzuki
- Graduate School of Science, The University of Tokyo
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12
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Wang Y, Chen X, Guo W, Zhou H. Distinct bacterial and archaeal diversities and spatial distributions in surface sediments of the Arctic Ocean. FEMS Microbiol Lett 2018; 365:5184458. [DOI: 10.1093/femsle/fny273] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 11/13/2018] [Indexed: 12/22/2022] Open
Affiliation(s)
- Yuguang Wang
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, 361005 Xiamen, P.R. China
| | - Xinhua Chen
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, 361005 Xiamen, P.R. China
- College of Animal Sciences, Fujian Agriculture and Forestry University, 350002 Fuzhou, P.R. China
| | - Wenbin Guo
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, 361005 Xiamen, P.R. China
| | - Hongbo Zhou
- School of Minerals Processing and Bioengineering, Central South University, 410083 Changsha, P.R. China
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13
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Cerqueira T, Barroso C, Froufe H, Egas C, Bettencourt R. Metagenomic Signatures of Microbial Communities in Deep-Sea Hydrothermal Sediments of Azores Vent Fields. MICROBIAL ECOLOGY 2018; 76:387-403. [PMID: 29354879 DOI: 10.1007/s00248-018-1144-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 01/02/2018] [Indexed: 05/25/2023]
Abstract
The organisms inhabiting the deep-seafloor are known to play a crucial role in global biogeochemical cycles. Chemolithoautotrophic prokaryotes, which produce biomass from single carbon molecules, constitute the primary source of nutrition for the higher organisms, being critical for the sustainability of food webs and overall life in the deep-sea hydrothermal ecosystems. The present study investigates the metabolic profiles of chemolithoautotrophs inhabiting the sediments of Menez Gwen and Rainbow deep-sea vent fields, in the Mid-Atlantic Ridge. Differences in the microbial community structure might be reflecting the distinct depth, geology, and distance from vent of the studied sediments. A metagenomic sequencing approach was conducted to characterize the microbiome of the deep-sea hydrothermal sediments and the relevant metabolic pathways used by microbes. Both Menez Gwen and Rainbow metagenomes contained a significant number of genes involved in carbon fixation, revealing the largely autotrophic communities thriving in both sites. Carbon fixation at Menez Gwen site was predicted to occur mainly via the reductive tricarboxylic acid cycle, likely reflecting the dominance of sulfur-oxidizing Epsilonproteobacteria at this site, while different autotrophic pathways were identified at Rainbow site, in particular the Calvin-Benson-Bassham cycle. Chemolithotrophy appeared to be primarily driven by the oxidation of reduced sulfur compounds, whether through the SOX-dependent pathway at Menez Gwen site or through reverse sulfate reduction at Rainbow site. Other energy-yielding processes, such as methane, nitrite, or ammonia oxidation, were also detected but presumably contributing less to chemolithoautotrophy. This work furthers our knowledge of the microbial ecology of deep-sea hydrothermal sediments and represents an important repository of novel genes with potential biotechnological interest.
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Affiliation(s)
- Teresa Cerqueira
- Department of Oceanography and Fisheries, University of the Azores, Rua Prof. Dr. Frederico Machado, 9901-862, Horta, Portugal.
- MARE - Marine and Environmental Sciences Centre, 9901-862, Horta, Portugal.
- OKEANOS Research Unit, Faculty of Science and Technology, University of the Azores, 9901-862, Horta, Portugal.
| | - Cristina Barroso
- Next Generation Sequencing Unit - UC-Biotech, Center for Neuroscience and Cell Biology, Parque Tecnológico de Cantanhede, Núcleo 04, Lote 8, 3060-197, Cantanhede, Portugal
- Biocant, Parque Tecnológico de Cantanhede, Núcleo 04, Lote 8, 3060-197, Cantanhede, Portugal
| | - Hugo Froufe
- Biocant, Parque Tecnológico de Cantanhede, Núcleo 04, Lote 8, 3060-197, Cantanhede, Portugal
| | - Conceição Egas
- Next Generation Sequencing Unit - UC-Biotech, Center for Neuroscience and Cell Biology, Parque Tecnológico de Cantanhede, Núcleo 04, Lote 8, 3060-197, Cantanhede, Portugal
- Biocant, Parque Tecnológico de Cantanhede, Núcleo 04, Lote 8, 3060-197, Cantanhede, Portugal
| | - Raul Bettencourt
- MARE - Marine and Environmental Sciences Centre, 9901-862, Horta, Portugal
- OKEANOS Research Unit, Faculty of Science and Technology, University of the Azores, 9901-862, Horta, Portugal
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14
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Hydrothermal chimneys host habitat-specific microbial communities: analogues for studying the possible impact of mining seafloor massive sulfide deposits. Sci Rep 2018; 8:10386. [PMID: 29991752 PMCID: PMC6039533 DOI: 10.1038/s41598-018-28613-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 06/22/2018] [Indexed: 01/17/2023] Open
Abstract
To assess the risk that mining of seafloor massive sulfides (SMS) from extinct hydrothermal vent environments has for changing the ecosystem irreversibly, we sampled SMS analogous habitats from the Kairei and the Pelagia vent fields along the Indian Ridge. In total 19.8 million 16S rRNA tags from 14 different sites were analyzed and the microbial communities were compared with each other and with publicly available data sets from other marine environments. The chimneys appear to provide habitats for microorganisms that are not found or only detectable in very low numbers in other marine habitats. The chimneys also host rare organisms and may function as a vital part of the ocean’s seed bank. Many of the reads from active and inactive chimney samples were clustered into OTUs, with low or no resemblance to known species. Since we are unaware of the chemical reactions catalyzed by these unknown organisms, the impact of this diversity loss and bio-geo-coupling is hard to predict. Given that chimney structures can be considered SMS analogues, removal of sulfide deposits from the seafloor in the Kairei and Pelagia fields will most likely alter microbial compositions and affect element cycling in the benthic regions and probably beyond.
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15
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Pillot G, Frouin E, Pasero E, Godfroy A, Combet-Blanc Y, Davidson S, Liebgott PP. Specific enrichment of hyperthermophilic electroactive Archaea from deep-sea hydrothermal vent on electrically conductive support. BIORESOURCE TECHNOLOGY 2018; 259:304-311. [PMID: 29573609 DOI: 10.1016/j.biortech.2018.03.053] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 03/09/2018] [Accepted: 03/10/2018] [Indexed: 06/08/2023]
Abstract
While more and more investigations are done to study hyperthermophilic exoelectrogenic communities from environments, none have been performed yet on deep-sea hydrothermal vent. Samples of black smoker chimney from Rainbow site on the Atlantic mid-oceanic ridge have been harvested for enriching exoelectrogens in microbial electrolysis cells under hyperthermophilic (80 °C) condition. Two enrichments were performed in a BioElectrochemical System specially designed: one from direct inoculation of crushed chimney and the other one from inoculation of a pre-cultivation on iron (III) oxide. In both experiments, a current production was observed from 2.4 A/m2 to 5.8 A/m2 with a set anode potential of -0.110 V vs Ag/AgCl. Taxonomic affiliation of the exoelectrogen communities obtained on the electrode exhibited a specific enrichment of Archaea belonging to Thermococcales and Archeoglobales orders, even when both inocula were dominated by Bacteria.
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Affiliation(s)
- Guillaume Pillot
- Aix Marseille Université, IRD, Université de Toulon, CNRS, MIO UM 110, Marseille, France
| | - Eléonore Frouin
- Aix Marseille Université, IRD, Université de Toulon, CNRS, MIO UM 110, Marseille, France
| | - Emilie Pasero
- Aix Marseille Université, IRD, Université de Toulon, CNRS, MIO UM 110, Marseille, France
| | - Anne Godfroy
- IFREMER, CNRS, Université de Bretagne Occidentale, Laboratoire de Microbiologie des Environnements Extrêmes - UMR6197, Ifremer, Centre de Brest CS10070, Plouzané, France
| | - Yannick Combet-Blanc
- Aix Marseille Université, IRD, Université de Toulon, CNRS, MIO UM 110, Marseille, France
| | - Sylvain Davidson
- Aix Marseille Université, IRD, Université de Toulon, CNRS, MIO UM 110, Marseille, France
| | - Pierre-Pol Liebgott
- Aix Marseille Université, IRD, Université de Toulon, CNRS, MIO UM 110, Marseille, France.
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16
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Pop Ristova P, Pichler T, Friedrich MW, Bühring SI. Bacterial Diversity and Biogeochemistry of Two Marine Shallow-Water Hydrothermal Systems off Dominica (Lesser Antilles). Front Microbiol 2017; 8:2400. [PMID: 29255454 PMCID: PMC5722836 DOI: 10.3389/fmicb.2017.02400] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Accepted: 11/20/2017] [Indexed: 11/18/2022] Open
Abstract
Shallow-water hydrothermal systems represent extreme environments with unique biogeochemistry and high biological productivity, at which autotrophic microorganisms use both light and chemical energy for the production of biomass. Microbial communities of these ecosystems are metabolically diverse and possess the capacity to transform a large range of chemical compounds. Yet, little is known about their diversity or factors shaping their structure or how they compare to coastal sediments not impacted by hydrothermalism. To this end, we have used automated ribosomal intergenic spacer analysis (ARISA) and high-throughput Illumina sequencing combined with porewater geochemical analysis to investigate microbial communities along geochemical gradients in two shallow-water hydrothermal systems off the island of Dominica (Lesser Antilles). At both sites, venting of hydrothermal fluids substantially altered the porewater geochemistry by enriching it with silica, iron and dissolved inorganic carbon, resulting in island-like habitats with distinct biogeochemistry. The magnitude of fluid flow and difference in sediment grain size, which impedes mixing of the fluids with seawater, were correlated with the observed differences in the porewater geochemistry between the two sites. Concomitantly, individual sites harbored microbial communities with a significantly different community structure. These differences could be statistically linked to variations in the porewater geochemistry and the hydrothermal fluids. The two shallow-water hydrothermal systems of Dominica harbored bacterial communities with high taxonomical and metabolic diversity, predominated by heterotrophic microorganisms associated with the Gammaproteobacterial genera Pseudomonas and Pseudoalteromonas, indicating the importance of heterotrophic processes. Overall, this study shows that shallow-water hydrothermal systems contribute substantially to the biogeochemical heterogeneity and bacterial diversity of coastal sediments.
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Affiliation(s)
- Petra Pop Ristova
- Hydrothermal Geomicrobiology Group, MARUM - Centre for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Thomas Pichler
- Geochemistry and Hydrogeology, University of Bremen, Bremen, Germany
| | - Michael W. Friedrich
- Microbial Ecophysiology Group, Faculty of Biology/Chemistry, Centre for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Solveig I. Bühring
- Hydrothermal Geomicrobiology Group, MARUM - Centre for Marine Environmental Sciences, University of Bremen, Bremen, Germany
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