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Li Y, Guo L, Yang R, Yang Z, Zhang H, Li Q, Cao Z, Zhang X, Gao P, Gao W, Yan G, Huang D, Sun W. Thiobacillus spp. and Anaeromyxobacter spp. mediate arsenite oxidation-dependent biological nitrogen fixation in two contrasting types of arsenic-contaminated soils. JOURNAL OF HAZARDOUS MATERIALS 2023; 443:130220. [PMID: 36308931 DOI: 10.1016/j.jhazmat.2022.130220] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 10/14/2022] [Accepted: 10/18/2022] [Indexed: 06/16/2023]
Abstract
As(III) oxidation-dependent biological nitrogen fixing (As-dependent BNF) bacteria use a novel biogeochemical process observed in tailings recently. However, our understanding of microorganisms responsible for As-dependent BNF is limited and whether such a process occurs in As-contaminated soils is still unknown. In this study, two contrasting types of soils (surface soils versus river sediments) heavily contaminated by As were selected to study the occurrence of As-dependent BNF. BNF was observed in sediments and soils amended with As(III), whereas no apparent BNF was found in the cultures without As(III). The increased abundances of the nitrogenase gene (nifH) and As(III) oxidation gene (aioA) suggest that an As-dependent BNF process was catalyzed by microorganisms harboring nifH and aioA. In addition, DNA-SIP demonstrated that Thiobacillus spp. and Anaeromyxobacter spp. were putative As-dependent BNF bacteria in As-contaminated soils and sediments, respectively. Metagenomic analysis further suggested that these taxa contained genes responsible for BNF, As(III) oxidation, and CO2 fixation, demonstrating their capability for serving as As-dependent BNF. These results indicated the occurrence of As-dependent BNF in various As-contaminated habitats. The contrasting geochemical conditions in different types of soil suggested that these conditions may enrich different As-dependent BNF bacteria (Thiobacillus spp. for soils and Anaeromyxobacter spp. for sediments).
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Affiliation(s)
- Yongbin Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Lifang Guo
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Rui Yang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Zhaohui Yang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China
| | - Haihan Zhang
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Qiqian Li
- College of Chemical and Biological Engineering, Hechi University, Yizhou 546300, China
| | - Zhiguo Cao
- School of Environment, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Normal University, Xinxiang 453007, China
| | - Xin Zhang
- School of Environment, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Normal University, Xinxiang 453007, China
| | - Pin Gao
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Wenlong Gao
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Geng Yan
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Duanyi Huang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Weimin Sun
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.
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Frumkin A, Chipman AD, Naaman I. An isolated chemolithoautotrophic ecosystem deduced from environmental isotopes: Ayyalon cave (Israel). Front Ecol Evol 2023. [DOI: 10.3389/fevo.2022.1040385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The stable isotopes composition of chemolithoautotrophic cave ecosystems is known to differ from epigenic caves. Here we show that in addition, dead carbon (devoid of 14C), is utilized and transferred throughout this ecosystem, rendering it unsuitable for radiocarbon dating. The connectivity of the Ayyalon Cave ecosystem with the surface is studied, along with its sources of energy and carbon, as well as the interconnections between its constituents. We use isotopic evidence to show that its ancient resilient ecosystem is based on an underground food web depending on rich biomass production by chemolithoautotrophic nutrient supplies, detached from surface photosynthesis. Carbon isotopic values indicate that: (1) the microbial biota use bicarbonate from the groundwater (23.34 pMC [% of modern carbon]) rather than the atmospheric CO2 above the water (71.36 pMC); (2) the depleted 14C signal is transferred through the entire ecosystem, indicating that the ecosystem is well-adapted and based on the cave biofilm which is in turn based on groundwater-dissolved inorganic carbon. Incubation of Ayyalon biofilm with 14C-labelled bicarbonate indicates uptake of the radio-labeled bicarbonate by sulfur-oxidizing proteobacteria Beggiatoa, suggesting that these sulfur-oxidizing microorganisms use the water-dissolved inorganic carbon for chemolithoautotrophic carbon fixation. Organic matter in the cave is much lighter in its stable nitrogen and carbon isotopes compared with respective surface values, as expected in chemolithoautotrophic systems. This evidence may be applicative to subsurface voids of ancient Earth environments and extraterrestrial systems.
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Reboleira AS, Bodawatta KH, Ravn NMR, Lauritzen SE, Skoglund RØ, Poulsen M, Michelsen A, Jønsson KA. Nutrient-limited subarctic caves harbour more diverse and complex bacterial communities than their surface soil. ENVIRONMENTAL MICROBIOME 2022; 17:41. [PMID: 35941623 PMCID: PMC9361705 DOI: 10.1186/s40793-022-00435-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 07/08/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Subarctic regions are particularly vulnerable to climate change, yet little is known about nutrient availability and biodiversity of their cave ecosystems. Such knowledge is crucial for predicting the vulnerability of these ecosystems to consequences of climate change. Thus, to improve our understanding of life in these habitats, we characterized environmental variables, as well as bacterial and invertebrate communities of six subarctic caves in Northern Norway. RESULTS Only a minuscule diversity of surface-adapted invertebrates were found in these caves. However, the bacterial communities in caves were compositionally different, more diverse and more complex than the nutrient-richer surface soil. Cave soil microbiomes were less variable between caves than between surface communities in the same area, suggesting that the stable cave environments with tougher conditions drive the uniform microbial communities. We also observed only a small proportion of cave bacterial genera originating from the surface, indicating unique cave-adapted microbial communities. Increased diversity within caves may stem from higher niche specialization and levels of interdependencies for nutrient cycling among bacterial taxa in these oligotrophic environments. CONCLUSIONS Taken together this suggest that environmental changes, e.g., faster melting of snow as a result of global warming that could alter nutrient influx, can have a detrimental impact on interactions and dependencies of these complex communities. This comparative exploration of cave and surface microbiomes also lays the foundation to further investigate the long-term environmental variables that shape the biodiversity of these vulnerable ecosystems.
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Affiliation(s)
- Ana Sofia Reboleira
- Departamento de Biologia Animal, and Centre for Ecology, Evolution and Environmental Changes (cE3c) & CHANGE - Global Change and Sustainability Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisbon, Portugal.
- Natural History Museum of Denmark, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen East, Denmark.
| | - Kasun H Bodawatta
- Departamento de Biologia Animal, and Centre for Ecology, Evolution and Environmental Changes (cE3c) & CHANGE - Global Change and Sustainability Institute, Faculdade de Ciências, Universidade de Lisboa, 1749-016, Lisbon, Portugal
- Natural History Museum of Denmark, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen East, Denmark
| | - Nynne M R Ravn
- Natural History Museum of Denmark, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen East, Denmark
| | - Stein-Erik Lauritzen
- Department of Earth Science, University of Bergen, Allegt. 41, 5007, Bergen, Norway
- Department of Biosciences, Centre for Ecological and Evolutionary Synthesis (CEES), University of Oslo, 0316, Oslo, Norway
| | | | - Michael Poulsen
- Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen East, Denmark
| | - Anders Michelsen
- Section for Terrestrial Ecology, Department of Biology, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen East, Denmark
| | - Knud Andreas Jønsson
- Natural History Museum of Denmark, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen East, Denmark
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Phylotypic Diversity of Bacteria Associated with Speleothems of a Silicate Cave in a Guiana Shield Tepui. Microorganisms 2022; 10:microorganisms10071395. [PMID: 35889113 PMCID: PMC9316562 DOI: 10.3390/microorganisms10071395] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 06/21/2022] [Accepted: 07/07/2022] [Indexed: 12/22/2022] Open
Abstract
The diversity of microorganisms associated with speleological sources has mainly been studied in limestone caves, while studies in silicate caves are still under development. Here, we profiled the microbial diversity of opal speleothems from a silicate cave in Guiana Highlands. Bulk DNAs were extracted from three speleothems of two types, i.e., one soft whitish mushroom-like speleothem and two hard blackish coral-like speleothems. The extracted DNAs were amplified for sequencing the V3–V4 region of the bacterial 16S rRNA gene by MiSeq. A total of 210,309 valid reads were obtained and clustered into 3184 phylotypes or operational taxonomic units (OTUs). The OTUs from the soft whitish speleothem were mostly affiliated with Acidobacteriota, Pseudomonadota (formerly, Proteobacteria), and Chloroflexota, with the OTUs ascribed to Nitrospirota being found specifically in this speleothem. The OTUs from the hard blackish speleothems were similar to each other and were mostly affiliated with Pseudomonadota, Acidobacteriota, and Actinomycetota (formerly, Actinobacteria). These OTU compositions were generally consistent with those reported for limestone and silicate caves. The OTUs were further used to infer metabolic features by using the PICRUSt bioinformatic tool, and membrane transport and amino acid metabolism were noticeably featured. These and other featured metabolisms may influence the pH microenvironment and, consequently, the formation, weathering, and re-deposition of silicate speleothems.
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Variations of Bacterial and Diazotrophic Community Assemblies throughout the Soil Profile in Distinct Paddy Soil Types and Their Contributions to Soil Functionality. mSystems 2022; 7:e0104721. [PMID: 35229646 PMCID: PMC8941939 DOI: 10.1128/msystems.01047-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Soil microbiota plays fundamental roles in maintaining ecosystem functions and services, including biogeochemical processes and plant productivity. Despite the ubiquity of soil microorganisms from the topsoil to deeper layers, their vertical distribution and contribution to element cycling in subsoils remain poorly understood. Here, nine soil profiles (0 to 135 cm) were collected at the local scale (within 300 km) from two canonical paddy soil types (Fe-accumuli and Hapli stagnic anthrosols), representing redoximorphic and oxidative soil types, respectively. Variations with depth in edaphic characteristics and soil bacterial and diazotrophic community assemblies and their associations with element cycling were explored. The results revealed that nitrogen and iron status were the most distinguishing edaphic characteristics of the two soil types throughout the soil profile. The acidic Fe-accumuli stagnic anthrosols were characterized by lower concentrations of free iron oxides and total iron in topsoil and ammonia in deeper layers compared with the Hapli stagnic anthrosols. The bacterial and diazotrophic community assemblies were mainly shaped by soil depth, followed by soil type. Random forest analysis revealed that nitrogen and iron cycling were strongly correlated in Fe-accumuli stagnic anthrosol, whereas in Hapli soil, available sulfur was the most important variable predicting both nitrogen and iron cycling. The distinctive biogeochemical processes could be explained by the differences in enrichment of microbial taxa between the two soil types. The main discriminant clades were the iron-oxidizing denitrifier Rhodanobacter, Actinobacteria, and diazotrophic taxa (iron-reducing Geobacter, Nitrospirillum, and Burkholderia) in Fe-accumuli stagnic anthrosol and the sulfur-reducing diazotroph Desulfobacca in Hapli stagnic anthrosol. IMPORTANCE Rice paddy ecosystems support nearly half of the global population and harbor remarkably diverse microbiomes and functions in a variety of soil types. Diazotrophs provide significant bioavailable nitrogen in paddy soil, priming nitrogen transformation and other biogeochemical processes. This study provides a novel perspective on the vertical distribution of bacterial and diazotrophic communities in two hydragric anthrosols. Microbiome analysis revealed divergent biogeochemical processes in the two paddy soil types, with a dominance of nitrogen-iron cycling processes in Fe-accumuli stagnic anthrosol and sulfur-nitrogen-iron coupling in Hapli stagnic anthrosol. This study advances our understanding of the multiple significant roles played by soil microorganisms, especially diazotrophs, in biogeochemical element cycles, which have important ecological and biogeochemical ramifications.
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Zada S, Xie J, Yang M, Yang X, Sajjad W, Rafiq M, Hasan F, Hu Z, Wang H. Composition and functional profiles of microbial communities in two geochemically and mineralogically different caves. Appl Microbiol Biotechnol 2021; 105:8921-8936. [PMID: 34738169 DOI: 10.1007/s00253-021-11658-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 10/17/2021] [Accepted: 10/22/2021] [Indexed: 12/18/2022]
Abstract
Microbial communities in cave ecosystems have specific survival strategies, which is far from being well explicated. Here, we reported the genetic and functional diversity of bacteria and archaea in typical limestone (Kashmir Cave) and silicate-containing (Tiser Cave) caves. X-ray diffraction (XRD) and Fourier transform infrared spectroscopic (FTIR) analyses revealed the different geochemical and mineral compositions of the two caves. Amplicon barcode sequencing revealed the dominancy of Actinobacteria and Proteobacteria in Kashmir and Tiser Caves. Bacteroidetes and Firmicutes were the dominant phyla in Tiser Cave, and the abundance is relatively small in Kashmir Cave. Archaea was also abundant prokaryotes in Kashmir Cave, but it only accounted for 0.723% of the total prokaryote sequences in Tiser Cave. Functional analysis based on metagenomic sequencing data revealed that a large number of functional potential genes involved in nutrient metabolism and biosynthesis of bioactive compounds in Tiser and Kashmir Cave samples could significantly influence the biogeochemical cycle and secondary metabolite production in cave habitats. In addition, the two caves were also found to be rich in biosynthetic genes, encoding bioactive compounds, such as monobactam and prodigiosin, indicating that these caves could be potential habitats for the isolation of antibiotics. This study provides a comprehensive insight into the diversity of bacteria and archaea in cave ecosystems and helps to better understand the special survival strategies of microorganisms in cave ecosystems.Key points• Geochemically distinct caves possess unique microbial community structure.• Cavernicoles could be important candidates for antibiotic production.• Cavernicoles are important for biogeochemical cycling.
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Affiliation(s)
- Sahib Zada
- Department of Biology, College of Science, Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou, China
| | - Jianmin Xie
- Department of Biology, College of Science, Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou, China
| | - Min Yang
- Department of Biology, College of Science, Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou, China
| | - Xiaoyu Yang
- Department of Biology, College of Science, Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou, China
| | - Wasim Sajjad
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Muhammad Rafiq
- Department of Microbiology, Faculty of Life Sciences and Informatics, Engineering and Management Sciences, Balochistan University of Information Technology, Quetta, Pakistan
| | - Fariha Hasan
- Department of Microbiology, Quaid-I-Azam University, Islamabad, Pakistan
| | - Zhong Hu
- Department of Biology, College of Science, Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou, China
| | - Hui Wang
- Department of Biology, College of Science, Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou, China.
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Chakraborty S, Andersen KH, Visser AW, Inomura K, Follows MJ, Riemann L. Quantifying nitrogen fixation by heterotrophic bacteria in sinking marine particles. Nat Commun 2021; 12:4085. [PMID: 34215729 PMCID: PMC8253789 DOI: 10.1038/s41467-021-23875-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 05/21/2021] [Indexed: 02/06/2023] Open
Abstract
Nitrogen ([Formula: see text]) fixation by heterotrophic bacteria associated with sinking particles contributes to marine N cycling, but a mechanistic understanding of its regulation and significance are not available. Here we develop a mathematical model for unicellular heterotrophic bacteria growing on sinking marine particles. These bacteria can fix [Formula: see text] under suitable environmental conditions. We find that the interactive effects of polysaccharide and polypeptide concentrations, sinking speed of particles, and surrounding [Formula: see text] and [Formula: see text] concentrations determine the [Formula: see text] fixation rate inside particles. [Formula: see text] fixation inside sinking particles is mainly fueled by [Formula: see text] respiration rather than [Formula: see text] respiration. Our model suggests that anaerobic processes, including heterotrophic [Formula: see text] fixation, can take place in anoxic microenvironments inside sinking particles even in fully oxygenated marine waters. The modelled [Formula: see text] fixation rates are similar to bulk rates measured in the aphotic ocean, and our study consequently suggests that particle-associated heterotrophic [Formula: see text] fixation contributes significantly to oceanic [Formula: see text] fixation.
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Affiliation(s)
- Subhendu Chakraborty
- grid.5254.60000 0001 0674 042XDepartment of Biology, Marine Biological Section, University of Copenhagen, Helsingør, Denmark ,grid.5170.30000 0001 2181 8870Centre for Ocean Life, DTU Aqua, Technical University of Denmark, Kgs.Lyngby, Denmark ,grid.461729.f0000 0001 0215 3324Present Address: Systems Ecology Group, Leibniz Centre for Tropical Marine Research (ZMT), Bremen, Germany
| | - Ken H. Andersen
- grid.5170.30000 0001 2181 8870Centre for Ocean Life, DTU Aqua, Technical University of Denmark, Kgs.Lyngby, Denmark
| | - André W. Visser
- grid.5170.30000 0001 2181 8870Centre for Ocean Life, DTU Aqua, Technical University of Denmark, Kgs.Lyngby, Denmark
| | - Keisuke Inomura
- grid.20431.340000 0004 0416 2242Graduate School of Oceanography, University of Rhode Island, Narragansett, RI USA
| | - Michael J. Follows
- grid.116068.80000 0001 2341 2786Department of Earth, Atmospheric and Planetary Sciences, MIT, Cambridge, MA USA
| | - Lasse Riemann
- grid.5254.60000 0001 0674 042XDepartment of Biology, Marine Biological Section, University of Copenhagen, Helsingør, Denmark
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Jabir T, Vipindas PV, Jesmi Y, Divya PS, Adarsh BM, Nafeesathul Miziriya HS, Mohamed Hatha AA. Influence of environmental factors on benthic nitrogen fixation and role of sulfur reducing diazotrophs in a eutrophic tropical estuary. MARINE POLLUTION BULLETIN 2021; 165:112126. [PMID: 33667934 DOI: 10.1016/j.marpolbul.2021.112126] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 01/27/2021] [Accepted: 01/30/2021] [Indexed: 05/20/2023]
Abstract
Benthic nitrogen fixation in the tropical estuaries plays a major role in marine nitrogen cycle, its contribution to nitrogen budget and players behind process is not well understood. The present study was estimated the benthic nitrogen fixation rate in a tropical estuary (Cochin) and also evaluated the contribution of various diazotrophic bacterial communities. Nitrogen fixation was detected throughout year (0.1-1.11 nmol N g-1 h-1); higher activity was observed in post-monsoon. The nifH gene abundance was varied from 0.8 × 104 to 0.6 × 108 copies g-1dry sediment; highest was detected in post-monsoon. The Cluster I and Cluster III were the dominant diazotrophs. Sulfur reducing bacterial phylotypes (Deltaproteobacteria) contributed up to 2-72% of total nitrogen fixation. These bacteria may provide new nitrogen to these systems, counteracting nitrogen loss via denitrification and anammox. Overall, the study explained the importance of benthic nitrogen fixation and role of diazotrophs in a monsoon influenced tropical estuarine environments.
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Affiliation(s)
- T Jabir
- Department of Marine Biology, Microbiology, Biochemistry, School of Marine Sciences, Cochin University of Science and Technology (CUSAT), Kochi 682016, India; National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Headland Sada, Vasco-da-Gama, Goa 403 804, India.
| | - P V Vipindas
- Department of Marine Biology, Microbiology, Biochemistry, School of Marine Sciences, Cochin University of Science and Technology (CUSAT), Kochi 682016, India; National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Headland Sada, Vasco-da-Gama, Goa 403 804, India
| | - Y Jesmi
- Department of Marine Biology, Microbiology, Biochemistry, School of Marine Sciences, Cochin University of Science and Technology (CUSAT), Kochi 682016, India
| | - P S Divya
- Department of Marine Biology, Microbiology, Biochemistry, School of Marine Sciences, Cochin University of Science and Technology (CUSAT), Kochi 682016, India
| | - B M Adarsh
- Department of Marine Biology, Microbiology, Biochemistry, School of Marine Sciences, Cochin University of Science and Technology (CUSAT), Kochi 682016, India
| | - H S Nafeesathul Miziriya
- Department of Marine Biology, Microbiology, Biochemistry, School of Marine Sciences, Cochin University of Science and Technology (CUSAT), Kochi 682016, India
| | - A A Mohamed Hatha
- Department of Marine Biology, Microbiology, Biochemistry, School of Marine Sciences, Cochin University of Science and Technology (CUSAT), Kochi 682016, India; CUSAT-NCPOR Centre for Polar Sciences, Cochin University of Science and Technology (CUSAT), Kochi 682 016, India.
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Petersen JM, Yuen B. The symbiotic 'all-rounders': Partnerships between marine animals and chemosynthetic nitrogen-fixing bacteria. Appl Environ Microbiol 2021; 87:AEM.02129-20. [PMID: 33355107 PMCID: PMC8090883 DOI: 10.1128/aem.02129-20] [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] [Indexed: 11/20/2022] Open
Abstract
Nitrogen fixation is a widespread metabolic trait in certain types of microorganisms called diazotrophs. Bioavailable nitrogen is limited in various habitats on land and in the sea, and accordingly, a range of plant, animal, and single-celled eukaryotes have evolved symbioses with diverse diazotrophic bacteria, with enormous economic and ecological benefits. Until recently, all known nitrogen-fixing symbionts were heterotrophs such as nodulating rhizobia, or photoautotrophs such as cyanobacteria. In 2016, the first chemoautotrophic nitrogen-fixing symbionts were discovered in a common family of marine clams, the Lucinidae. Chemosynthetic nitrogen-fixing symbionts use the chemical energy stored in reduced sulfur compounds to power carbon and nitrogen fixation, making them metabolic 'all-rounders' with multiple functions in the symbiosis. This distinguishes them from heterotrophic symbionts that require a source of carbon from their host, and their chemosynthetic metabolism distinguishes them from photoautotrophic symbionts that produce oxygen, a potent inhibitor of nitrogenase. In this review, we consider evolutionary aspects of this discovery, by comparing strategies that have evolved for hosting intracellular nitrogen-fixing symbionts in plants and animals. The symbiosis between lucinid clams and chemosynthetic nitrogen-fixing bacteria also has important ecological impacts, as they form a nested symbiosis with endangered marine seagrasses. Notably, nitrogen fixation by lucinid symbionts may help support seagrass health by providing a source of nitrogen in seagrass habitats. These discoveries were enabled by new techniques for understanding the activity of microbial populations in natural environments. However, an animal (or plant) host represents a diverse landscape of microbial niches due to its structural, chemical, immune and behavioural properties. In future, methods that resolve microbial activity at the single cell level will provide radical new insights into the regulation of nitrogen fixation in chemosynthetic symbionts, shedding new light on the evolution of nitrogen-fixing symbioses in contrasting hosts and environments.
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Affiliation(s)
- Jillian M Petersen
- Centre for Microbiology and Environmental Systems Science, University of Vienna
| | - Benedict Yuen
- Centre for Microbiology and Environmental Systems Science, University of Vienna
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Bacteria and Metabolic Potential in Karst Caves Revealed by Intensive Bacterial Cultivation and Genome Assembly. Appl Environ Microbiol 2021; 87:AEM.02440-20. [PMID: 33452024 DOI: 10.1128/aem.02440-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 01/05/2021] [Indexed: 12/26/2022] Open
Abstract
Karst caves are widely distributed subsurface systems, and the microbiomes therein are proposed to be the driving force for cave evolution and biogeochemical cycling. In past years, culture-independent studies on the microbiomes of cave systems have been conducted, yet intensive microbial cultivation is still needed to validate the sequence-derived hypothesis and to disclose the microbial functions in cave ecosystems. In this study, the microbiomes of two karst caves in Guizhou Province in southwest China were examined. A total of 3,562 bacterial strains were cultivated from rock, water, and sediment samples, and 329 species (including 14 newly described species) of 102 genera were found. We created a cave bacterial genome collection of 218 bacterial genomes from a karst cave microbiome through the extraction of 204 database-derived genomes and de novo sequencing of 14 new bacterial genomes. The cultivated genome collection obtained in this study and the metagenome data from previous studies were used to investigate the bacterial metabolism and potential involvement in the carbon, nitrogen, and sulfur biogeochemical cycles in the cave ecosystem. New N2-fixing Azospirillum and alkane-oxidizing Oleomonas species were documented in the karst cave microbiome. Two pcaIJ clusters of the β-ketoadipate pathway that were abundant in both the cultivated microbiomes and the metagenomic data were identified, and their representatives from the cultivated bacterial genomes were functionally demonstrated. This large-scale cultivation of a cave microbiome represents the most intensive collection of cave bacterial resources to date and provides valuable information and diverse microbial resources for future cave biogeochemical research.IMPORTANCE Karst caves are oligotrophic environments that are dark and humid and have a relatively stable annual temperature. The diversity of bacteria and their metabolisms are crucial for understanding the biogeochemical cycling in cave ecosystems. We integrated large-scale bacterial cultivation with metagenomic data mining to explore the compositions and metabolisms of the microbiomes in two karst cave systems. Our results reveal the presence of a highly diversified cave bacterial community, and 14 new bacterial species were described and their genomes sequenced. In this study, we obtained the most intensive collection of cultivated microbial resources from karst caves to date and predicted the various important routes for the biogeochemical cycling of elements in cave ecosystems.
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11
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Dong Y, Gao J, Wu Q, Ai Y, Huang Y, Wei W, Sun S, Weng Q. Co-occurrence pattern and function prediction of bacterial community in Karst cave. BMC Microbiol 2020; 20:137. [PMID: 32471344 PMCID: PMC7257168 DOI: 10.1186/s12866-020-01806-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 04/28/2020] [Indexed: 01/20/2023] Open
Abstract
Background Karst caves are considered as extreme environments with nutrition deficiency, darkness, and oxygen deprivation, and they are also the sources of biodiversity and metabolic pathways. Microorganisms are usually involved in the formation and maintenance of the cave system through various metabolic activities, and are indicators of changes environment influenced by human. Zhijin cave is a typical Karst cave and attracts tourists in China. However, the bacterial diversity and composition of the Karst cave are still unclear. The present study aims to reveal the bacterial diversity and composition in the cave and the potential impact of tourism activities, and better understand the roles and co-occurrence pattern of the bacterial community in the extreme cave habitats. Results The bacterial community consisted of the major Proteobacteria, Actinobacteria, and Firmicutes, with Proteobacteria being the predominant phylum in the rock, soil, and stalactite samples. Compositions and specialized bacterial phyla of the bacterial communities were different among different sample types. The highest diversity index was found in the rock samples with a Shannon index of 4.71. Overall, Zhijin cave has relatively lower diversity than that in natural caves. The prediction of function showed that various enzymes, including ribulose-bisphosphate carboxylase, 4-hydroxybutyryl-CoA dehydratase, nitrogenase NifH, and Nitrite reductase, involved in carbon and nitrogen cycles were detected in Zhijin cave. Additionally, the modularity indices of all co-occurrence network were greater than 0.40 and the species interactions were complex across different sample types. Co-occurring positive interactions in the bacteria groups in different phyla were also observed. Conclusion These results uncovered that the oligotrophic Zhijin cave maintains the bacterial communities with the diverse metabolic pathways, interdependent and cooperative co-existence patterns. Moreover, as a hotspot for tourism, the composition and diversity of bacterial community are influenced by tourism activities. These afford new insights for further exploring the adaptation of bacteria to extreme environments and the conservation of cave ecosystem.
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Affiliation(s)
- Yiyi Dong
- School of Life Sciences, Guizhou Normal University, Guiyang, 550001, Guizhou, China.,CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, 666303, Yunnan, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jie Gao
- CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, 666303, Yunnan, China.,Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Mengla, 666303, Yunnan, China
| | - Qingshan Wu
- School of Life Sciences, Guizhou Normal University, Guiyang, 550001, Guizhou, China
| | - Yilang Ai
- School of Life Sciences, Guizhou Normal University, Guiyang, 550001, Guizhou, China
| | - Yu Huang
- School of Life Sciences, Guizhou Normal University, Guiyang, 550001, Guizhou, China
| | - Wenzhang Wei
- School of Life Sciences, Guizhou Normal University, Guiyang, 550001, Guizhou, China.,Department of Bioengineering and Biotechnology, Huaqiao University, Xiamen, 361021, Fujian, China
| | - Shiyu Sun
- School of Life Sciences, Guizhou Normal University, Guiyang, 550001, Guizhou, China
| | - Qingbei Weng
- School of Life Sciences, Guizhou Normal University, Guiyang, 550001, Guizhou, China.
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12
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Sun X, Kong T, Häggblom MM, Kolton M, Li F, Dong Y, Huang Y, Li B, Sun W. Chemolithoautotropic Diazotrophy Dominates the Nitrogen Fixation Process in Mine Tailings. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:6082-6093. [PMID: 32216300 DOI: 10.1021/acs.est.9b07835] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Nutrient deficiency, especially bio-available nitrogen deficiency, often impedes the bioremediation efforts of mining generated tailings. Biological nitrogen fixation is a critical process necessary for the initial nitrogen buildup in tailings. Current knowledge regarding the diazotrophs that inhabit tailings is still in its infancy. Therefore, in this study, a comprehensive investigation combining geochemical characterization, sequence analyses, molecular techniques, and activity measurements was conducted to characterize the diazotrophic community residing in tailing environments. Significant differences between tailings and their adjacent soils in prokaryotic and diazotrophic communities were detected. Meanwhile, strong and significant correlations between the absolute abundance of the nitrogen fixation (nifH), carbon fixation (cbbL), sulfur oxidation (soxB), and arsenite oxidation (aioA) genes were observed in the tailings but not in the soils. The reconstructed nif-containing metagenome-assembled genomes (MAGs) suggest that the carbon fixation and sulfur oxidation pathways were important for potential diazotrophs inhabiting the tailings. Activity measurements further confirmed that diazotrophs inhabiting tailings preferentially use inorganic electron donors (e.g., elemental sulfur) compared to organic electron donors (e.g., sucrose), while diazotrophs inhabiting soils preferred organic carbon sources. Collectively, these findings suggest that chemolithoautotrophic diazotrophs may play essential roles in acquiring nutrients and facilitating ecological succession in tailings.
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Affiliation(s)
- Xiaoxu Sun
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou 510650, China
| | - Tianle Kong
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou 510650, China
- School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, China
| | - Max M Häggblom
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, New Jersey 08901, United States
| | - Max Kolton
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou 510650, China
| | - Fangbai Li
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou 510650, China
| | - Yiran Dong
- School of Environmental Studies, China University of Geosciences (Wuhan), Wuhan 430074, China
| | - Yuqing Huang
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou 510650, China
| | - Baoqin Li
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou 510650, China
| | - Weimin Sun
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-environmental Science & Technology, Guangzhou 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou 510650, China
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Wiseschart A, Mhuantong W, Tangphatsornruang S, Chantasingh D, Pootanakit K. Shotgun metagenomic sequencing from Manao-Pee cave, Thailand, reveals insight into the microbial community structure and its metabolic potential. BMC Microbiol 2019; 19:144. [PMID: 31248378 PMCID: PMC6598295 DOI: 10.1186/s12866-019-1521-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 06/19/2019] [Indexed: 12/21/2022] Open
Abstract
Background Due to the cave oligotrophic environment, this habitat presents a challenge for microorganisms to colonize and thrive. However, it has been well documented that microorganisms play important roles in cave development. Survival of microbes in this unique habitat likely involves a broad range of adaptive capabilities. Recently, cave microbiomes all over the world are of great scientific interest. However, the majority of investigations focused mostly on small subunit ribosomal RNA (16S rRNA) gene, leaving the ecological role of the microbial community largely unknown. Here, we are particularly interested in exploring the taxonomic composition and metabolic potential of microorganisms in soil from Manao-Pee cave, a subterranean limestone cave in the western part of Thailand, by using high-throughput shotgun metagenomic sequencing. Results From taxonomic composition analysis using ribosomal RNA genes (rRNA), the results confirmed that Actinobacteria (51.2%) and Gammaproteobacteria (24.4%) were the dominant bacterial groups in the cave soil community. Metabolic potential analysis, based on six functional modules of the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, revealed that functional genes involved in microbial metabolisms are highly represented in this community (40.6%). To better understand how microbes thrive under unfavorable cave condition, we focused on microbial energy metabolism. The results showed that microbial genes involved in oxidative phosphorylation were the most dominant (28.8%) in Manao-Pee cave, and were followed by methane metabolism (20.5%), carbon fixation (16.0%), nitrogen metabolism (14.7%), and sulfur metabolism (6.3%). In addition, microbial genes involved in xenobiotic biodegradation (26 pathways) and in production of secondary metabolites (27 pathways) were also identified. Conclusion In addition to providing information on microbial diversity, we also gained insights into microbial adaptations and survival strategies under cave conditions. Based on rRNA genes, the results revealed that bacteria belonging to the Actinobacteria and Gammaproteobacteria were the most abundant in this community. From metabolic potential analysis, energy and nutrient sources that sustain diverse microbial population in this community might be atmospheric gases (methane, carbon dioxide, nitrogen), inorganic sulfur, and xenobiotic compounds. In addition, the presence of biosynthetic pathways of secondary metabolites suggested that they might play important ecological roles in the cave microbiome. Electronic supplementary material The online version of this article (10.1186/s12866-019-1521-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Apirak Wiseschart
- Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Phuttamonthon 4 Rd, Salaya, Nakhon Pathom, 73170, Thailand
| | - Wuttichai Mhuantong
- National Center for Genetic Engineering and Biotechnology (BIOTEC), 133 Thailand Science Park, Paholyothin Rd, Klong 1, Klongluang, Pathumthani, 12120, Thailand
| | - Sithichoke Tangphatsornruang
- National Center for Genetic Engineering and Biotechnology (BIOTEC), 133 Thailand Science Park, Paholyothin Rd, Klong 1, Klongluang, Pathumthani, 12120, Thailand
| | - Duriya Chantasingh
- National Center for Genetic Engineering and Biotechnology (BIOTEC), 133 Thailand Science Park, Paholyothin Rd, Klong 1, Klongluang, Pathumthani, 12120, Thailand
| | - Kusol Pootanakit
- Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Phuttamonthon 4 Rd, Salaya, Nakhon Pathom, 73170, Thailand.
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14
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Gregory SP, Barnett MJ, Field LP, Milodowski AE. Subsurface Microbial Hydrogen Cycling: Natural Occurrence and Implications for Industry. Microorganisms 2019; 7:E53. [PMID: 30769950 PMCID: PMC6407114 DOI: 10.3390/microorganisms7020053] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 02/01/2019] [Accepted: 02/03/2019] [Indexed: 12/21/2022] Open
Abstract
Hydrogen is a key energy source for subsurface microbial processes, particularly in subsurface environments with limited alternative electron donors, and environments that are not well connected to the surface. In addition to consumption of hydrogen, microbial processes such as fermentation and nitrogen fixation produce hydrogen. Hydrogen is also produced by a number of abiotic processes including radiolysis, serpentinization, graphitization, and cataclasis of silicate minerals. Both biotic and abiotically generated hydrogen may become available for consumption by microorganisms, but biotic production and consumption are usually tightly coupled. Understanding the microbiology of hydrogen cycling is relevant to subsurface engineered environments where hydrogen-cycling microorganisms are implicated in gas consumption and production and corrosion in a number of industries including carbon capture and storage, energy gas storage, and radioactive waste disposal. The same hydrogen-cycling microorganisms and processes are important in natural sites with elevated hydrogen and can provide insights into early life on Earth and life on other planets. This review draws together what is known about microbiology in natural environments with elevated hydrogen, and highlights where similar microbial populations could be of relevance to subsurface industry.
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Affiliation(s)
- Simon P Gregory
- British Geological Survey, Environmental Science Centre, Keyworth, Nottingham NG12 5GG, UK.
| | - Megan J Barnett
- British Geological Survey, Environmental Science Centre, Keyworth, Nottingham NG12 5GG, UK.
| | - Lorraine P Field
- British Geological Survey, Environmental Science Centre, Keyworth, Nottingham NG12 5GG, UK.
| | - Antoni E Milodowski
- British Geological Survey, Environmental Science Centre, Keyworth, Nottingham NG12 5GG, UK.
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15
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Microbial diversity and biosignatures of amorphous silica deposits in orthoquartzite caves. Sci Rep 2018; 8:17569. [PMID: 30514906 PMCID: PMC6279750 DOI: 10.1038/s41598-018-35532-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 10/30/2018] [Indexed: 11/08/2022] Open
Abstract
Chemical mobility of crystalline and amorphous SiO2 plays a fundamental role in several geochemical and biological processes, with silicate minerals being the most abundant components of the Earth's crust. Although the oldest evidences of life on Earth are fossilized in microcrystalline silica deposits, little is known about the functional role that bacteria can exert on silica mobility at non-thermal and neutral pH conditions. Here, a microbial influence on silica mobilization event occurring in the Earth's largest orthoquartzite cave is described. Transition from the pristine orthoquartzite to amorphous silica opaline precipitates in the form of stromatolite-like structures is documented through mineralogical, microscopic and geochemical analyses showing an increase of metals and other bioessential elements accompanied by permineralized bacterial cells and ultrastructures. Illumina sequencing of the 16S rRNA gene describes the bacterial diversity characterizing the consecutive amorphization steps to provide clues on the biogeochemical factors playing a role in the silica solubilization and precipitation processes. These results show that both quartz weathering and silica mobility are affected by chemotrophic bacterial communities, providing insights for the understanding of the silica cycle in the subsurface.
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16
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Nishihara A, Haruta S, McGlynn SE, Thiel V, Matsuura K. Nitrogen Fixation in Thermophilic Chemosynthetic Microbial Communities Depending on Hydrogen, Sulfate, and Carbon Dioxide. Microbes Environ 2018; 33:10-18. [PMID: 29367473 PMCID: PMC5877335 DOI: 10.1264/jsme2.me17134] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 10/28/2017] [Indexed: 12/20/2022] Open
Abstract
The activity of nitrogen fixation measured by acetylene reduction was examined in chemosynthetic microbial mats at 72-75°C in slightly-alkaline sulfidic hot springs in Nakabusa, Japan. Nitrogenase activity markedly varied from sampling to sampling. Nitrogenase activity did not correlate with methane production, but was detected in samples showing methane production levels less than the maximum amount, indicating a possible redox dependency of nitrogenase activity. Nitrogenase activity was not affected by 2-bromo-ethane sulfonate, an inhibitor of methanogenesis. However, it was inhibited by the addition of molybdate, an inhibitor of sulfate reduction and sulfur disproportionation, suggesting the involvement of sulfate-reducing or sulfur-disproportionating organisms. Nitrogenase activity was affected by different O2 concentrations in the gas phase, again supporting the hypothesis of a redox potential dependency, and was decreased by the dispersion of mats with a homogenizer. The loss of activity that occurred from dispersion was partially recovered by the addition of H2, sulfate, and carbon dioxide. These results suggested that the observed activity of nitrogen fixation was related to chemoautotrophic sulfate reducers, and fixation may be active in a limited range of ambient redox potential. Since thermophilic chemosynthetic communities may resemble ancient microbial communities before the appearance of photosynthesis, the present results may be useful when considering the ancient nitrogen cycle on earth.
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Affiliation(s)
- Arisa Nishihara
- Department of Biological Sciences, Tokyo Metropolitan UniversityMinami-Osawa, Hachioji, Tokyo 192–0397Japan
| | - Shin Haruta
- Department of Biological Sciences, Tokyo Metropolitan UniversityMinami-Osawa, Hachioji, Tokyo 192–0397Japan
| | - Shawn E. McGlynn
- Department of Biological Sciences, Tokyo Metropolitan UniversityMinami-Osawa, Hachioji, Tokyo 192–0397Japan
- Earth-Life Science Institute, Tokyo Institute of TechnologyOokayama, Meguro-ku, Tokyo 152–8551Japan
- Biofunctional Catalyst Research Team, RIKEN Center for Sustainable Resource ScienceWako-shi 351–0198Japan
- Blue Marble Space Institute of ScienceSeattle, WA 98145–1561USA
| | - Vera Thiel
- Department of Biological Sciences, Tokyo Metropolitan UniversityMinami-Osawa, Hachioji, Tokyo 192–0397Japan
| | - Katsumi Matsuura
- Department of Biological Sciences, Tokyo Metropolitan UniversityMinami-Osawa, Hachioji, Tokyo 192–0397Japan
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17
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Gonzalez-Martinez A, Muñoz-Palazon B, Rodriguez-Sanchez A, Maza-Márquez P, Mikola A, Gonzalez-Lopez J, Vahala R. Start-up and operation of an aerobic granular sludge system under low working temperature inoculated with cold-adapted activated sludge from Finland. BIORESOURCE TECHNOLOGY 2017; 239:180-189. [PMID: 28521227 DOI: 10.1016/j.biortech.2017.05.037] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 05/04/2017] [Accepted: 05/07/2017] [Indexed: 06/07/2023]
Abstract
An aerobic granular sludge system has been started-up and operated at 7°C temperature using cold-adapted activated sludge as inoculum. The system could form granular biomass due to batch operation allowing for just 5-3min of biomass sedimentation. Scanning electron microscopy showed that fungi helped in the granular biomass formation in the early stages of the granule formation. The removal performance of the system was of 92-95% in BOD5, 75-80% in COD, 70-76% in total nitrogen and 50-60% in total phosphorous. The bacterial community structure from cold-adapted activated sludge changed during the operational time, leading to a final configuration dominated by Microbacteriaceae members Microbacterium and Leucobacter, which were strongly correlated to biomass settling velocity and bioreactor performance, as suggested by multivariate redundancy analyses. This experiment showed that aerobic granular sludge systems could be successfully started-up and operated, with high performance, under low operational temperatures when using cold-adapted biomass as inoculum.
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Affiliation(s)
| | - Barbara Muñoz-Palazon
- Institute of Water Research, University of Granada, C/Ramon y Cajal, 4, 18071 Granada, Spain
| | | | - Paula Maza-Márquez
- Institute of Water Research, University of Granada, C/Ramon y Cajal, 4, 18071 Granada, Spain
| | - Anna Mikola
- Department of Built Environment, University of Aalto, P.O. Box 15200, Aalto, FI-00076 Espoo, Finland
| | - Jesus Gonzalez-Lopez
- Institute of Water Research, University of Granada, C/Ramon y Cajal, 4, 18071 Granada, Spain
| | - Riku Vahala
- Department of Built Environment, University of Aalto, P.O. Box 15200, Aalto, FI-00076 Espoo, Finland
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18
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Huang Z, Zhao F, Li Y, Zhang J, Feng Y. Variations in the bacterial community compositions at different sites in the tomb of Emperor Yang of the Sui Dynasty. Microbiol Res 2016; 196:26-33. [PMID: 28164788 DOI: 10.1016/j.micres.2016.12.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 11/29/2016] [Accepted: 12/07/2016] [Indexed: 11/28/2022]
Abstract
To fully understand the bacterial processes in tomb environments, it is necessary to investigate the details of the bacterial communities present under such oligotrophic conditions. Here, high-throughput sequencing based on partial 16S rRNA gene sequences was used to fully evaluate the bacterial communities at different sites in the tomb of Emperor Yang of the Sui Dynasty. We also aimed to identify the soil factors that were significant related to bacterial diversity and community composition. The results showed the presence of a broad taxonomic diversity that included nine major phyla. Actinobacteria, Firmicutes and Proteobacteria dominated the bacterial profiles in all tomb soil samples. However, significant differences between deposited soils (DS) and covering soils (CSA, CSB and CSC) were revealed by chemistry-based principal component analysis (PCA), the number of OTUs, and the Chao 1 and Shannon indexes. At the family level, hierarchically clustered heatmap and LefSe analyses showed differences in the bacterial community compositions at different sampling sites. Notably, CSA contained significant populations of Nocardioidaceae, Pseudonocardiaceae and Streptomycetaceae, which are often reported to be associated with biodeterioration in cave environments. Further, the most abundant group (>10%) in all soil samples was Streptococcaceae, whose abundance decreased from 34.66% to 13.43% with increasing soil depth. The results of redundancy analysis (RDA) and the Monte Carlo permutation test indicated that soil pH and Cu and Mn levels were significantly related to the bacterial communities in this tomb. This research offers new insight into bacterial communities in cave environments and also provides important information for the protection of this historically important tomb.
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Affiliation(s)
- Zhi Huang
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
| | - Fei Zhao
- Nanjing Institute for Comprehensive utilization of Wild Plants, China CO-OP, Nanjing 210042, China
| | - Yonghui Li
- Key Laboratory of Urban and Architectural Heritage Conservation of Ministry of Education, School of Architecture, Southeast University, Nanjing 210096, China
| | - Jianwei Zhang
- State Key Laboratory Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Youzhi Feng
- State Key Laboratory Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
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19
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Nitrogen fixation in a chemoautotrophic lucinid symbiosis. Nat Microbiol 2016; 2:16193. [PMID: 27775698 DOI: 10.1038/nmicrobiol.2016.193] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 09/07/2016] [Indexed: 02/03/2023]
Abstract
The shallow water bivalve Codakia orbicularis lives in symbiotic association with a sulfur-oxidizing bacterium in its gills. The endosymbiont fixes CO2 and thus generates organic carbon compounds, which support the host's growth. To investigate the uncultured symbiont's metabolism and symbiont-host interactions in detail we conducted a proteogenomic analysis of purified bacteria. Unexpectedly, our results reveal a hitherto completely unrecognized feature of the C. orbicularis symbiont's physiology: the symbiont's genome encodes all proteins necessary for biological nitrogen fixation (diazotrophy). Expression of the respective genes under standard ambient conditions was confirmed by proteomics. Nitrogenase activity in the symbiont was also verified by enzyme activity assays. Phylogenetic analysis of the bacterial nitrogenase reductase NifH revealed the symbiont's close relationship to free-living nitrogen-fixing Proteobacteria from the seagrass sediment. The C. orbicularis symbiont, here tentatively named 'Candidatus Thiodiazotropha endolucinida', may thus not only sustain the bivalve's carbon demands. C. orbicularis may also benefit from a steady supply of fixed nitrogen from its symbiont-a scenario that is unprecedented in comparable chemoautotrophic symbioses.
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20
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Petersen JM, Kemper A, Gruber-Vodicka H, Cardini U, van der Geest M, Kleiner M, Bulgheresi S, Mußmann M, Herbold C, Seah BKB, Antony CP, Liu D, Belitz A, Weber M. Chemosynthetic symbionts of marine invertebrate animals are capable of nitrogen fixation. Nat Microbiol 2016; 2:16195. [PMID: 27775707 PMCID: PMC6872982 DOI: 10.1038/nmicrobiol.2016.195] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 09/07/2016] [Indexed: 12/04/2022]
Abstract
Chemosynthetic symbioses are partnerships between invertebrate animals
and chemosynthetic bacteria. The latter are the primary producers, providing most of
the organic carbon needed for the animal host's nutrition. We sequenced genomes of
the chemosynthetic symbionts from the lucinid bivalve Loripes lucinalis and the stilbonematid nematode Laxus oneistus. The symbionts of both host species
encoded nitrogen fixation genes. This is remarkable as no marine chemosynthetic
symbiont was previously known to be capable of nitrogen fixation. We detected
nitrogenase expression by the symbionts of lucinid clams at the transcriptomic and
proteomic level. Mean stable nitrogen isotope values of Loripes lucinalis were within the range expected for fixed atmospheric
nitrogen, further suggesting active nitrogen fixation by the symbionts. The ability
to fix nitrogen may be widespread among chemosynthetic symbioses in oligotrophic
habitats, where nitrogen availability often limits primary productivity. The chemosynthetic symbionts of the bivalve Loripes lucinalis and nematode Laxus
oneistus are found to encode nitrogen fixation genes, with evidence for
active nitrogen fixation.
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Affiliation(s)
- Jillian M Petersen
- Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, Research Network Chemistry meets Microbiology, University of Vienna, Althanstrasse 14, Vienna 1090, Austria.,Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, Bremen 28359, Germany
| | - Anna Kemper
- Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, Bremen 28359, Germany
| | - Harald Gruber-Vodicka
- Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, Bremen 28359, Germany
| | - Ulisse Cardini
- Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, Research Network Chemistry meets Microbiology, University of Vienna, Althanstrasse 14, Vienna 1090, Austria
| | - Matthijs van der Geest
- Centre for Marine Biodiversity, Exploitation and Conservation (MARBEC), UMR 9190, IRD-IFREMER-CNRS-UM, Université de Montpellier, Montpellier Cedex 5 34095, France.,Department of Coastal Systems and Utrecht University, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands
| | - Manuel Kleiner
- Department of Geoscience, University of Calgary, 2500 University Drive Northwest, Alberta T2N 1N4, Canada
| | - Silvia Bulgheresi
- Archaea Biology and Ecogenomics Division, Department of Ecogenomics and Systems Biology, University of Vienna, Althanstrasse 14, Vienna 1090, Austria
| | - Marc Mußmann
- Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, Research Network Chemistry meets Microbiology, University of Vienna, Althanstrasse 14, Vienna 1090, Austria
| | - Craig Herbold
- Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, Research Network Chemistry meets Microbiology, University of Vienna, Althanstrasse 14, Vienna 1090, Austria
| | - Brandon K B Seah
- Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, Bremen 28359, Germany
| | - Chakkiath Paul Antony
- Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, Bremen 28359, Germany
| | - Dan Liu
- Department of Geoscience, University of Calgary, 2500 University Drive Northwest, Alberta T2N 1N4, Canada
| | - Alexandra Belitz
- Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, Research Network Chemistry meets Microbiology, University of Vienna, Althanstrasse 14, Vienna 1090, Austria
| | - Miriam Weber
- HYDRA Institute for Marine Sciences, Elba Field Station, Campo nell'Elba, Livorno 54037, Italy
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21
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Frank IE, Turk-Kubo KA, Zehr JP. Rapid annotation of nifH gene sequences using classification and regression trees facilitates environmental functional gene analysis. ENVIRONMENTAL MICROBIOLOGY REPORTS 2016; 8:905-916. [PMID: 27557869 DOI: 10.1111/1758-2229.12455] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 08/16/2016] [Indexed: 05/22/2023]
Abstract
The nifH gene is a widely used molecular proxy for studying nitrogen fixation. Phylogenetic classification of nifH gene sequences is an essential step in diazotroph community analysis that requires a fast automated solution due to increasing size of environmental sequence libraries and increasing yield of nifH sequences from high-throughput technologies. A novel approach to rapidly classify nifH amino acid sequences into well-defined phylogenetic clusters that provides a common platform for comparative analysis across studies is presented. Phylogenetic group membership can be accurately predicted with decision tree-type statistical models that identify and utilize signature residues in the amino acid sequences. Our classification models were trained and evaluated with a publicly available and manually curated nifH gene database containing cluster annotations. Model-independent sequence sets from diverse ecosystems were used for further assessment of the models' prediction accuracy. The utility of this novel sequence binning approach was demonstrated in a comparative study where joint treatment of diazotroph assemblages from a wide range of habitats identified habitat-specific and widely-distributed diazotrophs and revealed a marine - terrestrial distinction in community composition. Our rapid and automated phylogenetic cluster assignment circumvents extensive phylogenetic analysis of nifH sequences; hence, it saves substantial time and resources in nitrogen fixation studies.
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Affiliation(s)
- Ildiko E Frank
- Department of Ocean Sciences, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA, 95064, USA
| | - Kendra A Turk-Kubo
- Department of Ocean Sciences, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA, 95064, USA
| | - Jonathan P Zehr
- Department of Ocean Sciences, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA, 95064, USA
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22
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Li ZL, Nan J, Huang C, Liang B, Liu WZ, Cheng HY, Zhang C, Zhang D, Kong D, Kanamaru K, Kobayashi T, Wang AJ, Katayama A. Spatial Abundance and Distribution of Potential Microbes and Functional Genes Associated with Anaerobic Mineralization of Pentachlorophenol in a Cylindrical Reactor. Sci Rep 2016; 6:19015. [PMID: 26750760 PMCID: PMC4707460 DOI: 10.1038/srep19015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 12/02/2015] [Indexed: 01/19/2023] Open
Abstract
Functional interplays of microbial activity, genetic diversity and contaminant transformation are poorly understood in reactors for mineralizing halogenated aromatics anaerobically. Here, we investigated abundance and distribution of potential microbes and functional genes associated with pentachlorophenol (PCP) anaerobic mineralization in a continuous-flow cylindrical reactor (15 cm in length). PCP dechlorination and the metabolite (phenol) were observed at segments 0–8 cm from inlet, where key microbes, including potential reductive dechlorinators (Dehalobacter, Sulfurospirillum, Desulfitobacterium and Desulfovibrio spp.) and phenol degraders (Cryptanaerobacter and Syntrophus spp.), as well as putative functional genes, including putative chlorophenol reductive dehalogenase (cprA) and benzoyl-CoA reductase (bamB), were highly enriched simultaneously. Five types of putative cprAs, three types of putative bamBs and seven types of putative nitrogenase reductase (nifHs) were determined, with their copy numbers decreased gradually from inlet to outlet. Distribution of chemicals, bacteria and putative genes confirmed PCP dechlorination and phenol degradation accomplished in segments 0–5 cm and 0–8 cm, respectively, contributing to a high PCP mineralization rate of 3.86 μM d−1. Through long-term incubation, dechlorination, phenol degradation and nitrogen fixation bacteria coexisted and functioned simultaneously near inlet (0–8 cm), verified the feasibility of anaerobic mineralization of halogenated aromatics in the compact reactor containing multiple functional microbes.
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Affiliation(s)
- Zhi-Ling Li
- State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090 China.,Institute of Materials and Systems for Sustainability, Nagoya University, Chikusa, Nagoya 464-8603 Japan
| | - Jun Nan
- State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090 China
| | - Cong Huang
- State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090 China
| | - Bin Liang
- Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, P.R. China
| | - Wen-Zong Liu
- Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, P.R. China
| | - Hao-Yi Cheng
- Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, P.R. China
| | - Chunfang Zhang
- Institute of Materials and Systems for Sustainability, Nagoya University, Chikusa, Nagoya 464-8603 Japan
| | - Dongdong Zhang
- Institute of Materials and Systems for Sustainability, Nagoya University, Chikusa, Nagoya 464-8603 Japan
| | - Deyong Kong
- State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090 China
| | - Kyoko Kanamaru
- Department of Biological Mechanisms and Functions, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601 Japan
| | - Tetsuo Kobayashi
- Department of Biological Mechanisms and Functions, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601 Japan
| | - Ai-Jie Wang
- State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090 China.,Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, P.R. China
| | - Arata Katayama
- Institute of Materials and Systems for Sustainability, Nagoya University, Chikusa, Nagoya 464-8603 Japan.,Department of Civil Engineering, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603 Japan
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23
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Yilmaz P, Yarza P, Rapp JZ, Glöckner FO. Expanding the World of Marine Bacterial and Archaeal Clades. Front Microbiol 2016; 6:1524. [PMID: 26779174 PMCID: PMC4705458 DOI: 10.3389/fmicb.2015.01524] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 12/18/2015] [Indexed: 12/18/2022] Open
Abstract
Determining which microbial taxa are out there, where they live, and what they are doing is a driving approach in marine microbial ecology. The importance of these questions is underlined by concerted, large-scale, and global ocean sampling initiatives, for example the International Census of Marine Microbes, Ocean Sampling Day, or Tara Oceans. Given decades of effort, we know that the large majority of marine Bacteria and Archaea belong to about a dozen phyla. In addition to the classically culturable Bacteria and Archaea, at least 50 “clades,” at different taxonomic depths, exist. These account for the majority of marine microbial diversity, but there is still an underexplored and less abundant portion remaining. We refer to these hitherto unrecognized clades as unknown, as their boundaries, names, and classifications are not available. In this work, we were able to characterize up to 92 of these unknown clades found within the bacterial and archaeal phylogenetic diversity currently reported for marine water column environments. We mined the SILVA 16S rRNA gene datasets for sequences originating from the marine water column. Instead of the usual subjective taxa delineation and nomenclature methods, we applied the candidate taxonomic unit (CTU) circumscription system, along with a standardized nomenclature to the sequences in newly constructed phylogenetic trees. With this new phylogenetic and taxonomic framework, we performed an analysis of ICoMM rRNA gene amplicon datasets to gain insights into the global distribution of the new marine clades, their ecology, biogeography, and interaction with oceanographic variables. Most of the new clades we identified were interspersed by known taxa with cultivated members, whose genome sequences are available. This result encouraged us to perform metabolic predictions for the novel marine clades using the PICRUSt approach. Our work also provides an update on the taxonomy of several phyla and widely known marine clades as our CTU approach breaks down these randomly lumped clades into smaller objectively calculated subgroups. Finally, all taxa were classified and named following standards compatible with the Bacteriological Code rules, enhancing their digitization, and comparability with future microbial ecological and taxonomy studies.
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Affiliation(s)
- Pelin Yilmaz
- Microbial Genomics and Bioinformatics Research Group, Max Planck Institute for Marine Microbiology Bremen, Germany
| | | | - Josephine Z Rapp
- HGF-MPG Joint Research Group for Deep Sea Ecology and Technology, Max Planck Institute for Marine Microbiology, Bremen and the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research Bremerhaven, Germany
| | - Frank O Glöckner
- Microbial Genomics and Bioinformatics Research Group, Max Planck Institute for Marine MicrobiologyBremen, Germany; Life Sciences and Chemistry, Jacobs UniversityBremen, Germany
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24
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Estrella Alcamán M, Fernandez C, Delgado A, Bergman B, Díez B. The cyanobacterium Mastigocladus fulfills the nitrogen demand of a terrestrial hot spring microbial mat. THE ISME JOURNAL 2015; 9:2290-303. [PMID: 26230049 PMCID: PMC4579480 DOI: 10.1038/ismej.2015.63] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2014] [Revised: 03/23/2015] [Accepted: 03/25/2015] [Indexed: 11/09/2022]
Abstract
Cyanobacteria from Subsection V (Stigonematales) are important components of microbial mats in non-acidic terrestrial hot springs. Despite their diazotrophic nature (N2 fixers), their impact on the nitrogen cycle in such extreme ecosystems remains unknown. Here, we surveyed the identity and activity of diazotrophic cyanobacteria in the neutral hot spring of Porcelana (Northern Patagonia, Chile) during 2009 and 2011-2013. We used 16S rRNA and the nifH gene to analyze the distribution and diversity of diazotrophic cyanobacteria. Our results demonstrate the dominance of the heterocystous genus Mastigocladus (Stigonematales) along the entire temperature gradient of the hot spring (69-38 °C). In situ nitrogenase activity (acetylene reduction), nitrogen fixation rates (cellular uptake of (15)N2) and nifH transcription levels in the microbial mats showed that nitrogen fixation and nifH mRNA expression were light-dependent. Nitrogen fixation activities were detected at temperatures ranging from 58 °C to 46 °C, with maximum daily rates of 600 nmol C2H4 cm(-2) per day and 94.1 nmol N cm(-2) per day. These activity patterns strongly suggest a heterocystous cyanobacterial origin and reveal a correlation between nitrogenase activity and nifH gene expression during diurnal cycles in thermal microbial mats. N and C fixation in the mats contributed ~3 g N m(-2) per year and 27 g C m(-2) per year, suggesting that these vital demands are fully met by the diazotrophic and photoautotrophic capacities of the cyanobacteria in the Porcelana hot spring.
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Affiliation(s)
- María Estrella Alcamán
- Department of Molecular Genetics and Microbiology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Camila Fernandez
- Laboratoire d'Océanographie Microbienne, Observatoire Océanologique, Sorbonne Universités, UPMC Univ Paris 06, UMR 7621, Banyuls/mer, France
- CNRS, UMR 7621, Laboratoire d'Océanographie Microbienne, Observatoire Océanologique, Banyuls/mer, France
- Department of Oceanography, Interdisciplinary Center for Aquaculture Research (INCAR) and COPAS SURAUSTRAL Program, University of Concepción, Concepción, Chile
| | - Antonio Delgado
- Instituto Andaluz de Ciencias de la Tierra (CSIC-Univ. Granada), Armilla, Granada, Spain
| | - Birgitta Bergman
- Department of Ecology, Environment and Plant Sciences and Science for Life Laboratory, Stockholm University, Stockholm, Sweden
| | - Beatriz Díez
- Department of Molecular Genetics and Microbiology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
- Center for Climate and Resilience Research (CR)2, Santiago, Chile
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25
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Cao H, Shao Z, Li J, Zhang W, Qian PY. Phylogenetic diversity of nitrogen-utilizing genes in hydrothermal chimneys from 3 middle ocean ridges. Extremophiles 2015; 19:1173-82. [PMID: 26369648 DOI: 10.1007/s00792-015-0788-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Accepted: 08/30/2015] [Indexed: 10/23/2022]
Abstract
Nitrogen-metabolizing genes, including nitrogenase (nifH), periplasmic nitrate reductase (napA), and cytochrome cd 1-type nitrite reductase (nirS), were collected from hydrothermal chimney sulfides on 3 middle ocean ridges and compared for the first time. There was a clear phylogenetic distinction of these nifH genes between different hydrothermal ecosystems, which supported the colonization and potential adaptation by different nitrogen fixing microbes in those sulfides. In particular, in sulfides from low-temperature hydrothermal vents of the Southwest Indian Ocean Ridge, the prevalence of nifH genes appears to be attributed to sulfate-reducing bacteria, suggesting their ecological significance. Phylogenetic analysis of nitrate/nitrite reductase genes indicated that nitrate was a critical electron acceptor for sulfur- or metal-oxidizing bacteria in these hydrothermal ecosystems. Our results provided information about the compositions and diversity of the 3 important genes involved in nitrogen fixation and nitrate/nitrite reduction processes in hydrothermal ecosystems and is the first comprehensive genetic repertoire of genes related to potential nitrogen fixation and denitrification processes in various hydrothermal environments.
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Affiliation(s)
- Huiluo Cao
- Division of Life Sciences, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
| | - Zongze Shao
- Key Laboratory of Marine Biogenetic Resources, The Third Institute of Oceanography, State of Oceanic Administration, Xiamen, China
| | - Jiangtao Li
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China
| | - Weipeng Zhang
- Division of Life Sciences, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Pei-Yuan Qian
- Division of Life Sciences, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
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26
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A Post-Genomic View of the Ecophysiology, Catabolism and Biotechnological Relevance of Sulphate-Reducing Prokaryotes. Adv Microb Physiol 2015. [PMID: 26210106 DOI: 10.1016/bs.ampbs.2015.05.002] [Citation(s) in RCA: 174] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Dissimilatory sulphate reduction is the unifying and defining trait of sulphate-reducing prokaryotes (SRP). In their predominant habitats, sulphate-rich marine sediments, SRP have long been recognized to be major players in the carbon and sulphur cycles. Other, more recently appreciated, ecophysiological roles include activity in the deep biosphere, symbiotic relations, syntrophic associations, human microbiome/health and long-distance electron transfer. SRP include a high diversity of organisms, with large nutritional versatility and broad metabolic capacities, including anaerobic degradation of aromatic compounds and hydrocarbons. Elucidation of novel catabolic capacities as well as progress in the understanding of metabolic and regulatory networks, energy metabolism, evolutionary processes and adaptation to changing environmental conditions has greatly benefited from genomics, functional OMICS approaches and advances in genetic accessibility and biochemical studies. Important biotechnological roles of SRP range from (i) wastewater and off gas treatment, (ii) bioremediation of metals and hydrocarbons and (iii) bioelectrochemistry, to undesired impacts such as (iv) souring in oil reservoirs and other environments, and (v) corrosion of iron and concrete. Here we review recent advances in our understanding of SRPs focusing mainly on works published after 2000. The wealth of publications in this period, covering many diverse areas, is a testimony to the large environmental, biogeochemical and technological relevance of these organisms and how much the field has progressed in these years, although many important questions and applications remain to be explored.
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27
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Wu Y, Tan L, Liu W, Wang B, Wang J, Cai Y, Lin X. Profiling bacterial diversity in a limestone cave of the western Loess Plateau of China. Front Microbiol 2015; 6:244. [PMID: 25870592 PMCID: PMC4378288 DOI: 10.3389/fmicb.2015.00244] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 03/12/2015] [Indexed: 11/25/2022] Open
Abstract
Bacteria and archaea sustain subsurface cave ecosystems by dominating primary production and fueling biogeochemical cyclings, despite the permanent darkness and shortage of nutrients. However, the heterogeneity and underlying mechanism of microbial diversity in caves, in particular those well connect to surface environment are largely unexplored. In this study, we examined the bacterial abundance and composition in Jinjia Cave, a small and shallow limestone cave located on the western Loess Plateau of China, by enumerating and pyrosequencing small subunit rRNA genes. The results clearly reveal the contrasting bacterial community compositions in relation to cave habitat types, i.e., rock wall deposit, aquatic sediment, and sinkhole soil, which are differentially connected to the surface environment. The deposits on the cave walls were dominated by putative cave-specific bacterial lineages within the γ-Proteobacteria or Actinobacteria that are routinely found on cave rocks around the world. In addition, sequence identity with known functional groups suggests enrichments of chemolithotrophic bacteria potentially involved in autotrophic C fixation and inorganic N transformation on rock surfaces. By contrast, bacterial communities in aquatic sediments were more closely related to those in the overlying soils. This is consistent with the similarity in elemental composition between the cave sediment and the overlying soil, implicating the influence of mineral chemistry on cave microhabitat and bacterial composition. These findings provide compelling molecular evidence of the bacterial community heterogeneity in an East Asian cave, which might be controlled by both subsurface and surface environments.
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Affiliation(s)
- Yucheng Wu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science - Chinese Academy of Sciences, Nanjing China
| | - Liangcheng Tan
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment - Chinese Academy of Sciences, Xi'an China ; State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment - Chinese Academy of Sciences, Xi'an China
| | - Wuxing Liu
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science - Chinese Academy of Sciences, Nanjing China
| | - Baozhan Wang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science - Chinese Academy of Sciences, Nanjing China
| | - Jianjun Wang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology - Chinese Academy of Sciences, Nanjing China
| | - Yanjun Cai
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment - Chinese Academy of Sciences, Xi'an China
| | - Xiangui Lin
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science - Chinese Academy of Sciences, Nanjing China
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28
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Two new Beggiatoa species inhabiting marine mangrove sediments in the Caribbean. PLoS One 2015; 10:e0117832. [PMID: 25689402 PMCID: PMC4331518 DOI: 10.1371/journal.pone.0117832] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Accepted: 12/31/2014] [Indexed: 11/19/2022] Open
Abstract
Beggiatoaceae, giant sulphur-oxidizing bacteria, are well known to occur in cold and temperate waters, as well as hydrothermal vents, where they form dense mats on the floor. However, they have never been described in tropical marine mangroves. Here, we describe two new species of benthic Beggiatoaceae colonizing a marine mangrove adjacent to mangrove roots. We combined phylogenetic and lipid analysis with electron microscopy in order to describe these organisms. Furthermore, oxygen and sulphide measurements in and ex situ were performed in a mesocosm to characterize their environment. Based on this, two new species, Candidatus Maribeggiatoa sp. and Candidatus Isobeggiatoa sp. inhabiting tropical marine mangroves in Guadeloupe were identified. The species identified as Candidatus Maribeggiatoa group suggests that this genus could harbour a third cluster with organisms ranging from 60 to 120 μm in diameter. This is also the first description of an Isobeggiatoa species outside of Arctic and temperate waters. The multiphasic approach also gives information about the environment and indications for the metabolism of these bacteria. Our study shows the widespread occurrence of members of Beggiatoaceae family and provides new insight in their potential role in shallow-water marine sulphide-rich environments such as mangroves.
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