1
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Fortin SG, Sun X, Jayakumar A, Ward BB. Nitrite-oxidizing bacteria adapted to low-oxygen conditions dominate nitrite oxidation in marine oxygen minimum zones. THE ISME JOURNAL 2024; 18:wrae160. [PMID: 39141833 PMCID: PMC11373643 DOI: 10.1093/ismejo/wrae160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2024] [Revised: 07/29/2024] [Accepted: 08/13/2024] [Indexed: 08/16/2024]
Abstract
Nitrite is a central molecule in the nitrogen cycle because nitrite oxidation to nitrate (an aerobic process) retains fixed nitrogen in a system and its reduction to dinitrogen gas (anaerobic) reduces the fixed nitrogen inventory. Despite its acknowledged requirement for oxygen, nitrite oxidation is observed in oxygen-depleted layers of the ocean's oxygen minimum zones (OMZs), challenging the current understanding of OMZ nitrogen cycling. Previous attempts to determine whether nitrite-oxidizing bacteria in the anoxic layer differ from known nitrite oxidizers in the open ocean were limited by cultivation difficulties and sequencing depth. Here, we construct 31 draft genomes of nitrite-oxidizing bacteria from global OMZs. The distribution of nitrite oxidation rates, abundance and expression of nitrite oxidoreductase genes, and relative abundance of nitrite-oxidizing bacterial draft genomes from the same samples all show peaks in the core of the oxygen-depleted zone (ODZ) and are all highly correlated in depth profiles within the major ocean oxygen minimum zones. The ODZ nitrite oxidizers are not found in the Tara Oceans global dataset (the most complete oxic ocean dataset), and the major nitrite oxidizers found in the oxygenated ocean do not occur in ODZ waters. A pangenomic analysis shows the ODZ nitrite oxidizers have distinct gene clusters compared to oxic nitrite oxidizers and are microaerophilic. These findings all indicate the existence of nitrite oxidizers whose niche is oxygen-deficient seawater. Thus, specialist nitrite-oxidizing bacteria are responsible for fixed nitrogen retention in marine oxygen minimum zones, with implications for control of the ocean's fixed nitrogen inventory.
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Affiliation(s)
- Samantha G Fortin
- Department of Geosciences, Princeton University, Princeton, NJ 08544, United States
| | - Xin Sun
- Department of Global Ecology, Carnegie Institution for Science, Stanford, CA 94305, United States
| | - Amal Jayakumar
- Department of Geosciences, Princeton University, Princeton, NJ 08544, United States
| | - Bess B Ward
- Department of Geosciences, Princeton University, Princeton, NJ 08544, United States
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2
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Zhao R, Zhang IH, Jayakumar A, Ward BB, Babbin AR. Age, metabolisms, and potential origin of dominant anammox bacteria in the global oxygen-deficient zones. ISME COMMUNICATIONS 2024; 4:ycae060. [PMID: 38770059 PMCID: PMC11104535 DOI: 10.1093/ismeco/ycae060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 04/11/2024] [Accepted: 04/19/2024] [Indexed: 05/22/2024]
Abstract
Anammox bacteria inhabiting oxygen-deficient zones (ODZs) are a major functional group mediating fixed nitrogen loss in the global ocean. However, many basic questions regarding the diversity, broad metabolisms, origin, and adaptive mechanisms of ODZ anammox bacteria remain unaddressed. Here we report two novel metagenome-assembled genomes of anammox bacteria affiliated with the Scalindua genus, which represent most, if not all, of the anammox bacteria in the global ODZs. Metagenomic read-recruiting and comparison with historical data show that they are ubiquitously present in all three major ODZs. Beyond the core anammox metabolism, both organisms contain cyanase, and the more dominant one encodes a urease, indicating most ODZ anammox bacteria can utilize cyanate and urea in addition to ammonium. Molecular clock analysis suggests that the evolutionary radiation of these bacteria into ODZs occurred no earlier than 310 million years ago, ~1 billion years after the emergence of the earliest modern-type ODZs. Different strains of the ODZ Scalindua species are also found in benthic sediments, and the first ODZ Scalindua is likely derived from the benthos. Compared to benthic strains of the same clade, ODZ Scalindua uniquely encodes genes for urea utilization but has lost genes related to growth arrest, flagellum synthesis, and chemotaxis, presumably for adaptation to thrive in the global ODZ waters. Our findings expand the known metabolisms and evolutionary history of the bacteria controlling the global nitrogen budget.
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Affiliation(s)
- Rui Zhao
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Irene H Zhang
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Amal Jayakumar
- Department of Geosciences, Princeton University, Princeton, NJ 08544, United States
| | - Bess B Ward
- Department of Geosciences, Princeton University, Princeton, NJ 08544, United States
| | - Andrew R Babbin
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
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3
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Wan XS, Sheng HX, Liu L, Shen H, Tang W, Zou W, Xu MN, Zheng Z, Tan E, Chen M, Zhang Y, Ward BB, Kao SJ. Particle-associated denitrification is the primary source of N 2O in oxic coastal waters. Nat Commun 2023; 14:8280. [PMID: 38092778 PMCID: PMC10719265 DOI: 10.1038/s41467-023-43997-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 11/27/2023] [Indexed: 12/17/2023] Open
Abstract
The heavily human-perturbed coastal oceans are hotspots of nitrous oxide (N2O) emission to the atmosphere. The processes underpinning the N2O flux, however, remain poorly understood, leading to large uncertainties in assessing global N2O budgets. Using a suite of nitrogen isotope labeling experiments, we show that multiple processes contribute to N2O production throughout the estuarine-coastal gradient, sustaining intensive N2O flux to the atmosphere. Unexpectedly, denitrification, rather than ammonia oxidation as previously assumed, constitutes the major source of N2O in well-oxygenated coastal waters. Size-fractionated manipulation experiments with gene analysis further reveal niche partitioning of ammonia oxidizers and denitrifiers across the particle size spectrum; denitrification dominated on large particles and ammonia oxidizers on small particles. Total N2O production rate increases with substrate and particle concentrations, suggesting a crucial interplay between nutrients and particles in controlling N2O production. The controlling factors identified here may help understand climate feedback mechanisms between human activity and coastal oceans.
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Affiliation(s)
- Xianhui S Wan
- College of Ocean and Earth Sciences, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, 361102, China.
- Department of Geosciences, Princeton University, Princeton, NJ, 08544, USA.
| | - Hua-Xia Sheng
- College of Ocean and Earth Sciences, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, 361102, China
| | - Li Liu
- College of Ocean and Earth Sciences, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, 361102, China
| | - Hui Shen
- College of Ocean and Earth Sciences, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, 361102, China
| | - Weiyi Tang
- Department of Geosciences, Princeton University, Princeton, NJ, 08544, USA
| | - Wenbin Zou
- College of Ocean and Earth Sciences, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, 361102, China
| | - Min N Xu
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, 570208, China
| | - Zhenzhen Zheng
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, 570208, China
| | - Ehui Tan
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, 570208, China
| | - Mingming Chen
- College of Ocean and Earth Sciences, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, 361102, China
| | - Yao Zhang
- College of Ocean and Earth Sciences, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, 361102, China
| | - Bess B Ward
- Department of Geosciences, Princeton University, Princeton, NJ, 08544, USA
| | - Shuh-Ji Kao
- College of Ocean and Earth Sciences, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, 361102, China.
- State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, 570208, China.
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4
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Chen B, Yu K, Fu L, Wei Y, Liang J, Liao Z, Qin Z, Yu X, Deng C, Han M, Ma H. The diversity, community dynamics, and interactions of the microbiome in the world's deepest blue hole: insights into extreme environmental response patterns and tolerance of marine microorganisms. Microbiol Spectr 2023; 11:e0053123. [PMID: 37861344 PMCID: PMC10883803 DOI: 10.1128/spectrum.00531-23] [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: 02/03/2023] [Accepted: 09/08/2023] [Indexed: 10/21/2023] Open
Abstract
IMPORTANCE This study comprehensively examined the community dynamics, functional profiles, and interactions of the microbiome in the world's deepest blue hole. The findings revealed a positive correlation between the α-diversities of Symbiodiniaceae and archaea, indicating the potential reliance of Symbiodiniaceae on archaea in an extreme environment resulting from a partial niche overlap. The negative association between the α-diversity and β-diversity of the bacterial community suggested that the change rule of the bacterial community was consistent with the Anna Karenina effects. The core microbiome comprised nine microbial taxa, highlighting their remarkable tolerance and adaptability to sharp environmental gradient variations. Bacteria and archaea played significant roles in carbon, nitrogen, and sulfur cycles, while fungi contributed to carbon metabolism. This study advanced our understanding of the community dynamics, response patterns, and resilience of microorganisms populating the world's deepest blue hole, thereby facilitating further ecological and evolutional exploration of microbiomes in diverse extreme environments.
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Affiliation(s)
- Biao Chen
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University , Nanning, China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) , Zhuhai, China
| | - Kefu Yu
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University , Nanning, China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) , Zhuhai, China
| | - Liang Fu
- Sansha Track Ocean Coral Reef Conservation Research Institute Co. Ltd. , Qionghai, China
| | - Yuxin Wei
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University , Nanning, China
| | - Jiayuan Liang
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University , Nanning, China
| | - Zhiheng Liao
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University , Nanning, China
- Key Laboratory of Environmental Change and Resource Use in Beibu Gulf, Ministry of Education, Nanning Normal University , Nanning, China
| | - Zhenjun Qin
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University , Nanning, China
| | - Xiaopeng Yu
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University , Nanning, China
| | - Chuanqi Deng
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University , Nanning, China
| | - Minwei Han
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University , Nanning, China
| | - Honglin Ma
- Key Laboratory of Environmental Change and Resource Use in Beibu Gulf, Ministry of Education, Nanning Normal University , Nanning, China
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5
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Ciccarese D, Tantawi O, Zhang IH, Plata D, Babbin AR. Microscale dynamics promote segregated denitrification in diatom aggregates sinking slowly in bulk oxygenated seawater. COMMUNICATIONS EARTH & ENVIRONMENT 2023; 4:275. [PMID: 38665198 PMCID: PMC11041763 DOI: 10.1038/s43247-023-00935-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 07/18/2023] [Indexed: 04/28/2024]
Abstract
Sinking marine particles drive the biological pump that naturally sequesters carbon from the atmosphere. Despite their small size, the compartmentalized nature of particles promotes intense localized metabolic activity by their bacterial colonizers. Yet the mechanisms promoting the onset of denitrification, a metabolism that arises once oxygen is limiting, remain to be established. Here we show experimentally that slow sinking aggregates composed of marine diatoms-important primary producers for global carbon export-support active denitrification even among bulk oxygenated water typically thought to exclude anaerobic metabolisms. Denitrification occurs at anoxic microsites distributed throughout a particle and within microns of a particle's boundary, and fluorescence-reporting bacteria show nitrite can be released into the water column due to segregated dissimilatory reduction of nitrate and nitrite. Examining intact and broken diatoms as organic sources, we show slowly leaking cells promote more bacterial growth, allow particles to have lower oxygen, and generally support greater denitrification.
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Affiliation(s)
- Davide Ciccarese
- Department of Earth, Atmospheric & Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA USA
| | - Omar Tantawi
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA USA
| | - Irene H. Zhang
- Department of Earth, Atmospheric & Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA USA
- Program in Microbiology, Massachusetts Institute of Technology, Cambridge, MA USA
| | - Desiree Plata
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA USA
| | - Andrew R. Babbin
- Department of Earth, Atmospheric & Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA USA
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6
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Zhang IH, Sun X, Jayakumar A, Fortin SG, Ward BB, Babbin AR. Partitioning of the denitrification pathway and other nitrite metabolisms within global oxygen deficient zones. ISME COMMUNICATIONS 2023; 3:76. [PMID: 37474642 PMCID: PMC10359470 DOI: 10.1038/s43705-023-00284-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 07/05/2023] [Accepted: 07/11/2023] [Indexed: 07/22/2023]
Abstract
Oxygen deficient zones (ODZs) account for about 30% of total oceanic fixed nitrogen loss via processes including denitrification, a microbially mediated pathway proceeding stepwise from NO3- to N2. This process may be performed entirely by complete denitrifiers capable of all four enzymatic steps, but many organisms possess only partial denitrification pathways, either producing or consuming key intermediates such as the greenhouse gas N2O. Metagenomics and marker gene surveys have revealed a diversity of denitrification genes within ODZs, but whether these genes co-occur within complete or partial denitrifiers and the identities of denitrifying taxa remain open questions. We assemble genomes from metagenomes spanning the ETNP and Arabian Sea, and map these metagenome-assembled genomes (MAGs) to 56 metagenomes from all three major ODZs to reveal the predominance of partial denitrifiers, particularly single-step denitrifiers. We find niche differentiation among nitrogen-cycling organisms, with communities performing each nitrogen transformation distinct in taxonomic identity and motility traits. Our collection of 962 MAGs presents the largest collection of pelagic ODZ microorganisms and reveals a clearer picture of the nitrogen cycling community within this environment.
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Affiliation(s)
- Irene H Zhang
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Program in Microbiology, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Xin Sun
- Department of Global Ecology, Carnegie Institution for Science, Stanford, CA, USA
- Department of Geosciences, Princeton University, Princeton, NJ, USA
| | - Amal Jayakumar
- Department of Geosciences, Princeton University, Princeton, NJ, USA
| | | | - Bess B Ward
- Department of Geosciences, Princeton University, Princeton, NJ, USA
| | - Andrew R Babbin
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
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7
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Anstett J, Plominsky AM, DeLong EF, Kiesser A, Jürgens K, Morgan-Lang C, Stepanauskas R, Stewart FJ, Ulloa O, Woyke T, Malmstrom R, Hallam SJ. A compendium of bacterial and archaeal single-cell amplified genomes from oxygen deficient marine waters. Sci Data 2023; 10:332. [PMID: 37244914 DOI: 10.1038/s41597-023-02222-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 05/10/2023] [Indexed: 05/29/2023] Open
Abstract
Oxygen-deficient marine waters referred to as oxygen minimum zones (OMZs) or anoxic marine zones (AMZs) are common oceanographic features. They host both cosmopolitan and endemic microorganisms adapted to low oxygen conditions. Microbial metabolic interactions within OMZs and AMZs drive coupled biogeochemical cycles resulting in nitrogen loss and climate active trace gas production and consumption. Global warming is causing oxygen-deficient waters to expand and intensify. Therefore, studies focused on microbial communities inhabiting oxygen-deficient regions are necessary to both monitor and model the impacts of climate change on marine ecosystem functions and services. Here we present a compendium of 5,129 single-cell amplified genomes (SAGs) from marine environments encompassing representative OMZ and AMZ geochemical profiles. Of these, 3,570 SAGs have been sequenced to different levels of completion, providing a strain-resolved perspective on the genomic content and potential metabolic interactions within OMZ and AMZ microbiomes. Hierarchical clustering confirmed that samples from similar oxygen concentrations and geographic regions also had analogous taxonomic compositions, providing a coherent framework for comparative community analysis.
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Affiliation(s)
- Julia Anstett
- Graduate Program in Genome Sciences and Technology, Genome Sciences Centre, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada
| | - Alvaro M Plominsky
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, 92037, USA
| | - Edward F DeLong
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, University of Hawaii, Manoa, Honolulu, HI, 96822, USA
| | - Alyse Kiesser
- School of Engineering, The University of British Columbia, Kelowna, BC, Canada
| | - Klaus Jürgens
- Leibniz Institute for Baltic Sea Research, Warnemünde, Germany
| | - Connor Morgan-Lang
- Graduate Program in Bioinformatics, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | | | - Frank J Stewart
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA
- Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, GA, USA
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, USA
| | - Osvaldo Ulloa
- Departamento de Oceanografía, Universidad de Concepción, Casilla 160-C, 4070386, Concepción, Chile
- Instituto Milenio de Oceanografía, Casilla 1313, 4070386, Concepción, Chile
| | - Tanja Woyke
- Department of Energy Joint Genome Institute, Berkeley, CA, USA
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Rex Malmstrom
- Department of Energy Joint Genome Institute, Berkeley, CA, USA
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Steven J Hallam
- Graduate Program in Genome Sciences and Technology, Genome Sciences Centre, University of British Columbia, Vancouver, British Columbia, Canada.
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada.
- Graduate Program in Bioinformatics, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
- Life Sciences Institute, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada.
- ECOSCOPE Training Program, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada.
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8
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Dick JM, Tan J. Chemical Links Between Redox Conditions and Estimated Community Proteomes from 16S rRNA and Reference Protein Sequences. MICROBIAL ECOLOGY 2023; 85:1338-1355. [PMID: 35503575 DOI: 10.1007/s00248-022-01988-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 02/28/2022] [Indexed: 05/10/2023]
Abstract
Environmental influences on community structure are often assessed through multivariate analyses in order to relate microbial abundances to separately measured physicochemical variables. However, genes and proteins are themselves chemical entities; in combination with genome databases, differences in microbial abundances directly encode for chemical variability. We predicted that the carbon oxidation state of estimated community proteomes, obtained by combining taxonomic abundances from published 16S rRNA gene sequencing datasets with reference microbial proteomes from the NCBI Reference Sequence (RefSeq) database, would reflect environmental oxidation-reduction conditions. Analysis of multiple datasets confirms the geobiochemical predictions for environmental redox gradients in hydrothermal systems, stratified lakes and marine environments, and shale gas wells. The geobiochemical signal is largest for the steep redox gradients associated with hydrothermal systems and between injected water and produced fluids from shale gas wells, demonstrating that microbial community composition can be a chemical proxy for environmental redox gradients. Although estimates of oxidation state from 16S amplicon and metagenomic sequences are correlated, the 16S-based estimates show stronger associations with redox gradients in some environments.
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Affiliation(s)
- Jeffrey M Dick
- Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Ministry of Education, School of Geosciences and Info-Physics, Central South University, Changsha, 410083, China.
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.
| | - Jingqiang Tan
- Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Ministry of Education, School of Geosciences and Info-Physics, Central South University, Changsha, 410083, China
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9
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Geller-McGrath D, Mara P, Taylor GT, Suter E, Edgcomb V, Pachiadaki M. Diverse secondary metabolites are expressed in particle-associated and free-living microorganisms of the permanently anoxic Cariaco Basin. Nat Commun 2023; 14:656. [PMID: 36746960 PMCID: PMC9902471 DOI: 10.1038/s41467-023-36026-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 01/12/2023] [Indexed: 02/08/2023] Open
Abstract
Secondary metabolites play essential roles in ecological interactions and nutrient acquisition, and are of interest for their potential uses in medicine and biotechnology. Genome mining for biosynthetic gene clusters (BGCs) can be used for the discovery of new compounds. Here, we use metagenomics and metatranscriptomics to analyze BGCs in free-living and particle-associated microbial communities through the stratified water column of the Cariaco Basin, Venezuela. We recovered 565 bacterial and archaeal metagenome-assembled genomes (MAGs) and identified 1154 diverse BGCs. We show that differences in water redox potential and microbial lifestyle (particle-associated vs. free-living) are associated with variations in the predicted composition and production of secondary metabolites. Our results indicate that microbes, including understudied clades such as Planctomycetota, potentially produce a wide range of secondary metabolites in these anoxic/euxinic waters.
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Affiliation(s)
| | - Paraskevi Mara
- Geology & Geophysics Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - Gordon T Taylor
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, USA
| | - Elizabeth Suter
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, USA
- Biology, Chemistry and Environmental Studies Department, Molloy College, Rockville Centre, NY, USA
| | - Virginia Edgcomb
- Geology & Geophysics Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA.
| | - Maria Pachiadaki
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA.
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10
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Liu SJ, Xie ZX, Wu PF, Zheng RW, Liu Y, Lin L, Liu HP, Wang DZ. Composition and assembly of the bacterial community in the overlying waters of the coral reef of China's Xisha Islands. Front Microbiol 2022; 13:1059262. [PMID: 36590395 PMCID: PMC9797850 DOI: 10.3389/fmicb.2022.1059262] [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: 10/01/2022] [Accepted: 11/30/2022] [Indexed: 12/23/2022] Open
Abstract
Coral reef ecosystems are one of the most diverse and productive habitats on Earth. Microbes in the reef-overlying waters are key players in maintaining this ecosystem through regulating biogeochemical and ecological processes. However, the composition structure and assembly mechanism of microbial community in the reef-overlying waters remain largely unknown. In the present study, the bacterial communities from the overlying waters of atolls and fringing reefs as well as the surface waters of the adjacent open ocean of the Xisha Islands in the South China Sea were investigated using 16S rRNA high-throughput sequencing combined with a size-fractionation strategy. The results showed that environments of all sampling stations were similar, characterized by an almost complete lack of inorganic nutrients such as nitrogen and phosphorus. Proteobacteria, Cyanobacteria and Bacteroidetes were the dominant phyla, and Synechococcus was most abundant at the genus level in both large fraction (LF; 1.6-200 μm) and small fraction (SF; 0.2-1.6 μm) communities. Only a slight difference in community composition between LF and SF samples was observed. The bacterial communities among the three habitat types showed noticeable differences, and the bacterial composition among the atoll reefs was more varied than that among the fringing reefs. The similarity of bacterial communities significantly declined with the increasing geographic distance, and stochastic processes were more important than deterministic processes in bacterial community assembly. This study sheds lights on the bacterial biodiversity of coral reefs and the importance of stochastic process in structuring bacterial communities.
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Affiliation(s)
- Si-Jia Liu
- State Key Laboratory of Marine Environmental Science, College of the Environment and Ecology, Xiamen University, Xiamen, China
| | - Zhang-Xian Xie
- State Key Laboratory of Marine Environmental Science, College of the Environment and Ecology, Xiamen University, Xiamen, China,Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Zhuhai, China
| | - Peng-Fei Wu
- State Key Laboratory of Marine Environmental Science, College of the Environment and Ecology, Xiamen University, Xiamen, China
| | - Ru-Wen Zheng
- State Key Laboratory of Marine Environmental Science, College of the Environment and Ecology, Xiamen University, Xiamen, China
| | - Yuan Liu
- State Key Laboratory of Marine Environmental Science, College of the Environment and Ecology, Xiamen University, Xiamen, China
| | - Lin Lin
- State Key Laboratory of Marine Environmental Science, College of the Environment and Ecology, Xiamen University, Xiamen, China,Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Zhuhai, China
| | - Hai-Peng Liu
- State Key Laboratory of Marine Environmental Science, College of Ocean & Earth Science, Xiamen University, Xiamen, China
| | - Da-Zhi Wang
- State Key Laboratory of Marine Environmental Science, College of the Environment and Ecology, Xiamen University, Xiamen, China,Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Zhuhai, China,*Correspondence: Da-Zhi Wang,
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11
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Duan L, Li JL, Yin LZ, Luo XQ, Ahmad M, Fang BZ, Li SH, Deng QQ, Wang P, Li WJ. Habitat-dependent prokaryotic microbial community, potential keystone species, and network complexity in a subtropical estuary. ENVIRONMENTAL RESEARCH 2022; 212:113376. [PMID: 35561827 DOI: 10.1016/j.envres.2022.113376] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 03/09/2022] [Accepted: 04/25/2022] [Indexed: 06/15/2023]
Abstract
Microbes (e.g., bacteria and archaea) are indispensable components for the key biological processes of estuarine ecosystems and three main habitats (sediment, particle, and water) are harboring diverse estuarine microbes. However, we still know little about how the microbial community structures, potential keystone species, and network properties change among these three habitats in estuarine ecosystems. In this study, we collected size-fractioned water and sediment samples from the Pearl River Estuary to reveal their microbial diversity, community structures, network properties, and potential keystone taxa. We found that the sediment microbial community was remarkably more diverse than particle-attached (PA) and free-living (FL) communities, whereas its ecological network was less complex in terms of node distance and connectivity. TOC was determined as the main driver of sediment community, while the PA and FL communities were predominantly shaped by NO2-, non-ionic ammonia (NH) and pH. Among the bulk water, there were no significant differences between PA and FL communities in diversity, community structure, and network complexity. However, the PA community was more susceptible to metal elements, suggesting their higher level of involvement in physiological metabolism. Potential keystone taxa among community networks were taxonomically divergent in three habitats. Specifically, Synechococcales (Cyanobacteria) and Actinomarinales (Actinobacteria) exclusively served as the module-hubs in FL network, while members from phylum Proteobacteria and Bacteroidetes were the module-hubs and connectors in PA network. Potential keystone taxa in sediment network were more diverse and covered 9 phyla, including the only archaeal lineage Bathyarchaeia (Crenarchaeota). Overall, our study provided more detailed information about estuarine microbial communities in three habitats, especially the potential keystone species, which provided new perspectives on evaluating further effects of anthropogenic disturbances on estuarine microbes and facilitated the environment monitoring based on microbial community.
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Affiliation(s)
- Li Duan
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Jia-Ling Li
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Ling-Zi Yin
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Xiao-Qing Luo
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Manzoor Ahmad
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Bao-Zhu Fang
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
| | - Shan-Hui Li
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Qi-Qi Deng
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Pandeng Wang
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China; Hubei Key Laboratory of Marine Geological Resources, China University of Geosciences, Wuhan 430074, China; School of Ecology, Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, China.
| | - Wen-Jun Li
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China; State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China.
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12
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Insights into Prokaryotic Community and Its Potential Functions in Nitrogen Metabolism in the Bay of Bengal, a Pronounced Oxygen Minimum Zone. Microbiol Spectr 2022; 10:e0089221. [PMID: 35579458 PMCID: PMC9241787 DOI: 10.1128/spectrum.00892-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ocean oxygen minimum zones (OMZs) around the global ocean are expanding both horizontally and vertically. Multiple studies have identified the significant influence of anoxic conditions (≤1 μM O2) on marine prokaryotic communities and biogeochemical cycling of elements. However, little attention has been paid to the expanding low-oxygen zones where the oxygen level is still above the anoxic level. Here, we studied the abundance and taxonomic and functional profiles of prokaryotic communities in the Bay of Bengal (BoB), where the oxygen concentration is barely above suboxic level (5 μM O2). We found the sinking of Trichodesmium into deep water was far more efficient than that of Prochlorococcus, suggesting Trichodesmium blooms might be an essential carbon and nitrogen source for the maintenance of the BoB OMZ. In addition to the shift in the prokaryotic community composition, the abundance of some functional genes also changed with the change of oxygen concentration. Compared to oxic (>60 μM O2) Tara Ocean and high-hypoxic (>20 to ≤60 μM O2) BoB samples, we found more SAR11-nar sequences (responsible for reducing nitrate to nitrite) in low-hypoxic (>5 to ≤20 μM O2) BoB waters. This suggested SAR11-nar genes would be more widespread due to the expansion of OMZs. It seems that the nitrite-N was not further reduced to nitrogen through denitrification but likely oxidized to nitrate by Nitrospinae in the BoB OMZ and then accumulated in the form of nitrate-N. However, the lack of N2 production in the BoB would change if the BoB OMZ became anoxic. Together, these results suggested that reduction of oxygen concentration and OMZ expansion may increase the use of nitrate by SAR11 and N2 production in the BoB. IMPORTANCE Recognizing the prokaryotic community and its functions in hypoxic (>5 to ≤60 μM O2) environments before further expansion of OMZs is critical. We demonstrate the prokaryotic community and its potential functions in nitrogen metabolism in the Bay of Bengal (BoB), where oxygen concentration is barely above suboxic level. This study highlighted that Trichodesmium might be an essential carbon and nitrogen source in the maintenance of the BoB OMZ. Additionally, we suggest that the lack of N2 production in the BoB would change if the BoB OMZ became anoxic, and the expansion of OMZs in the global ocean may potentially increase the use of nitrate by SAR11.
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13
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Steinsdóttir HGR, Gómez‐Ramírez E, Mhatre S, Schauberger C, Bertagnolli AD, Pratte ZA, Stewart FJ, Thamdrup B, Bristow LA. Anaerobic methane oxidation in a coastal oxygen minimum zone: spatial and temporal dynamics. Environ Microbiol 2022; 24:2361-2379. [PMID: 35415879 PMCID: PMC9323439 DOI: 10.1111/1462-2920.16003] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 04/05/2022] [Accepted: 04/05/2022] [Indexed: 11/28/2022]
Abstract
Coastal waters are a major source of marine methane to the atmosphere. Particularly high concentrations of this potent greenhouse gas are found in anoxic waters, but it remains unclear if and to what extent anaerobic methanotrophs mitigate the methane flux. Here we investigate the long-term dynamics in methanotrophic activity and the methanotroph community in the coastal oxygen minimum zone (OMZ) of Golfo Dulce, Costa Rica, combining biogeochemical analyses, experimental incubations and 16S rRNA gene sequencing over 3 consecutive years. Our results demonstrate a stable redox zonation across the years with high concentrations of methane (up to 1.7 μmol L-1 ) in anoxic bottom waters. However, we also measured high activities of anaerobic methane oxidation in the OMZ core (rate constant, k, averaging 30 yr-1 in 2018 and 8 yr-1 in 2019-2020). The OPU3 and Deep Sea-1 clades of the Methylococcales were implicated as conveyors of the activity, peaking in relative abundance 5-25 m below the oxic-anoxic interface and in the deep anoxic water respectively. Although their genetic capacity for anaerobic methane oxidation remains unexplored, their sustained high relative abundance indicates an adaptation of these clades to the anoxic, methane-rich OMZ environment, allowing them to play major roles in mitigating methane fluxes.
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Affiliation(s)
| | | | - Snehit Mhatre
- Department of BiologyUniversity of Southern DenmarkOdenseDenmark
| | | | | | - Zoe A. Pratte
- Department of Microbiology and Cell BiologyMontana State UniversityBozemanMTUSA
| | - Frank J. Stewart
- Department of Microbiology and Cell BiologyMontana State UniversityBozemanMTUSA
- School of Biological SciencesCenter for Microbial Dynamics and Infection, Georgia Institute of TechnologyAtlantaGAUSA
| | - Bo Thamdrup
- Department of BiologyUniversity of Southern DenmarkOdenseDenmark
| | - Laura A. Bristow
- Department of BiologyUniversity of Southern DenmarkOdenseDenmark
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14
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Viral community analysis in a marine oxygen minimum zone indicates increased potential for viral manipulation of microbial physiological state. THE ISME JOURNAL 2022; 16:972-982. [PMID: 34743175 PMCID: PMC8940887 DOI: 10.1038/s41396-021-01143-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 10/11/2021] [Accepted: 10/13/2021] [Indexed: 11/08/2022]
Abstract
Microbial communities in oxygen minimum zones (OMZs) are known to have significant impacts on global biogeochemical cycles, but viral influence on microbial processes in these regions are much less studied. Here we provide baseline ecological patterns using microscopy and viral metagenomics from the Eastern Tropical North Pacific (ETNP) OMZ region that enhance our understanding of viruses in these climate-critical systems. While extracellular viral abundance decreased below the oxycline, viral diversity and lytic infection frequency remained high within the OMZ, demonstrating that viral influences on microbial communities were still substantial without the detectable presence of oxygen. Viral community composition was strongly related to oxygen concentration, with viral populations in low-oxygen portions of the water column being distinct from their surface layer counterparts. However, this divergence was not accompanied by the expected differences in viral-encoded auxiliary metabolic genes (AMGs) relating to nitrogen and sulfur metabolisms that are known to be performed by microbial communities in these low-oxygen and anoxic regions. Instead, several abundant AMGs were identified in the oxycline and OMZ that may modulate host responses to low-oxygen stress. We hypothesize that this is due to selection for viral-encoded genes that influence host survivability rather than modulating host metabolic reactions within the ETNP OMZ. Together, this study shows that viruses are not only diverse throughout the water column in the ETNP, including the OMZ, but their infection of microorganisms has the potential to alter host physiological state within these biogeochemically important regions of the ocean.
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15
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Suzzi AL, Gaston TF, McKenzie L, Mazumder D, Huggett MJ. Tracking the impacts of nutrient inputs on estuary ecosystem function. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 811:152405. [PMID: 34923003 DOI: 10.1016/j.scitotenv.2021.152405] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 12/10/2021] [Accepted: 12/10/2021] [Indexed: 06/14/2023]
Abstract
Estuaries are one of the most impacted coastal environments globally, subjected to multiple stressors from urban, industry and coastal development. With increasing anthropogenic activity surrounding estuarine systems, sewage inputs have become a common concern. Stable isotope analysis provides a well-established tool to investigate the incorporation of nitrogen into marine organisms and identify major nutrient sources. Benthic macroinvertebrate communities are often used as bioindicators in ecological studies as they typically display predictable responses to anthropogenic pressures, however have a suite of limitations and costs associated with their use. 16S rDNA amplicon sequencing techniques allow for investigation of the microbial communities inhabiting complex environmental samples, with potential as a tool in the ecological assessment of pollution. These communities have not yet been adequately considered for ecological studies and biomonitoring, with a need to better understand interactions with environmental stressors and implications for ecosystem function. This study used a combination of stable isotope analysis to trace the uptake of anthropogenic nitrogen in biota, traditional assessment of benthic macroinvertebrate communities, and 16S rDNA genotyping of benthic microbial communities. Stable isotope analysis of seagrass and epiphytes identified multiple treated and untreated sewage inputs, ranges of 5.2-7.2‰ and 1.9-4.0‰ for δ15N respectively, as the dominant nitrogen source at specific locations. The benthic macroinvertebrate community reflected these inputs with shifts in dominant taxa and high abundances of polychaetes at some sites. Microbial communities provided a sensitive indication of impact with a breadth of information not available using traditional techniques. Composition and predicted function reflected sewage inputs, particularly within sediments, with the relative abundance of specific taxa and putative pathogens linked to these inputs. This research supports the growing body of evidence that benthic microbial communities respond rapidly to anthropogenic stressors and have potential as a monitoring tool in urban estuarine systems.
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Affiliation(s)
- Alessandra L Suzzi
- College of Engineering, Science and Environment, University of Newcastle, Ourimbah, NSW, Australia.
| | - Troy F Gaston
- College of Engineering, Science and Environment, University of Newcastle, Ourimbah, NSW, Australia
| | - Louise McKenzie
- College of Engineering, Science and Environment, University of Newcastle, Ourimbah, NSW, Australia; Hunter Water Corporation, Newcastle, NSW, Australia
| | - Debashish Mazumder
- Australian Nuclear Science and Technology Organisation (ANSTO), Sydney, NSW, Australia
| | - Megan J Huggett
- College of Engineering, Science and Environment, University of Newcastle, Ourimbah, NSW, Australia; Centre for Marine Ecosystems Research, School of Science, Edith Cowan University, Joondalup, WA, Australia
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16
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The marine nitrogen cycle: new developments and global change. Nat Rev Microbiol 2022; 20:401-414. [PMID: 35132241 DOI: 10.1038/s41579-022-00687-z] [Citation(s) in RCA: 51] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/07/2022] [Indexed: 12/25/2022]
Abstract
The ocean is home to a diverse and metabolically versatile microbial community that performs the complex biochemical transformations that drive the nitrogen cycle, including nitrogen fixation, assimilation, nitrification and nitrogen loss processes. In this Review, we discuss the wealth of new ocean nitrogen cycle research in disciplines from metaproteomics to global biogeochemical modelling and in environments from productive estuaries to the abyssal deep sea. Influential recent discoveries include new microbial functional groups, novel metabolic pathways, original conceptual perspectives and ground-breaking analytical capabilities. These emerging research directions are already contributing to urgent efforts to address the primary challenge facing marine microbiologists today: the unprecedented onslaught of anthropogenic environmental change on marine ecosystems. Ocean warming, acidification, nutrient enrichment and seawater stratification have major effects on the microbial nitrogen cycle, but widespread ocean deoxygenation is perhaps the most consequential for the microorganisms involved in both aerobic and anaerobic nitrogen transformation pathways. In turn, these changes feed back to the global cycles of greenhouse gases such as carbon dioxide and nitrous oxide. At a time when our species casts a lengthening shadow across all marine ecosystems, timely new advances offer us unique opportunities to understand and better predict human impacts on nitrogen biogeochemistry in the changing ocean of the Anthropocene.
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17
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Zhang R, Xu X, Jia D, Lyu Y, Hu J, Chen Q, Sun W. Sediments alleviate the inhibition effects of antibiotics on denitrification: Functional gene, microbial community, and antibiotic resistance gene analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 804:150092. [PMID: 34520908 DOI: 10.1016/j.scitotenv.2021.150092] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/28/2021] [Accepted: 08/29/2021] [Indexed: 06/13/2023]
Abstract
Both antibiotics and sediments can affect the denitrification in aquatic systems. However, little is known how antibiotics influence the denitrification in the presence of sediments. Here, the effects of antibiotics (sulfamethoxazole, tetracycline and ofloxacin) on denitrification in the absence and presence of sediments were investigated. The influencing mechanisms were revealed by quantifying the denitrification functional genes (DNGs), 16S-seq of bacteria, and antibiotic resistance genes (ARGs). The results showed that the presence of antibiotics inhibited NO3-N reduction by decreasing the abundances of narG, nirK, nosZ, total DNGs, and denitrifying bacteria. However, the inhibition effect was alleviated by sediments, which promoted the growth of bacteria and decreased the selective pressure of antibiotics as the vector of bacteria and antibiotics, thus increasing the abundances of denitrifying bacteria and all the DNGs. Partial least-squares path model disclosed that antibiotics had negative effects on bacteria, ARGs and DNGs, while sediments had negative effects on ARGs but positive effects on bacteria and DNGs. The network analysis further revealed the close relation of the genera Bacillus, Acinetobacter, and Enterobacter with the ARGs and DNGs. The findings are helpful to understand the denitrification in antibiotic-polluted natural waters.
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Affiliation(s)
- Ruijie Zhang
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, China; State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, International Joint Laboratory for Regional Pollution Control, Ministry of Education, Beijing 100871, China
| | - Xuming Xu
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, China; State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, International Joint Laboratory for Regional Pollution Control, Ministry of Education, Beijing 100871, China
| | - Dantong Jia
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, China; State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, International Joint Laboratory for Regional Pollution Control, Ministry of Education, Beijing 100871, China
| | - Yitao Lyu
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, China; State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, International Joint Laboratory for Regional Pollution Control, Ministry of Education, Beijing 100871, China
| | - Jingrun Hu
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, China; State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, International Joint Laboratory for Regional Pollution Control, Ministry of Education, Beijing 100871, China
| | - Qian Chen
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, China; State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, International Joint Laboratory for Regional Pollution Control, Ministry of Education, Beijing 100871, China
| | - Weiling Sun
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, China; State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, International Joint Laboratory for Regional Pollution Control, Ministry of Education, Beijing 100871, China.
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18
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Beman JM, Vargas SM, Wilson JM, Perez-Coronel E, Karolewski JS, Vazquez S, Yu A, Cairo AE, White ME, Koester I, Aluwihare LI, Wankel SD. Substantial oxygen consumption by aerobic nitrite oxidation in oceanic oxygen minimum zones. Nat Commun 2021; 12:7043. [PMID: 34857761 PMCID: PMC8639706 DOI: 10.1038/s41467-021-27381-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 11/15/2021] [Indexed: 01/04/2023] Open
Abstract
Oceanic oxygen minimum zones (OMZs) are globally significant sites of biogeochemical cycling where microorganisms deplete dissolved oxygen (DO) to concentrations <20 µM. Amid intense competition for DO in these metabolically challenging environments, aerobic nitrite oxidation may consume significant amounts of DO and help maintain low DO concentrations, but this remains unquantified. Using parallel measurements of oxygen consumption rates and 15N-nitrite oxidation rates applied to both water column profiles and oxygen manipulation experiments, we show that the contribution of nitrite oxidation to overall DO consumption systematically increases as DO declines below 2 µM. Nitrite oxidation can account for all DO consumption only under DO concentrations <393 nM found in and below the secondary chlorophyll maximum. These patterns are consistent across sampling stations and experiments, reflecting coupling between nitrate reduction and nitrite-oxidizing Nitrospina with high oxygen affinity (based on isotopic and omic data). Collectively our results demonstrate that nitrite oxidation plays a pivotal role in the maintenance and biogeochemical dynamics of OMZs.
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Affiliation(s)
- J. M. Beman
- grid.266096.d0000 0001 0049 1282Life and Environmental Sciences, University of California, Merced, Merced, CA USA
| | - S. M. Vargas
- grid.266096.d0000 0001 0049 1282Life and Environmental Sciences, University of California, Merced, Merced, CA USA
| | - J. M. Wilson
- grid.266096.d0000 0001 0049 1282Life and Environmental Sciences, University of California, Merced, Merced, CA USA ,grid.266100.30000 0001 2107 4242Scripps Institution of Oceanography, University of California, San Diego, CA USA
| | - E. Perez-Coronel
- grid.266096.d0000 0001 0049 1282Life and Environmental Sciences, University of California, Merced, Merced, CA USA
| | - J. S. Karolewski
- grid.56466.370000 0004 0504 7510Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA USA
| | - S. Vazquez
- grid.266096.d0000 0001 0049 1282Life and Environmental Sciences, University of California, Merced, Merced, CA USA
| | - A. Yu
- grid.266096.d0000 0001 0049 1282Life and Environmental Sciences, University of California, Merced, Merced, CA USA
| | - A. E. Cairo
- grid.266096.d0000 0001 0049 1282Life and Environmental Sciences, University of California, Merced, Merced, CA USA
| | - M. E. White
- grid.266100.30000 0001 2107 4242Scripps Institution of Oceanography, University of California, San Diego, CA USA
| | - I. Koester
- grid.266100.30000 0001 2107 4242Scripps Institution of Oceanography, University of California, San Diego, CA USA
| | - L. I. Aluwihare
- grid.266100.30000 0001 2107 4242Scripps Institution of Oceanography, University of California, San Diego, CA USA
| | - S. D. Wankel
- grid.56466.370000 0004 0504 7510Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA USA
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19
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Long AM, Jurgensen SK, Petchel AR, Savoie ER, Brum JR. Microbial Ecology of Oxygen Minimum Zones Amidst Ocean Deoxygenation. Front Microbiol 2021; 12:748961. [PMID: 34777296 PMCID: PMC8578717 DOI: 10.3389/fmicb.2021.748961] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 10/06/2021] [Indexed: 01/05/2023] Open
Abstract
Oxygen minimum zones (OMZs) have substantial effects on the global ecology and biogeochemical processes of marine microbes. However, the diversity and activity of OMZ microbes and their trophic interactions are only starting to be documented, especially in regard to the potential roles of viruses and protists. OMZs have expanded over the past 60 years and are predicted to expand due to anthropogenic climate change, furthering the need to understand these regions. This review summarizes the current knowledge of OMZ formation, the biotic and abiotic factors involved in OMZ expansion, and the microbial ecology of OMZs, emphasizing the importance of bacteria, archaea, viruses, and protists. We describe the recognized roles of OMZ microbes in carbon, nitrogen, and sulfur cycling, the potential of viruses in altering host metabolisms involved in these cycles, and the control of microbial populations by grazers and viruses. Further, we highlight the microbial community composition and roles of these organisms in oxic and anoxic depths within the water column and how these differences potentially inform how microbial communities will respond to deoxygenation. Additionally, the current literature on the alteration of microbial communities by other key climate change parameters such as temperature and pH are considered regarding how OMZ microbes might respond to these pressures. Finally, we discuss what knowledge gaps are present in understanding OMZ microbial communities and propose directions that will begin to close these gaps.
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Affiliation(s)
- Andrew M. Long
- Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, LA, United States
| | | | | | | | - Jennifer R. Brum
- Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, LA, United States
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20
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Pascault N, Rué O, Loux V, Pédron J, Martin V, Tambosco J, Bernard C, Humbert JF, Leloup J. Insights into the cyanosphere: capturing the respective metabolisms of cyanobacteria and chemotrophic bacteria in natural conditions? ENVIRONMENTAL MICROBIOLOGY REPORTS 2021; 13:364-374. [PMID: 33763994 DOI: 10.1111/1758-2229.12944] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 03/07/2021] [Indexed: 06/12/2023]
Abstract
Specific interactions have been highlighted between cyanobacteria and chemotrophic bacteria within the cyanosphere, suggesting that nutrients recycling could be optimized by cyanobacteria/bacteria exchanges. In order to determine the respective metabolic roles of the cyanobacterial and bacterial consortia (microbiome), a day-night metatranscriptomic analysis was performed on Dolichospermum sp. (N2 -fixer) and Microcystis sp. (non N2 -fixer) natural blooms occurring successively within a French peri-urban lake. The taxonomical and functional analysis of the metatranscriptoms have highlighted specific association of bacteria within the cyanosphere, driven by the cyanobacteria identity, without strongly modifying the functional composition of the microbiomes, suggesting functional redundancy within the cyanosphere. Moreover, the functional composition of these active communities was driven by the living mode. During the two successive bloom events, it appeared that NH4 + (newly fixed and/or allochthonous) was preferentially transformed into amino acids for the both the microbiome and the cyanobacteria, while phosphate metabolism was enhanced, suggesting that due to a high cellular growth, P limitation might take place within the cyanosphere consortium.
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Affiliation(s)
- Noémie Pascault
- UMR 7618 iEES-Paris Sorbonne Université 4 place Jussieu - 75252 Paris Cedex 05, France
| | - Olivier Rué
- Université Paris-Saclay, INRAE, BioinfOmics, MIGALE Bioinformatics Facility, Jouy-en-Josas, 78350, France
| | - Valentin Loux
- Université Paris-Saclay, INRAE, BioinfOmics, MIGALE Bioinformatics Facility, Jouy-en-Josas, 78350, France
| | - Jacques Pédron
- UMR 7618 iEES-Paris Sorbonne Université 4 place Jussieu - 75252 Paris Cedex 05, France
| | - Véronique Martin
- Université Paris-Saclay, INRAE, BioinfOmics, MIGALE Bioinformatics Facility, Jouy-en-Josas, 78350, France
| | - Jennifer Tambosco
- UMR 7618 iEES-Paris Sorbonne Université 4 place Jussieu - 75252 Paris Cedex 05, France
| | - Cécile Bernard
- UMR 7245 MCAM Muséum National d'Histoire Naturelle - CNRS, 75231 Paris Cedex 05, France
| | - Jean-François Humbert
- UMR 7618 iEES-Paris Sorbonne Université 4 place Jussieu - 75252 Paris Cedex 05, France
| | - Julie Leloup
- UMR 7618 iEES-Paris Sorbonne Université 4 place Jussieu - 75252 Paris Cedex 05, France
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21
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Small sinking particles control anammox rates in the Peruvian oxygen minimum zone. Nat Commun 2021; 12:3235. [PMID: 34050175 PMCID: PMC8163745 DOI: 10.1038/s41467-021-23340-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 04/26/2021] [Indexed: 11/15/2022] Open
Abstract
Anaerobic oxidation of ammonium (anammox) in oxygen minimum zones (OMZs) is a major pathway of oceanic nitrogen loss. Ammonium released from sinking particles has been suggested to fuel this process. During cruises to the Peruvian OMZ in April–June 2017 we found that anammox rates are strongly correlated with the volume of small particles (128–512 µm), even though anammox bacteria were not directly associated with particles. This suggests that the relationship between anammox rates and particles is related to the ammonium released from particles by remineralization. To investigate this, ammonium release from particles was modelled and theoretical encounters of free-living anammox bacteria with ammonium in the particle boundary layer were calculated. These results indicated that small sinking particles could be responsible for ~75% of ammonium release in anoxic waters and that free-living anammox bacteria frequently encounter ammonium in the vicinity of smaller particles. This indicates a so far underestimated role of abundant, slow-sinking small particles in controlling oceanic nutrient budgets, and furthermore implies that observations of the volume of small particles could be used to estimate N-loss across large areas. Up to 40% of the ocean’s fixed nitrogen is lost in oxygen minimum zones (OMZs) by anammox, but despite the importance of this process, nitrogen loss patterns in OMZs are difficult to predict. Here the authors show that ammonium release from small particles is a major control of anammox in the Peruvian OMZ.
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22
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Acinas SG, Sánchez P, Salazar G, Cornejo-Castillo FM, Sebastián M, Logares R, Royo-Llonch M, Paoli L, Sunagawa S, Hingamp P, Ogata H, Lima-Mendez G, Roux S, González JM, Arrieta JM, Alam IS, Kamau A, Bowler C, Raes J, Pesant S, Bork P, Agustí S, Gojobori T, Vaqué D, Sullivan MB, Pedrós-Alió C, Massana R, Duarte CM, Gasol JM. Deep ocean metagenomes provide insight into the metabolic architecture of bathypelagic microbial communities. Commun Biol 2021; 4:604. [PMID: 34021239 PMCID: PMC8139981 DOI: 10.1038/s42003-021-02112-2] [Citation(s) in RCA: 82] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 04/16/2021] [Indexed: 02/04/2023] Open
Abstract
The deep sea, the largest ocean's compartment, drives planetary-scale biogeochemical cycling. Yet, the functional exploration of its microbial communities lags far behind other environments. Here we analyze 58 metagenomes from tropical and subtropical deep oceans to generate the Malaspina Gene Database. Free-living or particle-attached lifestyles drive functional differences in bathypelagic prokaryotic communities, regardless of their biogeography. Ammonia and CO oxidation pathways are enriched in the free-living microbial communities and dissimilatory nitrate reduction to ammonium and H2 oxidation pathways in the particle-attached, while the Calvin Benson-Bassham cycle is the most prevalent inorganic carbon fixation pathway in both size fractions. Reconstruction of the Malaspina Deep Metagenome-Assembled Genomes reveals unique non-cyanobacterial diazotrophic bacteria and chemolithoautotrophic prokaryotes. The widespread potential to grow both autotrophically and heterotrophically suggests that mixotrophy is an ecologically relevant trait in the deep ocean. These results expand our understanding of the functional microbial structure and metabolic capabilities of the largest Earth aquatic ecosystem.
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Affiliation(s)
- Silvia G Acinas
- Department of Marine Biology and Oceanography, Institute of Marine Sciences (ICM), CSIC, Barcelona, Spain.
| | - Pablo Sánchez
- Department of Marine Biology and Oceanography, Institute of Marine Sciences (ICM), CSIC, Barcelona, Spain
| | - Guillem Salazar
- Department of Marine Biology and Oceanography, Institute of Marine Sciences (ICM), CSIC, Barcelona, Spain
- Department of Biology, Institute of Microbiology and Swiss Institute of Bioinformatics, ETH Zurich, Zurich, Switzerland
| | - Francisco M Cornejo-Castillo
- Department of Marine Biology and Oceanography, Institute of Marine Sciences (ICM), CSIC, Barcelona, Spain
- Department of Ocean Sciences, University of California, Santa Cruz, CA, USA
| | - Marta Sebastián
- Department of Marine Biology and Oceanography, Institute of Marine Sciences (ICM), CSIC, Barcelona, Spain
- Instituto de Oceanografía y Cambio Global, IOCAG, Universidad de Las Palmas de Gran Canaria, ULPGC, Gran Canaria, Spain
| | - Ramiro Logares
- Department of Marine Biology and Oceanography, Institute of Marine Sciences (ICM), CSIC, Barcelona, Spain
| | - Marta Royo-Llonch
- Department of Marine Biology and Oceanography, Institute of Marine Sciences (ICM), CSIC, Barcelona, Spain
| | - Lucas Paoli
- Department of Biology, Institute of Microbiology and Swiss Institute of Bioinformatics, ETH Zurich, Zurich, Switzerland
| | - Shinichi Sunagawa
- Department of Biology, Institute of Microbiology and Swiss Institute of Bioinformatics, ETH Zurich, Zurich, Switzerland
| | - Pascal Hingamp
- Aix Marseille Univ., Université de Toulon, CNRS, Marseille, France
| | - Hiroyuki Ogata
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Japan
| | - Gipsi Lima-Mendez
- Cellular and Molecular Microbiology, Faculté des Sciences, Université libre de Bruxelles (ULB), Brussels, Belgium
- Interuniversity Institute for Bioinformatics in Brussels, ULB-VUB, Brussels, Belgium
| | - Simon Roux
- Department of Microbiology, The Ohio State University, Columbus, OH, USA
- U.S. Department of Energy Joint Genome Institute, Berkeley, CA, USA
| | - José M González
- Department of Microbiology, University of La Laguna, La Laguna, Spain
| | - Jesús M Arrieta
- Spanish Institute of Oceanography (IEO), Oceanographic Center of The Canary Islands, Dársena Pesquera, Santa Cruz de Tenerife, Spain
| | - Intikhab S Alam
- King Abdullah University of Science and Technology (KAUST), Computational Bioscience Research Center (CBRC), Thuwal, Saudi Arabia
| | - Allan Kamau
- King Abdullah University of Science and Technology (KAUST), Computational Bioscience Research Center (CBRC), Thuwal, Saudi Arabia
| | - Chris Bowler
- Institut de Biologie de l'ENS (IBENS), Département de biologie, École normale supérieure, CNRS, INSERM, Université PSL, Paris, France
- Research Federation for the study of Global Ocean Systems Ecology and Evolution, Paris, France
| | - Jeroen Raes
- Department of Microbiology and Immunology, Rega Institute, KU Leuven - University of Leuven, Leuven, Belgium
- VIB Center for Microbiology, Leuven, Belgium
| | - Stéphane Pesant
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Hinxton, Cambridge, United Kingdom
- PANGAEA, Data Publisher for Earth and Environmental Science, University of Bremen, Bremen, Germany
| | - Peer Bork
- Structural and Computational Biology, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Susana Agustí
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center (RSRC), Thuwal, Saudi Arabia
| | - Takashi Gojobori
- King Abdullah University of Science and Technology (KAUST), Computational Bioscience Research Center (CBRC), Thuwal, Saudi Arabia
| | - Dolors Vaqué
- Department of Marine Biology and Oceanography, Institute of Marine Sciences (ICM), CSIC, Barcelona, Spain
| | - Matthew B Sullivan
- Department of Microbiology and Civil Environmental and Geodetic Engineering, The Ohio State University, Columbus, OH, USA
| | - Carlos Pedrós-Alió
- Department of Systems Biology, Centro Nacional de Biotecnología (CNB), CSIC, Madrid, Spain
| | - Ramon Massana
- Department of Marine Biology and Oceanography, Institute of Marine Sciences (ICM), CSIC, Barcelona, Spain
| | - Carlos M Duarte
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center (RSRC) and Computational Bioscience Research Center (CBRC), Thuwal, Saudi Arabia
| | - Josep M Gasol
- Department of Marine Biology and Oceanography, Institute of Marine Sciences (ICM), CSIC, Barcelona, Spain
- Centre for Marine Ecosystems Research, School of Sciences, Edith Cowan University, Joondalup, WA, Australia
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23
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Denitrifying bacteria respond to and shape microscale gradients within particulate matrices. Commun Biol 2021; 4:570. [PMID: 33986448 PMCID: PMC8119678 DOI: 10.1038/s42003-021-02102-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 04/13/2021] [Indexed: 11/10/2022] Open
Abstract
Heterotrophic denitrification enables facultative anaerobes to continue growing even when limited by oxygen (O2) availability. Particles in particular provide physical matrices characterized by reduced O2 permeability even in well-oxygenated bulk conditions, creating microenvironments where microbial denitrifiers may proliferate. Whereas numerical particle models generally describe denitrification as a function of radius, here we provide evidence for heterogeneity of intraparticle denitrification activity due to local interactions within and among microcolonies. Pseudomonas aeruginosa cells and microcolonies act to metabolically shade each other, fostering anaerobic processes just microns from O2-saturated bulk water. Even within well-oxygenated fluid, suboxia and denitrification reproducibly developed and migrated along sharp 10 to 100 µm gradients, driven by the balance of oxidant diffusion and local respiration. Moreover, metabolic differentiation among densely packed cells is dictated by the diffusional supply of O2, leading to distinct bimodality in the distribution of nitrate and nitrite reductase expression. The initial seeding density controls the speed at which anoxia develops, and even particles seeded with few bacteria remain capable of becoming anoxic. Our empirical results capture the dynamics of denitrifier gene expression in direct association with O2 concentrations over microscale physical matrices, providing observations of the co-occurrence and spatial arrangement of aerobic and anaerobic processes. Smriga et al. investigate heterotrophic denitrification in particulate matrices. Their model shows that Pseudomonas aeruginosa cells and microcolonies metabolically shade each other, allowing denitrification to occur microns away from O2-saturated bulk water, and simulates microscale effects of a bulk system.
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24
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Microbial niche differentiation explains nitrite oxidation in marine oxygen minimum zones. THE ISME JOURNAL 2021; 15:1317-1329. [PMID: 33408366 PMCID: PMC8114937 DOI: 10.1038/s41396-020-00852-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 11/13/2020] [Accepted: 11/20/2020] [Indexed: 01/29/2023]
Abstract
Nitrite is a pivotal component of the marine nitrogen cycle. The fate of nitrite determines the loss or retention of fixed nitrogen, an essential nutrient for all organisms. Loss occurs via anaerobic nitrite reduction to gases during denitrification and anammox, while retention occurs via nitrite oxidation to nitrate. Nitrite oxidation is usually represented in biogeochemical models by one kinetic parameter and one oxygen threshold, below which nitrite oxidation is set to zero. Here we find that the responses of nitrite oxidation to nitrite and oxygen concentrations vary along a redox gradient in a Pacific Ocean oxygen minimum zone, indicating niche differentiation of nitrite-oxidizing assemblages. Notably, we observe the full inhibition of nitrite oxidation by oxygen addition and nitrite oxidation coupled with nitrogen loss in the absence of oxygen consumption in samples collected from anoxic waters. Nitrite-oxidizing bacteria, including novel clades with high relative abundance in anoxic depths, were also detected in the same samples. Mechanisms corresponding to niche differentiation of nitrite-oxidizing bacteria across the redox gradient are considered. Implementing these mechanisms in biogeochemical models has a significant effect on the estimated fixed nitrogen budget.
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25
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Gazitúa MC, Vik DR, Roux S, Gregory AC, Bolduc B, Widner B, Mulholland MR, Hallam SJ, Ulloa O, Sullivan MB. Potential virus-mediated nitrogen cycling in oxygen-depleted oceanic waters. THE ISME JOURNAL 2021; 15:981-998. [PMID: 33199808 PMCID: PMC8115048 DOI: 10.1038/s41396-020-00825-6] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 09/30/2020] [Accepted: 10/27/2020] [Indexed: 01/29/2023]
Abstract
Viruses play an important role in the ecology and biogeochemistry of marine ecosystems. Beyond mortality and gene transfer, viruses can reprogram microbial metabolism during infection by expressing auxiliary metabolic genes (AMGs) involved in photosynthesis, central carbon metabolism, and nutrient cycling. While previous studies have focused on AMG diversity in the sunlit and dark ocean, less is known about the role of viruses in shaping metabolic networks along redox gradients associated with marine oxygen minimum zones (OMZs). Here, we analyzed relatively quantitative viral metagenomic datasets that profiled the oxygen gradient across Eastern Tropical South Pacific (ETSP) OMZ waters, assessing whether OMZ viruses might impact nitrogen (N) cycling via AMGs. Identified viral genomes encoded six N-cycle AMGs associated with denitrification, nitrification, assimilatory nitrate reduction, and nitrite transport. The majority of these AMGs (80%) were identified in T4-like Myoviridae phages, predicted to infect Cyanobacteria and Proteobacteria, or in unclassified archaeal viruses predicted to infect Thaumarchaeota. Four AMGs were exclusive to anoxic waters and had distributions that paralleled homologous microbial genes. Together, these findings suggest viruses modulate N-cycling processes within the ETSP OMZ and may contribute to nitrogen loss throughout the global oceans thus providing a baseline for their inclusion in the ecosystem and geochemical models.
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Affiliation(s)
- M. Consuelo Gazitúa
- grid.261331.40000 0001 2285 7943Department of Microbiology, The Ohio State University, Columbus, OH 43210 USA ,Viromica Consulting, Santiago, Chile
| | - Dean R. Vik
- grid.261331.40000 0001 2285 7943Department of Microbiology, The Ohio State University, Columbus, OH 43210 USA
| | - Simon Roux
- grid.451309.a0000 0004 0449 479XDOE Joint Genome Institute, Berkeley, CA USA
| | - Ann C. Gregory
- grid.261331.40000 0001 2285 7943Department of Microbiology, The Ohio State University, Columbus, OH 43210 USA
| | - Benjamin Bolduc
- grid.261331.40000 0001 2285 7943Department of Microbiology, The Ohio State University, Columbus, OH 43210 USA
| | - Brittany Widner
- grid.261368.80000 0001 2164 3177Department of Ocean, Earth and Atmospheric Sciences, Old Dominion University, Norfolk, VA USA ,grid.56466.370000 0004 0504 7510Woods Hole Oceanographic Institution, Woods Hole, MA USA
| | - Margaret R. Mulholland
- grid.261368.80000 0001 2164 3177Department of Ocean, Earth and Atmospheric Sciences, Old Dominion University, Norfolk, VA USA
| | - Steven J. Hallam
- grid.17091.3e0000 0001 2288 9830Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC Canada
| | - Osvaldo Ulloa
- grid.5380.e0000 0001 2298 9663Departamento de Oceanografía & Instituto Milenio de Oceanografía, Universidad de Concepción, Concepción, Chile
| | - Matthew B. Sullivan
- grid.261331.40000 0001 2285 7943Department of Microbiology, The Ohio State University, Columbus, OH 43210 USA ,grid.261331.40000 0001 2285 7943Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, Columbus, OH USA
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26
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A simple and sensitive direct mRNA multiplexed detection strategy for amoA-targeted monitoring of ammonia-oxidizing activity in water environment. Microchem J 2021. [DOI: 10.1016/j.microc.2020.105794] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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27
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Ruiz-Perez CA, Bertagnolli AD, Tsementzi D, Woyke T, Stewart FJ, Konstantinidis KT. Description of Candidatus Mesopelagibacter carboxydoxydans and Candidatus Anoxipelagibacter denitrificans: Nitrate-reducing SAR11 genera that dominate mesopelagic and anoxic marine zones. Syst Appl Microbiol 2021; 44:126185. [PMID: 33676264 DOI: 10.1016/j.syapm.2021.126185] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 11/25/2020] [Accepted: 12/09/2020] [Indexed: 11/29/2022]
Abstract
The diverse and ubiquitous members of the SAR11 lineage (Alphaproteobacteria) represent up to 30-40% of the surface and mesopelagic oceanic microbial communities. However, the molecular and ecological mechanisms that differentiate closely related, yet distinct, SAR11 members that often co-occur under similar environmental conditions remain speculative. Recently, two mesopelagic and oxygen minimum zone (OMZ)-associated subclades of SAR11 (Ic and IIa.A) were described using single-cell amplified genomes (SAGs) linked to nitrate reduction in OMZs. In this current study, the collection of genomes belonging to these two subclades was expanded with thirteen new metagenome-assembled genomes (MAGs), thus providing a more detailed phylogenetic and functional characterization of these subclades. Gene content-based predictions of metabolic functions revealed similarities in central carbon metabolism between subclades Ic and IIa.A and surface SAR11 clades, with small variations in central pathways. These variations included more versatile sulfur assimilation pathways, as well as a previously predicted capacity for nitrate reduction that conferred unique versatility on mesopelagic-adapted clades compared to their surface counterparts. Finally, consistent with previously reported abundances of carbon monoxide (CO) in surface and mesopelagic waters, subclades Ia (surface) and Ic (mesopelagic) have the genetic potential to oxidize carbon monoxide (CO), presumably taking advantage of this abundant compound as an electron donor. Based on genomic analyses, environmental distribution and metabolic reconstruction, we propose two new SAR11 genera, Ca. Mesopelagibacter carboxydoxydans (subclade Ic) and Ca. Anoxipelagibacter denitrificans (subclade IIa.A), which represent members of the mesopelagic and OMZ-adapted SAR11 clades.
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Affiliation(s)
- Carlos A Ruiz-Perez
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Anthony D Bertagnolli
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Despina Tsementzi
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Tanja Woyke
- DOE Joint Genome Institute, One Cyclotron Road, Mail Stop 91R0183, Berkeley, CA 94720, USA
| | - Frank J Stewart
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA; Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, GA 30332, USA; Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA
| | - Konstantinos T Konstantinidis
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA; School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA; Center for Bioinformatics and Computational Genomics, Georgia Institute of Technology, Atlanta, GA 30332, USA.
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28
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Phoma BS, Makhalanyane TP. Depth-Dependent Variables Shape Community Structure and Functionality in the Prince Edward Islands. MICROBIAL ECOLOGY 2021; 81:396-409. [PMID: 32935183 DOI: 10.1007/s00248-020-01589-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 08/03/2020] [Indexed: 06/11/2023]
Abstract
Physicochemical variables limit and control the distribution of microbial communities in all environments. In the oceans, this may significantly influence functional processes such the consumption of dissolved organic material and nutrient sequestration. Yet, the relative contributions of physical factors, such as water mass variability and depth, on functional processes are underexplored. We assessed microbial community structure and functionality in the Prince Edward Islands (PEIs) using 16S rRNA gene amplicon analysis and extracellular enzymatic activity assays, respectively. We found that depth and nutrients substantially drive the structural patterns of bacteria and archaea in this region. Shifts from epipelagic to bathypelagic zones were linked to decreases in the activities of several extracellular enzymes. These extracellular enzymatic activities were positively correlated with several phyla including several Alphaproteobacteria (including members of the SAR 11 clade and order Rhodospirillales) and Cyanobacteria. We show that depth-dependent variables may be essential drivers of community structure and functionality in the PEIs.
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Affiliation(s)
- Boitumelo Sandra Phoma
- Centre for Microbial Ecology and Genomics (CMEG), Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Hatfield, Pretoria, 0028, South Africa
- Marine Microbiomics Programme, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, 0028, South Africa
| | - Thulani Peter Makhalanyane
- Centre for Microbial Ecology and Genomics (CMEG), Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Hatfield, Pretoria, 0028, South Africa.
- Marine Microbiomics Programme, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, 0028, South Africa.
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29
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Sun X, Jayakumar A, Tracey JC, Wallace E, Kelly CL, Casciotti KL, Ward BB. Microbial N 2O consumption in and above marine N 2O production hotspots. ISME JOURNAL 2020; 15:1434-1444. [PMID: 33349653 PMCID: PMC8115077 DOI: 10.1038/s41396-020-00861-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 11/20/2020] [Accepted: 11/26/2020] [Indexed: 11/10/2022]
Abstract
The ocean is a net source of N2O, a potent greenhouse gas and ozone-depleting agent. However, the removal of N2O via microbial N2O consumption is poorly constrained and rate measurements have been restricted to anoxic waters. Here we expand N2O consumption measurements from anoxic zones to the sharp oxygen gradient above them, and experimentally determine kinetic parameters in both oxic and anoxic seawater for the first time. We find that the substrate affinity, O2 tolerance, and community composition of N2O-consuming microbes in oxic waters differ from those in the underlying anoxic layers. Kinetic parameters determined here are used to model in situ N2O production and consumption rates. Estimated in situ rates differ from measured rates, confirming the necessity to consider kinetics when predicting N2O cycling. Microbes from the oxic layer consume N2O under anoxic conditions at a much faster rate than microbes from anoxic zones. These experimental results are in keeping with model results which indicate that N2O consumption likely takes place above the oxygen deficient zone (ODZ). Thus, the dynamic layer with steep O2 and N2O gradients right above the ODZ is a previously ignored potential gatekeeper of N2O and should be accounted for in the marine N2O budget.
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Affiliation(s)
- Xin Sun
- Department of Geosciences, Princeton University, Princeton, NJ, 08544, USA.
| | - Amal Jayakumar
- Department of Geosciences, Princeton University, Princeton, NJ, 08544, USA
| | - John C Tracey
- Department of Geosciences, Princeton University, Princeton, NJ, 08544, USA
| | - Elizabeth Wallace
- Department of Geosciences, Princeton University, Princeton, NJ, 08544, USA
| | - Colette L Kelly
- Department of Earth System Science, Stanford University, Stanford, CA, 94305, USA
| | - Karen L Casciotti
- Department of Earth System Science, Stanford University, Stanford, CA, 94305, USA
| | - Bess B Ward
- Department of Geosciences, Princeton University, Princeton, NJ, 08544, USA
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30
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Bertagnolli AD, Konstantinidis KT, Stewart FJ. Non-denitrifier nitrous oxide reductases dominate marine biomes. ENVIRONMENTAL MICROBIOLOGY REPORTS 2020; 12:681-692. [PMID: 33459515 DOI: 10.1111/1758-2229.12879] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 08/12/2020] [Accepted: 08/14/2020] [Indexed: 06/12/2023]
Abstract
Microbial enzymes often occur as distinct variants that share the same substrate but differ in substrate affinity, sensitivity to environmental conditions, or phylogenetic ancestry. Determining where variants occur in the environment helps identify thresholds that constrain microbial cycling of key chemicals, including the greenhouse gas nitrous oxide (N2O). To understand the enzymatic basis of N2O cycling in the ocean, we mined metagenomes to characterize genes encoding bacterial nitrous oxide reductase (NosZ) catalyzing N2O reduction to N2. We examined data sets from diverse biomes but focused primarily on those from oxygen minimum zones where N2O levels are often elevated. With few exceptions, marine nosZ data sets were dominated by 'atypical' clade II gene variants. Atypical nosZ has been associated with low oxygen, enhanced N2O affinity, and organisms lacking enzymes for complete denitrification, i.e., non-denitrifiers. Atypical nosZ often occurred in metagenome-assembled genomes (MAGs) with nitrate or nitrite respiration genes, although MAGs with genes for complete denitrification were rare. We identified atypical nosZ in several taxa not previously associated with N2O consumption, in addition to known N2O-associated groups. The data suggest that marine environments generally select for high N2O-scavenging ability across diverse taxa and have implications for how N2O concentration may affect N2O removal rates.
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Affiliation(s)
- Anthony D Bertagnolli
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, 59717, USA
- School of Biological Sciences, Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | | | - Frank J Stewart
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, 59717, USA
- School of Biological Sciences, Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, GA, 30332, USA
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31
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Pajares S, Varona-Cordero F, Hernández-Becerril DU. Spatial Distribution Patterns of Bacterioplankton in the Oxygen Minimum Zone of the Tropical Mexican Pacific. MICROBIAL ECOLOGY 2020; 80:519-536. [PMID: 32415330 DOI: 10.1007/s00248-020-01508-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 03/23/2020] [Indexed: 05/16/2023]
Abstract
Microbial communities within oxygen minimum zones (OMZs) are crucial drivers of marine biogeochemical cycles; however, we still lack an understanding of how these communities are distributed across an OMZ. We explored vertical (from 5 to 500 m depth) and horizontal (coast to open ocean) distribution of bacterioplankton and its relationships with the main oceanographic conditions in three transects of the tropical Mexican Pacific OMZ. The distribution of the microbial diversity and the main clades changed along the transition from oxygen-rich surface water to the OMZ core, demonstrating the sensitivity of key bacterial groups to deoxygenation. The euphotic zone was dominated by Synechococcales, followed by Flavobacteriales, Verrucomicrobiales, Rhodobacterales, SAR86, and Cellvibrionales, whereas the OMZ core was dominated by SAR11, followed by SAR406, SAR324, SAR202, UBA10353 marine group, Thiomicrospirales and Nitrospinales. The marked environmental gradients along the water column also supported a high potential for niche partitioning among OMZ microorganisms. Additionally, in the OMZ core, bacterial assemblages from the same water mass were more similar to each other than those from another water mass. There were also important differences between coastal and open-ocean communities: Flavobacteriales, Verrucomicrobiales, Rhodobacterales, SAR86, and Cellvibrionales were more abundant in coastal areas, while Synechococcales, SAR406, SAR324, SAR202, UBA10353 marine group, and Thiomicrospirales were more abundant in the open ocean. Our results suggest a biogeographic structure of the bacterioplankton in this OMZ region, with limited community mixing across water masses, except in upwelling events, and little dispersion of the community by currents in the euphotic zone.
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Affiliation(s)
- Silvia Pajares
- Unidad Académica de Ecología y Biodiversidad Acuática, Institute of Marine Sciences and Limnology, National Autonomous University of Mexico, Mexico City, Mexico.
| | - Francisco Varona-Cordero
- Unidad Académica de Ecología y Biodiversidad Acuática, Institute of Marine Sciences and Limnology, National Autonomous University of Mexico, Mexico City, Mexico
| | - David Uriel Hernández-Becerril
- Unidad Académica de Ecología y Biodiversidad Acuática, Institute of Marine Sciences and Limnology, National Autonomous University of Mexico, Mexico City, Mexico
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32
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Fuchsman CA, Stüeken EE. Using modern low-oxygen marine ecosystems to understand the nitrogen cycle of the Paleo- and Mesoproterozoic oceans. Environ Microbiol 2020; 23:2801-2822. [PMID: 32869502 DOI: 10.1111/1462-2920.15220] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 08/25/2020] [Accepted: 08/27/2020] [Indexed: 11/29/2022]
Abstract
During the productive Paleoproterozoic (2.4-1.8 Ga) and less productive Mesoproterozoic (1.8-1.0 Ga), the ocean was suboxic to anoxic and multicellular organisms had not yet evolved. Here, we link geologic information about the Proterozoic ocean to microbial processes in modern low-oxygen systems. High iron concentrations and rates of Fe cycling in the Proterozoic are the largest differences from modern oxygen-deficient zones. In anoxic waters, which composed most of the Paleoproterozoic and ~40% of the Mesoproterozoic ocean, nitrogen cycling dominated. Rates of N2 production by denitrification and anammox were likely linked to sinking organic matter fluxes and in situ primary productivity under anoxic conditions. Additionally autotrophic denitrifiers could have used reduced iron or methane. 50% of the Mesoproterozoic ocean may have been suboxic, promoting nitrification and metal oxidation in the suboxic water and N2 O and N2 production by partial and complete denitrification in anoxic zones in organic aggregates. Sulfidic conditions may have composed ~10% of the Mesoproterozoic ocean focused along continental margins. Due to low nitrate concentrations in offshore regions, anammox bacteria likely dominated N2 production immediately above sulfidic zones, but in coastal regions, higher nitrate concentrations probably promoted complete S-oxidizing autotrophic denitrification at the sulfide interface.
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Affiliation(s)
- Clara A Fuchsman
- Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, MD, 21613, USA
| | - Eva E Stüeken
- School of Earth & Environmental Sciences, University of St Andrews, St Andrews, KY16 9AL, Scotland, UK
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Seasonality and Community Separation of Fungi in a Municipal Wastewater Treatment Plant. Appl Environ Microbiol 2020; 86:AEM.00991-20. [PMID: 32651202 DOI: 10.1128/aem.00991-20] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 06/30/2020] [Indexed: 11/20/2022] Open
Abstract
Fungi are known to play important roles in pollutant transformation in activated sludge-based wastewater treatment plants (WWTPs). However, the seasonality and distributions of fungal populations in different-sized flocs have still remained largely unknown. In this study, seasonal population dynamics and community separation of fungi in a municipal WWTP across a 1-year period were investigated. We classified all taxa into six categories based on abundances to assess their roles and contributions to the whole community. The results showed that the rare taxa (<0.01%) contributed greatly to species richness (95.27%). Conversely, although low in species diversity, abundant taxa (≥1%) accounted for the majority (89.45%) of the total relative abundance, which suggested that a few core abundant fungi existed in the activated sludge ecosystem. The abundant, conditionally rare, and rare taxa contributed 30.14%, 31.11%, and 38.75%, respectively, to temporal shifts in community structure, and their abundances responded differently to environmental variables, suggesting that these three subcommunities exhibited a large difference in environmental sensitivity. Importantly, the results revealed seasonal dynamics of the whole fungal community and the subcommunities of all the microbial taxon categories, resulting in significant differences in community structures between warm and cold seasons. Furthermore, fungal diversity and the compositions of the whole community and subcommunities differed significantly among flocs of different sizes, which underlined the size-based fungal community separation in activated sludge of WWTPs. The findings of this work improved our understanding of fungal population dynamics and community separation in WWTPs.IMPORTANCE Fungi are important contributors to the various functions of activated sludge in wastewater treatment plants (WWTPs). Unlike previous studies, this work demonstrated the seasonality of the fungal community over a longer time span while it also systematically assessed the contributions of abundant, conditionally rare, and rare taxa to the whole community. Importantly, in the present study, we considered sludge flocs of a certain size range rather than the whole sludge flocs as a community. Our results revealed significant differences in fungal community structure among different-sized flocs, which supported the idea that size-based fungal community segregation is occurring in activated sludge ecosystems. The findings provide new insights into the dynamic changes or distribution of fungi in the bioaggregates of sludge flocs in WWTPs.
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Suter EA, Pachiadaki MG, Montes E, Edgcomb VP, Scranton MI, Taylor CD, Taylor GT. Diverse nitrogen cycling pathways across a marine oxygen gradient indicate nitrogen loss coupled to chemoautotrophic activity. Environ Microbiol 2020; 23:2747-2764. [PMID: 32761757 DOI: 10.1111/1462-2920.15187] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Revised: 08/01/2020] [Accepted: 08/02/2020] [Indexed: 11/28/2022]
Abstract
Genetic markers and geochemical assays of microbial nitrogen cycling processes, including autotrophic and heterotrophic denitrification, anammox, ammonia oxidation, and nitrite oxidation, were examined across the oxycline, suboxic, and anoxic zones of the Cariaco Basin, Venezuela. Ammonia and nitrite oxidation genes were expressed through the entire gradient. Transcripts associated with autotrophic and heterotrophic denitrifiers were mostly confined to the suboxic zone and below but were also present in particles in the oxycline. Anammox genes and transcripts were detected over a narrow depth range near the bottom of the suboxic zone and coincided with secondary NO2 - maxima and available NH4 + . Dissolved inorganic nitrogen (DIN) amendment incubations and comparisons between our sampling campaigns suggested that denitrifier activity may be closely coupled with NO3 - availability. Expression of denitrification genes at depths of high rates of chemoautotrophic carbon fixation and phylogenetic analyses of nitrogen cycling genes and transcripts indicated a diverse array of denitrifiers, including chemoautotrophs capable of using NO3 - to oxidize reduced sulfur species. Thus, results suggest that the Cariaco Basin nitrogen cycle is influenced by autotrophic carbon cycling in addition to organic matter oxidation and anammox.
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Affiliation(s)
- Elizabeth A Suter
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, USA.,Biology, Chemistry, and Environmental Studies Department, Center for Environmental Research and Coastal Oceans Monitoring, Molloy College, Rockville Centre, NY, USA.,Department of Biological Sciences, Wagner College, Staten Island, NY, USA
| | - Maria G Pachiadaki
- Woods Hole Oceanographic Institution, Woods Hole, MA, USA.,Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, USA
| | - Enrique Montes
- College of Marine Science, University of South Florida, St. Petersburg, FL, USA
| | | | - Mary I Scranton
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, USA
| | - Craig D Taylor
- Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - Gordon T Taylor
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, USA
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35
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Morin L, Goubet A, Madigou C, Pernelle JJ, Palmier K, Labadie K, Lemainque A, Michot O, Astoul L, Barbier P, Almayrac JL, Sghir A. Colonization kinetics and implantation follow-up of the sewage microbiome in an urban wastewater treatment plant. Sci Rep 2020; 10:11634. [PMID: 32669657 PMCID: PMC7363871 DOI: 10.1038/s41598-020-68496-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 06/24/2020] [Indexed: 12/02/2022] Open
Abstract
The Seine-Morée wastewater treatment plant (SM_WWTP), with a capacity of 100,000 population-equivalents, was fed with raw domestic wastewater during all of its start-up phase. Its microbiome resulted from the spontaneous evolution of wastewater-borne microorganisms. This rare opportunity allowed us to analyze the sequential microbiota colonization and implantation follow up during the start-up phase of this WWTP by means of regular sampling carried out over 8 months until the establishment of a stable and functional ecosystem. During the study, biological nitrification–denitrification and dephosphatation occurred 68 days after the start-up of the WWTP, followed by flocs decantation 91 days later. High throughput sequencing of 18S and 16S rRNA genes was performed using Illumina's MiSeq and PGM Ion Torrent platforms respectively, generating 584,647 16S and 521,031 18S high-quality sequence rDNA reads. Analyses of 16S and 18S rDNA datasets show three colonization phases occurring concomitantly with nitrification, dephosphatation and floc development processes. Thus, we could define three microbiota profiles that sequentially colonized the SM_WWTP: the early colonizers, the late colonizers and the continuous spectrum population. Shannon and inverse Simpson diversity indices indicate that the highest microbiota diversity was reached at days 133 and 82 for prokaryotes and eukaryotes respectively; after that, the structure and complexity of the wastewater microbiome reached its functional stability. This study demonstrates that physicochemical parameters and microbial metabolic interactions are the main forces shaping microbial community structure, gradually building up and maintaining a functionally stable microbial ecosystem.
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Affiliation(s)
- Loïc Morin
- Institut de Biologie Intégrative de la Cellule, Université Paris Saclay, 91405, Orsay Cedex, France
| | - Anne Goubet
- INRAE, PROSE, Université Paris-Saclay, 92761, Antony, France
| | - Céline Madigou
- INRAE, PROSE, Université Paris-Saclay, 92761, Antony, France
| | | | - Karima Palmier
- Institut de Biologie Intégrative de la Cellule, Université Paris Saclay, 91405, Orsay Cedex, France
| | - Karine Labadie
- Genoscope, Institut de Biologie François-Jacob, CEA, Université Paris-Saclay, 91057, Evry, France
| | - Arnaud Lemainque
- Genoscope, Institut de Biologie François-Jacob, CEA, Université Paris-Saclay, 91057, Evry, France
| | - Ophélie Michot
- Laboratoire SIAAP Site Seine Amont, Usine Marne Aval, 100 rue de la Plaine, 93160, Noisy-Le-Grand, France
| | - Lucie Astoul
- Laboratoire SIAAP Site Seine Amont, Usine Marne Aval, 100 rue de la Plaine, 93160, Noisy-Le-Grand, France
| | - Paul Barbier
- Génomique métabolique, Genoscope, Institut de Biologie François Jacob, CEA, CNRS, Université d'Evry, Université Paris-Saclay, 91057, Evry, France
| | - Jean-Luc Almayrac
- Laboratoire SIAAP Site Seine Amont, Usine Marne Aval, 100 rue de la Plaine, 93160, Noisy-Le-Grand, France
| | - Abdelghani Sghir
- Génomique métabolique, Genoscope, Institut de Biologie François Jacob, CEA, CNRS, Université d'Evry, Université Paris-Saclay, 91057, Evry, France.
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Zhang S, Li B, Yu Z, Meng F. Aggregate size-dependence of bacterial community separation in a full-scale membrane bioreactor plant. FEMS Microbiol Ecol 2020; 96:5818762. [PMID: 32275301 DOI: 10.1093/femsec/fiaa060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 04/02/2020] [Indexed: 11/13/2022] Open
Abstract
The size of bacterial aggregates can determine both nutrient removal and sludge/water separation in activated sludge processes. In this study, the bacterial community structures and network associations of different sized aggregates obtained from a full-scale membrane bioreactor plant over a one-year period were investigated. Our results showed that biodiversity of larger sized aggregates was significantly higher than that of smaller ones and that the bacterial compositions of different sized aggregates differed significantly from each other. Bacteria related to nutrient removal (e.g. denitrification, hydrolysis and fermentation) were found to be significantly more abundant in larger aggregates than smaller ones. Network analysis revealed significant difference in species-species interactions, topological roles of individual OTU and keystone populations among different sized aggregates. Moreover, the occurrence of keystone OTUs affiliated with denitrifiers (Thermomonas) in networks of large and medium aggregates may suggest that denitrification influences bacterial interactions in large and medium aggregates. Overall, our results indicate the aggregates size-dependence of bacterial community separation in activated sludge. The current findings not only can provide guidance for process design and operation optimization, but also highlight the necessity for paying more attentions to the aggregate-based community, metabolic function and gene expression of activated sludge in future studies.
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Affiliation(s)
- Shaoqing Zhang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, PR China.,Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology (Sun Yat-sen University), Guangzhou 510275, PR China
| | - Bing Li
- Division of Energy and Environment, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, PR China
| | - Zhong Yu
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, PR China.,Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology (Sun Yat-sen University), Guangzhou 510275, PR China
| | - Fangang Meng
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, PR China.,Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology (Sun Yat-sen University), Guangzhou 510275, PR China
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37
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He P, Xie L, Zhang X, Li J, Lin X, Pu X, Yuan C, Tian Z, Li J. Microbial Diversity and Metabolic Potential in the Stratified Sansha Yongle Blue Hole in the South China Sea. Sci Rep 2020; 10:5949. [PMID: 32249806 PMCID: PMC7136235 DOI: 10.1038/s41598-020-62411-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 03/11/2020] [Indexed: 01/08/2023] Open
Abstract
The Sansha Yongle Blue Hole is the world’s deepest (301 m) underwater cave and has a sharp redox gradient, with oligotrophic, anoxic, and sulfidic bottom seawater. In order to discover the microbial communities and their special biogeochemical pathways in the blue hole, we analyzed the 16S ribosomal RNA amplicons and metagenomes of microbials from seawater depths with prominent physical, chemical, and biological features. Redundancy analysis showed that dissolved oxygen was the most important factor affecting the microbial assemblages of the blue hole and surrounding open sea waters, and significantly explained 44.7% of the total variation, followed by silicate, temperature, sulfide, ammonium, methane, nitrous oxide, nitrate, dissolved organic carbon, salinity, particulate organic carbon, and chlorophyll a. We identified a bloom of Alteromonas (34.9%) at the primary nitrite maximum occurring in close proximity to the chlorophyll a peak in the blue hole. Genomic potential for nitrate reduction of Alteromonas might contribute to this maximum under oxygen decrease. Genes that would allow for aerobic ammonium oxidation, complete denitrification, and sulfur-oxidization were enriched at nitrate/nitrite-sulfide transition zone (90 and 100 m) of the blue hole, but not anammox pathways. Moreover, γ-Proteobacterial clade SUP05, ε-Proteobacterial genera Sulfurimonas and Arcobacter, and Chlorobi harbored genes for sulfur-driven denitrification process that mediated nitrogen loss and sulfide removal. In the anoxic bottom seawater (100-300 m), high levels of sulfate reducers and dissimilatory sulfite reductase gene (dsrA) potentially created a sulfidic zone of ~200 m thickness. Our findings suggest that in the oligotrophic Sansha Yongle Blue Hole, O2 deficiency promotes nitrogen- and sulfur-cycling processes mediated by metabolically versatile microbials.
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Affiliation(s)
- Peiqing He
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China. .,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China. .,Key Laboratory of Natural Products of Qingdao, Qingdao, 266061, China.
| | - Linping Xie
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China
| | - Xuelei Zhang
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China
| | - Jiang Li
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China.,Key Laboratory of Natural Products of Qingdao, Qingdao, 266061, China
| | - Xuezheng Lin
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China.,Key Laboratory of Natural Products of Qingdao, Qingdao, 266061, China
| | - Xinming Pu
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China
| | - Chao Yuan
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China
| | - Ziwen Tian
- Research Center for Islands and Coastal Zone, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China
| | - Jie Li
- Marine Engineering Environment and Geomatic Center, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China
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38
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Zhang Y, Qin W, Hou L, Zakem EJ, Wan X, Zhao Z, Liu L, Hunt KA, Jiao N, Kao SJ, Tang K, Xie X, Shen J, Li Y, Chen M, Dai X, Liu C, Deng W, Dai M, Ingalls AE, Stahl DA, Herndl GJ. Nitrifier adaptation to low energy flux controls inventory of reduced nitrogen in the dark ocean. Proc Natl Acad Sci U S A 2020; 117:4823-4830. [PMID: 32071230 PMCID: PMC7060736 DOI: 10.1073/pnas.1912367117] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Ammonia oxidation to nitrite and its subsequent oxidation to nitrate provides energy to the two populations of nitrifying chemoautotrophs in the energy-starved dark ocean, driving a coupling between reduced inorganic nitrogen (N) pools and production of new organic carbon (C) in the dark ocean. However, the relationship between the flux of new C production and the fluxes of N of the two steps of oxidation remains unclear. Here, we show that, despite orders-of-magnitude difference in cell abundances between ammonia oxidizers and nitrite oxidizers, the two populations sustain similar bulk N-oxidation rates throughout the deep waters with similarly high affinities for ammonia and nitrite under increasing substrate limitation, thus maintaining overall homeostasis in the oceanic nitrification pathway. Our observations confirm the theoretical predictions of a redox-informed ecosystem model. Using balances from this model, we suggest that consistently low ammonia and nitrite concentrations are maintained when the two populations have similarly high substrate affinities and their loss rates are proportional to their maximum growth rates. The stoichiometric relations between the fluxes of C and N indicate a threefold to fourfold higher C-fixation efficiency per mole of N oxidized by ammonia oxidizers compared to nitrite oxidizers due to nearly identical apparent energetic requirements for C fixation of the two populations. We estimate that the rate of chemoautotrophic C fixation amounts to ∼1 × 1013 to ∼2 × 1013 mol of C per year globally through the flux of ∼1 × 1014 to ∼2 × 1014 mol of N per year of the two steps of oxidation throughout the dark ocean.
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Affiliation(s)
- Yao Zhang
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China;
- College of Ocean and Earth Sciences, Xiamen University, 361101 Xiamen, China
| | - Wei Qin
- School of Oceanography, University of Washington, Seattle, WA 98195
| | - Lei Hou
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, 361101 Xiamen, China
| | - Emily J Zakem
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089
| | - Xianhui Wan
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China
| | - Zihao Zhao
- Department of Limnology and Bio-Oceanography, Center of Functional Ecology, University of Vienna, A-1090 Vienna, Austria
| | - Li Liu
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, 361101 Xiamen, China
| | - Kristopher A Hunt
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA 98195
| | - Nianzhi Jiao
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, 361101 Xiamen, China
| | - Shuh-Ji Kao
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, 361101 Xiamen, China
| | - Kai Tang
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, 361101 Xiamen, China
| | - Xiabing Xie
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China
| | - Jiaming Shen
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, 361101 Xiamen, China
| | - Yufang Li
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, 361101 Xiamen, China
| | - Mingming Chen
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, 361101 Xiamen, China
| | - Xiaofeng Dai
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, 361101 Xiamen, China
| | - Chang Liu
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, 361101 Xiamen, China
| | - Wenchao Deng
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China
| | - Minhan Dai
- State Key Laboratory of Marine Environmental Sciences, Xiamen University, 361101 Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, 361101 Xiamen, China
| | - Anitra E Ingalls
- School of Oceanography, University of Washington, Seattle, WA 98195
| | - David A Stahl
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA 98195
| | - Gerhard J Herndl
- Department of Limnology and Bio-Oceanography, Center of Functional Ecology, University of Vienna, A-1090 Vienna, Austria
- Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research, Utrecht University, 1790 AB Den Burg, The Netherlands
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Sun X, Kop LFM, Lau MCY, Frank J, Jayakumar A, Lücker S, Ward BB. Uncultured Nitrospina-like species are major nitrite oxidizing bacteria in oxygen minimum zones. THE ISME JOURNAL 2019; 13:2391-2402. [PMID: 31118472 PMCID: PMC6776041 DOI: 10.1038/s41396-019-0443-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 05/06/2019] [Accepted: 05/09/2019] [Indexed: 01/05/2023]
Abstract
Oxygen minimum zones (OMZs) are marine regions where O2 is undetectable at intermediate depths. Within OMZs, the oxygen-depleted zone (ODZ) induces anaerobic microbial processes that lead to fixed nitrogen loss via denitrification and anammox. Surprisingly, nitrite oxidation is also detected in ODZs, although all known marine nitrite oxidizers (mainly Nitrospina) are aerobes. We used metagenomic binning to construct metagenome-assembled genomes (MAGs) of nitrite oxidizers from OMZs. These MAGs represent two novel Nitrospina-like species, both of which differed from all known Nitrospina species, including cultured species and published MAGs. Relative abundances of different Nitrospina genotypes in OMZ and non-OMZ seawaters were estimated by mapping metagenomic reads to newly constructed MAGs and published high-quality genomes of members from the Nitrospinae phylum. The two novel species were present in all major OMZs and were more abundant inside ODZs, which is consistent with the detection of higher nitrite oxidation rates in ODZs than in oxic seawaters and suggests novel adaptations to anoxic environments. The detection of a large number of unclassified nitrite oxidoreductase genes in the dataset implies that the phylogenetic diversity of nitrite oxidizers is greater than previously thought.
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Affiliation(s)
- Xin Sun
- Department of Geosciences, Guyot Hall, Princeton University, Princeton, NJ, 08544, USA.
| | - Linnea F M Kop
- Department of Microbiology, Radboud University, Nijmegen, AJ, 6525, the Netherlands
| | - Maggie C Y Lau
- Department of Geosciences, Guyot Hall, Princeton University, Princeton, NJ, 08544, USA
- Laboratory of Extraterrestrial Ocean Systems, Institute of Deep-Sea Science and Engineering, Chinese Academic of Sciences, Sanya, Hainan, 572000, China
| | - Jeroen Frank
- Department of Microbiology, Radboud University, Nijmegen, AJ, 6525, the Netherlands
| | - Amal Jayakumar
- Department of Geosciences, Guyot Hall, Princeton University, Princeton, NJ, 08544, USA
| | - Sebastian Lücker
- Department of Microbiology, Radboud University, Nijmegen, AJ, 6525, the Netherlands
| | - Bess B Ward
- Department of Geosciences, Guyot Hall, Princeton University, Princeton, NJ, 08544, USA
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40
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Muck S, De Corte D, Clifford EL, Bayer B, Herndl GJ, Sintes E. Niche Differentiation of Aerobic and Anaerobic Ammonia Oxidizers in a High Latitude Deep Oxygen Minimum Zone. Front Microbiol 2019; 10:2141. [PMID: 31572345 PMCID: PMC6753893 DOI: 10.3389/fmicb.2019.02141] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 08/30/2019] [Indexed: 12/30/2022] Open
Abstract
To elucidate the potential for nitrification and denitrification processes in a high latitude deep oxygen minimum zone (OMZ) we determined the abundance and community composition of the main microbial players in the aerobic and anaerobic (anammox) ammonium oxidation and denitrification processes in the Gulf of Alaska throughout the water column. Within the dominant bacterial groups, Flavobacterales, Rhodobacterales, Actinomarinales, and SAR86 were more abundant in epipelagic waters and decreased with depth, whereas SAR11, SAR324, Marinimicrobia, and Thiomicrospirales increased their contribution to the bacterial community with depth. Nitrosopumilaceae also increased with depth and dominated the OMZ and bathypelagic archaeal communities. Euryarchaeota Marine Group II exhibited an opposite depth pattern to Nitrosopumilaceae, whereas Marine Group III and Woesearchaeota were more abundant in the bathypelagic realm. Candidatus Brocadia contributed 70-100% of the anammox bacterial community throughout the water column. Archaeal ammonia oxidizers (AOA) dominated the microbial community involved in the nitrogen cycle. Two AOA ecotypes, the high ammonia (HAC) and low ammonia (LAC)-AOA, characterized by distinct genes for aerobic ammonia oxidation (amoA) and for denitrification (nirK), exhibited a distinct distribution pattern related to depth and ammonia concentrations. HAC-AOA dominated in epipelagic (80.5 ± 28.3% of total AOA) oxygenated and ammonia-rich waters, and LAC-AOA dominated in the OMZ (90.9 ± 5.1%) and bathypelagic waters (85.5 ± 13.5%), characterized by lower oxygen and ammonia concentrations. Bacterial denitrifiers (3.7 ± 6.9 bacterial nirK gene mL-1) and anaerobic ammonia oxidizers (78 ± 322 anammox 16S rRNA genes L-1) were low in abundance under the oxygen conditions in the Gulf of Alaska throughout the water column. The widespread distribution of bacterial denitrifiers and anaerobic ammonia oxidizers in low abundances reveals a reservoir of genetic and metabolic potential ready to colonize the environment under the predicted increase of OMZs in the ocean. Taken together, our results reinforce the niche partitioning of archaeal ammonia oxidizers based on their distinct metabolic characteristics resulting in the dominance of LAC-AOA in a high latitude deep OMZ. Considering the different ecological roles and functions of the two archaeal ecotypes, the expansion of the zones dominated by the LAC-ecotype might have implications for the nitrogen cycle in the future ocean.
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Affiliation(s)
- Simone Muck
- Department of Limnology and Bio-Oceanography, Center of Functional Ecology, University of Vienna, Vienna, Austria
- NIOZ, Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research, Utrecht University, Den Burg, Netherlands
| | - Daniele De Corte
- Research and Development Center for Marine Biosciences, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan
| | - Elisabeth L. Clifford
- Department of Limnology and Bio-Oceanography, Center of Functional Ecology, University of Vienna, Vienna, Austria
| | - Barbara Bayer
- Department of Limnology and Bio-Oceanography, Center of Functional Ecology, University of Vienna, Vienna, Austria
| | - Gerhard J. Herndl
- Department of Limnology and Bio-Oceanography, Center of Functional Ecology, University of Vienna, Vienna, Austria
- NIOZ, Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research, Utrecht University, Den Burg, Netherlands
| | - Eva Sintes
- Department of Limnology and Bio-Oceanography, Center of Functional Ecology, University of Vienna, Vienna, Austria
- Ecosystem Oceanography Group (GRECO), Instituto Español de Oceanografía, Centro Oceanográfico de Baleares, Palma, Spain
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41
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Abstract
In the ocean's major oxygen minimum zones (OMZs), oxygen is effectively absent from sea water and life is dominated by microorganisms that use chemicals other than oxygen for respiration. Recent studies that combine advanced genomic and chemical detection methods are delineating the different metabolic niches that microorganisms can occupy in OMZs. Understanding these niches, the microorganisms that inhabit them, and their influence on marine biogeochemical cycles is crucial as OMZs expand with increasing seawater temperatures.
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Affiliation(s)
| | - Frank J Stewart
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA.
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42
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Haas S, Desai DK, LaRoche J, Pawlowicz R, Wallace DWR. Geomicrobiology of the carbon, nitrogen and sulphur cycles in Powell Lake: a permanently stratified water column containing ancient seawater. Environ Microbiol 2019; 21:3927-3952. [PMID: 31314947 DOI: 10.1111/1462-2920.14743] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 07/12/2019] [Accepted: 07/13/2019] [Indexed: 11/30/2022]
Abstract
We present the first geomicrobiological characterization of the meromictic water column of Powell Lake (British Columbia, Canada), a former fjord, which has been stably stratified since the last glacial period. Its deepest layers (300-350 m) retain isolated, relict seawater from that period. Fine-scale vertical profiling of the water chemistry and microbial communities allowed subdivision of the water column into distinct geomicrobiological zones. These zones were further characterized by phylogenetic and functional marker genes from amplicon and shotgun metagenome sequencing. Binning of metagenomic reads allowed the linkage of function to specific taxonomic groups. Statistical analyses (analysis of similarities, Bray-Curtis similarity) confirmed that the microbial community structure followed closely the geochemical zonation. Yet, our characterization of the genetic potential relevant to carbon, nitrogen and sulphur cycling of each zone revealed unexpected features, including potential for facultative anaerobic methylotrophy, nitrogen fixation despite high ammonium concentrations and potential micro-aerobic nitrifiers within the chemocline. At the oxic-suboxic interface, facultative anaerobic potential was found in the widespread freshwater lineage acI (Actinobacteria), suggesting intriguing ecophysiological similarities to the marine SAR11. Evolutionary divergent lineages among diverse phyla were identified in the ancient seawater zone and may indicate novel adaptations to this unusual environment.
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Affiliation(s)
- Sebastian Haas
- Department of Oceanography, Dalhousie University, 1355 Oxford Street, Halifax, Nova Scotia, Canada
| | - Dhwani K Desai
- Department of Biology, Dalhousie University, 1355 Oxford Street, Halifax, Nova Scotia, Canada
| | - Julie LaRoche
- Department of Biology, Dalhousie University, 1355 Oxford Street, Halifax, Nova Scotia, Canada
| | - Rich Pawlowicz
- Department of Earth and Ocean Sciences, University of British Columbia, 6339 Stores Road, Vancouver, British Columbia, Canada
| | - Douglas W R Wallace
- Department of Oceanography, Dalhousie University, 1355 Oxford Street, Halifax, Nova Scotia, Canada
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43
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Widner B, Fuchsman CA, Chang BX, Rocap G, Mulholland MR. Utilization of urea and cyanate in waters overlying and within the eastern tropical north Pacific oxygen deficient zone. FEMS Microbiol Ecol 2019; 94:5055141. [PMID: 30016420 DOI: 10.1093/femsec/fiy138] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 07/16/2018] [Indexed: 11/15/2022] Open
Abstract
In marine oxygen deficient zones (ODZs), which contribute up to half of marine N loss, microbes use nitrogen (N) for assimilatory and dissimilatory processes. Here, we examine N utilization above and within the ODZ of the Eastern Tropical North Pacific Ocean, focusing on distribution, uptake and genes for the utilization of two simple organic N compounds, urea and cyanate. Ammonium, urea and cyanate concentrations generally peaked in the oxycline while uptake rates were highest in the surface. Within the ODZ, concentrations were lower, but urea N and C and cyanate C were taken up. All identified autotrophs had an N assimilation pathway that did not require external ammonium: ODZ Prochlorococcus possessed genes to assimilate nitrate, nitrite and urea; nitrite oxidizers (Nitrospina) possessed genes to assimilate nitrite, urea and cyanate; anammox bacteria (Scalindua) possessed genes to utilize cyanate; and ammonia-oxidizing Thaumarchaeota possessed genes to utilize urea. Urease genes were present in 20% of microbes, including SAR11, suggesting the urea utilization capacity was widespread. In the ODZ core, cyanate genes were largely (∼95%) associated with Scalindua, suggesting that, within this ODZ, cyanate N is primarily used for N loss via anammox (cyanammox), and that anammox does not require ammonium for N loss.
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Affiliation(s)
- Brittany Widner
- Department of Ocean, Earth and Atmospheric Sciences, Old Dominion University, Norfolk, USA
| | - Clara A Fuchsman
- University of Washington, School of Oceanography, Seattle, USA.,Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, USA
| | - Bonnie X Chang
- Joint Institute for the Study of the Atmosphere and Ocean, University of Washington, Seattle, USA.,Pacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, Seattle, USA
| | - Gabrielle Rocap
- University of Washington, School of Oceanography, Seattle, USA
| | - Margaret R Mulholland
- Department of Ocean, Earth and Atmospheric Sciences, Old Dominion University, Norfolk, USA
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44
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The water depth-dependent co-occurrence patterns of marine bacteria in shallow and dynamic Southern Coast, Korea. Sci Rep 2019; 9:9176. [PMID: 31235719 PMCID: PMC6591218 DOI: 10.1038/s41598-019-45512-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 06/04/2019] [Indexed: 01/05/2023] Open
Abstract
To investigate the interactions between bacterial species in relation to the biotic and abiotic environmental fluctuations, free-living (FL), nanoparticle-associated (NP), and microparticle-associated (MP) bacterial community compositions (BCCs) were analyzed. A total of 267 samples were collected from July to December 2016 in the dynamic and shallow southern coastal water of Korea. The variations in BCC mostly depended on planktonic size fraction. Network analysis revealed water depth-dependent co-occurrence patterns of coastal bacterial communities. Higher interspecies connectivity was observed within FL bacteria than NP/MP bacteria, suggesting that FL bacteria with a streamlined genome may need other bacterial metabolites for survival, while the NP/MP copiotrophs may have the self-supporting capacity to produce the vital nutrients. The analysis of topological roles of individual OTUs in the network revealed that several groups of metabolically versatile bacteria (the marine Roseobacters, Flavobacteriales, Desulfobacterales, and SAR406 clade) acted as module hubs in different water depth. In conclusion, interspecies interactions dominated in FL bacteria, compared to NP and MP bacteria; modular structures of bacterial communities and keystone species strongly depended on the water depth-derived environmental factors. Furthermore, the multifunctional, versatile FL bacteria could play pivotal roles in dynamic shallow coastal ecosystems.
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45
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Saunders JK, Fuchsman CA, McKay C, Rocap G. Complete arsenic-based respiratory cycle in the marine microbial communities of pelagic oxygen-deficient zones. Proc Natl Acad Sci U S A 2019; 116:9925-9930. [PMID: 31036654 PMCID: PMC6525544 DOI: 10.1073/pnas.1818349116] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Microbial capacity to metabolize arsenic is ancient, arising in response to its pervasive presence in the environment, which was largely in the form of As(III) in the early anoxic ocean. Many biological arsenic transformations are aimed at mitigating toxicity; however, some microorganisms can respire compounds of this redox-sensitive element to reap energetic gains. In several modern anoxic marine systems concentrations of As(V) are higher relative to As(III) than what would be expected from the thermodynamic equilibrium, but the mechanism for this discrepancy has remained unknown. Here we present evidence of a complete respiratory arsenic cycle, consisting of dissimilatory As(V) reduction and chemoautotrophic As(III) oxidation, in the pelagic ocean. We identified the presence of genes encoding both subunits of the respiratory arsenite oxidase AioA and the dissimilatory arsenate reductase ArrA in the Eastern Tropical North Pacific (ETNP) oxygen-deficient zone (ODZ). The presence of the dissimilatory arsenate reductase gene arrA was enriched on large particles (>30 um), similar to the forward bacterial dsrA gene of sulfate-reducing bacteria, which is involved in the cryptic cycling of sulfur in ODZs. Arsenic respiratory genes were expressed in metatranscriptomic libraries from the ETNP and the Eastern Tropical South Pacific (ETSP) ODZ, indicating arsenotrophy is a metabolic pathway actively utilized in anoxic marine water columns. Together these results suggest arsenic-based metabolisms support organic matter production and impact nitrogen biogeochemical cycling in modern oceans. In early anoxic oceans, especially during periods of high marine arsenic concentrations, they may have played a much larger role.
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Affiliation(s)
| | - Clara A Fuchsman
- School of Oceanography, University of Washington, Seattle, WA 98195
| | - Cedar McKay
- School of Oceanography, University of Washington, Seattle, WA 98195
| | - Gabrielle Rocap
- School of Oceanography, University of Washington, Seattle, WA 98195
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46
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Cohen Y, Pasternak Z, Johnke J, Abed‐Rabbo A, Kushmaro A, Chatzinotas A, Jurkevitch E. Bacteria and microeukaryotes are differentially segregated in sympatric wastewater microhabitats. Environ Microbiol 2019; 21:1757-1770. [DOI: 10.1111/1462-2920.14548] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 01/20/2019] [Accepted: 01/28/2019] [Indexed: 01/22/2023]
Affiliation(s)
- Yossi Cohen
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and EnvironmentThe Hebrew University of Jerusalem Rehovot, 76100 Israel
| | - Zohar Pasternak
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and EnvironmentThe Hebrew University of Jerusalem Rehovot, 76100 Israel
| | - Julia Johnke
- Department of Environmental MicrobiologyHelmholtz Centre for Environmental Research – UFZ Permoserstrasse 15, Leipzig, 04318 Germany
| | - Alfred Abed‐Rabbo
- Faculty of ScienceBethlehem University, Palestinian National Authority, Bethlehem, Israel
| | - Ariel Kushmaro
- Avram and Stella Goldstein‐Goren, The Department of Biotechnology Engineering, Faculty of Engineering SciencesBen‐Gurion University of the Negev P.O. Box 653, Beer‐Sheva Israel
- The Ilse Katz Centre for Meso and Nanoscale Science and TechnologyBen‐Gurion University of the Negev Beer‐Sheva Israel
| | - Antonis Chatzinotas
- Department of Environmental MicrobiologyHelmholtz Centre for Environmental Research – UFZ Permoserstrasse 15, Leipzig, 04318 Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig Deutscher Platz 5e, Leipzig, 04103 Germany
| | - Edouard Jurkevitch
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and EnvironmentThe Hebrew University of Jerusalem Rehovot, 76100 Israel
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47
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Dick JM, Yu M, Tan J, Lu A. Changes in Carbon Oxidation State of Metagenomes Along Geochemical Redox Gradients. Front Microbiol 2019; 10:120. [PMID: 30804909 PMCID: PMC6378307 DOI: 10.3389/fmicb.2019.00120] [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] [Received: 08/31/2018] [Accepted: 01/18/2019] [Indexed: 01/01/2023] Open
Abstract
There is widespread interest in how geochemistry affects the genomic makeup of microbial communities, but the possible impacts of oxidation-reduction (redox) conditions on the chemical composition of biomacromolecules remain largely unexplored. Here we document systematic changes in the carbon oxidation state, a metric derived from the chemical formulas of biomacromolecular sequences, using published metagenomic and metatranscriptomic datasets from 18 studies representing different marine and terrestrial environments. We find that the carbon oxidation states of DNA, as well as proteins inferred from coding sequences, follow geochemical redox gradients associated with mixing and cooling of hot spring fluids in Yellowstone National Park (USA) and submarine hydrothermal fluids. Thermodynamic calculations provide independent predictions for the environmental shaping of the gene and protein composition of microbial communities in these systems. On the other hand, the carbon oxidation state of DNA is negatively correlated with oxygen concentration in marine oxygen minimum zones. In this case, a thermodynamic model is not viable, but the low carbon oxidation state of DNA near the ocean surface reflects a low GC content, which can be attributed to genome reduction in organisms adapted to low-nutrient conditions. We also present evidence for a depth-dependent increase of oxidation state at the species level, which might be associated with alteration of DNA through horizontal gene transfer and/or selective degradation of relatively reduced (AT-rich) extracellular DNA by heterotrophic bacteria. Sediments exhibit even more complex behavior, where carbon oxidation state minimizes near the sulfate-methane transition zone and rises again at depth; markedly higher oxidation states are also associated with older freshwater-dominated sediments in the Baltic Sea that are enriched in iron oxides and have low organic carbon. This geobiochemical study of carbon oxidation state reveals a new aspect of environmental information in metagenomic sequences, and provides a reference frame for future studies that may use ancient DNA sequences as a paleoredox indicator.
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Affiliation(s)
- Jeffrey M. Dick
- Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Ministry of Education, Central South University, Changsha, China
- School of Geosciences and Info-Physics, Central South University, Changsha, China
| | - Miao Yu
- Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Ministry of Education, Central South University, Changsha, China
- School of Geosciences and Info-Physics, Central South University, Changsha, China
| | - Jingqiang Tan
- Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Ministry of Education, Central South University, Changsha, China
- School of Geosciences and Info-Physics, Central South University, Changsha, China
| | - Anhuai Lu
- Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Ministry of Education, Central South University, Changsha, China
- School of Geosciences and Info-Physics, Central South University, Changsha, China
- School of Earth and Space Sciences, Peking University, Beijing, China
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48
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Aires T, Muyzer G, Serrão EA, Engelen AH. Seaweed Loads Cause Stronger Bacterial Community Shifts in Coastal Lagoon Sediments Than Nutrient Loads. Front Microbiol 2019; 9:3283. [PMID: 30687271 PMCID: PMC6333863 DOI: 10.3389/fmicb.2018.03283] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 12/17/2018] [Indexed: 11/23/2022] Open
Abstract
The input of nutrients from anthropogenic sources is the leading cause of coastal eutrophication and is usually coupled with algal/seaweed blooms. Effects may be magnified in semi-enclosed systems, such as highly productive coastal lagoon ecosystems. Eutrophication and seaweed blooms can lead to ecosystem disruption. Previous studies have considered only one of these factors, disregarding possible interactive effects and the effect of the blooming species' identity on sediment bacterial communities. We tested the effect of experimental nutrient loading and two common blooming seaweeds (Ulva rigida and Gracilaria vermiculophylla) in coastal lagoon sediments, on the structure of bacterial communities (using 16S rRNA amplicon sequencing) and corresponding putative functional potential (using PiCRUSt). At the Operational Taxonomic Unit (OTU) level, the addition of nutrients reduced bacterial community α-diversity and decreased the abundance of sulfate reducers (Desulfobacterales) compared to sulfur oxidizers/denitrifiers (Chromatiales and Campylobacterales), whereas this was not the case at the order level. Seaweed addition did not change bacterial α-diversity and the effect on community structure depended on the taxonomic level considered. The addition of Gracilaria increased the abundance of orders and OTUs involved in sulfate reduction and organic matter decomposition (Desulfobacterales, Bacteroidales, and Clostridiales, respectively), an effect which was also detected when only Ulva was added. Nutrients and the seaweeds combined only interacted for Ulva and nutrients, which increased known sulfide oxidizers and denitrifiers (order Campylobacterales). Seaweed enrichment affected putative functional profiles; a stronger increase of sulfur cycling KEGG pathways was assigned to nutrient-disturbed sediments, particularly with the seaweeds and especially Ulva. In contrast, nitrogen and sulfur cycle pathways showed a higher abundance of genes related to dissimilatory nitrate reduction to ammonium (DNRA) in Ulva+nutrients treatments. However, the other seaweed treatments increased the nitrogen fixation genes. Thiosulfate reduction, performed by sulfate-reducing bacteria, increased in seaweed treatments except when Ulva was combined with nutrients. In conclusion, the in situ addition of nutrients and the seaweeds to intertidal sediments affected the bacterial communities differently and independently. The predicted functional profile suggests a shift in relative abundances of putative pathways for nitrogen and sulfur cycles, in line with the taxonomic changes of the bacterial communities.
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Affiliation(s)
- Tânia Aires
- Centro de Ciências do Mar (CCMAR), Centro de Investigação Marinha e Ambiental (CIMAR), Universidade do Algarve, Faro, Portugal
| | - Gerard Muyzer
- Microbial Systems Ecology, Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, Netherlands
| | - Ester A. Serrão
- Centro de Ciências do Mar (CCMAR), Centro de Investigação Marinha e Ambiental (CIMAR), Universidade do Algarve, Faro, Portugal
| | - Aschwin H. Engelen
- Centro de Ciências do Mar (CCMAR), Centro de Investigação Marinha e Ambiental (CIMAR), Universidade do Algarve, Faro, Portugal
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49
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Easson CG, Lopez JV. Depth-Dependent Environmental Drivers of Microbial Plankton Community Structure in the Northern Gulf of Mexico. Front Microbiol 2019; 9:3175. [PMID: 30662434 PMCID: PMC6328475 DOI: 10.3389/fmicb.2018.03175] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 12/07/2018] [Indexed: 02/01/2023] Open
Abstract
The Gulf of Mexico (GoM) is a dynamic marine ecosystem influenced by multiple natural and anthropogenic processes and inputs, such as the intrusion of warm oligotrophic water via the Loop Current, freshwater and nutrient input by the Mississippi River, and hydrocarbon inputs via natural seeps and industrial spills. Microbial plankton communities are important to pelagic food webs including in the GoM but understanding the drivers of the natural dynamics of these passively distributed microorganisms can be challenging in such a large and heterogeneous system. As part of the DEEPEND consortium, we applied high throughput 16S rRNA sequencing to investigate the spatial and temporal dynamics of pelagic microbial plankton related to several environmental conditions during two offshore cruises in 2015. Our results show dramatic community shifts across depths, especially between photic and aphotic zones. Though we only have two time points within a single year, observed temporal shifts in microbial plankton communities were restricted to the seasonally influenced epipelagic zone (0-200 m), and appear mainly driven by changes in temperature. Environmental selection in microbial plankton communities was depth-specific, with variables such as turbidity, salinity, and abundance of photosynthetic taxa strongly correlating with community structure in the epipelagic zone, while variables such as oxygen and specific nutrient concentrations were correlated with community structure at deeper depths.
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Affiliation(s)
- Cole G. Easson
- Department of Biology, Middle Tennessee State University, Murfreesboro, TN, United States
| | - Jose V. Lopez
- Halmos College of Natural Sciences and Oceanography, Nova Southeastern University, Dania Beach, FL, United States
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50
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Jing H, Zhu W, Liu H, Zheng L, Zhang Y. Particle-Attached and Free-Living Archaeal Communities in the Benthic Boundary Layer of the Mariana Trench. Front Microbiol 2018; 9:2821. [PMID: 30519228 PMCID: PMC6258811 DOI: 10.3389/fmicb.2018.02821] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Accepted: 11/02/2018] [Indexed: 01/29/2023] Open
Abstract
The benthic boundary layer (BBL) is the part of the water column that is situated near to the sediment surface, where active oceanic biogeochemical cycling occurs. Archaea play an important role in mediating this cycling, however, their composition and diversity in the BBL remain largely unknown. We investigated the community composition and abundance of both particle-attached (PA) and free-living (FL) archaea in the BBL on the slopes of the Mariana Trench using Illumina sequencing and quantitative PCR (qPCR), at both the DNA and RNA levels. Our results showed that Thaumarchaeota (>90%) and Woesearchaeota (1–10%) dominated in all the BBL samples, and that the former was composed mainly of Marine Group I (MGI). A clear separation of PA and FL samples was observed, and they showed a high level of similarity to the subsurface sediments and the water column, respectively. No significant differences were detected in the archaeal communities located in the southern and northern slopes of the Mariana Trench, or between the levels of DNA and RNA. However, lower RNA/DNA ratios (estimated by qPCR) were found in the PA samples than in the FL samples, indicating higher transcriptional activities in the FL fractions. A distinct archaeal community structure was found in the middle of the trench when compared with samples collected at the same depth at other stations along the trench slopes. This indicates that a dynamic deep current might affect the distribution of organic matter on the slopes. Our study provides direct information regarding the archaeal communities in the BBL of the Mariana Trench. We suggest that this might promote further exploration of the ecological roles and microbial processes of such communities located in deep-sea ecosystems.
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Affiliation(s)
- Hongmei Jing
- CAS Key Lab for Experimental Study Under Deep-sea Extreme Conditions, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | - Wenda Zhu
- CAS Key Lab for Experimental Study Under Deep-sea Extreme Conditions, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Hongbin Liu
- Division of Life Science, The Hong Kong University of Science and Technology, Kowloon, China
| | - Liping Zheng
- CAS Key Lab for Experimental Study Under Deep-sea Extreme Conditions, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | - Yu Zhang
- State Key Laboratory of Ocean Engineering, Institute of Oceanography, Shanghai Jiao Tong University, Shanghai, China
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