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Letourneau J, Carrion VM, Jiang S, Osborne OW, Holmes ZC, Fox A, Epstein P, Tan CY, Kirtley M, Surana NK, David LA. Interplay between particle size and microbial ecology in the gut microbiome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.26.591376. [PMID: 38712077 PMCID: PMC11071529 DOI: 10.1101/2024.04.26.591376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Physical particles can serve as critical abiotic factors that structure the ecology of microbial communities. For non-human vertebrate gut microbiomes, fecal particle size (FPS) has been known to be shaped by chewing efficiency and diet. However, little is known about what drives FPS in the human gut. Here, we analyzed FPS by laser diffraction across a total of 76 individuals and found FPS to be strongly individualized. Surprisingly, a behavioral intervention with 41 volunteers designed to increase chewing efficiency did not impact FPS. Dietary patterns could also not be associated with FPS. Instead, we found evidence that mammalian and human gut microbiomes shaped FPS. Fecal samples from germ-free and antibiotic-treated mice exhibited increased FPS relative to colonized mice. In humans, markers of longer transit time were correlated with smaller FPS. Gut microbiota diversity and composition were also associated with FPS. Finally, ex vivo culture experiments using human fecal microbiota from distinct donors showed that differences in microbiota community composition can drive variation in particle size. Together, our results support an ecological model in which the human gut microbiome plays a key role in reducing the size of food particles during digestion, and that the microbiomes of individuals vary in this capacity. These new insights also suggest FPS in humans to be governed by processes beyond those found in other mammals and emphasize the importance of gut microbiota in shaping their own abiotic environment.
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Affiliation(s)
- Jeffrey Letourneau
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
| | - Verónica M Carrion
- Duke Office of Clinical Research, Duke University School of Medicine, Durham, NC 27710
| | - Sharon Jiang
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
| | - Olivia W Osborne
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
| | - Zachary C Holmes
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
| | - Aiden Fox
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
| | - Piper Epstein
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
| | - Chin Yee Tan
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
- Department of Pediatrics, Duke University School of Medicine, Durham, NC 27710
| | - Michelle Kirtley
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
| | - Neeraj K Surana
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
- Department of Pediatrics, Duke University School of Medicine, Durham, NC 27710
- Department of Integrative Immunobiology, Duke University School of Medicine, Durham, NC 27710
- Duke Microbiome Center, Duke University School of Medicine, Durham, NC 27710
| | - Lawrence A David
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710
- Duke Microbiome Center, Duke University School of Medicine, Durham, NC 27710
- Program in Computational Biology and Bioinformatics, Duke University School of Medicine, Durham, NC 27710
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2
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Wietz M, Engel A, Ramondenc S, Niwano M, von Appen WJ, Priest T, von Jackowski A, Metfies K, Bienhold C, Boetius A. The Arctic summer microbiome across Fram Strait: Depth, longitude, and substrate concentrations structure microbial diversity in the euphotic zone. Environ Microbiol 2024; 26:e16568. [PMID: 38268397 DOI: 10.1111/1462-2920.16568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 12/12/2023] [Indexed: 01/26/2024]
Abstract
The long-term dynamics of microbial communities across geographic, hydrographic, and biogeochemical gradients in the Arctic Ocean are largely unknown. To address this, we annually sampled polar, mixed, and Atlantic water masses of the Fram Strait (2015-2019; 5-100 m depth) to assess microbiome composition, substrate concentrations, and oceanographic parameters. Longitude and water depth were the major determinants (~30%) of microbial community variability. Bacterial alpha diversity was highest in lower-photic polar waters. Community composition shifted from west to east, with the prevalence of, for example, Dadabacteriales and Thiotrichales in Arctic- and Atlantic-influenced waters, respectively. Concentrations of dissolved organic carbon peaked in the western, compared to carbohydrates in the chlorophyll-maximum of eastern Fram Strait. Interannual differences due to the time of sampling, which varied between early (June 2016/2018) and late (September 2019) phytoplankton bloom stages, illustrated that phytoplankton composition and resulting availability of labile substrates influence bacterial dynamics. We identified 10 species clusters with stable environmental correlations, representing signature populations of distinct ecosystem states. In context with published metagenomic evidence, our microbial-biogeochemical inventory of a key Arctic region establishes a benchmark to assess ecosystem dynamics and the imprint of climate change.
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Affiliation(s)
- Matthias Wietz
- Deep-Sea Ecology and Technology, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Anja Engel
- Biological Oceanography, GEOMAR Helmholtz Centre for Ocean Research, Kiel, Germany
| | - Simon Ramondenc
- Deep-Sea Ecology and Technology, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Matomo Niwano
- Deep-Sea Ecology and Technology, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Wilken-Jon von Appen
- Physical Oceanography of the Polar Seas, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Taylor Priest
- Max Planck Institute for Marine Microbiology, Bremen, Germany
- Institute of Microbiology, ETH Zurich, Zurich, Switzerland
| | - Anabel von Jackowski
- Biological Oceanography, GEOMAR Helmholtz Centre for Ocean Research, Kiel, Germany
| | - Katja Metfies
- Polar Biological Oceanography, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg, Oldenburg, Germany
| | - Christina Bienhold
- Deep-Sea Ecology and Technology, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Antje Boetius
- Deep-Sea Ecology and Technology, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
- Max Planck Institute for Marine Microbiology, Bremen, Germany
- MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
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3
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Stephens BM, Durkin CA, Sharpe G, Nguyen TTH, Albers J, Estapa ML, Steinberg DK, Levine NM, Gifford SM, Carlson CA, Boyd PW, Santoro AE. Direct observations of microbial community succession on sinking marine particles. THE ISME JOURNAL 2024; 18:wrad010. [PMID: 38365233 PMCID: PMC10811735 DOI: 10.1093/ismejo/wrad010] [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: 11/06/2023] [Revised: 11/10/2023] [Accepted: 11/15/2023] [Indexed: 02/18/2024]
Abstract
Microbial community dynamics on sinking particles control the amount of carbon that reaches the deep ocean and the length of time that carbon is stored, with potentially profound impacts on Earth's climate. A mechanistic understanding of the controls on sinking particle distributions has been hindered by limited depth- and time-resolved sampling and methods that cannot distinguish individual particles. Here, we analyze microbial communities on nearly 400 individual sinking particles in conjunction with more conventional composite particle samples to determine how particle colonization and community assembly might control carbon sequestration in the deep ocean. We observed community succession with corresponding changes in microbial metabolic potential on the larger sinking particles transporting a significant fraction of carbon to the deep sea. Microbial community richness decreased as particles aged and sank; however, richness increased with particle size and the attenuation of carbon export. This suggests that the theory of island biogeography applies to sinking marine particles. Changes in POC flux attenuation with time and microbial community composition with depth were reproduced in a mechanistic ecosystem model that reflected a range of POC labilities and microbial growth rates. Our results highlight microbial community dynamics and processes on individual sinking particles, the isolation of which is necessary to improve mechanistic models of ocean carbon uptake.
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Affiliation(s)
- Brandon M Stephens
- Department of Ecology, Evolution and Marine Biology, Marine Science Institute, University of California, Santa Barbara, CA 93106, United States
- Present address: Institute of Oceanography, National Taiwan University, Taipei 106, Taiwan
| | - Colleen A Durkin
- Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039, United States
| | - Garrett Sharpe
- Department of Earth, Marine, and Environmental Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States
| | - Trang T H Nguyen
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, United States
- Department of Integrated Sciences, Fulbright University Vietnam, Ho Chi Minh City 756000, Vietnam
| | - Justine Albers
- Department of Ecology, Evolution and Marine Biology, Marine Science Institute, University of California, Santa Barbara, CA 93106, United States
| | - Margaret L Estapa
- School of Marine Sciences, Darling Marine Center, University of Maine, Walpole, ME 04573, United States
| | - Deborah K Steinberg
- Coastal & Ocean Processes Section, Virginia Institute of Marine Science, William & Mary, Gloucester Point, VA 23062, United States
| | - Naomi M Levine
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, United States
| | - Scott M Gifford
- Department of Earth, Marine, and Environmental Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, United States
| | - Craig A Carlson
- Department of Ecology, Evolution and Marine Biology, Marine Science Institute, University of California, Santa Barbara, CA 93106, United States
| | - Philip W Boyd
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Alyson E Santoro
- Department of Ecology, Evolution and Marine Biology, Marine Science Institute, University of California, Santa Barbara, CA 93106, United States
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4
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LeCleir GR, Bassett J, Wilhelm SW. Effects of iron concentration and DFB (Desferrioxamine-B) on transcriptional profiles of an ecologically relevant marine bacterium. PLoS One 2023; 18:e0295257. [PMID: 38100448 PMCID: PMC10723695 DOI: 10.1371/journal.pone.0295257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 11/20/2023] [Indexed: 12/17/2023] Open
Abstract
Research into marine iron cycles and biogeochemistry has commonly relied on the use of chelators (including siderophores) to manipulate iron bioavailability. To test whether a commonly used chelator, desferrioxamine B (DFB) caused effects beyond changing the iron-status of cells, cultures of the environmentally relevant marine heterotrophic bacterium, Ruegeria pomeroyii, were grown in media with different concentrations of iron and/or DFB, resulting in a gradient of iron availability. To determine how cells responded, transcriptomes were generated for cells from the different treatments and analyzed to determine how cells reacted to these to perturbations. Analyses were also performed to look for cellular responses specific to the presence of DFB in the culture medium. As expected, cells experiencing different levels of iron availability had different transcriptomic profiles. While many genes related to iron acquisition were differentially expressed between treatments, there were many other genes that were also differentially expressed between different sample types, including those related to the uptake and metabolism of other metals as well as genes related to metabolism of other types of molecules like amino acids and carbohydrates. We conclude that while DFB certainly altered iron availability to cells, it also appears to have had a general effect on the homeostasis of other metals as well as influenced metabolic processes outside of metal acquisition.
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Affiliation(s)
- Gary R. LeCleir
- Department of Microbiology, The University of Tennessee, Knoxville, Tennessee, United States of America
| | - Jenna Bassett
- Department of Microbiology, The University of Tennessee, Knoxville, Tennessee, United States of America
| | - Steven W. Wilhelm
- Department of Microbiology, The University of Tennessee, Knoxville, Tennessee, United States of America
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5
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Liu S, Hu R, Strong PJ, Saleem M, Zhou Z, Luo Z, Wu Y, He Z, Wang C. Vertical connectivity of microbiome and metabolome reveals depth-dependent variations across a deep cold-seep water column. ENVIRONMENTAL RESEARCH 2023; 239:117310. [PMID: 37805181 DOI: 10.1016/j.envres.2023.117310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 10/03/2023] [Accepted: 10/04/2023] [Indexed: 10/09/2023]
Abstract
Deciphering the vertical connectivity of oceanic microbiome and metabolome is crucial for understanding the carbon sequestration and achieving the carbon neutrality. However, we lack a systematic view of the interplay among particle transport, microbial community, and metabolic trait across depths. Through integrating the biogeochemical, microbial, and metabolic characteristics of a deep cold-seep water column (∼1989 m), we find the altered connectivity of microbial community and dissolved organic matter (DOM) across depths. Both the microbial communities (bacteria and protists) and DOM show a clear compositional connectivity from surface to the depth of 1000 m, highlighting the controls of sinking particle over microbial connectivity from the epipelagic to mesopelagic zone. However, due to the biological migration and ocean mixing, the fecal-associated bacteria and protistan consumers unexpectedly emerge and the degradation index of DOM substantially alters around 1000-1200 m. Collectively, we unveil the significance of multi-faceted particle dispersion, which supports the connectivity and variability of deep ocean microbial communities.
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Affiliation(s)
- Songfeng Liu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Ruiwen Hu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - P J Strong
- School of Biology and Environmental Science, Centre for Agriculture and the Bioeconomy, Queensland University of Technology, Brisbane, QLD, 4001, Australia
| | - Muhammad Saleem
- Department of Biological Sciences, Alabama State University, Montgomery, AL, 36104, USA
| | - Zhengyuan Zhou
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Zhiwen Luo
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Yongjie Wu
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510530, PR China
| | - Zhili He
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Cheng Wang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China.
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6
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Li F, Burger A, Eppley JM, Poff KE, Karl DM, DeLong EF. Planktonic microbial signatures of sinking particle export in the open ocean's interior. Nat Commun 2023; 14:7177. [PMID: 37935690 PMCID: PMC10630432 DOI: 10.1038/s41467-023-42909-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 10/25/2023] [Indexed: 11/09/2023] Open
Abstract
A considerable amount of particulate carbon produced by oceanic photosynthesis is exported to the deep-sea by the "gravitational pump" (~6.8 to 7.7 Pg C/year), sequestering it from the atmosphere for centuries. How particulate organic carbon (POC) is transformed during export to the deep sea however is not well understood. Here, we report that dominant suspended prokaryotes also found in sinking particles serve as informative tracers of particle export processes. In a three-year time series from oceanographic campaigns in the Pacific Ocean, upper water column relative abundances of suspended prokaryotes entrained in sinking particles decreased exponentially from depths of 75 to 250 m, conforming to known depth-attenuation patterns of carbon, energy, and mass fluxes in the epipelagic zone. Below ~250 m however, the relative abundance of suspended prokaryotes entrained in sinking particles increased with depth. These results indicate that microbial entrainment, colonization, and sinking particle formation are elevated at mesopelagic and bathypelagic depths. Comparison of suspended and sinking particle-associated microbes provides information about the depth-variability of POC export and biotic processes, that is not evident from biogeochemical data alone.
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Affiliation(s)
- Fuyan Li
- Department of Oceanography, University of Hawai'i at Mānoa, Honolulu, HI, USA
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Andrew Burger
- Department of Oceanography, University of Hawai'i at Mānoa, Honolulu, HI, USA
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - John M Eppley
- Department of Oceanography, University of Hawai'i at Mānoa, Honolulu, HI, USA
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Kirsten E Poff
- Department of Oceanography, University of Hawai'i at Mānoa, Honolulu, HI, USA
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, University of Hawai'i at Mānoa, Honolulu, HI, USA
- McDonogh School, Owings Mills, MD, USA
| | - David M Karl
- Department of Oceanography, University of Hawai'i at Mānoa, Honolulu, HI, USA
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Edward F DeLong
- Department of Oceanography, University of Hawai'i at Mānoa, Honolulu, HI, USA.
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, University of Hawai'i at Mānoa, Honolulu, HI, USA.
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7
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Zhang X, Cui L, Liu S, Li J, Wu Y, Ren Y, Huang X. Seasonal dynamics of bacterial community and co-occurrence with eukaryotic phytoplankton in the Pearl River Estuary. MARINE ENVIRONMENTAL RESEARCH 2023; 192:106193. [PMID: 37832281 DOI: 10.1016/j.marenvres.2023.106193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Revised: 08/23/2023] [Accepted: 09/20/2023] [Indexed: 10/15/2023]
Abstract
In this study, we investigated the taxonomic composition of the bacteria and phytoplankton communities in the Pearl River Estuary (PRE) through Illumina sequencing of the V3-V4 region of the 16 S rRNA gene. Furthermore, their relationships as well as recorded environmental variables were explored by co-occurrence networks. Bacterial community composition was different in two size fractions, as well as along the salinity gradient across two seasons. Free-living (FL) communities were dominated by pico-sized Cyanobacteria (Synechococcus CC9902) while Exiguobacterium, Halomonas and Pseudomonas were predominantly associated with particle-associated (PA) lifestyle, and Cyanobium PCC-6307 exhibited seasonal shifts in lifestyles in different seasons. In wet season, bacterial community composition was characterized by abundance of Cyanobacteria, Actinobacteria, and Bacteroidetes, which were tightly linked with high riverine inflow. While in dry season, Proteobacteria increased in prevalence, especially for Psychrobacter, NOR5/OM60 clade and Pseudomonas, which were thrived in lower water temperature and higher salinity. Moreover, we discovered that differences between PA and FL composition were more significant in the wet season than in the dry season, which may be due to better nutritional conditions of particles (indicated by POC%) in the wet season and then attract more diverse PA populations. Based on the analysis of plastidial 16 S rRNA genes, abundant small-sized mixotrophic phytoplankton (Dinophyceae, Euglenida and Haptophyta) were identified in the PRE. The complexity of co-occurrence network increased from FL to PA fractions in both seasons, which suggested that suspended particles can provide ecological niches for particle-associated colonizers contributing to the maintenance of a more stable community structure. In addition, the majority of phytoplankton species exhibited positive co-occurrences with both other phytoplankton species and bacterial counterparts, indicating the mutual cooperation between phytoplankton assemblages and specific bacterial populations e likely benefited from phytoplankton-derived organic compounds. This study enhances our understanding of the seasonal and spatial dynamics of bacterial communities and their potential relationship with phytoplankton assembly in estuarine waters.
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Affiliation(s)
- Xia Zhang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, China; Guangdong Provincial Key Laboratory of Applied Marine Biology, Guangzhou, 510301, China
| | - Lijun Cui
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, China; Guangdong Provincial Key Laboratory of Applied Marine Biology, Guangzhou, 510301, China
| | - Songlin Liu
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, China; Guangdong Provincial Key Laboratory of Applied Marine Biology, Guangzhou, 510301, China
| | - Jinlong Li
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, China; Guangdong Provincial Key Laboratory of Applied Marine Biology, Guangzhou, 510301, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yunchao Wu
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, China; Guangdong Provincial Key Laboratory of Applied Marine Biology, Guangzhou, 510301, China
| | - Yuzheng Ren
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, China; Guangdong Provincial Key Laboratory of Applied Marine Biology, Guangzhou, 510301, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaoping Huang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, China; Guangdong Provincial Key Laboratory of Applied Marine Biology, Guangzhou, 510301, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
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8
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Winners and Losers of Atlantification: The Degree of Ocean Warming Affects the Structure of Arctic Microbial Communities. Genes (Basel) 2023; 14:genes14030623. [PMID: 36980894 PMCID: PMC10048660 DOI: 10.3390/genes14030623] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/24/2023] [Accepted: 02/25/2023] [Indexed: 03/06/2023] Open
Abstract
Arctic microbial communities (i.e., protists and bacteria) are increasingly subjected to an intrusion of new species via Atlantification and an uncertain degree of ocean warming. As species differ in adaptive traits, these oceanic conditions may lead to compositional changes with functional implications for the ecosystem. In June 2021, we incubated water from the western Fram Strait at three temperatures (2 °C, 6 °C, and 9 °C), mimicking the current and potential future properties of the Arctic Ocean. Our results show that increasing the temperature to 6 °C only minorly affects the community, while an increase to 9 °C significantly lowers the diversity and shifts the composition. A higher relative abundance of large hetero- and mixotrophic protists was observed at 2 °C and 6 °C compared to a higher abundance of intermediate-sized temperate diatoms at 9 °C. The compositional differences at 9 °C led to a higher chlorophyll a:POC ratio, but the C:N ratio remained similar. Our results contradict the common assumption that smaller organisms and heterotrophs are favored under warming and strongly indicate a thermal limit between 6 °C and 9 °C for many Arctic species. Consequently, the magnitude of temperature increase is a crucial factor for microbial community reorganization and the ensuing ecological consequences in the future Arctic Ocean.
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9
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Arandia-Gorostidi N, Parada AE, Dekas AE. Single-cell view of deep-sea microbial activity and intracommunity heterogeneity. THE ISME JOURNAL 2023; 17:59-69. [PMID: 36202927 PMCID: PMC9750969 DOI: 10.1038/s41396-022-01324-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 09/08/2022] [Accepted: 09/12/2022] [Indexed: 12/15/2022]
Abstract
Microbial activity in the deep sea is cumulatively important for global elemental cycling yet is difficult to quantify and characterize due to low cell density and slow growth. Here, we investigated microbial activity off the California coast, 50-4000 m water depth, using sensitive single-cell measurements of stable-isotope uptake and nucleic acid sequencing. We observed the highest yet reported proportion of active cells in the bathypelagic (up to 78%) and calculated that deep-sea cells (200-4000 m) are responsible for up to 34% of total microbial biomass synthesis in the water column. More cells assimilated nitrogen derived from amino acids than ammonium, and at higher rates. Nitrogen was assimilated preferentially to carbon from amino acids in surface waters, while the reverse was true at depth. We introduce and apply the Gini coefficient, an established equality metric in economics, to quantify intracommunity heterogeneity in microbial anabolic activity. We found that heterogeneity increased with water depth, suggesting a minority of cells contribute disproportionately to total activity in the deep sea. This observation was supported by higher RNA/DNA ratios for low abundance taxa at depth. Intracommunity activity heterogeneity is a fundamental and rarely measured ecosystem parameter and may have implications for community function and resilience.
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Affiliation(s)
| | - A E Parada
- Department of Earth System Science, Stanford University, Stanford, CA, USA
| | - A E Dekas
- Department of Earth System Science, Stanford University, Stanford, CA, USA.
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10
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Frequent Occurrence and Metabolic Versatility of Marinifilaceae Bacteria as Key Players in Organic Matter Mineralization in Global Deep Seas. mSystems 2022; 7:e0086422. [PMID: 36342154 PMCID: PMC9765461 DOI: 10.1128/msystems.00864-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Transfer of animal and plant detritus of both terrestrial and marine origins to the deep sea occurs on a global scale. Microorganisms play an important role in mineralizing them therein, but these are yet to be identified in situ. To observe key bacteria involved, we conducted long-term in situ incubation and found that members of the family Marinifilaceae (MF) occurred as some of the most predominant bacteria thriving on the new inputs of plant and animal biomasses in the deep sea in both marginal and oceanic areas. This taxon is diverse and ubiquitous in marine environments. A total of 11 MAGs belonging to MF were retrieved from metagenomic data and diverged into four subgroups in the phylogenomic tree. Based on metagenomic and metatranscriptomic analyses, we described the metabolic features and in situ metabolizing activities of different subgroups. The MF-2 subgroup, which dominates plant detritus-enriched cultures, specializes in polysaccharide degradation and lignin oxidation and has high transcriptional activities of related genes in situ. Intriguingly, members of this subgroup encode a nitrogen fixation pathway to compensate for the shortage of nitrogen sources inside the plant detritus. In contrast, other subgroups dominating the animal tissue-supported microbiomes are distinguished from MF-2 with regard to carbon and nitrogen metabolism and exhibit high transcriptional activity for proteolysis in situ. Despite these metabolic divergences of MF lineages, they show high in situ transcriptional activities for organic fermentation and anaerobic respiration (reductions of metal and/or dimethyl sulfoxide). These results highlight the role of previously unrecognized Marinifilaceae bacteria in organic matter mineralization in marine environments by coupling carbon and nitrogen cycling with metal and sulfur. IMPORTANCE Microbial mineralization of organic matter has a significant impact on the global biogeochemical cycle. This report confirms the role of Marinifilaceae in organic degradation in the oceans, with a contribution to ocean carbon cycling that has previously been underestimated. It was the dominant taxon thriving on plant and animal biomasses in our in situ incubator, as well as in whale falls and wood falls. At least 9 subgroups were revealed, and they were widely distributed in oceans globally but predominant in organic-matter-rich environments, with an average relative abundance of 8.3%. Different subgroups display a preference for the degradation of different macromolecules (polysaccharides, lignin, and protein) and adapt to their environments via special metabolic mechanisms.
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Benavides M, Bonnet S, Le Moigne FAC, Armin G, Inomura K, Hallstrøm S, Riemann L, Berman-Frank I, Poletti E, Garel M, Grosso O, Leblanc K, Guigue C, Tedetti M, Dupouy C. Sinking Trichodesmium fixes nitrogen in the dark ocean. THE ISME JOURNAL 2022; 16:2398-2405. [PMID: 35835942 PMCID: PMC9478103 DOI: 10.1038/s41396-022-01289-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 06/29/2022] [Accepted: 07/05/2022] [Indexed: 01/04/2023]
Abstract
The photosynthetic cyanobacterium Trichodesmium is widely distributed in the surface low latitude ocean where it contributes significantly to N2 fixation and primary productivity. Previous studies found nifH genes and intact Trichodesmium colonies in the sunlight-deprived meso- and bathypelagic layers of the ocean (200-4000 m depth). Yet, the ability of Trichodesmium to fix N2 in the dark ocean has not been explored. We performed 15N2 incubations in sediment traps at 170, 270 and 1000 m at two locations in the South Pacific. Sinking Trichodesmium colonies fixed N2 at similar rates than previously observed in the surface ocean (36-214 fmol N cell-1 d-1). This activity accounted for 40 ± 28% of the bulk N2 fixation rates measured in the traps, indicating that other diazotrophs were also active in the mesopelagic zone. Accordingly, cDNA nifH amplicon sequencing revealed that while Trichodesmium accounted for most of the expressed nifH genes in the traps, other diazotrophs such as Chlorobium and Deltaproteobacteria were also active. Laboratory experiments simulating mesopelagic conditions confirmed that increasing hydrostatic pressure and decreasing temperature reduced but did not completely inhibit N2 fixation in Trichodesmium. Finally, using a cell metabolism model we predict that Trichodesmium uses photosynthesis-derived stored carbon to sustain N2 fixation while sinking into the mesopelagic. We conclude that sinking Trichodesmium provides ammonium, dissolved organic matter and biomass to mesopelagic prokaryotes.
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Affiliation(s)
- Mar Benavides
- Aix Marseille Univ, Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France.
- Turing Center for Living Systems, Aix-Marseille University, 13009, Marseille, France.
| | - Sophie Bonnet
- Aix Marseille Univ, Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
| | - Frédéric A C Le Moigne
- Aix Marseille Univ, Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
- LEMAR, Laboratoire des Sciences de l'Environnement Marin, UMR6539, CNRS, UBO, IFREMER, IRD, 29280, Plouzané, Technopôle Brest-Iroise, France
| | - Gabrielle Armin
- Graduate School of Oceanography, University of Rhode Island, South Kingstown, RI, USA
| | - Keisuke Inomura
- Graduate School of Oceanography, University of Rhode Island, South Kingstown, RI, USA
| | - Søren Hallstrøm
- Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark
| | - Lasse Riemann
- Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark
| | - Ilana Berman-Frank
- Department of Marine Biology, Leon H. Charney School of Marine Sciences, University of Haifa, Mt, Carmel, Haifa, Israel
| | - Emilie Poletti
- Aix Marseille Univ, Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
| | - Marc Garel
- Aix Marseille Univ, Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
| | - Olivier Grosso
- Aix Marseille Univ, Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
| | - Karine Leblanc
- Aix Marseille Univ, Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
| | - Catherine Guigue
- Aix Marseille Univ, Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
| | - Marc Tedetti
- Aix Marseille Univ, Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
| | - Cécile Dupouy
- Aix Marseille Univ, Université de Toulon, CNRS, IRD, MIO UM 110, 13288, Marseille, France
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Lloyd CC, Brown S, Balmonte JP, Hoarfrost A, Ghobrial S, Arnosti C. Particles act as ‘specialty centers’ with expanded enzymatic function throughout the water column in the western North Atlantic. Front Microbiol 2022; 13:882333. [PMID: 36246226 PMCID: PMC9553992 DOI: 10.3389/fmicb.2022.882333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 09/12/2022] [Indexed: 11/13/2022] Open
Abstract
Heterotrophic bacteria initiate the degradation of high molecular weight organic matter by producing an array of extracellular enzymes to hydrolyze complex organic matter into sizes that can be taken up into the cell. These bacterial communities differ spatially and temporally in composition, and potentially also in their enzymatic complements. Previous research has shown that particle-associated bacteria can be considerably more active than bacteria in the surrounding bulk water, but most prior studies of particle-associated bacteria have been focused on the upper ocean - there are few measurements of enzymatic activities of particle-associated bacteria in the mesopelagic and bathypelagic ocean, although the bacterial communities in the deep are dependent upon degradation of particulate organic matter to fuel their metabolism. We used a broad suite of substrates to compare the glucosidase, peptidase, and polysaccharide hydrolase activities of particle-associated and unfiltered seawater microbial communities in epipelagic, mesopelagic, and bathypelagic waters across 11 stations in the western North Atlantic. We concurrently determined bacterial community composition of unfiltered seawater and of samples collected via gravity filtration (>3 μm). Overall, particle-associated bacterial communities showed a broader spectrum of enzyme activities compared with unfiltered seawater communities. These differences in enzymatic activities were greater at offshore than at coastal locations, and increased with increasing depth in the ocean. The greater differences in enzymatic function measured on particles with depth coincided with increasing differences in particle-associated community composition, suggesting that particles act as ‘specialty centers’ that are essential for degradation of organic matter even at bathypelagic depths.
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Affiliation(s)
- C. Chad Lloyd
- Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- *Correspondence: C. Chad Lloyd,
| | - Sarah Brown
- Environment, Ecology and Energy Program, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - John Paul Balmonte
- Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Department of Biology, HADAL and Nordcee, University of Southern Denmark, Odense, Denmark
| | - Adrienne Hoarfrost
- Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Department of Marine Sciences, University of Georgia, Athens, GA, United States
| | - Sherif Ghobrial
- Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Carol Arnosti
- Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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Broman E, Izabel-Shen D, Rodríguez-Gijón A, Bonaglia S, Garcia SL, Nascimento FJA. Microbial functional genes are driven by gradients in sediment stoichiometry, oxygen, and salinity across the Baltic benthic ecosystem. MICROBIOME 2022; 10:126. [PMID: 35965333 PMCID: PMC9377124 DOI: 10.1186/s40168-022-01321-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 07/05/2022] [Indexed: 05/30/2023]
Abstract
BACKGROUND Microorganisms in the seafloor use a wide range of metabolic processes, which are coupled to the presence of functional genes within their genomes. Aquatic environments are heterogenous and often characterized by natural physiochemical gradients that structure these microbial communities potentially changing the diversity of functional genes and its associated metabolic processes. In this study, we investigated spatial variability and how environmental variables structure the diversity and composition of benthic functional genes and metabolic pathways across various fundamental environmental gradients. We analyzed metagenomic data from sediment samples, measured related abiotic data (e.g., salinity, oxygen and carbon content), covering 59 stations spanning 1,145 km across the Baltic Sea. RESULTS The composition of genes and microbial communities were mainly structured by salinity plus oxygen, and the carbon to nitrogen (C:N) ratio for specific metabolic pathways related to nutrient transport and carbon metabolism. Multivariate analyses indicated that the compositional change in functional genes was more prominent across environmental gradients compared to changes in microbial taxonomy even at genus level, and indicate functional diversity adaptation to local environments. Oxygen deficient areas (i.e., dead zones) were more different in gene composition when compared to oxic sediments. CONCLUSIONS This study highlights how benthic functional genes are structured over spatial distances and by environmental gradients and resource availability, and suggests that changes in, e.g., oxygenation, salinity, and carbon plus nitrogen content will influence functional metabolic pathways in benthic habitats. Video Abstract.
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Affiliation(s)
- Elias Broman
- Department of Ecology, Environment and Plant Sciences, Stockholm University, 106 91 Stockholm, Sweden
- Baltic Sea Centre, Stockholm University, Stockholm, Sweden
| | - Dandan Izabel-Shen
- Department of Ecology, Environment and Plant Sciences, Stockholm University, 106 91 Stockholm, Sweden
| | - Alejandro Rodríguez-Gijón
- Department of Ecology, Environment and Plant Sciences, Stockholm University, 106 91 Stockholm, Sweden
- Science for Life Laboratory, Stockholm, Sweden
| | - Stefano Bonaglia
- Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Sarahi L. Garcia
- Department of Ecology, Environment and Plant Sciences, Stockholm University, 106 91 Stockholm, Sweden
- Science for Life Laboratory, Stockholm, Sweden
| | - Francisco J. A. Nascimento
- Department of Ecology, Environment and Plant Sciences, Stockholm University, 106 91 Stockholm, Sweden
- Baltic Sea Centre, Stockholm University, Stockholm, Sweden
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14
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Tracing the path of carbon export in the ocean though DNA sequencing of individual sinking particles. THE ISME JOURNAL 2022; 16:1896-1906. [PMID: 35444263 PMCID: PMC9296562 DOI: 10.1038/s41396-022-01239-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 03/31/2022] [Accepted: 04/05/2022] [Indexed: 01/04/2023]
Abstract
Surface phytoplankton communities were linked with the carbon they export into the deep ocean by comparing 18 S rRNA gene sequence communities from surface seawater and individually isolated sinking particles. Particles were collected in sediment traps deployed at locations in the North Pacific subtropical gyre and the California Current. DNA was isolated from individual particles, bulk-collected trap particles, and the surface seawater. The relative sequence abundance of exported phytoplankton taxa in the surface water varied across functional groups and ecosystems. Of the sequences detected in sinking particles, about half were present in large (>300 μm), individually isolated particles and primarily belonged to taxa with small cell sizes (<50 µm). Exported phytoplankton taxa detected only in bulk trap samples, and thus presumably packaged in the smaller sinking size fraction, contained taxa that typically have large cell sizes (>500 μm). The effect of particle degradation on the detectable 18 S rRNA gene community differed across taxa, and differences in community composition among individual particles from the same location largely reflected differences in relative degradation state. Using these data and particle imaging, we present an approach that incorporates genetic diversity into mechanistic models of the ocean’s biological carbon pump, which will lead to better quantification of the ocean’s carbon cycle.
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15
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Metabolic Phenotyping of Marine Heterotrophs on Refactored Media Reveals Diverse Metabolic Adaptations and Lifestyle Strategies. mSystems 2022; 7:e0007022. [PMID: 35856685 PMCID: PMC9426600 DOI: 10.1128/msystems.00070-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microbial communities, through their metabolism, drive carbon cycling in marine environments. These complex communities are composed of many different microorganisms including heterotrophic bacteria, each with its own nutritional needs and metabolic capabilities. Yet, models of ecosystem processes typically treat heterotrophic bacteria as a “black box,” which does not resolve metabolic heterogeneity nor address ecologically important processes such as the successive modification of different types of organic matter. Here we directly address the heterogeneity of metabolism by characterizing the carbon source utilization preferences of 63 heterotrophic bacteria representative of several major marine clades. By systematically growing these bacteria on 10 media containing specific subsets of carbon sources found in marine biomass, we obtained a phenotypic fingerprint that we used to explore the relationship between metabolic preferences and phylogenetic or genomic features. At the class level, these bacteria display broadly conserved patterns of preference for different carbon sources. Despite these broad taxonomic trends, growth profiles correlate poorly with phylogenetic distance or genome-wide gene content. However, metabolic preferences are strongly predicted by a handful of key enzymes that preferentially belong to a few enriched metabolic pathways, such as those involved in glyoxylate metabolism and biofilm formation. We find that enriched pathways point to enzymes directly involved in the metabolism of the corresponding carbon source and suggest potential associations between metabolic preferences and other ecologically relevant traits. The availability of systematic phenotypes across multiple synthetic media constitutes a valuable resource for future quantitative modeling efforts and systematic studies of interspecies interactions. IMPORTANCE Half of the Earth’s annual primary production is carried out by phytoplankton in the surface ocean. However, this metabolic activity is heavily impacted by heterotrophic bacteria, which dominate the transformation of organic matter released from phytoplankton. Here, we characterize the diversity of metabolic preferences across many representative heterotrophs by systematically growing them on different fractions of dissolved organic carbon. Our analysis suggests that different clades of bacteria have substantially distinct preferences for specific carbon sources, in a way that cannot be simply mapped onto phylogeny. These preferences are associated with the presence of specific genes and pathways, reflecting an association between metabolic capabilities and ecological lifestyles. In addition to helping understand the importance of heterotrophs under different conditions, the phenotypic fingerprint we obtained can help build higher resolution quantitative models of global microbial activity and biogeochemical cycles in the oceans.
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16
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Diverse Genomic Traits Differentiate Sinking-Particle-Associated versus Free-Living Microbes throughout the Oligotrophic Open Ocean Water Column. mBio 2022; 13:e0156922. [PMID: 35862780 PMCID: PMC9426571 DOI: 10.1128/mbio.01569-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Bacteria and archaea are central to the production, consumption, and remineralization of dissolved and particulate organic matter and contribute critically to carbon delivery, nutrient availability, and energy transformations in the deep ocean. To explore environmentally relevant genomic traits of sinking-particle-associated versus free-living microbes, we compared habitat-specific metagenome-assembled genomes recovered throughout the water column in the North Pacific Subtropical Gyre. The genomic traits of sinking-particle-associated versus free-living prokaryotes were compositionally, functionally, and phylogenetically distinct. Substrate-specific transporters and extracellular peptidases and carbohydrate-active enzymes were more enriched and diverse in particle-associated microbes at all depths than in free-living counterparts. These data indicate specific roles for particle-attached microbes in particle substrate hydrolysis, uptake, and remineralization. Shallow-water particle-associated microbes had elevated genomic GC content and proteome nitrogen content and reduced proteome carbon content in comparison to abyssal particle-associated microbes. An inverse trend was observed for their sympatric free-living counterparts. These different properties of attached microbes are postulated to arise in part due to elevated organic and inorganic nitrogen availability inside sinking particles. Particle-attached microbes also were enriched in genes for environmental sensing via two-component regulatory systems, and cell-cell interactions via extracellular secretion systems, reflecting their surface-adapted lifestyles. Finally, particle-attached bacteria had greater predicted maximal growth efficiencies than free-living bacterioplankton at all depths. All of these particle-associated specific genomic and proteomic features appear to be driven by microhabitat-specific elevated nutrient and energy availability as well as surface-associated competitive and synergistic ecological interactions. Although some of these characteristics have been previously postulated or observed individually, we report them together here in aggregate via direct comparisons of cooccurring free-living and sinking-particle-attached microbial genomes from the open ocean.
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17
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Ma X, Johnson KB, Gu B, Zhang H, Li G, Huang X, Xia X. The in-situ release of algal bloom populations and the role of prokaryotic communities in their establishment and growth. WATER RESEARCH 2022; 219:118565. [PMID: 35597219 DOI: 10.1016/j.watres.2022.118565] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 05/03/2022] [Accepted: 05/05/2022] [Indexed: 06/15/2023]
Abstract
Harmful algal blooms (HABs) may quickly travel and inoculate new water bodies via currents and runoff in estuaries. The role of in-situ prokaryotic communities in the re-establishment and growth of inoculated algal blooms remains unknown. A novel on-board incubation experiment was employed to simulate the sudden surge of algal blooms to new estuarine waters and reveal possible outcomes. A dinoflagellate (Amphidinium carterae) and a diatom species (Thalassiosira weissflogii) which had bloomed in the Pearl River Estuary (PRE) area were cultured to bloom densities and reintroduced back into PRE natural seawaters. The diatom showed better adaptation ability to the new environment and increased significantly after the incubation. Simultaneously, particle-attached (PA) prokaryotic community structure was strongly influenced by adding of the diatom, with some opportunistic prokaryotes significantly enhanced in the diatom treatment. Whereas the dinoflagellate population did not increase following incubation, and their PA prokaryotic community showed no significant differences relative to the control. Metagenomic analyzes revealed that labile carbohydrates and organic nitrogen produced by the diatom contributed to the surge of certain PA prokaryotes. Genomic properties of a bacteria strain, which is affiliated with genus GMD16E07 (Planctomycetaceae) and comprised up to 50% of PA prokaryotes in the diatom treatment, was described here for the first time. Notably, the association of Planctomycetaceae and T. weissflogii likely represents symbiotic mutualism, with the diatom providing organic matter for Planctomycetaceae and the bacteria supplying vitamins and detoxifying nitriles and hydrogen peroxides in exchange. Therefore, the close association between Planctomycetaceae and T. weissflogii promoted the growth of both populations, and eventually facilitated the diatom bloom establishment.
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Affiliation(s)
- Xiao Ma
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China
| | - Kevin B Johnson
- Department of Ocean Engineering and Marine Sciences, Florida Institute of Technology, Melbourne, FL, United States
| | - Bowei Gu
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; University of Chinese Academy of Sciences, Beijing, China
| | - Hao Zhang
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China
| | - Gang Li
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China
| | - Xiaoping Huang
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China
| | - Xiaomin Xia
- Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China.
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18
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Luo E, Leu AO, Eppley JM, Karl DM, DeLong EF. Diversity and origins of bacterial and archaeal viruses on sinking particles reaching the abyssal ocean. THE ISME JOURNAL 2022; 16:1627-1635. [PMID: 35236926 PMCID: PMC9122931 DOI: 10.1038/s41396-022-01202-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 01/09/2022] [Accepted: 01/25/2022] [Indexed: 11/15/2022]
Abstract
Sinking particles and particle-associated microbes influence global biogeochemistry through particulate matter export from the surface to the deep ocean. Despite ongoing studies of particle-associated microbes, viruses in these habitats remain largely unexplored. Whether, where, and which viruses might contribute to particle production and export remain open to investigation. In this study, we analyzed 857 virus population genomes associated with sinking particles collected over three years in sediment traps moored at 4000 m in the North Pacific Subtropical Gyre. Particle-associated viruses here were linked to cellular hosts through matches to bacterial and archaeal metagenome-assembled genome (MAG)-encoded prophages or CRISPR spacers, identifying novel viruses infecting presumptive deep-sea bacteria such as Colwellia, Moritella, and Shewanella. We also identified lytic viruses whose abundances correlated with particulate carbon flux and/or were exported from the photic to abyssal ocean, including cyanophages. Our data are consistent with some of the predicted outcomes of the viral shuttle hypothesis, and further suggest that viral lysis of both autotrophic and heterotrophic prokaryotes may play a role in carbon export. Our analyses revealed the diversity and origins of prevalent viruses found on deep-sea sinking particles and identified prospective viral groups for future investigation into processes that govern particle export in the open ocean.
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Affiliation(s)
- Elaine Luo
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education (C-MORE), University of Hawai'i at Manoa, Honolulu, HI, 96822, USA.
- Woods Hole Oceanographic Institution, 266 Woods Hole Road, MS 51, Woods Hole MA, 02543, Falmouth, USA.
| | - Andy O Leu
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education (C-MORE), University of Hawai'i at Manoa, Honolulu, HI, 96822, USA
- Australia Center for Ecogenomics, University of Queensland, St. Lucia QLD, 4072, Australia
| | - John M Eppley
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education (C-MORE), University of Hawai'i at Manoa, Honolulu, HI, 96822, USA
| | - David M Karl
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education (C-MORE), University of Hawai'i at Manoa, Honolulu, HI, 96822, USA
| | - Edward F DeLong
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education (C-MORE), University of Hawai'i at Manoa, Honolulu, HI, 96822, USA.
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Qu L, Cai R, Hu Z, Wang H. Metagenomic assemblage genomes analyses reveal the polysaccharides hydrolyzing potential of marine group II euryarchaea. ENVIRONMENTAL RESEARCH 2022; 209:112865. [PMID: 35120891 DOI: 10.1016/j.envres.2022.112865] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 01/02/2022] [Accepted: 01/27/2022] [Indexed: 06/14/2023]
Abstract
Marine group II euryarchaea (MGII) dominates the planktonic archaeal community in global surface seawater and is associated to particulate organic matters mainly composed of polysaccharides. However, the polysaccharides metabolism of MGII euryarchaea is unclear. In this study, the distribution and polysaccharides metabolism potential of MGII euryarchaea in the estuary were investigated. High-throughput sequencing of 16S rRNA genes showed that MGII euryarchaea was the predominant archaeal group in the Pearl River Estuary (PRE), and the relative abundance of MGII euryarchaea in particle-attached fraction was higher than that in free-living fractions. A total of 19 metagenome-assembled genomes (MAGs) were successfully reconstructed from metagenomic data, of which 10 MAGs were grouped as MGII euryarchaea according to phylogenomic analysis. Genes encoding a variety of carbohydrate-active enzymes (CAZymes) were found in MAGs/genomes of MGII euryarchaea. These CAZymes annotated in MAGs were capable of hydrolyzing many polysaccharides, including α-glucans, β-glucans, xylans, nitrogen-containing polysaccharides, and some insoluble galactans. The results also indicated that MGII euryarchaea has some unique enzymes that can hydrolyze starch, β-1,3-glucans, complex xylans, carrageenan, and agarose. Collectively, our results demonstrated that MGII euryarchaea has great polysaccharides hydrolysis potential and could play an important role in the carbon cycle of marine ecosystem.
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Affiliation(s)
- Liping Qu
- Biology Department and Institute of Marine Sciences, College of Science, Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, 515063, China
| | - Runlin Cai
- Biology Department and Institute of Marine Sciences, College of Science, Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, 515063, China
| | - Zhong Hu
- Biology Department and Institute of Marine Sciences, College of Science, Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, 515063, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, China
| | - Hui Wang
- Biology Department and Institute of Marine Sciences, College of Science, Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, 515063, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, China.
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Maturana-Martínez C, Iriarte JL, Ha SY, Lee B, Ahn IY, Vernet M, Cape M, Fernández C, González HE, Galand PE. Biogeography of Southern Ocean Active Prokaryotic Communities Over a Large Spatial Scale. Front Microbiol 2022; 13:862812. [PMID: 35592001 PMCID: PMC9111744 DOI: 10.3389/fmicb.2022.862812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 03/18/2022] [Indexed: 12/04/2022] Open
Abstract
The activity of marine microorganisms depends on community composition, yet, in some oceans, less is known about the environmental and ecological processes that structure their distribution. The objective of this study was to test the effect of geographical distance and environmental parameters on prokaryotic community structure in the Southern Ocean (SO). We described the total (16S rRNA gene) and the active fraction (16S rRNA-based) of surface microbial communities over a ~6,500 km longitudinal transect in the SO. We found that the community composition of the total fraction was different from the active fraction across the zones investigated. In addition, higher α-diversity and stronger species turnover were displayed in the active community compared to the total community. Oceanospirillales, Alteromonadales, Rhodobacterales, and Flavobacteriales dominated the composition of the bacterioplankton communities; however, there were marked differences at the order level. Temperature, salinity, silicic acid, particulate organic nitrogen, and particulate organic carbon correlated with the composition of bacterioplankton communities. A strong distance–decay pattern between closer and distant communities was observed. We hypothesize that it was related to the different oceanic fronts present in the Antarctic Circumpolar Current. Our findings contribute to a better understanding of the complex arrangement that shapes the structure of bacterioplankton communities in the SO.
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Affiliation(s)
- Claudia Maturana-Martínez
- Centro de Investigación Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL) and Universidad Austral de Chile, Valdivia, Chile.,Sorbonne Université, CNRS, Laboratoire d'Ecogéochimie des Environnements Benthiques, Banyuls-sur-Mer, France
| | - José Luis Iriarte
- Centro de Investigación Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL) and Universidad Austral de Chile, Valdivia, Chile
| | - Sun-Yong Ha
- Division of Polar Ocean Science, Korea Polar Research Institute, Incheon, South Korea
| | - Boyeon Lee
- Division of Polar Ocean Science, Korea Polar Research Institute, Incheon, South Korea
| | - In-Young Ahn
- Division of Polar Ocean Science, Korea Polar Research Institute, Incheon, South Korea
| | - Maria Vernet
- Scripps Institution of Oceanography, University of California, San Diego, San Diego, CA, United States
| | - Mattias Cape
- School of Oceanography, University of Washington, Seattle, WA, United States
| | - Camila Fernández
- Sorbonne Université, CNRS, Laboratoire d'Océanographie Microbienne (LOMIC), Banyuls-sur-Mer, France
| | - Humberto E González
- Centro de Investigación Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL) and Universidad Austral de Chile, Valdivia, Chile
| | - Pierre E Galand
- Sorbonne Université, CNRS, Laboratoire d'Ecogéochimie des Environnements Benthiques, Banyuls-sur-Mer, France
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21
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Jiang C, Zhu S, Feng J, Shui W. Slope aspect affects the soil microbial communities in karst tiankeng negative landforms. BMC Ecol Evol 2022; 22:54. [PMID: 35501694 PMCID: PMC9063220 DOI: 10.1186/s12862-022-01986-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 03/04/2022] [Indexed: 01/10/2023] Open
Abstract
Background Karst tiankeng is a large-scale negative surface terrain, and slope aspects affect the soil conditions, vegetation and microbial flora in the tiankeng. However, the influence of the slope aspect on the soil microbial community in tiankeng has not been elucidated. Methods In this study, metagenomic sequencing technology was used to analyze the soil microbial community structure and functional potentials on the shady and sunny slopes of karst tiankeng. Results The Shannon–Wiener diversity of microbial communities on shady slope (SHS) was significantly higher than that on sunny slope (SUS). Although the composition of dominant phyla on shady slope (SHS) and sunny slope (SUS) was similar, there were significant differences in beta-diversity. The linear discriminate analysis (LDA) results showed that biomarkers mainly belongs to Actinobacteria, Chloroflexi and Proteobacteria. Functional pathways and CAZy (Carbohydrate-Active Enzymes) genes also had a remarkable response to slope aspect change. LEfSe results indicated several biomarker pathways in sunny slope involved in human disease. Moreover, the abundance of CAZy genes was higher in shady slope and had stronger ability in decomposing litter. The microbial communities were mainly correlation with the vegetation characteristics (species richness and coverage) and soil properties (SOC and pH). Conclusions These results indicate slope aspect has a pronounced influence on microbial community composition, structure and function at karst tiankeng. In the future, the conservation of karst tiankeng biodiversity should pay more attention to topographical factors. Supplementary Information The online version contains supplementary material available at 10.1186/s12862-022-01986-y.
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22
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Jiang C, Sun XR, Feng J, Zhu SF, Shui W. Metagenomic analysis reveals the different characteristics of microbial communities inside and outside the karst tiankeng. BMC Microbiol 2022; 22:115. [PMID: 35473500 PMCID: PMC9040234 DOI: 10.1186/s12866-022-02513-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 03/28/2022] [Indexed: 01/10/2023] Open
Abstract
Background Karst tiankengs serve as a reservoir of biodiversity in the degraded karst landscape areas. However, the microbial diversity of karst tiankengs is poorly understood. Here, we investigated the composition and function of the microbial community in a karst tiankeng. Results We found that habitat differences inside and outside the karst tiankeng changed the composition and structure of the soil microbial communities, and the dominant phyla were Proteobacteria, Actinobacteria, Chloroflexi and Acidobacteria. The Shannon–Wiener diversity of microbial communities inside and outside the tiankeng was significantly different, and it was higher inside the tiankeng (IT). Venn and LEfSe analysis found that the soil microbial communities inside the tiankeng had 640 more endemic species and 39 more biomarker microbial clades than those identified outside of the tiankeng (OT)..Functional prediction indicated that soil microorganisms in outside the tiankeng had a high potential for carbohydrate metabolism, translation and amino acid metabolism. There were biomarker pathways associated with several of human diseases at both IT and OT sites. Except for auxiliary activities (AA), other CAZy classes had higher abundance at IT sites, which can readily convert litter and fix carbon and nitrogen, thereby supporting the development of underground forests. The differences in microbial communities were mainly related to the soil water content and soil total nitrogen. Conclusions Our results provide a metagenomic overview of the karst tiankeng system and provide new insights into habitat conservation and biodiversity restoration in the area. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-022-02513-1.
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Affiliation(s)
- Cong Jiang
- College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Xiao-Rui Sun
- College of Environment Safety Engineering, Fuzhou University, Fuzhou, 350116, China
| | - Jie Feng
- College of Environment Safety Engineering, Fuzhou University, Fuzhou, 350116, China
| | - Su-Feng Zhu
- Chinese Research Academy of Environmental Sciences, Beijing, 100020, China
| | - Wei Shui
- College of Environment Safety Engineering, Fuzhou University, Fuzhou, 350116, China.
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23
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Abstract
Exocellular DNA is operationally defined as the fraction of the total DNA pool that passes through a membrane filter (0.1 μm). It is composed of DNA-containing vesicles, viruses, and free DNA and is ubiquitous in all aquatic systems, although the sources, sinks, and ecological consequences are largely unknown. Using a method that provides separation of these three fractions, we compared open ocean depth profiles of DNA associated with each fraction. Pelagibacter-like DNA dominated the vesicle fractions for all samples examined over a depth range of 75 to 500 m. Viral DNA consisted predominantly of myovirus-like and podovirus-like DNA and contained the highest proportion of unannotated sequences. Euphotic zone free DNA (75 to 125 m) contained primarily bacterial and viral sequences, with bacteria dominating samples from the mesopelagic zone (500 to 1,000 m). A high proportion of mesopelagic zone free DNA sequences appeared to originate from surface waters, including a large amount of DNA contributed by high-light Prochlorococcus ecotypes. Throughout the water column, but especially in the mesopelagic zone, the composition of free DNA sequences was not always reflective of cooccurring microbial communities that inhabit the same sampling depth. These results reveal the composition of free DNA in different regions of the water column (euphotic and mesopelagic zones), with implications for dissolved organic matter cycling and export (by way of sinking particles and/or migratory zooplankton) as a delivery mechanism. IMPORTANCE With advances in metagenomic sequencing, the microbial composition of diverse environmental systems has been investigated, providing new perspectives on potential ecological dynamics and dimensions for experimental investigations. Here, we characterized exocellular free DNA via metagenomics, using a newly developed method that separates free DNA from cells, viruses, and vesicles, and facilitated the independent characterization of each fraction. The fate of this free DNA has both ecological consequences as a nutrient (N and P) source and potential evolutionary consequences as a source of genetic transformation. Here, we document different microbial sources of free DNA at the surface (0 to 200 m) versus depths of 250 to 1,000 m, suggesting that distinct free DNA production mechanisms may be present throughout the oligotrophic water column. Examining microbial processes through the lens of exocellular DNA provides insights into the production of labile dissolved organic matter (i.e., free DNA) at the surface (likely by viral lysis) and processes that influence the fate of sinking, surface-derived organic matter.
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24
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Sanz-Sáez I, Pereira-García C, Bravo AG, Trujillo L, Pla i Ferriol M, Capilla M, Sánchez P, Rodríguez Martín-Doimeadios RC, Acinas SG, Sánchez O. Prevalence of Heterotrophic Methylmercury Detoxifying Bacteria across Oceanic Regions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:3452-3461. [PMID: 35245029 PMCID: PMC8928480 DOI: 10.1021/acs.est.1c05635] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 01/29/2022] [Accepted: 01/31/2022] [Indexed: 05/27/2023]
Abstract
Microbial reduction of inorganic divalent mercury (Hg2+) and methylmercury (MeHg) demethylation is performed by the mer operon, specifically by merA and merB genes, respectively, but little is known about the mercury tolerance capacity of marine microorganisms and its prevalence in the ocean. Here, combining culture-dependent analyses with metagenomic and metatranscriptomic data, we show that marine bacteria that encode mer genes are widespread and active in the global ocean. We explored the distribution of these genes in 290 marine heterotrophic bacteria (Alteromonas and Marinobacter spp.) isolated from different oceanographic regions and depths, and assessed their tolerance to diverse concentrations of Hg2+ and MeHg. In particular, the Alteromonas sp. ISS312 strain presented the highest tolerance capacity and a degradation efficiency for MeHg of 98.2% in 24 h. Fragment recruitment analyses of Alteromonas sp. genomes (ISS312 strain and its associated reconstructed metagenome assembled genome MAG-0289) against microbial bathypelagic metagenomes confirm their prevalence in the deep ocean. Moreover, we retrieved 54 merA and 6 merB genes variants related to the Alteromonas sp. ISS312 strain from global metagenomes and metatranscriptomes from Tara Oceans. Our findings highlight the biological reductive MeHg degradation as a relevant pathway of the ocean Hg biogeochemical cycle.
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Affiliation(s)
- Isabel Sanz-Sáez
- Departament
de Biologia Marina i Oceanografia, Institut
de Ciències del Mar, ICM-CSIC, 08003 Barcelona, Catalunya, Spain
| | - Carla Pereira-García
- Departament
de Biologia Marina i Oceanografia, Institut
de Ciències del Mar, ICM-CSIC, 08003 Barcelona, Catalunya, Spain
| | - Andrea G. Bravo
- Departament
de Biologia Marina i Oceanografia, Institut
de Ciències del Mar, ICM-CSIC, 08003 Barcelona, Catalunya, Spain
| | - Laura Trujillo
- Departament
de Biologia Marina i Oceanografia, Institut
de Ciències del Mar, ICM-CSIC, 08003 Barcelona, Catalunya, Spain
| | - Martí Pla i Ferriol
- Departament
de Genètica i Microbiologia, Facultat de Biociències, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Miguel Capilla
- Research
Group in Environmental Engineering (GI2AM), Department of Chemical
Engineering, University of Valencia, Av. De la Universitat S/N, 46100 Burjassot, Spain
| | - Pablo Sánchez
- Departament
de Biologia Marina i Oceanografia, Institut
de Ciències del Mar, ICM-CSIC, 08003 Barcelona, Catalunya, Spain
| | - Rosa Carmen Rodríguez Martín-Doimeadios
- Environmental
Sciences Institute (ICAM), Department of Analytical Chemistry and
Food Technology, University of Castilla-La
Mancha, Avda. Carlos
III s/n, 45071 Toledo, Spain
| | - Silvia G. Acinas
- Departament
de Biologia Marina i Oceanografia, Institut
de Ciències del Mar, ICM-CSIC, 08003 Barcelona, Catalunya, Spain
| | - Olga Sánchez
- Departament
de Genètica i Microbiologia, Facultat de Biociències, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
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25
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Diversity Distribution, Driving Factors and Assembly Mechanisms of Free-Living and Particle-Associated Bacterial Communities at a Subtropical Marginal Sea. Microorganisms 2021; 9:microorganisms9122445. [PMID: 34946047 PMCID: PMC8704526 DOI: 10.3390/microorganisms9122445] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/21/2021] [Accepted: 11/24/2021] [Indexed: 01/04/2023] Open
Abstract
Free-living (FL) and particle-associated (PA) bacterioplankton communities play critical roles in biogeochemical cycles in the ocean. However, their community composition, assembly process and functions in the continental shelf and slope regions are poorly understood. Based on 16S rRNA gene amplicon sequencing, we investigated bacterial communities’ driving factors, assembly processes and functional potentials at a subtropical marginal sea. The bacterioplankton community showed specific distribution patterns with respect to lifestyle (free living vs. particle associated), habitat (slope vs. shelf) and depth (surface vs. DCM and Bottom). Salinity and water temperature were the key factors modulating turnover in the FL community, whereas nitrite, silicate and phosphate were the key factors for the PA community. Model analyses revealed that stochastic processes outweighed deterministic processes and had stronger influences on PA than FL. Homogeneous selection (Hos) was more responsible for the assembly and turnover of FL, while drift and dispersal limitation contributed more to the assembly of PA. Importantly, the primary contributor to Hos in PA was Gammaproteobacteria:Others, whereas that in FL was Cyanobacteria:Bin6. Finally, the PICRUSt2 analysis indicated that the potential metabolisms of carbohydrates, cofactors, amino acids, terpenoids, polyketides, lipids and antibiotic resistance were markedly enriched in PA than FL.
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26
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Müller O, Seuthe L, Pree B, Bratbak G, Larsen A, Paulsen ML. How Microbial Food Web Interactions Shape the Arctic Ocean Bacterial Community Revealed by Size Fractionation Experiments. Microorganisms 2021; 9:2378. [PMID: 34835503 PMCID: PMC8617753 DOI: 10.3390/microorganisms9112378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/10/2021] [Accepted: 11/12/2021] [Indexed: 11/30/2022] Open
Abstract
In the Arctic, seasonal changes are substantial, and as a result, the marine bacterial community composition and functions differ greatly between the dark winter and light-intensive summer. While light availability is, overall, the external driver of the seasonal changes, several internal biological interactions structure the bacterial community during shorter timescales. These include specific phytoplankton-bacteria associations, viral infections and other top-down controls. Here, we uncover these microbial interactions and their effects on the bacterial community composition during a full annual cycle by manipulating the microbial food web using size fractionation. The most profound community changes were detected during the spring, with 'mutualistic phytoplankton'-Gammaproteobacteria interactions dominating in the pre-bloom phase and 'substrate-dependent phytoplankton'-Flavobacteria interactions during blooming conditions. Bacterivores had an overall limited effect on the bacterial community composition most of the year. However, in the late summer, grazing was the main factor shaping the community composition and transferring carbon to higher trophic levels. Identifying these small-scale interactions improves our understanding of the Arctic marine microbial food web and its dynamics.
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Affiliation(s)
- Oliver Müller
- Department of Biological Sciences, University of Bergen, 5006 Bergen, Norway; (B.P.); (G.B.)
| | - Lena Seuthe
- Department of Arctic and Marine Biology, UiT—The Arctic University of Norway, 9037 Tromsø, Norway;
| | - Bernadette Pree
- Department of Biological Sciences, University of Bergen, 5006 Bergen, Norway; (B.P.); (G.B.)
| | - Gunnar Bratbak
- Department of Biological Sciences, University of Bergen, 5006 Bergen, Norway; (B.P.); (G.B.)
| | - Aud Larsen
- Molecular Ecology Group, NORCE, 5008 Bergen, Norway;
| | - Maria Lund Paulsen
- Arctic Research Center, Department of Ecoscience, Aarhus University, 8600 Silkeborg, Denmark;
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27
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Valencia B, Stukel MR, Allen AE, McCrow JP, Rabines A, Palenik B, Landry MR. Relating sinking and suspended microbial communities in the California Current Ecosystem: digestion resistance and the contributions of phytoplankton taxa to export. Environ Microbiol 2021; 23:6734-6748. [PMID: 34431195 DOI: 10.1111/1462-2920.15736] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 08/21/2021] [Indexed: 11/27/2022]
Abstract
We used 16S, 18S, plastid and internal transcribed spacer (for Synechococcus strains) sequencing to quantify relative microbial abundances in water-column samples and on sediment-trap-collected particles across an environmental gradient in the California Current Ecosystem (CCE) spanning a > 60-fold range of surface chlorophyll. Most mixed-layer dominant eukaryotes and prokaryotes were consistently underrepresented on sinking particles. Diatoms were the only phototrophic taxa consistently overrepresented. Even within this class, however, one genus (Thalassiosira) was a particle-enriched dominant, while a similarly abundant species was poorly represented. Synechococcus was significantly enriched on sinking particles at only one of four sites, but clade I was disproportionately abundant on sinking particles throughout the region compared with clade IV, the euphotic-zone co-dominant. The most abundant microbes on particles across the CCE were organisms with distributional maxima close to the sediment-trap depth (rhizarians), microbes associated with metazoans or sinking particles as a nutritional habitat (certain alveolates, Gammaproteobacteria) and organisms that resist digestive degradation of their DNA (Thalassiosira, Synechococcus). For assessing taxon contributions of phytoplankton to carbon export, our results highlight the need for sequence-based quantitative approaches that can be used to integrate euphotic-zone abundances, compute rates and account for taxon differences in preservation of sequence markers through trophic processing.
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Affiliation(s)
- Bellineth Valencia
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, USA
| | - Michael R Stukel
- Earth, Ocean, and Atmospheric Science Department, Florida State University, Tallahassee, FL, USA
| | - Andrew E Allen
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, USA.,Microbial and Environmental Genomics, J Craig Venter Institute, La Jolla, CA, USA
| | - John P McCrow
- Microbial and Environmental Genomics, J Craig Venter Institute, La Jolla, CA, USA
| | - Ariel Rabines
- Microbial and Environmental Genomics, J Craig Venter Institute, La Jolla, CA, USA
| | - Brian Palenik
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, USA
| | - Michael R Landry
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, USA
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28
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Harke MJ, Frischkorn KR, Hennon GMM, Haley ST, Barone B, Karl DM, Dyhrman ST. Microbial community transcriptional patterns vary in response to mesoscale forcing in the North Pacific Subtropical Gyre. Environ Microbiol 2021; 23:4807-4822. [PMID: 34309154 DOI: 10.1111/1462-2920.15677] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Accepted: 07/18/2021] [Indexed: 11/30/2022]
Abstract
The physical and biological dynamics that influence phytoplankton communities in the oligotrophic ocean are complex, changing across broad temporal and spatial scales. Eukaryotic phytoplankton (e.g., diatoms), despite their relatively low abundance in oligotrophic waters, are responsible for a large component of the organic matter flux to the ocean interior. Mesoscale eddies can impact both microbial community structure and function, enhancing primary production and carbon export, but the mechanisms that underpin these dynamics are still poorly understood. Here, mesoscale eddy influences on the taxonomic diversity and expressed functional profiles of surface communities of microeukaryotes and particle-associated heterotrophic bacteria from the North Pacific Subtropical Gyre were assessed over 2 years (spring 2016 and summer 2017). The taxonomic diversity of the microeukaryotes significantly differed by eddy polarity (cyclonic versus anticyclonic) and between sampling seasons/years and was significantly correlated with the taxonomic diversity of particle-associated heterotrophic bacteria. The expressed functional profile of these taxonomically distinct microeukaryotes varied consistently as a function of eddy polarity, with cyclones having a different expression pattern than anticyclones, and between sampling seasons/years. These data suggest that mesoscale forcing, and associated changes in biogeochemistry, could drive specific physiological responses in the resident microeukaryote community, independent of species composition.
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Affiliation(s)
- Matthew J Harke
- Lamont-Doherty Earth Observatory, Biology and Paleo Environment, Columbia University, Palisades, NY, USA.,Gloucester Marine Genomics Institute, Gloucester, MA, USA
| | - Kyle R Frischkorn
- Lamont-Doherty Earth Observatory, Biology and Paleo Environment, Columbia University, Palisades, NY, USA
| | - Gwenn M M Hennon
- Lamont-Doherty Earth Observatory, Biology and Paleo Environment, Columbia University, Palisades, NY, USA.,College of Fisheries and Ocean Sciences, University of Alaska, Fairbanks, AK, USA
| | - Sheean T Haley
- Lamont-Doherty Earth Observatory, Biology and Paleo Environment, Columbia University, Palisades, NY, USA
| | - Benedetto Barone
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, University of Hawaii at Manoa, Honolulu, HI, USA.,Department of Oceanography, University of Hawaii at Manoa, Honolulu, HI, USA
| | - David M Karl
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, University of Hawaii at Manoa, Honolulu, HI, USA.,Department of Oceanography, University of Hawaii at Manoa, Honolulu, HI, USA
| | - Sonya T Dyhrman
- Lamont-Doherty Earth Observatory, Biology and Paleo Environment, Columbia University, Palisades, NY, USA.,Department of Earth and Environmental Sciences, Columbia University, New York, NY, USA
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29
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Ferguson RMW, O'Gorman EJ, McElroy DJ, McKew BA, Coleman RA, Emmerson MC, Dumbrell AJ. The ecological impacts of multiple environmental stressors on coastal biofilm bacteria. GLOBAL CHANGE BIOLOGY 2021; 27:3166-3178. [PMID: 33797829 DOI: 10.1111/gcb.15626] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 03/04/2021] [Indexed: 06/12/2023]
Abstract
Ecological communities are increasingly exposed to multiple interacting stressors. For example, warming directly affects the physiology of organisms, eutrophication stimulates the base of the food web, and harvesting larger organisms for human consumption dampens top-down control. These stressors often combine in the natural environment with unpredictable results. Bacterial communities in coastal ecosystems underpin marine food webs and provide many important ecosystem services (e.g. nutrient cycling and carbon fixation). Yet, how microbial communities will respond to a changing climate remains uncertain. Thus, we used marine mesocosms to examine the impacts of warming, nutrient enrichment, and altered top-predator population size structure (common shore crab) on coastal microbial biofilm communities in a crossed experimental design. Warming increased bacterial α-diversity (18% increase in species richness and 67% increase in evenness), but this was countered by a decrease in α-diversity with nutrient enrichment (14% and 21% decrease for species richness and evenness, respectively). Thus, we show some effects of these stressors could cancel each other out under climate change scenarios. Warming and top-predator population size structure both affected bacterial biofilm community composition, with warming increasing the abundance of bacteria capable of increased mineralization of dissolved and particulate organic matter, such as Flavobacteriia, Sphingobacteriia, and Cytophagia. However, the community shifts observed with warming depended on top-predator population size structure, with Sphingobacteriia increasing with smaller crabs and Cytophagia increasing with larger crabs. These changes could alter the balance between mineralization and carbon sequestration in coastal ecosystems, leading to a positive feedback loop between warming and CO2 production. Our results highlight the potential for warming to disrupt microbial communities and biogeochemical cycling in coastal ecosystems, and the importance of studying these effects in combination with other environmental stressors.
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Affiliation(s)
| | - Eoin J O'Gorman
- School of Life Sciences, University of Essex, Colchester, UK
| | - David J McElroy
- Coastal & Marine Ecosystems Group, School of Biological Sciences, University of Sydney, Sydney, NSW, Australia
- Marine Stewardship Council, London, UK
| | - Boyd A McKew
- School of Life Sciences, University of Essex, Colchester, UK
| | - Ross A Coleman
- Coastal & Marine Ecosystems Group, School of Biological Sciences, University of Sydney, Sydney, NSW, Australia
| | - Mark C Emmerson
- School of Biological Sciences, Queen's University Belfast, Belfast, UK
| | - Alex J Dumbrell
- School of Life Sciences, University of Essex, Colchester, UK
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30
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Wei W, Wang L, Fang J, Liu R. Population structure, activity potential and ecotype partitioning of Pseudoalteromonas along the vertical water column of the New Britain Trench. FEMS Microbiol Lett 2021; 368:6308368. [PMID: 34160584 DOI: 10.1093/femsle/fnab078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Accepted: 06/21/2021] [Indexed: 11/14/2022] Open
Abstract
Microbial degradation of organic matter along the vertical profile of the water column is a major process driving the carbon cycle in the ocean. Pseudoalteromonas has been identified as a dominant genus in pelagic marine environments worldwide, playing important roles in the remineralization of organic carbon. However, the current understanding of Pseudoalteromonas was mainly based on shallow water populations or cultivated species. This study analyzed for the first time the structure, activity potential and ecotypes differentiation of Pseudoalteromonas in the water column of the New Britain Trench (NBT) down to 6000 m. Analysis on diversities of the 16S rRNA gene and their transcripts showed that Pseudoalteromonas was greatly enriched in deep-sea waters and showed high activity potentials. The deep-sea Pseudoalteromonas were significantly different from their shallow-water counterparts, suggesting an obvious ecotype division along with the vertical profile. Phylogenetic analysis on the 16S rRNA gene and hsp60 gene of 219 Pseudoalteromonas strains isolated from different depths further showed that the vertical ecotype division could even occur at the strain level, which might be a result of long-term adaptation to environmental conditions at different depths. The discovered depth-specific strains provide valuable models for further studies on adaptation, evolution and functions of the deep-sea Pseudoalteromonas.
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Affiliation(s)
- Wenxia Wei
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai,201306, China.,National Engineering Research Center for Oceanic Fisheries, Shanghai Ocean University, Shanghai, 201306, China
| | - Li Wang
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai,201306, China.,National Engineering Research Center for Oceanic Fisheries, Shanghai Ocean University, Shanghai, 201306, China
| | - Jiasong Fang
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai,201306, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao,266000, China.,Department of Natural Sciences, Hawaii Pacific University, Honolulu, HI 96813, USA
| | - Rulong Liu
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai,201306, China.,National Engineering Research Center for Oceanic Fisheries, Shanghai Ocean University, Shanghai, 201306, China
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31
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Suominen S, Doorenspleet K, Sinninghe Damsté JS, Villanueva L. Microbial community development on model particles in the deep sulfidic waters of the Black Sea. Environ Microbiol 2021; 23:2729-2746. [PMID: 32291864 PMCID: PMC8359284 DOI: 10.1111/1462-2920.15024] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 04/01/2020] [Accepted: 04/12/2020] [Indexed: 12/31/2022]
Abstract
Microorganisms attached to particles have been shown to be different from free-living microbes and to display diverse metabolic activities. However, little is known about the ecotypes associated with particles and their substrate preference in anoxic marine waters. Here, we investigate the microbial community colonizing particles in the anoxic and sulfide-rich waters of the Black Sea. We incubated beads coated with different substrates in situ at 1000 and 2000 m depth. After 6 h, the particle-attached microbes were dominated by Gamma- and Alpha-proteobacteria, and groups related to the phyla Latescibacteria, Bacteroidetes, Planctomycetes and Firmicutes, with substantial variation across the bead types, indicating that the attaching communities were selected by the substrate. Further laboratory incubations for 7 days suggested the presence of a community of highly specialized taxa. After incubation for 35 days, the microbial composition across all beads and depths was similar and primarily composed of putative sulfur cycling microbes. In addition to the major shared microbial groups, subdominant taxa on chitin and protein-coated beads were detected pointing to specialized microbial degraders. These results highlight the role of particles as sites for attachment and biofilm formation, while the composition of organic matter defined a secondary part of the microbial community.
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Affiliation(s)
- Saara Suominen
- Department of Marine Microbiology and BiogeochemistryNIOZ Royal Netherlands Institute for Sea Research and Utrecht UniversityDen BurgThe Netherlands
| | - Karlijn Doorenspleet
- Department of Marine Microbiology and BiogeochemistryNIOZ Royal Netherlands Institute for Sea Research and Utrecht UniversityDen BurgThe Netherlands
| | - Jaap S. Sinninghe Damsté
- Department of Marine Microbiology and BiogeochemistryNIOZ Royal Netherlands Institute for Sea Research and Utrecht UniversityDen BurgThe Netherlands
- Department of Earth Sciences, Faculty of GeosciencesUtrecht UniversityUtrecht, The Netherlands
| | - Laura Villanueva
- Department of Marine Microbiology and BiogeochemistryNIOZ Royal Netherlands Institute for Sea Research and Utrecht UniversityDen BurgThe Netherlands
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Heins A, Reintjes G, Amann RI, Harder J. Particle Collection in Imhoff Sedimentation Cones Enriches Both Motile Chemotactic and Particle-Attached Bacteria. Front Microbiol 2021; 12:643730. [PMID: 33868201 PMCID: PMC8047139 DOI: 10.3389/fmicb.2021.643730] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 03/01/2021] [Indexed: 11/13/2022] Open
Abstract
Marine heterotrophic microorganisms remineralize about half of the annual primary production, with the microbiomes on and around algae and particles having a major contribution. These microbiomes specifically include free-living chemotactic and particle-attached bacteria, which are often difficult to analyze individually, as the standard method of size-selective filtration only gives access to particle-attached bacteria. In this study, we demonstrated that particle collection in Imhoff sedimentation cones enriches microbiomes that included free-living chemotactic bacteria and were distinct from particle microbiomes obtained by filtration or centrifugation. Coastal seawater was collected during North Sea phytoplankton spring blooms, and the microbiomes were investigated using 16S rRNA amplicon sequencing and fluorescence microscopy. Enrichment factors of individual operational taxonomic units (OTUs) were calculated for comparison of fractionated communities after separation with unfractionated seawater communities. Filtration resulted in a loss of cells and yielded particle fractions including bacterial aggregates, filaments, and large cells. Centrifugation had the lowest separation capacity. Particles with a sinking rate of >2.4 m day-1 were collected in sedimentation cones as a bottom fraction and enriched in free-living chemotactic bacteria, i.e., Sulfitobacter, Pseudoalteromonas, and Vibrio. Subfractions of these bottom fractions, obtained by centrifugation, showed enrichment of either free-living or particle-attached bacteria. We identified five distinct enrichment patterns across all separation techniques: mechano-sensitive and mechano-stable free-living bacteria and three groups of particle-attached bacteria. Simultaneous enrichment of particle-attached and chemotactic free-living bacteria in Imhoff sedimentation cones is a novel experimental access to these groups providing more insights into the diversity, structure, and function of particle-associated microbiomes, including members of the phycosphere.
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Affiliation(s)
- Anneke Heins
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Greta Reintjes
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany.,Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, AB, Canada
| | - Rudolf I Amann
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Jens Harder
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
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DeLong EF. Genome-enabled exploration of microbial ecology and evolution in the sea: a rising tide lifts all boats. Environ Microbiol 2021; 23:1301-1321. [PMID: 33459471 PMCID: PMC8049014 DOI: 10.1111/1462-2920.15403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 01/15/2021] [Indexed: 11/26/2022]
Abstract
As a young bacteriologist just launching my career during the early days of the 'microbial revolution' in the 1980s, I was fortunate to participate in some early discoveries, and collaborate in the development of cross-disciplinary methods now commonly referred to as "metagenomics". My early scientific career focused on applying phylogenetic and genomic approaches to characterize 'wild' bacteria, archaea and viruses in their natural habitats, with an emphasis on marine systems. These central interests have not changed very much for me over the past three decades, but knowledge, methodological advances and new theoretical perspectives about the microbial world certainly have. In this invited 'How we did it' perspective, I trace some of the trajectories of my lab's collective efforts over the years, including phylogenetic surveys of microbial assemblages in marine plankton and sediments, development of microbial community gene- and genome-enabled surveys, and application of genome-guided, cultivation-independent functional characterization of novel enzymes, pathways and their relationships to in situ biogeochemistry. Throughout this short review, I attempt to acknowledge, all the mentors, students, postdocs and collaborators who enabled this research. Inevitably, a brief autobiographical review like this cannot be fully comprehensive, so sincere apologies to any of my great colleagues who are not explicitly mentioned herein. I salute you all as well!
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Affiliation(s)
- Edward F DeLong
- Daniel K. Inouye Centre for Microbial Oceanography: Research and Education, University of Hawaii, Manoa, Honolulu, HI, 96822, USA
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34
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Ponsero AJ, Bomhoff M, Blumberg K, Youens-Clark K, Herz NM, Wood-Charlson EM, Delong EF, Hurwitz BL. Planet Microbe: a platform for marine microbiology to discover and analyze interconnected 'omics and environmental data. Nucleic Acids Res 2021; 49:D792-D802. [PMID: 32735679 PMCID: PMC7778950 DOI: 10.1093/nar/gkaa637] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 06/23/2020] [Accepted: 07/20/2020] [Indexed: 12/27/2022] Open
Abstract
In recent years, large-scale oceanic sequencing efforts have provided a deeper understanding of marine microbial communities and their dynamics. These research endeavors require the acquisition of complex and varied datasets through large, interdisciplinary and collaborative efforts. However, no unifying framework currently exists for the marine science community to integrate sequencing data with physical, geological, and geochemical datasets. Planet Microbe is a web-based platform that enables data discovery from curated historical and on-going oceanographic sequencing efforts. In Planet Microbe, each ‘omics sample is linked with other biological and physiochemical measurements collected for the same water samples or during the same sample collection event, to provide a broader environmental context. This work highlights the need for curated aggregation efforts that can enable new insights into high-quality metagenomic datasets. Planet Microbe is freely accessible from https://www.planetmicrobe.org/.
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Affiliation(s)
- Alise J Ponsero
- Department of Biosystems Engineering, University of Arizona, Tucson, AZ, USA.,BIO5 Institute, University of Arizona, Tucson, AZ, USA
| | - Matthew Bomhoff
- Department of Biosystems Engineering, University of Arizona, Tucson, AZ, USA.,BIO5 Institute, University of Arizona, Tucson, AZ, USA
| | - Kai Blumberg
- Department of Biosystems Engineering, University of Arizona, Tucson, AZ, USA.,BIO5 Institute, University of Arizona, Tucson, AZ, USA
| | - Ken Youens-Clark
- Department of Biosystems Engineering, University of Arizona, Tucson, AZ, USA.,BIO5 Institute, University of Arizona, Tucson, AZ, USA
| | - Nina M Herz
- Department of Biosystems Engineering, University of Arizona, Tucson, AZ, USA
| | - Elisha M Wood-Charlson
- Environmental Genomics and Systems Biology Division, E.O. Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Edward F Delong
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, University of Hawaii, Manoa, Honolulu, HI 96822, USA
| | - Bonnie L Hurwitz
- Department of Biosystems Engineering, University of Arizona, Tucson, AZ, USA.,BIO5 Institute, University of Arizona, Tucson, AZ, USA
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Abstract
The ocean’s “biological pump” exports sinking particles containing carbon, nutrients, and energy to the deep sea, contributing centrally to the global carbon cycle. Here, we identify key organisms and biological processes associated with elevated carbon flux to the abyss. Our analyses reveal that, during summer export, specific populations of photosynthetic algae, heterotrophic protists, and bacteria reach the abyss on sinking particles. Deep-sea bacteria respond rapidly to this elevated nutrient delivery to the abyss in summer. During other seasons, different organisms and processes appear responsible for particle export to the deep sea. Our analyses reveal key biota and biological processes that interconnect surface productivity, particle export, and the deep-sea ecosystem, thereby influencing the function and efficiency of the ocean’s biological pump. In the open ocean, elevated carbon flux (ECF) events increase the delivery of particulate carbon from surface waters to the seafloor by severalfold compared to other times of year. Since microbes play central roles in primary production and sinking particle formation, they contribute greatly to carbon export to the deep sea. Few studies, however, have quantitatively linked ECF events with the specific microbial assemblages that drive them. Here, we identify key microbial taxa and functional traits on deep-sea sinking particles that correlate positively with ECF events. Microbes enriched on sinking particles in summer ECF events included symbiotic and free-living diazotrophic cyanobacteria, rhizosolenid diatoms, phototrophic and heterotrophic protists, and photoheterotrophic and copiotrophic bacteria. Particle-attached bacteria reaching the abyss during summer ECF events encoded metabolic pathways reflecting their surface water origins, including oxygenic and aerobic anoxygenic photosynthesis, nitrogen fixation, and proteorhodopsin-based photoheterotrophy. The abundances of some deep-sea bacteria also correlated positively with summer ECF events, suggesting rapid bathypelagic responses to elevated organic matter inputs. Biota enriched on sinking particles during a spring ECF event were distinct from those found in summer, and included rhizaria, copepods, fungi, and different bacterial taxa. At other times over our 3-y study, mid- and deep-water particle colonization, predation, degradation, and repackaging (by deep-sea bacteria, protists, and animals) appeared to shape the biotic composition of particles reaching the abyss. Our analyses reveal key microbial players and biological processes involved in particle formation, rapid export, and consumption, that may influence the ocean’s biological pump and help sustain deep-sea ecosystems.
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Alcamán-Arias ME, Fuentes-Alburquenque S, Vergara-Barros P, Cifuentes-Anticevic J, Verdugo J, Polz M, Farías L, Pedrós-Alió C, Díez B. Coastal Bacterial Community Response to Glacier Melting in the Western Antarctic Peninsula. Microorganisms 2021; 9:microorganisms9010088. [PMID: 33401391 PMCID: PMC7823458 DOI: 10.3390/microorganisms9010088] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/20/2020] [Accepted: 12/21/2020] [Indexed: 01/04/2023] Open
Abstract
Current warming in the Western Antarctic Peninsula (WAP) has multiple effects on the marine ecosystem, modifying the trophic web and the nutrient regime. In this study, the effect of decreased surface salinity on the marine microbial community as a consequence of freshening from nearby glaciers was investigated in Chile Bay, Greenwich Island, WAP. In the summer of 2016, samples were collected from glacier ice and transects along the bay for 16S rRNA gene sequencing, while in situ dilution experiments were conducted and analyzed using 16S rRNA gene sequencing and metatranscriptomic analysis. The results reveal that certain common seawater genera, such as Polaribacter, Pseudoalteromonas and HTCC2207, responded positively to decreased salinity in both the bay transect and experiments. The relative abundance of these bacteria slightly decreased, but their functional activity was maintained and increased the over time in the dilution experiments. However, while ice bacteria, such as Flavobacterium and Polaromonas, tolerated the increased salinity after mixing with seawater, their gene expression decreased considerably. We suggest that these bacterial taxa could be defined as sentinels of freshening events in the Antarctic coastal system. Furthermore, these results suggest that a significant portion of the microbial community is resilient and can adapt to disturbances, such as freshening due to the warming effect of climate change in Antarctica.
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Affiliation(s)
- María Estrella Alcamán-Arias
- Department of Oceanography, Universidad de Concepcion, Concepcion 4030000, Chile; (M.E.A.-A.); (L.F.)
- Center for Climate and Resilience Research (CR)2, Santiago 8320000, Chile
- Escuela de Medicina, Universidad Espíritu Santo, Guayaquil 0901952, Ecuador
| | - Sebastián Fuentes-Alburquenque
- Centro de Investigación en Recursos Naturales y Sustentabilidad, Universidad Bernardo O’Higgins, Santiago 8370993, Chile;
- Facultad de Ingeniería, Ciencia y Tecnología, Universidad Bernardo O’Higgins, Santiago 8370993, Chile
| | - Pablo Vergara-Barros
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile; (P.V.-B.); (J.C.-A.)
| | - Jerónimo Cifuentes-Anticevic
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile; (P.V.-B.); (J.C.-A.)
| | - Josefa Verdugo
- Alfred-Wegener-Institute, Helmholtz-Centre for Polar and Marine Research, 27570 Bremerhaven, Germany;
| | - Martin Polz
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA;
| | - Laura Farías
- Department of Oceanography, Universidad de Concepcion, Concepcion 4030000, Chile; (M.E.A.-A.); (L.F.)
- Center for Climate and Resilience Research (CR)2, Santiago 8320000, Chile
| | - Carlos Pedrós-Alió
- Departamento de Biología de Sistemas, Centro Nacional de Biotecnología (CSIC), Darwin 3, 28049 Madrid, Spain;
| | - Beatriz Díez
- Center for Climate and Resilience Research (CR)2, Santiago 8320000, Chile
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile; (P.V.-B.); (J.C.-A.)
- Correspondence:
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Shibl AA, Isaac A, Ochsenkühn MA, Cárdenas A, Fei C, Behringer G, Arnoux M, Drou N, Santos MP, Gunsalus KC, Voolstra CR, Amin SA. Diatom modulation of select bacteria through use of two unique secondary metabolites. Proc Natl Acad Sci U S A 2020; 117:27445-27455. [PMID: 33067398 PMCID: PMC7959551 DOI: 10.1073/pnas.2012088117] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Unicellular eukaryotic phytoplankton, such as diatoms, rely on microbial communities for survival despite lacking specialized compartments to house microbiomes (e.g., animal gut). Microbial communities have been widely shown to benefit from diatom excretions that accumulate within the microenvironment surrounding phytoplankton cells, known as the phycosphere. However, mechanisms that enable diatoms and other unicellular eukaryotes to nurture specific microbiomes by fostering beneficial bacteria and repelling harmful ones are mostly unknown. We hypothesized that diatom exudates may tune microbial communities and employed an integrated multiomics approach using the ubiquitous diatom Asterionellopsis glacialis to reveal how it modulates its naturally associated bacteria. We show that A. glacialis reprograms its transcriptional and metabolic profiles in response to bacteria to secrete a suite of central metabolites and two unusual secondary metabolites, rosmarinic acid and azelaic acid. While central metabolites are utilized by potential bacterial symbionts and opportunists alike, rosmarinic acid promotes attachment of beneficial bacteria to the diatom and simultaneously suppresses the attachment of opportunists. Similarly, azelaic acid enhances growth of beneficial bacteria while simultaneously inhibiting growth of opportunistic ones. We further show that the bacterial response to azelaic acid is numerically rare but globally distributed in the world's oceans and taxonomically restricted to a handful of bacterial genera. Our results demonstrate the innate ability of an important unicellular eukaryotic group to modulate select bacteria in their microbial consortia, similar to higher eukaryotes, using unique secondary metabolites that regulate bacterial growth and behavior inversely across different bacterial populations.
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Affiliation(s)
- Ahmed A Shibl
- Marine Microbial Ecology Laboratory, Biology Program, New York University Abu Dhabi, Abu Dhabi 129188, United Arab Emirates
| | - Ashley Isaac
- Marine Microbial Ecology Laboratory, Biology Program, New York University Abu Dhabi, Abu Dhabi 129188, United Arab Emirates
- International Max Planck Research School of Marine Microbiology, University of Bremen, Bremen 28334, Germany
| | - Michael A Ochsenkühn
- Marine Microbial Ecology Laboratory, Biology Program, New York University Abu Dhabi, Abu Dhabi 129188, United Arab Emirates
| | - Anny Cárdenas
- Department of Biology, University of Konstanz, Konstanz 78467, Germany
- Red Sea Research Center, Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Cong Fei
- Marine Microbial Ecology Laboratory, Biology Program, New York University Abu Dhabi, Abu Dhabi 129188, United Arab Emirates
| | - Gregory Behringer
- Marine Microbial Ecology Laboratory, Biology Program, New York University Abu Dhabi, Abu Dhabi 129188, United Arab Emirates
| | - Marc Arnoux
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi 129188, United Arab Emirates
| | - Nizar Drou
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi 129188, United Arab Emirates
| | - Miraflor P Santos
- Marine Microbial Ecology Laboratory, Biology Program, New York University Abu Dhabi, Abu Dhabi 129188, United Arab Emirates
| | - Kristin C Gunsalus
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi 129188, United Arab Emirates
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, NY 10003
| | - Christian R Voolstra
- Department of Biology, University of Konstanz, Konstanz 78467, Germany
- Red Sea Research Center, Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Shady A Amin
- Marine Microbial Ecology Laboratory, Biology Program, New York University Abu Dhabi, Abu Dhabi 129188, United Arab Emirates;
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Peoples LM, Kyaw TS, Ugalde JA, Mullane KK, Chastain RA, Yayanos AA, Kusube M, Methé BA, Bartlett DH. Distinctive gene and protein characteristics of extremely piezophilic Colwellia. BMC Genomics 2020; 21:692. [PMID: 33023469 PMCID: PMC7542103 DOI: 10.1186/s12864-020-07102-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 09/24/2020] [Indexed: 01/05/2023] Open
Abstract
Background The deep ocean is characterized by low temperatures, high hydrostatic pressures, and low concentrations of organic matter. While these conditions likely select for distinct genomic characteristics within prokaryotes, the attributes facilitating adaptation to the deep ocean are relatively unexplored. In this study, we compared the genomes of seven strains within the genus Colwellia, including some of the most piezophilic microbes known, to identify genomic features that enable life in the deep sea. Results Significant differences were found to exist between piezophilic and non-piezophilic strains of Colwellia. Piezophilic Colwellia have a more basic and hydrophobic proteome. The piezophilic abyssal and hadal isolates have more genes involved in replication/recombination/repair, cell wall/membrane biogenesis, and cell motility. The characteristics of respiration, pilus generation, and membrane fluidity adjustment vary between the strains, with operons for a nuo dehydrogenase and a tad pilus only present in the piezophiles. In contrast, the piezosensitive members are unique in having the capacity for dissimilatory nitrite and TMAO reduction. A number of genes exist only within deep-sea adapted species, such as those encoding d-alanine-d-alanine ligase for peptidoglycan formation, alanine dehydrogenase for NADH/NAD+ homeostasis, and a SAM methyltransferase for tRNA modification. Many of these piezophile-specific genes are in variable regions of the genome near genomic islands, transposases, and toxin-antitoxin systems. Conclusions We identified a number of adaptations that may facilitate deep-sea radiation in members of the genus Colwellia, as well as in other piezophilic bacteria. An enrichment in more basic and hydrophobic amino acids could help piezophiles stabilize and limit water intrusion into proteins as a result of high pressure. Variations in genes associated with the membrane, including those involved in unsaturated fatty acid production and respiration, indicate that membrane-based adaptations are critical for coping with high pressure. The presence of many piezophile-specific genes near genomic islands highlights that adaptation to the deep ocean may be facilitated by horizontal gene transfer through transposases or other mobile elements. Some of these genes are amenable to further study in genetically tractable piezophilic and piezotolerant deep-sea microorganisms.
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Affiliation(s)
- Logan M Peoples
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, 92093-0202, USA.,Flathead Lake Biological Station, University of Montana, Polson, MT, 59860, USA
| | - Than S Kyaw
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, 92093-0202, USA
| | - Juan A Ugalde
- Millennium Initiative for Collaborative Research on Bacterial Resistance (MICROB-R), Santiago, Chile
| | - Kelli K Mullane
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, 92093-0202, USA
| | - Roger A Chastain
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, 92093-0202, USA
| | - A Aristides Yayanos
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, 92093-0202, USA
| | - Masataka Kusube
- Department of Material Science, National Institute of Technology, Wakayama College, 77 Noshima, Nada-cho, Gobo, Wakayama, 644-0023, Japan
| | - Barbara A Methé
- Center for Microbiome and Medicine, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Douglas H Bartlett
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, 92093-0202, USA.
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Zhang L, Lv J. Metagenomic analysis of microbial community and function reveals the response of soil respiration to the conversion of cropland to plantations in the Loess Plateau of China. Glob Ecol Conserv 2020. [DOI: 10.1016/j.gecco.2020.e01067] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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40
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Liu Y, Lin Q, Feng J, Yang F, Du H, Hu Z, Wang H. Differences in metabolic potential between particle-associated and free-living bacteria along Pearl River Estuary. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 728:138856. [PMID: 32570327 DOI: 10.1016/j.scitotenv.2020.138856] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 04/15/2020] [Accepted: 04/19/2020] [Indexed: 06/11/2023]
Abstract
Particulate organic matter (POM) in aquatic ecosystem is critical for biogeochemical cycling and host distinct communities of microbes, compared to its surrounding water. In this study, the structures and functional potentials of microbial communities associated with particles or free-living in water samples from the Pearl River Estuary were investigated using 16S rRNA gene sequencing and GeoChip 5.0 analysis. Significant differences in the community structure and genetic functional potentials between particle-associated bacteria and free-living bacteria were observed across all eight sampling sites. In particle-associated bacteria communities, Rhodobacteraceae and Flavobacteriaceae were more abundant, while SAR11 clade and SAR86 clade were the most abundant in free-living bacteria communities. The richness and abundance of functional genes involved in nutrient cycling and stress response, including carbon degradation, nitrogen fixation, DMSP degradation, and polyphosphate degradation, were much higher in particle-associated bacteria compared with free-living bacteria. Thus, the particle-associated bacteria seem to play a much more important role in the biogeochemical cycles than free-living bacteria. In conclusion, the results from this study highlight the central role played by particle-associated bacteria in structuring microbial assemblages, and their importance for mediating biogeochemical cycling in the estuarine ecosystem.
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Affiliation(s)
- Yanyang Liu
- Biology Department, College of Science, Shantou University, Shantou 515063, China; Institute of Marine Sciences, Shantou University, Shantou 515063, China; Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China
| | - Qun Lin
- Biology Department, College of Science, Shantou University, Shantou 515063, China; Institute of Marine Sciences, Shantou University, Shantou 515063, China; Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China
| | - Jiarong Feng
- Biology Department, College of Science, Shantou University, Shantou 515063, China; Institute of Marine Sciences, Shantou University, Shantou 515063, China; Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China
| | - Fumin Yang
- Biology Department, College of Science, Shantou University, Shantou 515063, China; Institute of Marine Sciences, Shantou University, Shantou 515063, China; Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China
| | - Hong Du
- Biology Department, College of Science, Shantou University, Shantou 515063, China; Institute of Marine Sciences, Shantou University, Shantou 515063, China; Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China
| | - Zhong Hu
- Biology Department, College of Science, Shantou University, Shantou 515063, China; Institute of Marine Sciences, Shantou University, Shantou 515063, China; Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China
| | - Hui Wang
- Biology Department, College of Science, Shantou University, Shantou 515063, China; Institute of Marine Sciences, Shantou University, Shantou 515063, China; Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China.
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Puigcorbé V, Ruiz-González C, Masqué P, Gasol JM. Sampling Device-Dependence of Prokaryotic Community Structure on Marine Particles: Higher Diversity Recovered by in situ Pumps Than by Oceanographic Bottles. Front Microbiol 2020; 11:1645. [PMID: 32760385 PMCID: PMC7373737 DOI: 10.3389/fmicb.2020.01645] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Accepted: 06/24/2020] [Indexed: 01/24/2023] Open
Abstract
Microbes associated with sinking marine particles play key roles in carbon sequestration in the ocean. The sampling of particle-attached microorganisms is often done with sediment traps or by filtration of water collected with oceanographic bottles, both involving a certain time lapse between collection and processing of samples that may result in changes in particle-attached microbial communities. Conversely, in situ water filtration through submersible pumps allows a faster storage of sampled particles, but it has rarely been used to study the associated microbial communities and has never been compared to other particle-sampling methods in terms of the recovery of particle microbial diversity. Here we compared the prokaryotic communities attached to small (1–53 μm) and large (>53 μm) particles collected from the mesopelagic zone (100–300 m) of two Antarctic polynyas using in situ pumps (ISP) and oceanographic bottles (BTL). Each sampling method retrieved largely different particle-attached communities, suggesting that they capture different kinds of particles. These device-driven differences were greater for large particles than for small particles. Overall, the ISP recovered 1.5- to 3-fold more particle-attached bacterial taxa than the BTL, and different taxonomic groups were preferentially recovered by each method. In particular, typical particle-attached groups such as Planctomycetes and Deltaproteobacteria recovered with ISP were nearly absent from BTL samples. Our results suggest that the method used to sample marine particles has a strong influence in our view of their associated microbial communities.
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Affiliation(s)
- Viena Puigcorbé
- School of Science, Centre for Marine Ecosystems Research, Edith Cowan University, Joondalup, WA, Australia
| | - Clara Ruiz-González
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar (ICM-CSIC), Barcelona, Spain
| | - Pere Masqué
- School of Science, Centre for Marine Ecosystems Research, Edith Cowan University, Joondalup, WA, Australia.,Institut de Ciència i Tecnologia Ambientals (ICTA), Bellaterra, Spain.,Department of Physics, Autonomous University of Barcelona, Barcelona, Spain.,International Atomic Energy Agency, Monaco City, Monaco
| | - Josep M Gasol
- School of Science, Centre for Marine Ecosystems Research, Edith Cowan University, Joondalup, WA, Australia.,Department of Marine Biology and Oceanography, Institut de Ciències del Mar (ICM-CSIC), Barcelona, Spain
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42
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Manna V, Malfatti F, Banchi E, Cerino F, De Pascale F, Franzo A, Schiavon R, Vezzi A, Del Negro P, Celussi M. Prokaryotic Response to Phytodetritus-Derived Organic Material in Epi- and Mesopelagic Antarctic Waters. Front Microbiol 2020; 11:1242. [PMID: 32582131 PMCID: PMC7296054 DOI: 10.3389/fmicb.2020.01242] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 05/14/2020] [Indexed: 12/31/2022] Open
Abstract
Particulate organic matter (POM) export represents the underlying principle of the biological carbon pump, driving the carbon flux from the sunlit to the dark ocean. The efficiency of this process is tightly linked to the prokaryotic community, as >70% of POM respiration is carried out by particle-associated prokaryotes. In the Ross Sea, one of the most productive areas of the Southern Ocean, up to 50% of the surface primary production is exported to the mesopelagic ocean as POM. Recent evidence suggests that a significant fraction of the POM in this area is composed of intact phytoplankton cells. During austral summer 2017, we set up bottle enrichment experiments in which we amended free-living surface and deep prokaryotic communities with organic matter pools generated from native microplankton, mimicking the particle export that may derive from mild (1 μg of Chlorophyll a L-1) and intense (10 μg of Chlorophyll a L-1) phytoplankton bloom. Over a course of 4 days, we followed free-living and particle-attached prokaryotes' abundance, the degradation rates of polysaccharides, proteins and lipids, heterotrophic production as well as inorganic carbon utilization and prokaryotic community structure dynamics. Our results showed that several rare or undetected taxa in the initial community became dominant during the time course of the incubations and that different phytodetritus-derived organic matter sources induced specific changes in microbial communities, selecting for peculiar degradation and utilization processes spectra. Moreover, the features of the supplied detritus (in terms of microplankton taxa composition) determined different colonization dynamics and organic matter processing modes. Our study provides insights into the mechanisms underlying the prokaryotic utilization of phytodetritus, a significant pool of organic matter in the dark ocean.
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Affiliation(s)
- Vincenzo Manna
- Oceanography Division, Istituto Nazionale di Oceanografia e di Geofisica Sperimentale – OGS, Trieste, Italy
- Department of Life Sciences, Università degli Studi di Trieste, Trieste, Italy
| | - Francesca Malfatti
- Oceanography Division, Istituto Nazionale di Oceanografia e di Geofisica Sperimentale – OGS, Trieste, Italy
- Scripps Institution of Oceanography, University of California, San Diego, San Diego, CA, United States
| | - Elisa Banchi
- Oceanography Division, Istituto Nazionale di Oceanografia e di Geofisica Sperimentale – OGS, Trieste, Italy
| | - Federica Cerino
- Oceanography Division, Istituto Nazionale di Oceanografia e di Geofisica Sperimentale – OGS, Trieste, Italy
| | - Fabio De Pascale
- Department of Biology, Università degli Studi di Padova, Padua, Italy
| | - Annalisa Franzo
- Oceanography Division, Istituto Nazionale di Oceanografia e di Geofisica Sperimentale – OGS, Trieste, Italy
| | - Riccardo Schiavon
- Department of Biology, Università degli Studi di Padova, Padua, Italy
| | - Alessandro Vezzi
- Department of Biology, Università degli Studi di Padova, Padua, Italy
| | - Paola Del Negro
- Oceanography Division, Istituto Nazionale di Oceanografia e di Geofisica Sperimentale – OGS, Trieste, Italy
| | - Mauro Celussi
- Oceanography Division, Istituto Nazionale di Oceanografia e di Geofisica Sperimentale – OGS, Trieste, Italy
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43
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Ruiz-González C, Mestre M, Estrada M, Sebastián M, Salazar G, Agustí S, Moreno-Ostos E, Reche I, Álvarez-Salgado XA, Morán XAG, Duarte CM, Sala MM, Gasol JM. Major imprint of surface plankton on deep ocean prokaryotic structure and activity. Mol Ecol 2020; 29:1820-1838. [PMID: 32323882 DOI: 10.1111/mec.15454] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 03/12/2020] [Accepted: 04/16/2020] [Indexed: 01/06/2023]
Abstract
Deep ocean microbial communities rely on the organic carbon produced in the sunlit ocean, yet it remains unknown whether surface processes determine the assembly and function of bathypelagic prokaryotes to a larger extent than deep-sea physicochemical conditions. Here, we explored whether variations in surface phytoplankton assemblages across Atlantic, Pacific and Indian ocean stations can explain structural changes in bathypelagic (ca. 4,000 m) free-living and particle-attached prokaryotic communities (characterized through 16S rRNA gene sequencing), as well as changes in prokaryotic activity and dissolved organic matter (DOM) quality. We show that the spatial structuring of prokaryotic communities in the bathypelagic strongly followed variations in the abundances of surface dinoflagellates and ciliates, as well as gradients in surface primary productivity, but were less influenced by bathypelagic physicochemical conditions. Amino acid-like DOM components in the bathypelagic reflected variations of those components in surface waters, and seemed to control bathypelagic prokaryotic activity. The imprint of surface conditions was more evident in bathypelagic than in shallower mesopelagic (200-1,000 m) communities, suggesting a direct connectivity through fast-sinking particles that escape mesopelagic transformations. Finally, we identified a pool of endemic deep-sea prokaryotic taxa (including potentially chemoautotrophic groups) that appear less connected to surface processes than those bathypelagic taxa with a widespread vertical distribution. Our results suggest that surface planktonic communities shape the spatial structure of the bathypelagic microbiome to a larger extent than the local physicochemical environment, likely through determining the nature of the sinking particles and the associated prokaryotes reaching bathypelagic waters.
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Affiliation(s)
| | - Mireia Mestre
- Institut de Ciències del Mar (ICM-CSIC), Barcelona, Spain.,Centro FONDAP de Investigación en Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL), Universidad Austral de Chile, Valdivia, Chile.,Centro de Investigación Oceanográfica COPAS Sur-Austral, Departamento de Oceanografía, Universidad de Concepción, Concepción, Chile
| | - Marta Estrada
- Institut de Ciències del Mar (ICM-CSIC), Barcelona, Spain
| | - Marta Sebastián
- Institut de Ciències del Mar (ICM-CSIC), Barcelona, Spain.,Instituto de Oceanografía y Cambio Global, IOCAG, Universidad de Las Palmas de Gran Canaria (ULPGC), Las Palmas, Spain
| | - Guillem Salazar
- Institut de Ciències del Mar (ICM-CSIC), Barcelona, Spain.,Department of Biology, Institute of Microbiology and Swiss Institute of Bioinformatics, ETH Zurich, Zurich, Switzerland
| | - Susana Agustí
- Red Sea Research Center (RSRC), King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Enrique Moreno-Ostos
- Department of Ecology and Geology, Marine Ecology and Limnology Research Group, CEIMAR, University of Málaga, Málaga, Spain
| | - Isabel Reche
- Departamento de Ecología and Research Unit Modeling Nature (MNat), Universidad de Granada, Granada, Spain
| | | | - Xosé Anxelu G Morán
- Red Sea Research Center (RSRC), King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Carlos M Duarte
- Red Sea Research Center (RSRC), King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | | | - Josep M Gasol
- Institut de Ciències del Mar (ICM-CSIC), Barcelona, Spain.,Centre for Marine Ecosystems Research, School of Science, Edith Cowan University, Joondalup, WA, Australia
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44
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Distribution Patterns of Microeukaryotic Community Between Sediment and Water of the Yellow River Estuary. Curr Microbiol 2020; 77:1496-1505. [PMID: 32239287 DOI: 10.1007/s00284-020-01958-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 03/21/2020] [Indexed: 10/24/2022]
Abstract
Water and sediment have always been closely tied in aquatic systems. However, little information regarding the full extent of microeukaryotic composition in both the two habitats did we know especially in estuaries. In the present study, the microeukaryotic abundance, diversity, composition, and their response to environmental factors between sediment and water in the Yellow River Estuary (YRE) were investigated. The microeukaryotic 18S rRNA gene abundance ranged from 1.03 × 106 to 5.48 × 107 copies/g dry for sediment, and 3.01 × 104 to 1.25 × 106 copies/mL for water. The distribution patterns of eukaryotic microorganisms could be clustered into two different branches. And the compositions of microeukaryotes in the two habitats were distinct obviously. Metazoa, Fungi, Streptophyta, Ochrophyta, Cercozoa, and Dinophyta were more abundant in sediment. The dominant phyla in water were Dinophyta, followed by Metazoa, Ochrophyta, Cryptophyta, Chloroplyta, Cercozoa, Fungi, Katablepharidophyta, Choanoflagellida, and Haptophyta. Interestingly, the eukaryotic microorganisms detected in sediment were much less sensitive to environmental variables compared with water. Furthermore, their potential co-occurrence networks in particular were also discovered in the present study. As such, we have provided baseline data to support further research on estuarine microeukaryotes in both sediment and water, which was useful for guiding the practical application of ecosystem management and biodiversity protection.
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45
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Distinct capabilities of different Gammaproteobacterial strains on utilizing small peptides in seawater. Sci Rep 2020; 10:464. [PMID: 31949195 PMCID: PMC6965191 DOI: 10.1038/s41598-019-57189-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 12/21/2019] [Indexed: 11/23/2022] Open
Abstract
Proteins and peptides account for 20–75% of marine biota biomass, of which a major fraction is metabolized by bacteria, thus deciphering interactions between bacteria and peptides is important in understanding marine carbon and nitrogen cycling. To better understand capabilities of different bacterial strains on peptide decomposition, four Gammaproteobacteria (Pseudoalteromonas atlantica, Alteromonas sp., Marinobacterium jannaschii, Amphritea japonica) were incubated in autoclaved seawater amended with tetrapeptide alanine-valine-phenylalanine-alanine (AVFA), a fragment of RuBisCO. While AVFA was decomposed greatly by Pseudoalteromonas atlantica and Alteromonas sp, it remained nearly intact in the Marinobacterium jannaschii and Amphritea japonica incubations. Pseudoalteromonas and Alteromonas decomposed AVFA mainly through extracellular hydrolysis pathway, releasing 71–85% of the AVFA as hydrolysis products to the surrounding seawater. Overall, this study showed that Gammaproteobacterial strains differ greatly in their capabilities of metabolizing peptides physiologically, providing insights into interactions of bacteria and labile organic matter in marine environments.
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46
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Howard-Varona C, Lindback MM, Bastien GE, Solonenko N, Zayed AA, Jang H, Andreopoulos B, Brewer HM, Glavina Del Rio T, Adkins JN, Paul S, Sullivan MB, Duhaime MB. Phage-specific metabolic reprogramming of virocells. ISME JOURNAL 2020; 14:881-895. [PMID: 31896786 PMCID: PMC7082346 DOI: 10.1038/s41396-019-0580-z] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 11/25/2019] [Accepted: 12/17/2019] [Indexed: 12/22/2022]
Abstract
Ocean viruses are abundant and infect 20–40% of surface microbes. Infected cells, termed virocells, are thus a predominant microbial state. Yet, virocells and their ecosystem impacts are understudied, thus precluding their incorporation into ecosystem models. Here we investigated how unrelated bacterial viruses (phages) reprogram one host into contrasting virocells with different potential ecosystem footprints. We independently infected the marine Pseudoalteromonas bacterium with siphovirus PSA-HS2 and podovirus PSA-HP1. Time-resolved multi-omics unveiled drastically different metabolic reprogramming and resource requirements by each virocell, which were related to phage–host genomic complementarity and viral fitness. Namely, HS2 was more complementary to the host in nucleotides and amino acids, and fitter during infection than HP1. Functionally, HS2 virocells hardly differed from uninfected cells, with minimal host metabolism impacts. HS2 virocells repressed energy-consuming metabolisms, including motility and translation. Contrastingly, HP1 virocells substantially differed from uninfected cells. They repressed host transcription, responded to infection continuously, and drastically reprogrammed resource acquisition, central carbon and energy metabolisms. Ecologically, this work suggests that one cell, infected versus uninfected, can have immensely different metabolisms that affect the ecosystem differently. Finally, we relate phage–host genome complementarity, virocell metabolic reprogramming, and viral fitness in a conceptual model to guide incorporating viruses into ecosystem models.
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Affiliation(s)
- Cristina Howard-Varona
- Department of Microbiology, The Ohio State University, 484 W 12th Ave, Columbus, OH, 43210, USA
| | - Morgan M Lindback
- Department of Ecology and Evolutionary Biology, University of Michigan, 1105 North University Ave, Ann Arbor, MI, 48109, USA
| | - G Eric Bastien
- Department of Ecology and Evolutionary Biology, University of Michigan, 1105 North University Ave, Ann Arbor, MI, 48109, USA
| | - Natalie Solonenko
- Department of Microbiology, The Ohio State University, 484 W 12th Ave, Columbus, OH, 43210, USA
| | - Ahmed A Zayed
- Department of Microbiology, The Ohio State University, 484 W 12th Ave, Columbus, OH, 43210, USA
| | - HoBin Jang
- Department of Microbiology, The Ohio State University, 484 W 12th Ave, Columbus, OH, 43210, USA
| | - Bill Andreopoulos
- US Department of Energy Joint Genome Institute, 1800 Mitchell Dr #100, Walnut Creek, CA, 94598, USA
| | - Heather M Brewer
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory (PNNL), 902 Battelle Blvd, Richland, WA, 99354, USA
| | - Tijana Glavina Del Rio
- US Department of Energy Joint Genome Institute, 1800 Mitchell Dr #100, Walnut Creek, CA, 94598, USA
| | - Joshua N Adkins
- Biological Science Division, PNNL, 902 Battelle Blvd, Richland, WA, 99354, USA
| | - Subhadeep Paul
- Department of Statistics, The Ohio State University, 1958 Neil Ave, Columbus, OH, 43210, USA
| | - Matthew B Sullivan
- Department of Microbiology, The Ohio State University, 484 W 12th Ave, Columbus, OH, 43210, USA. .,Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, 2070 Neil Ave, Columbus, OH, 43210, USA. .,Center for RNA Biology, The Ohio State University, 484 W. 12th Ave, Columbus, OH, 43210, USA.
| | - Melissa B Duhaime
- Department of Ecology and Evolutionary Biology, University of Michigan, 1105 North University Ave, Ann Arbor, MI, 48109, USA.
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47
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Mende DR, Boeuf D, DeLong EF. Persistent Core Populations Shape the Microbiome Throughout the Water Column in the North Pacific Subtropical Gyre. Front Microbiol 2019; 10:2273. [PMID: 31632377 PMCID: PMC6779783 DOI: 10.3389/fmicb.2019.02273] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 09/18/2019] [Indexed: 01/23/2023] Open
Abstract
Marine microbial communities are responsible for many important ecosystem processes in the oceans. Their variability across time and depths is well recognized, but mostly at a coarse-grained taxonomic resolution. To gain a deeper perspective on ecological patterns of bacterioplankton diversity in the North Pacific Subtropical Gyre, we characterized bacterioplankton communities throughout the water column at a fine-grained taxonomic level with a focus on temporally persistent (core) populations. Considerable intra-clade microdiversity was evident in virtually every microbial clade examined. While some of the most abundant populations comprised only a small fraction of the intra-clade microdiversity, they formed a temporally persistent core within a more diverse array of less abundant ephemeral populations. The depth-stratified population structure within many phylogenetically disparate clades suggested that ecotypic variation was the rule among most planktonic bacterial and archaeal lineages. Our results suggested that the abundant, persistent core populations comprised the bulk of the biomass within any given clade. As such, we postulate that these core populations are largely responsible for microbially driven ecosystem processes, and so represent ideal targets for elucidating key microbial processes in the open-ocean water column.
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Affiliation(s)
- Daniel R Mende
- Daniel K. Inouye Center for Microbial Oceanography, Research and Education, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, Honolulu, HI, United States
| | - Dominique Boeuf
- Daniel K. Inouye Center for Microbial Oceanography, Research and Education, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, Honolulu, HI, United States
| | - Edward F DeLong
- Daniel K. Inouye Center for Microbial Oceanography, Research and Education, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, Honolulu, HI, United States
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48
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Xaxiri NA, Nikouli E, Berillis P, Kormas KA. Bacterial biofilm development during experimental degradation of Melicertus kerathurus exoskeleton in seawater. AIMS Microbiol 2019; 4:397-412. [PMID: 31294223 PMCID: PMC6604942 DOI: 10.3934/microbiol.2018.3.397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Accepted: 05/29/2018] [Indexed: 11/28/2022] Open
Abstract
Chitinolytic bacteria are widespread in marine and terrestrial environment, and this is rather a reflection of their principle growth substrate's ubiquity, chitin, in our planet. In this paper, we investigated the development of naturally occurring bacterial biofilms on the exoskeleton of the shrimp Melicertus kerathurus during its degradation in sea water. During a 12-day experiment with exoskeleton fragments in batch cultures containing only sea water as the growth medium at 18 °C in darkness, we analysed the formation and succession of biofilms by scanning electron microscopy and 16S rRNA gene diversity by next generation sequencing. Bacteria belonging to the γ- and α-Proteobacteria and Bacteroidetes showed marked (less or more than 10%) changes in their relative abundance from the beginning of the experiment. These bacterial taxa related to known chitinolytic bacteria were the Pseudolateromonas porphyrae, Halomonasaquamarina, Reinekea aestuarii, Colwellia asteriadis and Vibrio crassostreae. These bacteria could be considered as appropriate candidates for the degradation of chitinous crustacean waste from the seafood industry as they dominated in the biofilms developed on the shrimp's exoskeleton in natural sea water with no added substrates and the degradation of the shrimp exoskeleton was also evidenced.
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Affiliation(s)
- Nikolina-Alexandra Xaxiri
- Department of Ichthyology & Aquatic Environment, School of Agricultural Sciences, University of Thessaly, 38446 Volos, Greece
| | - Eleni Nikouli
- Department of Ichthyology & Aquatic Environment, School of Agricultural Sciences, University of Thessaly, 38446 Volos, Greece
| | - Panagiotis Berillis
- Department of Ichthyology & Aquatic Environment, School of Agricultural Sciences, University of Thessaly, 38446 Volos, Greece
| | - Konstantinos Ar Kormas
- Department of Ichthyology & Aquatic Environment, School of Agricultural Sciences, University of Thessaly, 38446 Volos, Greece
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49
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Wright RJ, Gibson MI, Christie-Oleza JA. Understanding microbial community dynamics to improve optimal microbiome selection. MICROBIOME 2019; 7:85. [PMID: 31159875 PMCID: PMC6547603 DOI: 10.1186/s40168-019-0702-x] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 05/21/2019] [Indexed: 05/20/2023]
Abstract
BACKGROUND Artificial selection of microbial communities that perform better at a desired process has seduced scientists for over a decade, but the method has not been systematically optimised nor the mechanisms behind its success, or failure, determined. Microbial communities are highly dynamic and, hence, go through distinct and rapid stages of community succession, but the consequent effect this may have on artificially selected communities is unknown. RESULTS Using chitin as a case study, we successfully selected for microbial communities with enhanced chitinase activities but found that continuous optimisation of incubation times between selective transfers was of utmost importance. The analysis of the community composition over the entire selection process revealed fundamental aspects in microbial ecology: when incubation times between transfers were optimal, the system was dominated by Gammaproteobacteria (i.e. main bearers of chitinase enzymes and drivers of chitin degradation), before being succeeded by cheating, cross-feeding and grazing organisms. CONCLUSIONS The selection of microbiomes to enhance a desired process is widely used, though the success of artificially selecting microbial communities appears to require optimal incubation times in order to avoid the loss of the desired trait as a consequence of an inevitable community succession. A comprehensive understanding of microbial community dynamics will improve the success of future community selection studies.
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Affiliation(s)
- Robyn J. Wright
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Matthew I. Gibson
- Department of Chemistry, University of Warwick, Coventry, UK
- Medical School, University of Warwick, Coventry, UK
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50
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Duret MT, Lampitt RS, Lam P. Prokaryotic niche partitioning between suspended and sinking marine particles. ENVIRONMENTAL MICROBIOLOGY REPORTS 2019; 11:386-400. [PMID: 30246414 DOI: 10.1111/1758-2229.12692] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 09/12/2018] [Indexed: 06/08/2023]
Abstract
Suspended particles are major organic carbon substrates for heterotrophic microorganisms in the mesopelagic ocean (100-1000 m). Nonetheless, communities associated with these particles have been overlooked compared with sinking particles, the latter generally considered as main carbon transporters to the deep ocean. This study is the first to differentiate prokaryotic communities associated with suspended and sinking particles, collected with a marine snow catcher at four environmentally distinct stations in the Scotia Sea. Amplicon sequencing of 16S rRNA gene revealed distinct prokaryotic communities associated with the two particle-types in the mixed-layer (0-100 m) and upper-mesopelagic zone (mean dissimilarity 42.5% ± 15.2%). Although common remineralising taxa were present within both particle-types, gammaproteobacterial Pseudomonadales and Vibrionales, and alphaproteobacterial Rhodobacterales were found enriched in sinking particles up to 32-fold, while Flavobacteriales (Bacteroidetes) favoured suspended particles. We propose that this niche-partitioning may be driven by organic matter properties found within both particle-types: K-strategists, specialised in the degradation of complex organic compounds, thrived on semi-labile suspended particles, while generalists r-strategists were adapted to the transient labile organic contents of sinking particles. Differences between the two particle-associated communities were more pronounced in the mesopelagic than in the surface ocean, likely resulting from exchanges between particle-pools enabled by the stronger turbulence.
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Affiliation(s)
- Manon T Duret
- Ocean and Earth Science, University of Southampton, Southampton, UK
| | | | - Phyllis Lam
- Ocean and Earth Science, University of Southampton, Southampton, UK
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