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Balmonte JP, Giebel HA, Arnosti C, Simon M, Wietz M. Distinct bacterial succession and functional response to alginate in the South, Equatorial, and North Pacific Ocean. Environ Microbiol 2024; 26:e16594. [PMID: 38418376 DOI: 10.1111/1462-2920.16594] [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: 05/04/2023] [Accepted: 01/26/2024] [Indexed: 03/01/2024]
Abstract
The availability of alginate, an abundant macroalgal polysaccharide, induces compositional and functional responses among marine microbes, but these dynamics have not been characterized across the Pacific Ocean. We investigated alginate-induced compositional and functional shifts (e.g., heterotrophic production, glucose turnover, hydrolytic enzyme activities) of microbial communities in the South Subtropical, Equatorial, and Polar Frontal North Pacific in mesocosms. We observed that shifts in response to alginate were site-specific. In the South Subtropical Pacific, prokaryotic cell counts, glucose turnover, and peptidase activities changed the most with alginate addition, along with the enrichment of the widest range of particle-associated taxa (161 amplicon sequence variants; ASVs) belonging to Alteromonadaceae, Rhodobacteraceae, Phormidiaceae, and Pseudoalteromonadaceae. Some of these taxa were detected at other sites but only enriched in the South Pacific. In the Equatorial Pacific, glucose turnover and heterotrophic prokaryotic production increased most rapidly; a single Alteromonas taxon dominated (60% of the community) but remained low (<2%) elsewhere. In the North Pacific, the particle-associated community response to alginate was gradual, with a more limited range of alginate-enriched taxa (82 ASVs). Thus, alginate-related ecological and biogeochemical shifts depend on a combination of factors that include the ability to utilize alginate, environmental conditions, and microbial interactions.
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Affiliation(s)
- John Paul Balmonte
- Department of Earth, Marine and Environmental Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Department of Earth and Environmental Sciences, Lehigh University, Bethlehem, PA, USA
| | - Helge-Ansgar Giebel
- Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, Germany
| | - Carol Arnosti
- Department of Earth, Marine and Environmental Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Meinhard Simon
- Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, Germany
| | - Matthias Wietz
- Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Oldenburg, Germany
- Deep-Sea Ecology and Technology, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
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Brown S, Lloyd CC, Giljan G, Ghobrial S, Amann R, Arnosti C. Pulsed inputs of high molecular weight organic matter shift the mechanisms of substrate utilisation in marine bacterial communities. Environ Microbiol 2024; 26:e16580. [PMID: 38254313 DOI: 10.1111/1462-2920.16580] [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: 07/06/2023] [Accepted: 12/27/2023] [Indexed: 01/24/2024]
Abstract
Heterotrophic bacteria hydrolyze high molecular weight (HMW) organic matter extracellularly prior to uptake, resulting in diffusive loss of hydrolysis products. An alternative 'selfish' uptake mechanism that minimises this loss has recently been found to be common in the ocean. We investigated how HMW organic matter addition affects these two processing mechanisms in surface and bottom waters at three stations in the North Atlantic Ocean. A pulse of HMW organic matter increased cell numbers, as well as the rate and spectrum of extracellular enzymatic activities at both depths. The effects on selfish uptake were more differentiated: in Gulf Stream surface waters and productive surface waters south of Newfoundland, selfish uptake of structurally simple polysaccharides increased upon HMW organic matter addition. The number of selfish bacteria taking up structurally complex polysaccharides, however, was largely unchanged. In contrast, in the oligotrophic North Atlantic gyre, despite high external hydrolysis rates, the number of selfish bacteria was unchanged, irrespective of polysaccharide structure. In deep bottom waters (> 4000 m), structurally complex substrates were processed only by selfish bacteria. Mechanisms of substrate processing-and the extent to which hydrolysis products are released to the external environment-depend on substrate structural complexity and the resident bacterial community.
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Affiliation(s)
- Sarah Brown
- Environment, Ecology, and Energy Program, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina, USA
| | - C Chad Lloyd
- Department of Earth, Marine and Environmental Sciences, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina, USA
| | - Greta Giljan
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Sherif Ghobrial
- Department of Earth, Marine and Environmental Sciences, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina, USA
| | - Rudolf Amann
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Carol Arnosti
- Department of Earth, Marine and Environmental Sciences, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
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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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Predictable Changes in Eelgrass Microbiomes with Increasing Wasting Disease Prevalence across 23° Latitude in the Northeastern Pacific. mSystems 2022; 7:e0022422. [PMID: 35856664 PMCID: PMC9426469 DOI: 10.1128/msystems.00224-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Predicting outcomes of marine disease outbreaks presents a challenge in the face of both global and local stressors. Host-associated microbiomes may play important roles in disease dynamics but remain understudied in marine ecosystems. Host–pathogen–microbiome interactions can vary across host ranges, gradients of disease, and temperature; studying these relationships may aid our ability to forecast disease dynamics. Eelgrass, Zostera marina, is impacted by outbreaks of wasting disease caused by the opportunistic pathogen Labyrinthula zosterae. We investigated how Z. marina phyllosphere microbial communities vary with rising wasting disease lesion prevalence and severity relative to plant and meadow characteristics like shoot density, longest leaf length, and temperature across 23° latitude in the Northeastern Pacific. We detected effects of geography (11%) and smaller, but distinct, effects of temperature (30-day max sea surface temperature, 4%) and disease (lesion prevalence, 3%) on microbiome composition. Declines in alpha diversity on asymptomatic tissue occurred with rising wasting disease prevalence within meadows. However, no change in microbiome variability (dispersion) was detected between asymptomatic and symptomatic tissues. Further, we identified members of Cellvibrionaceae, Colwelliaceae, and Granulosicoccaceae on asymptomatic tissue that are predictive of wasting disease prevalence across the geographic range (3,100 kilometers). Functional roles of Colwelliaceae and Granulosicoccaceae are not known. Cellvibrionaceae, degraders of plant cellulose, were also enriched in lesions and adjacent green tissue relative to nonlesioned leaves. Cellvibrionaceae may play important roles in disease progression by degrading host tissues or overwhelming plant immune responses. Thus, inclusion of microbiomes in wasting disease studies may improve our ability to understand variable rates of infection, disease progression, and plant survival. IMPORTANCE The roles of marine microbiomes in disease remain poorly understood due, in part, to the challenging nature of sampling at appropriate spatiotemporal scales and across natural gradients of disease throughout host ranges. This is especially true for marine vascular plants like eelgrass (Zostera marina) that are vital for ecosystem function and biodiversity but are susceptible to rapid decline and die-off from pathogens like eukaryotic slime-mold Labyrinthula zosterae (wasting disease). We link bacterial members of phyllosphere tissues to the prevalence of wasting disease across the broadest geographic range to date for a marine plant microbiome-disease study (3,100 km). We identify Cellvibrionaceae, plant cell wall degraders, enriched (up to 61% relative abundance) within lesion tissue, which suggests this group may be playing important roles in disease progression. These findings suggest inclusion of microbiomes in marine disease studies will improve our ability to predict ecological outcomes of infection across variable landscapes spanning thousands of kilometers.
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Liu S, Longnecker K, Kujawinski EB, Vergin K, Bolaños LM, Giovannoni SJ, Parsons R, Opalk K, Halewood E, Hansell DA, Johnson R, Curry R, Carlson CA. Linkages Among Dissolved Organic Matter Export, Dissolved Metabolites, and Associated Microbial Community Structure Response in the Northwestern Sargasso Sea on a Seasonal Scale. Front Microbiol 2022; 13:833252. [PMID: 35350629 PMCID: PMC8957919 DOI: 10.3389/fmicb.2022.833252] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 01/31/2022] [Indexed: 01/04/2023] Open
Abstract
Deep convective mixing of dissolved and suspended organic matter from the surface to depth can represent an important export pathway of the biological carbon pump. The seasonally oligotrophic Sargasso Sea experiences annual winter convective mixing to as deep as 300 m, providing a unique model system to examine dissolved organic matter (DOM) export and its subsequent compositional transformation by microbial oxidation. We analyzed biogeochemical and microbial parameters collected from the northwestern Sargasso Sea, including bulk dissolved organic carbon (DOC), total dissolved amino acids (TDAA), dissolved metabolites, bacterial abundance and production, and bacterial community structure, to assess the fate and compositional transformation of DOM by microbes on a seasonal time-scale in 2016–2017. DOM dynamics at the Bermuda Atlantic Time-series Study site followed a general annual trend of DOC accumulation in the surface during stratified periods followed by downward flux during winter convective mixing. Changes in the amino acid concentrations and compositions provide useful indices of diagenetic alteration of DOM. TDAA concentrations and degradation indices increased in the mesopelagic zone during mixing, indicating the export of a relatively less diagenetically altered (i.e., more labile) DOM. During periods of deep mixing, a unique subset of dissolved metabolites, such as amino acids, vitamins, and benzoic acids, was produced or lost. DOM export and compositional change were accompanied by mesopelagic bacterial growth and response of specific bacterial lineages in the SAR11, SAR202, and SAR86 clades, Acidimicrobiales, and Flavobacteria, during and shortly following deep mixing. Complementary DOM biogeochemistry and microbial measurements revealed seasonal changes in DOM composition and diagenetic state, highlighting microbial alteration of the quantity and quality of DOM in the ocean.
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Affiliation(s)
- Shuting Liu
- Department of Ecology, Evolution and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Krista Longnecker
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
| | - Elizabeth B Kujawinski
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
| | - Kevin Vergin
- Microbial DNA Analytics, Phoenix, OR, United States
| | - Luis M Bolaños
- School of Biosciences, University of Exeter, Exeter, United Kingdom.,Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | - Stephen J Giovannoni
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | - Rachel Parsons
- Bermuda Institute of Ocean Sciences, Saint George's, Bermuda
| | - Keri Opalk
- Department of Ecology, Evolution and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Elisa Halewood
- Department of Ecology, Evolution and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Dennis A Hansell
- Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, United States
| | - Rod Johnson
- Bermuda Institute of Ocean Sciences, Saint George's, Bermuda
| | - Ruth Curry
- Bermuda Institute of Ocean Sciences, Saint George's, Bermuda
| | - Craig A Carlson
- Department of Ecology, Evolution and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
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Hou J, Guo Z, Meng F, Li M, Hou LA. Restoration of organic-matter-impoverished arable soils through the application of soil conditioner prepared via short-time hydrothermal fermentation. ENVIRONMENTAL RESEARCH 2022; 204:112088. [PMID: 34563527 DOI: 10.1016/j.envres.2021.112088] [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: 05/25/2021] [Revised: 09/09/2021] [Accepted: 09/17/2021] [Indexed: 06/13/2023]
Abstract
The diversity and stability of critical microbial communities are of great importance for ensuring soil fertility. From the perspective of stimulating microbial diversity in organic-matter-impoverished arable soils, soil conditioner with a certain proportion of labile organic carbon was prepared by short-time hydrothermal fermentation (SHF). The effects of applying SHF, along with soil conditioner derived from traditional aerobic fermentation (TF) and heterogeneous fertilizer (HF), on soil texture, dissolved organic matter evolution, the structure of humic acid, and the succession of dominant microbial taxa were evaluated. SHF enhanced the storage capacity of soil organic carbon and nitrogen retention, and increased the relative abundance of Proteobacteria, Firmicutes and Nitrospirae in organic-matter-impoverished arable soil, with Lysobacter as its significant difference species. In conclusion, the proposed soil conditioner and the positive effects observed in this study indicate that it could be used to solve dual problems of food waste recycling and arable soil improvement.
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Affiliation(s)
- Jiaqi Hou
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Beijing, 100012, China
| | - Zhiying Guo
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Fanhua Meng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Beijing, 100012, China
| | - Mingxiao Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Beijing, 100012, China.
| | - Li-An Hou
- Xi'an High-Tech Institute, Xi'an, 710025, China
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7
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Thomas F, Le Duff N, Wu TD, Cébron A, Uroz S, Riera P, Leroux C, Tanguy G, Legeay E, Guerquin-Kern JL. Isotopic tracing reveals single-cell assimilation of a macroalgal polysaccharide by a few marine Flavobacteria and Gammaproteobacteria. THE ISME JOURNAL 2021; 15:3062-3075. [PMID: 33953365 PMCID: PMC8443679 DOI: 10.1038/s41396-021-00987-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 03/25/2021] [Accepted: 04/09/2021] [Indexed: 02/03/2023]
Abstract
Algal polysaccharides constitute a diverse and abundant reservoir of organic matter for marine heterotrophic bacteria, central to the oceanic carbon cycle. We investigated the uptake of alginate, a major brown macroalgal polysaccharide, by microbial communities from kelp-dominated coastal habitats. Congruent with cell growth and rapid substrate utilization, alginate amendments induced a decrease in bacterial diversity and a marked compositional shift towards copiotrophic bacteria. We traced 13C derived from alginate into specific bacterial incorporators and quantified the uptake activity at the single-cell level, using halogen in situ hybridization coupled to nanoscale secondary ion mass spectrometry (HISH-SIMS) and DNA stable isotope probing (DNA-SIP). Cell-specific alginate uptake was observed for Gammaproteobacteria and Flavobacteriales, with carbon assimilation rates ranging from 0.14 to 27.50 fg C µm-3 h-1. DNA-SIP revealed that only a few initially rare Flavobacteriaceae and Alteromonadales taxa incorporated 13C from alginate into their biomass, accounting for most of the carbon assimilation based on bulk isotopic measurements. Functional screening of metagenomic libraries gave insights into the genes of alginolytic Alteromonadales active in situ. These results highlight the high degree of niche specialization in heterotrophic communities and help constraining the quantitative role of polysaccharide-degrading bacteria in coastal ecosystems.
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Affiliation(s)
- François Thomas
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR), Roscoff, France.
| | - Nolwen Le Duff
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR), Roscoff, France
| | - Ting-Di Wu
- Institut Curie, Université Paris-Saclay, Paris, France
- Université Paris-Saclay, INSERM US43, CNRS UMS2016, Multimodal Imaging Center, Orsay, France
| | | | - Stéphane Uroz
- Université de Lorraine, INRAE, UMR1136 « Interactions Arbres-Microorganismes », Champenoux, France
| | - Pascal Riera
- Sorbonne Université, CNRS, UMR7144, Station Biologique de Roscoff (SBR), Roscoff, France
| | - Cédric Leroux
- CNRS, Sorbonne Université, FR2424, Metabomer, Station Biologique de Roscoff, Roscoff, France
| | - Gwenn Tanguy
- CNRS, Sorbonne Université, FR2424, Genomer, Station Biologique de Roscoff, Roscoff, France
| | - Erwan Legeay
- CNRS, Sorbonne Université, FR2424, Genomer, Station Biologique de Roscoff, Roscoff, France
| | - Jean-Luc Guerquin-Kern
- Institut Curie, Université Paris-Saclay, Paris, France
- Université Paris-Saclay, INSERM US43, CNRS UMS2016, Multimodal Imaging Center, Orsay, France
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Li M, Fang A, Yu X, Zhang K, He Z, Wang C, Peng Y, Xiao F, Yang T, Zhang W, Zheng X, Zhong Q, Liu X, Yan Q. Microbially-driven sulfur cycling microbial communities in different mangrove sediments. CHEMOSPHERE 2021; 273:128597. [PMID: 33077194 DOI: 10.1016/j.chemosphere.2020.128597] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/05/2020] [Accepted: 10/07/2020] [Indexed: 05/13/2023]
Abstract
Microbially-driven sulfur cycling is a vital biogeochemical process in the sulfur-rich mangrove ecosystem. It is critical to evaluate the potential impact of sulfur transformation in mangrove ecosystems. To reveal the diversity, composition, and structure of sulfur-oxidizing bacteria (SOB) and sulfate-reducing bacteria (SRB) and underlying mechanisms, we analyzed the physicochemical properties and sediment microbial communities from an introduced mangrove species (Sonneratia apetala), a native mangrove species (Kandelia obovata) and the mudflat in Hanjiang River Estuary in Guangdong (23.27°N, 116.52°E), China. The results indicated that SOB was dominated by autotrophic Thiohalophilus and chemoautotrophy Chromatium in S. apetala and K. obovata, respectively, while Desulfatibacillum was the dominant genus of SRB in K. obovata sediments. Also, the redundancy analysis indicated that temperature, redox potential (ORP), and SO42- were the significant factors influencing the sulfur cycling microbial communities with elemental sulfur (ES) as the key factor driver for SOB and total carbon (TC) for SRB in mangrove sediments. Additionally, the morphological transformation of ES, acid volatile sulfide (AVS) and SO42- explained the variation of sulfur cycling microbial communities under sulfur-rich conditions, and we found mangrove species-specific dominant Thiohalobacter, Chromatium and Desulfatibacillum, which could well use ES and SO42-, thus promoting the sulfur cycling in mangrove sediments. Meanwhile, the change of nutrient substances (TN, TC) explained why SOB were more susceptible to environmental changes than SRB. Sulfate reducing bacteria produces sulfide in anoxic sediments at depth that then migrate upward, toward fewer reducing conditions, where it's oxidized by sulfur oxidizing bacteria. This study indicates the high ability of SOB and SRB in ES, SO42-,S2- and S2- generation and transformation in sulfur-rich mangrove ecosystems, and provides novel insights into sulfur cycling in other wetland ecosystems from a microbial perspective.
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Affiliation(s)
- Mingyue Li
- 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
| | - Anqi Fang
- 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
| | - Xiaoli Yu
- 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
| | - Keke Zhang
- 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
| | - 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; College of Agronomy, Hunan Agricultural University, Changsha, 410128, 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
| | - Yisheng Peng
- 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
| | - Fanshu Xiao
- 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.
| | - Tony Yang
- 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
| | - Wei Zhang
- 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
| | - Xiafei Zheng
- 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
| | - Qiuping Zhong
- 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
| | - Xingyu 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
| | - Qingyun Yan
- 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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9
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Sjöstedt J, Lapierre JF, Yamashita Y, Baltar F. Editorial: Microbial Utilization and Transformation of Dissolved Organic Matter in Aquatic Environments-From Streams to the Deep Ocean. Front Microbiol 2021; 12:668560. [PMID: 34054777 PMCID: PMC8155277 DOI: 10.3389/fmicb.2021.668560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 04/06/2021] [Indexed: 11/13/2022] Open
Affiliation(s)
- Johanna Sjöstedt
- Department of Biology, Aquatic Ecology, Lund University, Lund, Sweden
| | | | - Youhei Yamashita
- Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Japan
| | - Federico Baltar
- Department of Functional and Evolutionary Ecology, University of Vienna, Vienna, Austria
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Jain A, Krishnan KP. Marine Group-II archaea dominate particle-attached as well as free-living archaeal assemblages in the surface waters of Kongsfjorden, Svalbard, Arctic Ocean. Antonie van Leeuwenhoek 2021; 114:633-647. [PMID: 33694023 PMCID: PMC7945612 DOI: 10.1007/s10482-021-01547-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 02/16/2021] [Indexed: 01/23/2023]
Abstract
Marine archaea are a significant component of the global oceanic ecosystems, including the polar oceans. However, only a few attempts have been made to study archaea in the high Arctic fjords. Given the importance of Archaea in carbon and nitrogen cycling, it is imperative to explore their diversity and community composition in the high Arctic fjords, such as Kongsfjorden (Svalbard). In the present study, we evaluated archaeal diversity and community composition in the size-fractionated microbial population, viz-a-viz free-living (FL; 0.2-3 μm) and particle-attached (PA; > 3 μm) using archaeal V3-V4 16S rRNA gene amplicon sequencing. Our results indicate that the overall archaeal community in the surface water of Kongsfjorden was dominated by the members of the marine group-II (MGII) archaea, followed by the MGI group members, including Nitrosopumilaceae and Nitrososphaeraceae. Although a clear niche partitioning between PA and FL archaeal communities was not observed, 2 OTUs among 682 OTUs, and 3 ASVs out of 1932 ASVs were differentially abundant among the fractions. OTU001/ASV0002, classified as MGIIa, was differentially abundant in the PA fraction. OTU006/ASV0006/ASV0010 affiliated with MGIIb were differentially abundant in the FL fraction. Particulate organic nitrogen and C:N ratio were the most significant variables (P < 0.05) explaining the observed variation in the FL and PA archaeal communities, respectively. These results indicate an exchange between archaeal communities or a generalist lifestyle switching between FL and PA fractions. Besides, the particles' elemental composition (carbon and nitrogen) seems to play an essential role in shaping the PA archaeal communities in the surface waters of Kongsfjorden.
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Affiliation(s)
- Anand Jain
- Arctic Division, National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Vasco-da-Gama, Goa, India.
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11
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Brunet M, de Bettignies F, Le Duff N, Tanguy G, Davoult D, Leblanc C, Gobet A, Thomas F. Accumulation of detached kelp biomass in a subtidal temperate coastal ecosystem induces succession of epiphytic and sediment bacterial communities. Environ Microbiol 2021; 23:1638-1655. [PMID: 33400326 PMCID: PMC8248336 DOI: 10.1111/1462-2920.15389] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 12/14/2020] [Accepted: 01/02/2021] [Indexed: 12/30/2022]
Abstract
Kelps are dominant primary producers in temperate coastal ecosystems. Large amounts of kelp biomass can be exported to the seafloor during the algal growth cycle or following storms, creating new ecological niches for the associated microbiota. Here, we investigated the bacterial community associated with the kelp Laminaria hyperborea during its accumulation and degradation on the seafloor. Kelp tissue, seawater and sediment were sampled during a 6-month in situ experiment simulating kelp detritus accumulation. Evaluation of the epiphytic bacterial community abundance, structure, taxonomic composition and predicted functional profiles evidenced a biphasic succession. Initially, dominant genera (Hellea, Litorimonas, Granulosicoccus) showed a rapid and drastic decrease in sequence abundance, probably outcompeted by algal polysaccharide-degraders such as Bacteroidia members which responded within 4 weeks. Acidimicrobiia, especially members of the Sva0996 marine group, colonized the degrading kelp biomass after 11 weeks. These secondary colonizers could act as opportunistic scavenger bacteria assimilating substrates exposed by early degraders. In parallel, kelp accumulation modified bacterial communities in the underlying sediment, notably favouring anaerobic taxa potentially involved in the sulfur and nitrogen cycles. Overall, this study provides insights into the bacterial degradation of algal biomass in situ, an important link in coastal trophic chains.
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Affiliation(s)
- Maéva Brunet
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR)Roscoff29680France
| | - Florian de Bettignies
- Sorbonne Université, CNRS, UMR 7144 AD2M, Station Biologique de Roscoff (SBR)Roscoff29680France
| | - Nolwen Le Duff
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR)Roscoff29680France
| | - Gwenn Tanguy
- Sorbonne Université, CNRS, FR2424, Genomer, Station Biologique de RoscoffRoscoff29680France
| | - Dominique Davoult
- Sorbonne Université, CNRS, UMR 7144 AD2M, Station Biologique de Roscoff (SBR)Roscoff29680France
| | - Catherine Leblanc
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR)Roscoff29680France
| | - Angélique Gobet
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR)Roscoff29680France
- MARBEC, Univ Montpellier, CNRS, Ifremer, IRDSèteFrance
| | - François Thomas
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR)Roscoff29680France
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12
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Abstract
Organic matter in the global ocean, soils, and sediments stores about five times more carbon than the atmosphere. Thus, the controls on the accumulation of organic matter are critical to global carbon cycling. However, we lack a quantitative understanding of these controls. This prevents meaningful descriptions of organic matter cycling in global climate models, which are required for understanding how changes in organic matter reservoirs provide feedbacks to past and present changes in climate. Currently, explanations for organic matter accumulation remain under debate, characterized by seemingly competing hypotheses. Here, we develop a quantitative framework for organic matter accumulation that unifies these hypotheses. The framework derives from the ecological dynamics of microorganisms, the dominant consumers of organic matter. Organic matter constitutes a key reservoir in global elemental cycles. However, our understanding of the dynamics of organic matter and its accumulation remains incomplete. Seemingly disparate hypotheses have been proposed to explain organic matter accumulation: the slow degradation of intrinsically recalcitrant substrates, the depletion to concentrations that inhibit microbial consumption, and a dependency on the consumption capabilities of nearby microbial populations. Here, using a mechanistic model, we develop a theoretical framework that explains how organic matter predictably accumulates in natural environments due to biochemical, ecological, and environmental factors. Our framework subsumes the previous hypotheses. Changes in the microbial community or the environment can move a class of organic matter from a state of functional recalcitrance to a state of depletion by microbial consumers. The model explains the vertical profile of dissolved organic carbon in the ocean and connects microbial activity at subannual timescales to organic matter turnover at millennial timescales. The threshold behavior of the model implies that organic matter accumulation may respond nonlinearly to changes in temperature and other factors, providing hypotheses for the observed correlations between organic carbon reservoirs and temperature in past earth climates.
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13
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Yang C, Sun J, Chen Y, Wu J, Wang Y. Linkage between water soluble organic matter and bacterial community in sediment from a shallow, eutrophic lake, Lake Chaohu, China. J Environ Sci (China) 2020; 98:39-46. [PMID: 33097156 DOI: 10.1016/j.jes.2020.05.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 05/21/2020] [Accepted: 05/21/2020] [Indexed: 06/11/2023]
Abstract
Lacustrine sediment played important roles in migration and transformation of its water soluble organic matter (WSOM), and the source and composition of WSOM would affect water trophic status and the fate of pollutants. However, we know little about the pathway of WSOM transformation and its driving bacterial communities in lacustrine sediment. In the present study, we investigated the spatial distribution patterns of sediment WSOM and its fluorescent fractions across Lake Chaohu using fluorescence spectroscopy, and explored WSOM compositional structure through our proposed calculated ratios. In addition, we also analyzed sediment bacterial community using Illumina sequencing technology, and probed the possible pathway of sediment WSOM transformation under the mediate of indigenous bacteria. Our results showed that the inflowing rivers affected the spatial distribution patterns of WSOM and its five fractions (including tyrosine-, tryptophan-, fulvic acid-, humic acid-like substances and soluble microbial productions), and sediment WSOM originated from fresh algae detritus or bacterial sources. In parallel, we also found that Proteobacteria (mainly γ-Proteobacteria and δ-Proteobacteria), Firmicutes (mainly Bacilli), Chloroflexi, Acidobacteria, Planctomycetes and Actinobacteria dominate sediment bacterial community. Furthermore, these dominant bacteria triggered sediment WSOM transformation, specifically, the humic acid-like substances could be converted into fulvic acid-like substances, and further degraded into aromatic protein-like and SMP substances. In addition, our proposed ratios (P-L:H-L, Ar-P:SMP and H-L ratio), as supplementary tool, were effective to reveal WSOM composition structure. These results figured out possible pathway of WSOM transformation, and revealed its microbial mechanism in lacustrine sediment.
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Affiliation(s)
- Changming Yang
- Key Laboratory of Yangtze River Water Environment of the Ministry of Education, Tongji University, Shanghai 200092, China.
| | - Jiliang Sun
- Key Laboratory of Yangtze River Water Environment of the Ministry of Education, Tongji University, Shanghai 200092, China; Shanghai BaoSen Environmental Technology Co., Ltd., Shanghai 200439, China
| | - Yingying Chen
- School of Energy and Environment, Anhui University of Technology, Maanshan City 243002, China
| | - Jing Wu
- School of Energy and Environment, Anhui University of Technology, Maanshan City 243002, China
| | - Yulai Wang
- School of Energy and Environment, Anhui University of Technology, Maanshan City 243002, China.
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14
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Varela MM, Rodríguez-Ramos T, Guerrero-Feijóo E, Nieto-Cid M. Changes in Activity and Community Composition Shape Bacterial Responses to Size-Fractionated Marine DOM. Front Microbiol 2020; 11:586148. [PMID: 33329457 PMCID: PMC7714726 DOI: 10.3389/fmicb.2020.586148] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 09/30/2020] [Indexed: 12/21/2022] Open
Abstract
To study the response of bacteria to different size-fractions of naturally occurring dissolved organic matter (DOM), a natural prokaryotic community from North Atlantic mesopelagic waters (1000 m depth) was isolated and grown in (i) 0.1-μm filtered seawater (CONTROL), (ii) the low-molecular-weight (<1 kDa) DOM fraction (L-DOM), and (iii) the recombination of high- (>1 kDa) and low-molecular-weight DOM fractions (H + L-DOM), to test the potential effect of ultrafiltration on breaking the DOM size continuum. Prokaryotic abundance and leucine incorporation were consistently higher in the H + L-DOM niche than in the L-DOM and CONTROL treatments, suggesting a different interaction with each DOM fraction and the disruption of the structural DOM continuum by ultrafiltration, respectively. Rhodobacterales (Alphaproteobacteria) and Flavobacteriales (Bacteroidetes) were particularly enriched in L-DOM and closely related to the colored DOM (CDOM) fraction, indicating the tight link between these groups and changes in DOM aromaticity. Conversely, some other taxa that were rare or undetectable in the original bacterial community were enriched in the H + L-DOM treatment (e.g., Alteromonadales belonging to Gammaproteobacteria), highlighting the role of the rare biosphere as a seed bank of diversity against ecosystem disturbance. The relationship between the fluorescence of protein-like CDOM and community composition of populations in the H + L-DOM treatment suggested their preference for labile DOM. Conversely, the communities growing on the L-DOM niche were coupled to humic-like CDOM, which may indicate their ability to degrade more reworked DOM and/or the generation of refractory substrates (as by-products of the respiration processes). Most importantly, L- and/or H + L-DOM treatments stimulated the growth of unique bacterial amplicon sequence variants (ASVs), suggesting the potential of environmental selection (i.e., changes in DOM composition and availability), particularly in the light of climate change scenarios. Taken together, our results suggest that different size-fractions of DOM induced niche-specialization and differentiation of mesopelagic bacterial communities.
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Affiliation(s)
- Marta M Varela
- Centro Oceanográfico de A Coruña, Instituto Español de Oceanografía (IEO), A Coruña, Spain
| | - Tamara Rodríguez-Ramos
- Centro Oceanográfico de A Coruña, Instituto Español de Oceanografía (IEO), A Coruña, Spain
| | - Elisa Guerrero-Feijóo
- Centro Oceanográfico de A Coruña, Instituto Español de Oceanografía (IEO), A Coruña, Spain
| | - Mar Nieto-Cid
- Centro Oceanográfico de A Coruña, Instituto Español de Oceanografía (IEO), A Coruña, Spain.,Laboratorio de Geoquímica Orgánica, Instituto de Investigaciones Marinas (CSIC), Vigo, Spain
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15
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Yeh T, Krennmayr K, Liao C, Ejarque E, Schomakers J, Huang J, Zehetner F, Hein T. Effects of terrigenous organic substrates and additional phosphorus on bacterioplankton metabolism and exoenzyme stoichiometry. FRESHWATER BIOLOGY 2020; 65:1973-1988. [PMID: 33288968 PMCID: PMC7689783 DOI: 10.1111/fwb.13593] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 06/12/2020] [Accepted: 06/17/2020] [Indexed: 06/12/2023]
Abstract
Bamboo, as a pioneer vegetation, often forms forests on bare lands after catastrophic landslides. Compared to evergreen forest soil, bamboo forest soil is much more labile, with a higher percentage of microbially derived organic carbon (OC), lower molecular weight, and lower humic acid content. We hypothesised that different terrigenous organic matter (tOM) sources with varying lability and phosphorus (P) availability select for bacterioplankton with distinct metabolic pathways.We incubated natural bacterioplankton assemblages with tOM leached from bamboo forest soil (BOM) and evergreen forest soil (EOM) and compared these to a lake water control. To test if microbial metabolism would be limited by OC or P availability of each tOM treatment, we used acetate as an extra labile OC source and phosphate as an inorganic P source. Bacterial metabolism was measured by analysing respiration via O2 consumption and production via tritiated thymidine (TdR) assimilation.Bacterioplankton metabolism is limited by the availability of P in BOM substrates. When using BOM, bacteria had higher enzymatic activities for phosphatase. The nutrients required for bacterial biomass seemed to be derived from organic matter. Under BOM treatment, bacterial production (BP) (0.92 ± 0.13 μg C L-1 hr-1) and cell specific TdR assimilation rates (0.015 ± 0.002 10-18 M TdR cell-1 hr-1) were low. Adding P enhanced BP (BOM+P 1.52 ± 0.31 and BOM+C+P 2.25 ± 0.37 μg C L-1 hr-1) while acetate addition had no significant effect on BOM treatment.This indicated that the bacteria switched to using added inorganic P to respire a P-limited BOM substrate, which increased total BP and abundance, resulting in even more active respiration and lower growth efficiency. We also found higher activities for chitin-degrading enzyme β-N-acetylglucosaminidase, which is associated with N mining from aminosaccharides.Microbes using EOM, however, did not change metabolic strategies with additional acetate or/and inorganic P. This is due to higher concentrations of organic P in EOM substrates and the presence of inorganic N in the EOM leachates an alternative nutrient source. Bacteria produced β-glucosidase and leucyl-aminopeptidase in order to utilise the humic substances, which sustained greater bacterial abundance, higher BP (2.64 ± 0.39 μg C L-1 hr-1), and lower cell-specific respiration. This yielded a much higher bacterial growth efficiency (15 ± 9.2%) than the lake water control.Our study demonstrated the aquatic metabolic discrepancy between tOM of different forest types. Bacterioplankton in BOM and EOM exhibit distinct metabolic responses. Bacterial metabolic strategy when using BOM implied that the supposedly stabilised biomass OM might be efficiently used by aquatic bacterioplankton. As the labile and nutrient-deficient BOM is more susceptible to the influence of additional nutrients, fertiliser residues in bamboo forest catchments might have a stronger effect on aquatic bacterial metabolic pathways. Thus, it is important to take tOM differences into consideration when building models to estimate soil carbon turnover rates along a terrestrial-aquatic continuum.
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Affiliation(s)
- Tz‐Ching Yeh
- Institute of Hydrobiology and Aquatic Ecosystem ManagementUniversity of Natural Resources and Life Sciences (BOKU)ViennaAustria
- WasserCluster Lunz (WCL) Biological StationLunz am SeeAustria
| | - Kathrin Krennmayr
- Institute of Hydrobiology and Aquatic Ecosystem ManagementUniversity of Natural Resources and Life Sciences (BOKU)ViennaAustria
| | - Chien‐Sen Liao
- Department of Civil and Ecological EngineeringI‐Shou UniversityKaohsiungTaiwan
| | | | - Jasmin Schomakers
- Institute of Soil ResearchUniversity of Natural Resources and Life Sciences (BOKU)ViennaAustria
| | - Jr‐Chuan Huang
- Department of GeographyNational Taiwan University (NTU)TaipeiTaiwan
| | - Franz Zehetner
- Institute of Soil ResearchUniversity of Natural Resources and Life Sciences (BOKU)ViennaAustria
| | - Thomas Hein
- Institute of Hydrobiology and Aquatic Ecosystem ManagementUniversity of Natural Resources and Life Sciences (BOKU)ViennaAustria
- WasserCluster Lunz (WCL) Biological StationLunz am SeeAustria
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16
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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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17
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Reintjes G, Fuchs BM, Scharfe M, Wiltshire KH, Amann R, Arnosti C. Short-term changes in polysaccharide utilization mechanisms of marine bacterioplankton during a spring phytoplankton bloom. Environ Microbiol 2020; 22:1884-1900. [PMID: 32128969 DOI: 10.1111/1462-2920.14971] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 02/27/2020] [Accepted: 02/29/2020] [Indexed: 11/28/2022]
Abstract
Spring phytoplankton blooms in temperate environments contribute disproportionately to global marine productivity. Bloom-derived organic matter, much of it occurring as polysaccharides, fuels biogeochemical cycles driven by interacting autotrophic and heterotrophic communities. We tracked changes in the mode of polysaccharide utilization by heterotrophic bacteria during the course of a diatom-dominated bloom in the German Bight, North Sea. Polysaccharides can be taken up in a 'selfish' mode, where initial hydrolysis is coupled to transport into the periplasm, such that little to no low-molecular weight (LMW) products are externally released to the environment. Alternatively, polysaccharides hydrolyzed by cell-surface attached or free extracellular enzymes (external hydrolysis) yield LMW products available to the wider bacterioplankton community. In the early bloom phase, selfish activity was accompanied by low extracellular hydrolysis rates of a few polysaccharides. As the bloom progressed, selfish uptake increased markedly, and external hydrolysis rates increased, but only for a limited range of substrates. The late bloom phase was characterized by high external hydrolysis rates of a broad range of polysaccharides and reduced selfish uptake of polysaccharides, except for laminarin. Substrate utilization mode is related both to substrate structural complexity and to the bloom-stage dependent composition of the heterotrophic bacterial community.
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Affiliation(s)
- Greta Reintjes
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Bernhard M Fuchs
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | | | | | - Rudolf Amann
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Carol Arnosti
- Department of Marine Sciences, University of North Carolina-Chapel Hill, Chapel Hill, NC, USA
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18
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Jain A, Krishnan KP, Begum N, Singh A, Thomas FA, Gopinath A. Response of bacterial communities from Kongsfjorden (Svalbard, Arctic Ocean) to macroalgal polysaccharide amendments. MARINE ENVIRONMENTAL RESEARCH 2020; 155:104874. [PMID: 31975691 DOI: 10.1016/j.marenvres.2020.104874] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 01/06/2020] [Accepted: 01/07/2020] [Indexed: 06/10/2023]
Abstract
Macroalgae are abundant in coastal Arctic habitats and contain a large amount of polysaccharides. Increased macroalgal productivity due to warmer temperatures and reduced sea-ice cover contribute a significant amount of polysaccharide-rich detritus in the region. To study bacterial degradation of macroalgal polysaccharides and their potential impact on biogeochemical processes we studied the response of bacterial communities from Kongsfjorden, Svalbard (Arctic Ocean) to alginate (AL) and agarose (AG) amendments, using an ex-situ microcosm experiment. Our results show that bacterial communities responded to the increased availability of macroalgal polysaccharides and community shift was congruent with a significant decline in nutrient concentrations. Initially-rare bacterial taxa affiliated with Gammaproteobacteria and Bacteroidia responded to the polysaccharide addition. Each polysaccharide addition incited the growth of certain distinct bacteria taxa. Compared to the un-amended control microcosms (CM), Polaribacter, Colwellia, Pseudoalteromonas, and unclassified Gammaproteobacteria responded to AL addition, whereas Paraglaciecola, Lentimonas, Colwellia, unclassified Gammaproteobacteria, unclassified Alteromonadales, and unclassified Alteromonadaceae responded to the AG addition. These results suggest that polysaccharides shift bacterial community composition towards copiotrophic bacterial taxa, with implications for carbon and nutrient cycling in coastal Svalbard.
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Affiliation(s)
- Anand Jain
- Cryobiology Laboratory, National Centre for Polar and Ocean Research, Vasco da Gama, Goa, India.
| | | | - Nazira Begum
- Cryobiology Laboratory, National Centre for Polar and Ocean Research, Vasco da Gama, Goa, India
| | - Archana Singh
- Cryobiology Laboratory, National Centre for Polar and Ocean Research, Vasco da Gama, Goa, India
| | - Femi Anna Thomas
- Cryobiology Laboratory, National Centre for Polar and Ocean Research, Vasco da Gama, Goa, India
| | - Anu Gopinath
- Department of Aquatic Environment Management, Kerala University of Fisheries and Ocean Studies, Kochi, Kerala, India
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19
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Mahmoudi N, Enke TN, Beaupré SR, Teske AP, Cordero OX, Pearson A. Illuminating microbial species‐specific effects on organic matter remineralization in marine sediments. Environ Microbiol 2019; 22:1734-1747. [DOI: 10.1111/1462-2920.14871] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 10/15/2019] [Accepted: 11/19/2019] [Indexed: 11/28/2022]
Affiliation(s)
- Nagissa Mahmoudi
- Department of Earth and Planetary Sciences McGill University Montreal QC H3A 0E8
| | - Tim N. Enke
- Department of Civil and Environmental Engineering Massachusetts Institute of Technology (MIT) Cambridge Massachusetts 02139
| | - Steven R. Beaupré
- School of Marine and Atmospheric Sciences Stony Brook University Stony Brook New York 11794
| | - Andreas P. Teske
- Department of Marine Sciences University of North Carolina Chapel Hill North Carolina 27599
| | - Otto X. Cordero
- Department of Civil and Environmental Engineering Massachusetts Institute of Technology (MIT) Cambridge Massachusetts 02139
| | - Ann Pearson
- Department of Earth and Planetary Sciences Harvard University Cambridge Massachusetts 02138
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