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Costas-Selas C, Martínez-García S, Delgadillo-Nuño E, Justel-Díez M, Fuentes-Lema A, Fernández E, Teira E. Linking the impact of bacteria on phytoplankton growth with microbial community composition and co-occurrence patterns. MARINE ENVIRONMENTAL RESEARCH 2024; 193:106262. [PMID: 38035521 DOI: 10.1016/j.marenvres.2023.106262] [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: 07/14/2023] [Revised: 11/06/2023] [Accepted: 11/09/2023] [Indexed: 12/02/2023]
Abstract
The interactions between microalgae and bacteria have recently emerged as key control factors which might contribute to a better understanding on how phytoplankton communities assemble and respond to environmental disturbances. We analyzed partial 16S rRNA and 18S rRNA genes from a total of 42 antibiotic bioassays, where phytoplankton growth was assessed in the presence or absence of an active bacterial community. A significant negative impact of bacteria was observed in 18 bioassays, a significant positive impact was detected in 5 of the cases, and a non-detectable effect occurred in 19 bioassays. Thalasiossira spp., Chlorophytes, Vibrionaceae and Alteromonadales were relatively more abundant in the samples where a positive effect of bacteria was observed compared to those where a negative impact was observed. Phytoplankton diversity was lower when bacteria negatively affect their growth than when the effect was beneficial. The phytoplankton-bacteria co-occurrence subnetwork included many significant Chlorophyta-Alteromonadales and Bacillariophyceae-Alteromonadales positive associations. Phytoplankton-bacteria co-exclusions were not detected in the network, which contrasts with the negative effect of bacteria on phytoplankton growth frequently detected in the bioassays, suggesting strong competitive interactions. Overall, this study adds strong evidence supporting the key role of phytoplankton-bacteria interactions in the microbial communities.
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Affiliation(s)
- Cecilia Costas-Selas
- Centro de Investigación Mariña, Universidade de Vigo, Departamento de Ecoloxía e Bioloxía Animal, 36310, Vigo, Spain.
| | - Sandra Martínez-García
- Centro de Investigación Mariña, Universidade de Vigo, Departamento de Ecoloxía e Bioloxía Animal, 36310, Vigo, Spain.
| | - Erick Delgadillo-Nuño
- Centro de Investigación Mariña, Universidade de Vigo, Departamento de Ecoloxía e Bioloxía Animal, 36310, Vigo, Spain.
| | - Maider Justel-Díez
- Centro de Investigación Mariña, Universidade de Vigo, Departamento de Ecoloxía e Bioloxía Animal, 36310, Vigo, Spain.
| | - Antonio Fuentes-Lema
- Centro de Investigación Mariña, Universidade de Vigo, Departamento de Ecoloxía e Bioloxía Animal, 36310, Vigo, Spain.
| | - Emilio Fernández
- Centro de Investigación Mariña, Universidade de Vigo, Departamento de Ecoloxía e Bioloxía Animal, 36310, Vigo, Spain.
| | - Eva Teira
- Centro de Investigación Mariña, Universidade de Vigo, Departamento de Ecoloxía e Bioloxía Animal, 36310, Vigo, Spain.
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2
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Lai D, Hedlund BP, Mau RL, Jiao JY, Li J, Hayer M, Dijkstra P, Schwartz E, Li WJ, Dong H, Palmer M, Dodsworth JA, Zhou EM, Hungate BA. Resource partitioning and amino acid assimilation in a terrestrial geothermal spring. THE ISME JOURNAL 2023; 17:2112-2122. [PMID: 37741957 PMCID: PMC10579274 DOI: 10.1038/s41396-023-01517-7] [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: 05/24/2023] [Revised: 08/31/2023] [Accepted: 09/13/2023] [Indexed: 09/25/2023]
Abstract
High-temperature geothermal springs host simplified microbial communities; however, the activities of individual microorganisms and their roles in the carbon cycle in nature are not well understood. Here, quantitative stable isotope probing (qSIP) was used to track the assimilation of 13C-acetate and 13C-aspartate into DNA in 74 °C sediments in Gongxiaoshe Hot Spring, Tengchong, China. This revealed a community-wide preference for aspartate and a tight coupling between aspartate incorporation into DNA and the proliferation of aspartate utilizers during labeling. Both 13C incorporation into DNA and changes in the abundance of taxa during incubations indicated strong resource partitioning and a significant phylogenetic signal for aspartate incorporation. Of the active amplicon sequence variants (ASVs) identified by qSIP, most could be matched with genomes from Gongxiaoshe Hot Spring or nearby springs with an average nucleotide similarity of 99.4%. Genomes corresponding to aspartate primary utilizers were smaller, near-universally encoded polar amino acid ABC transporters, and had codon preferences indicative of faster growth rates. The most active ASVs assimilating both substrates were not abundant, suggesting an important role for the rare biosphere in the community response to organic carbon addition. The broad incorporation of aspartate into DNA over acetate by the hot spring community may reflect dynamic cycling of cell lysis products in situ or substrates delivered during monsoon rains and may reflect N limitation.
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Affiliation(s)
- Dengxun Lai
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV, USA
| | - Brian P Hedlund
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV, USA.
- Nevada Institute for Personalized Medicine, University of Nevada Las Vegas, Las Vegas, NV, USA.
| | - Rebecca L Mau
- Center for Ecosystem Science and Society, Northern Arizona University and Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, USA
| | - Jian-Yu Jiao
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Junhui Li
- Center for Ecosystem Science and Society, Northern Arizona University and Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, USA
| | - Michaela Hayer
- Center for Ecosystem Science and Society, Northern Arizona University and Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, USA
| | - Paul Dijkstra
- Center for Ecosystem Science and Society, Northern Arizona University and Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, USA
| | - Egbert Schwartz
- Center for Ecosystem Science and Society, Northern Arizona University and Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, USA
| | - Wen-Jun Li
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Hailiang Dong
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing, China and Department of Geology and Environmental Earth Science, Miami University, Oxford, OH, USA
| | - Marike Palmer
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV, USA
| | - Jeremy A Dodsworth
- Department of Biology, California State University, San Bernardino, CA, USA
| | - En-Min Zhou
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV, USA
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
- School of Resource Environment and Earth Science, Yunnan University, Kunming, China
| | - Bruce A Hungate
- Center for Ecosystem Science and Society, Northern Arizona University and Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, USA.
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3
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Deng T, He Z, Xu M, Dong M, Guo J, Sun G, Huang H. Species' functional traits and interactions drive nitrate-mediated sulfur-oxidizing community structure and functioning. mBio 2023; 14:e0156723. [PMID: 37702500 PMCID: PMC10653917 DOI: 10.1128/mbio.01567-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 07/18/2023] [Indexed: 09/14/2023] Open
Abstract
IMPORTANCE Understanding the processes and mechanisms governing microbial community assembly and their linkages to ecosystem functioning has long been a core issue in microbial ecology. An in-depth insight still requires combining with analyses of species' functional traits and microbial interactions. Our study showed how species' functional traits and interactions determined microbial community structure and functions by a well-controlled laboratory experiment with nitrate-mediated sulfur oxidation systems using high-throughput sequencing and culture-dependent technologies. The results provided solid evidences that species' functional traits and interactions were the intrinsic factors determining community structure and function. More importantly, our study established quantitative links between community structure and function based on species' functional traits and interactions, which would have important implications for the design and synthesis of microbiomes with expected functions.
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Affiliation(s)
- Tongchu Deng
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Institute of Microbiology, Guangdong Academy of Science, Guangzhou, China
- Guangdong Provincial Key Laboratory of Environmental Protection Microbiology and Regional Ecological Security, Guangzhou, Guangdong, China
| | - Zhili He
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Meiying Xu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Institute of Microbiology, Guangdong Academy of Science, Guangzhou, China
- Guangdong Provincial Key Laboratory of Environmental Protection Microbiology and Regional Ecological Security, Guangzhou, Guangdong, China
| | - Meijun Dong
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Institute of Microbiology, Guangdong Academy of Science, Guangzhou, China
- Guangdong Provincial Key Laboratory of Environmental Protection Microbiology and Regional Ecological Security, Guangzhou, Guangdong, China
| | - Jun Guo
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Institute of Microbiology, Guangdong Academy of Science, Guangzhou, China
- Guangdong Provincial Key Laboratory of Environmental Protection Microbiology and Regional Ecological Security, Guangzhou, Guangdong, China
| | - Guoping Sun
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Institute of Microbiology, Guangdong Academy of Science, Guangzhou, China
- Guangdong Provincial Key Laboratory of Environmental Protection Microbiology and Regional Ecological Security, Guangzhou, Guangdong, China
| | - Haobin Huang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Institute of Microbiology, Guangdong Academy of Science, Guangzhou, China
- Guangdong Provincial Key Laboratory of Environmental Protection Microbiology and Regional Ecological Security, Guangzhou, Guangdong, China
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4
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Mayali X, Samo TJ, Kimbrel JA, Morris MM, Rolison K, Swink C, Ramon C, Kim YM, Munoz-Munoz N, Nicora C, Purvine S, Lipton M, Stuart RK, Weber PK. Single-cell isotope tracing reveals functional guilds of bacteria associated with the diatom Phaeodactylum tricornutum. Nat Commun 2023; 14:5642. [PMID: 37704622 PMCID: PMC10499878 DOI: 10.1038/s41467-023-41179-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 08/24/2023] [Indexed: 09/15/2023] Open
Abstract
Bacterial remineralization of algal organic matter fuels algal growth but is rarely quantified. Consequently, we cannot currently predict whether some bacterial taxa may provide more remineralized nutrients to algae than others. Here, we quantified bacterial incorporation of algal-derived complex dissolved organic carbon and nitrogen and algal incorporation of remineralized carbon and nitrogen in fifteen bacterial co-cultures growing with the diatom Phaeodactylum tricornutum at the single-cell level using isotope tracing and nanoSIMS. We found unexpected strain-to-strain and cell-to-cell variability in net carbon and nitrogen incorporation, including non-ubiquitous complex organic nitrogen utilization and remineralization. We used these data to identify three distinct functional guilds of metabolic interactions, which we termed macromolecule remineralizers, macromolecule users, and small-molecule users, the latter exhibiting efficient growth under low carbon availability. The functional guilds were not linked to phylogeny and could not be elucidated strictly from metabolic capacity as predicted by comparative genomics, highlighting the need for direct activity-based measurements in ecological studies of microbial metabolic interactions.
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Affiliation(s)
- Xavier Mayali
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA.
| | - Ty J Samo
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Jeff A Kimbrel
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Megan M Morris
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Kristina Rolison
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Courtney Swink
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Christina Ramon
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Young-Mo Kim
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Nathalie Munoz-Munoz
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Carrie Nicora
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Sam Purvine
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Mary Lipton
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Rhona K Stuart
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
| | - Peter K Weber
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
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5
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Sun CC, Zhao WJ, Yue WZ, Cheng H, Sun FL, Wang YT, Wu ML, Engel A, Wang YS. Polymeric carbohydrates utilization separates microbiomes into niches: insights into the diversity of microbial carbohydrate-active enzymes in the inner shelf of the Pearl River Estuary, China. Front Microbiol 2023; 14:1180321. [PMID: 37425997 PMCID: PMC10322874 DOI: 10.3389/fmicb.2023.1180321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 05/31/2023] [Indexed: 07/11/2023] Open
Abstract
Polymeric carbohydrates are abundant and their recycling by microbes is a key process of the ocean carbon cycle. A deeper analysis of carbohydrate-active enzymes (CAZymes) can offer a window into the mechanisms of microbial communities to degrade carbohydrates in the ocean. In this study, metagenomic genes encoding microbial CAZymes and sugar transporter systems were predicted to assess the microbial glycan niches and functional potentials of glycan utilization in the inner shelf of the Pearl River Estuary (PRE). The CAZymes gene compositions were significantly different between in free-living (0.2-3 μm, FL) and particle-associated (>3 μm, PA) bacteria of the water column and between water and surface sediments, reflecting glycan niche separation on size fraction and selective degradation in depth. Proteobacteria and Bacteroidota had the highest abundance and glycan niche width of CAZymes genes, respectively. At the genus level, Alteromonas (Gammaproteobacteria) exhibited the greatest abundance and glycan niche width of CAZymes genes and were marked by a high abundance of periplasmic transporter protein TonB and members of the major facilitator superfamily (MFS). The increasing contribution of genes encoding CAZymes and transporters for Alteromonas in bottom water contrasted to surface water and their metabolism are tightly related with particulate carbohydrates (pectin, alginate, starch, lignin-cellulose, chitin, and peptidoglycan) rather than on the utilization of ambient-water DOC. Candidatus Pelagibacter (Alphaproteobacteria) had a narrow glycan niche and was primarily preferred for nitrogen-containing carbohydrates, while their abundant sugar ABC (ATP binding cassette) transporter supported the scavenging mode for carbohydrate assimilation. Planctomycetota, Verrucomicrobiota, and Bacteroidota had similar potential glycan niches in the consumption of the main component of transparent exopolymer particles (sulfated fucose and rhamnose containing polysaccharide and sulfated-N-glycan), developing considerable niche overlap among these taxa. The most abundant CAZymes and transporter genes as well as the widest glycan niche in the abundant bacterial taxa implied their potential key roles on the organic carbon utilization, and the high degree of glycan niches separation and polysaccharide composition importantly influenced bacterial communities in the coastal waters of PRE. These findings expand the current understanding of the organic carbon biotransformation, underlying the size-fractionated glycan niche separation near the estuarine system.
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Affiliation(s)
- Cui-Ci Sun
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- Daya Bay Marine Biology Research Station, Chinese Academy of Sciences, Shenzhen, China
| | - Wen-Jie Zhao
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Wei-Zhong Yue
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Hao Cheng
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Fu-Lin Sun
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- Daya Bay Marine Biology Research Station, Chinese Academy of Sciences, Shenzhen, China
| | - Yu-Tu Wang
- Daya Bay Marine Biology Research Station, Chinese Academy of Sciences, Shenzhen, China
| | - Mei-Lin Wu
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Anja Engel
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
| | - You-Shao Wang
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
- Daya Bay Marine Biology Research Station, Chinese Academy of Sciences, Shenzhen, China
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6
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Engineering an incubation environment that mimics in situ conditions for in vitro coastal microbiome studies. Biotechniques 2022; 73:183-191. [PMID: 36189957 PMCID: PMC9623733 DOI: 10.2144/btn-2022-0080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Coastal environments are dynamic and can vary widely on short- or long-term scales depending on location and weather. Incubation equipment that reflects these changes through programmable gradient light and temperature cycles would permit more precise in vitro coastal microbiome studies. Here we present an open-source incubation environment that mimics in situ conditions for in vitro coastal microbiome studies using a modified shaking water bath that has fully customizable temperature and light gradients that can also mimic real-time field conditions. We compared coastal microbial community profiles incubated in situ and in our build mimicking field conditions over 48 h. Analyses of congruence indicated significant overlap (p > 0.2) between microbial communities incubated in situ and in vitro at each time point.
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7
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Pontiller B, Martínez-García S, Joglar V, Amnebrink D, Pérez-Martínez C, González JM, Lundin D, Fernández E, Teira E, Pinhassi J. Rapid bacterioplankton transcription cascades regulate organic matter utilization during phytoplankton bloom progression in a coastal upwelling system. THE ISME JOURNAL 2022; 16:2360-2372. [PMID: 35804052 PMCID: PMC9478159 DOI: 10.1038/s41396-022-01273-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 06/01/2022] [Accepted: 06/16/2022] [Indexed: 11/09/2022]
Abstract
Coastal upwelling zones are hotspots of oceanic productivity, driven by phytoplankton photosynthesis. Bacteria, in turn, grow on and are the principal remineralizers of dissolved organic matter (DOM) produced in aquatic ecosystems. However, the molecular processes that key bacterial taxa employ to regulate the turnover of phytoplankton-derived DOM are not well understood. We therefore carried out comparative time-series metatranscriptome analyses of bacterioplankton in the Northwest Iberian upwelling system, using parallel sampling of seawater and mesocosms with in situ-like conditions. The mesocosm experiment uncovered a taxon-specific progression of transcriptional responses from bloom development (characterized by a diverse set of taxa in the orders Cellvibrionales, Rhodobacterales, and Pelagibacterales), over early decay (mainly taxa in the Alteromonadales and Flavobacteriales), to senescence phases (Flavobacteriales and Saprospirales taxa). Pronounced order-specific differences in the transcription of glycoside hydrolases, peptidases, and transporters were found, supporting that functional resource partitioning is dynamically structured by temporal changes in available DOM. In addition, comparative analysis of mesocosm and field samples revealed a high degree of metabolic plasticity in the degradation and uptake of carbohydrates and nitrogen-rich compounds, suggesting these gene systems critically contribute to modulating the stoichiometry of the labile DOM pool. Our findings suggest that cascades of transcriptional responses in gene systems for the utilization of organic matter and nutrients largely shape the fate of organic matter on the time scales typical of upwelling-driven phytoplankton blooms.
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8
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Patel N, Guillemette R, Lal R, Azam F. Bacterial surface interactions with organic colloidal particles: Nanoscale hotspots of organic matter in the ocean. PLoS One 2022; 17:e0272329. [PMID: 36006971 PMCID: PMC9409529 DOI: 10.1371/journal.pone.0272329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 07/19/2022] [Indexed: 11/19/2022] Open
Abstract
Colloidal particles constitute a substantial fraction of organic matter in the global ocean and an abundant component of the organic matter interacting with bacterial surfaces. Using E. coli ribosomes as model colloidal particles, we applied high-resolution atomic force microscopy to probe bacterial surface interactions with organic colloids to investigate particle attachment and relevant surface features. We observed the formation of ribosome films associating with marine bacteria isolates and natural seawater assemblages, and that bacteria readily utilized the added ribosomes as growth substrate. In exposure experiments ribosomes directly attached onto bacterial surfaces as 40–200 nm clusters and patches of individual particles. We found that certain bacterial cells expressed surface corrugations that range from 50–100 nm in size, and 20 nm deep. Furthermore, our AFM studies revealed surface pits in select bacteria that range between 50–300 nm in width, and 10–50 nm in depth. Our findings suggest novel adaptive strategies of pelagic marine bacteria for colloid capture and utilization as nutrients, as well as storage as nanoscale hotspots of DOM.
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Affiliation(s)
- Nirav Patel
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, United States of America
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
- * E-mail:
| | - Ryan Guillemette
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, United States of America
| | - Ratnesh Lal
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
| | - Farooq Azam
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, United States of America
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9
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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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10
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Toledo S, Peri PL, Correa OS, Montecchia MS, Gargaglione VB, Ladd B. Structure and function of soil microbial communities in fertile islands in austral drylands. AUSTRAL ECOL 2022. [DOI: 10.1111/aec.13151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Santiago Toledo
- Universidad Nacional de la Patagonia Austral (UNPA)‐CIT‐CONICET Postal address 9400 Río Gallegos Argentina
| | - Pablo Luis Peri
- Universidad Nacional de la Patagonia Austral (UNPA)‐CIT‐CONICET Postal address 9400 Río Gallegos Argentina
- Instituto Nacional de Tecnología Agropecuaria (INTA) Postal address 9400 Río Gallegos Argentina
| | - Olga Susana Correa
- Facultad de Agronomía, Departamento de Biología Aplicada y Alimentos Universidad de Buenos Aires (UBA) Postal address 1417 Buenos Aires Argentina
| | - Marcela Susana Montecchia
- Facultad de Agronomía, Departamento de Biología Aplicada y Alimentos Universidad de Buenos Aires (UBA) Postal address 1417 Buenos Aires Argentina
| | - Veronica Beatriz Gargaglione
- Universidad Nacional de la Patagonia Austral (UNPA)‐CIT‐CONICET Postal address 9400 Río Gallegos Argentina
- Instituto Nacional de Tecnología Agropecuaria (INTA) Postal address 9400 Río Gallegos Argentina
| | - Brenton Ladd
- Universidad científica del Sur, Lima, Peru ‐ Escuela de Agroforestería
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11
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Abstract
High-resolution imaging with secondary ion mass spectrometry (nanoSIMS) has become a standard method in systems biology and environmental biogeochemistry and is broadly used to decipher ecophysiological traits of environmental microorganisms, metabolic processes in plant and animal tissues, and cross-kingdom symbioses. When combined with stable isotope-labeling-an approach we refer to as nanoSIP-nanoSIMS imaging offers a distinctive means to quantify net assimilation rates and stoichiometry of individual cell-sized particles in both low- and high-complexity environments. While the majority of nanoSIP studies in environmental and microbial biology have focused on nitrogen and carbon metabolism (using 15N and 13C tracers), multiple advances have pushed the capabilities of this approach in the past decade. The development of a high-brightness oxygen ion source has enabled high-resolution metal analyses that are easier to perform, allowing quantification of metal distribution in cells and environmental particles. New preparation methods, tools for automated data extraction from large data sets, and analytical approaches that push the limits of sensitivity and spatial resolution have allowed for more robust characterization of populations ranging from marine archaea to fungi and viruses. NanoSIMS studies continue to be enhanced by correlation with orthogonal imaging and 'omics approaches; when linked to molecular visualization methods, such as in situ hybridization and antibody labeling, these techniques enable in situ function to be linked to microbial identity and gene expression. Here we present an updated description of the primary materials, methods, and calculations used for nanoSIP, with an emphasis on recent advances in nanoSIMS applications, key methodological steps, and potential pitfalls.
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Affiliation(s)
- Jennifer Pett-Ridge
- Lawrence Livermore National Lab, Physical and Life Science Directorate, Livermore, CA, USA.
| | - Peter K Weber
- Lawrence Livermore National Lab, Physical and Life Science Directorate, Livermore, CA, USA.
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12
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Dang C, Walkup JGV, Hungate BA, Franklin RB, Schwartz E, Morrissey EM. Phylogenetic organization in the assimilation of chemically distinct substrates by soil bacteria. Environ Microbiol 2021; 24:357-369. [PMID: 34811865 DOI: 10.1111/1462-2920.15843] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 11/05/2021] [Accepted: 11/05/2021] [Indexed: 11/30/2022]
Abstract
Soils are among the most biodiverse habitats on earth and while the species composition of microbial communities can influence decomposition rates and pathways, the functional significance of many microbial species and phylogenetic groups remains unknown. If bacteria exhibit phylogenetic organization in their function, this could enable ecologically meaningful classification of bacterial clades. Here, we show non-random phylogenetic organization in the rates of relative carbon assimilation for both rapidly mineralized substrates (amino acids and glucose) assimilated by many microbial taxa and slowly mineralized substrates (lipids and cellulose) assimilated by relatively few microbial taxa. When mapped onto bacterial phylogeny using ancestral character estimation this phylogenetic organization enabled the identification of clades involved in the decomposition of specific soil organic matter substrates. Phylogenetic organization in substrate assimilation could provide a basis for predicting the functional attributes of uncharacterized microbial taxa and understanding the significance of microbial community composition for soil organic matter decomposition.
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Affiliation(s)
- Chansotheary Dang
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV 26506, USA
| | - Jeth G V Walkup
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV 26506, USA
| | - Bruce A Hungate
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ 86011, USA.,Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Rima B Franklin
- Department of Biology, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Egbert Schwartz
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ 86011, USA.,Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Ember M Morrissey
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV 26506, USA
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13
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Kieft B, Li Z, Bryson S, Hettich RL, Pan C, Mayali X, Mueller RS. Phytoplankton exudates and lysates support distinct microbial consortia with specialized metabolic and ecophysiological traits. Proc Natl Acad Sci U S A 2021; 118:e2101178118. [PMID: 34620710 PMCID: PMC8521717 DOI: 10.1073/pnas.2101178118] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/09/2021] [Indexed: 11/18/2022] Open
Abstract
Blooms of marine phytoplankton fix complex pools of dissolved organic matter (DOM) that are thought to be partitioned among hundreds of heterotrophic microbes at the base of the food web. While the relationship between microbial consumers and phytoplankton DOM is a key component of marine carbon cycling, microbial loop metabolism is largely understood from model organisms and substrates. Here, we took an untargeted approach to measure and analyze partitioning of four distinct phytoplankton-derived DOM pools among heterotrophic populations in a natural microbial community using a combination of ecogenomics, stable isotope probing (SIP), and proteomics. Each 13C-labeled exudate or lysate from a diatom or a picocyanobacterium was preferentially assimilated by different heterotrophic taxa with specialized metabolic and physiological adaptations. Bacteroidetes populations, with their unique high-molecular-weight transporters, were superior competitors for DOM derived from diatom cell lysis, rapidly increasing growth rates and ribosomal protein expression to produce new relatively high C:N biomass. Proteobacteria responses varied, with relatively low levels of assimilation by Gammaproteobacteria populations, while copiotrophic Alphaproteobacteria such as the Roseobacter clade, with their diverse array of ABC- and TRAP-type transporters to scavenge monomers and nitrogen-rich metabolites, accounted for nearly all cyanobacteria exudate assimilation and produced new relatively low C:N biomass. Carbon assimilation rates calculated from SIP data show that exudate and lysate from two common marine phytoplankton are being used by taxonomically distinct sets of heterotrophic populations with unique metabolic adaptations, providing a deeper mechanistic understanding of consumer succession and carbon use during marine bloom events.
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Affiliation(s)
- Brandon Kieft
- Department of Microbiology, Oregon State University, Corvallis, OR 97331;
| | - Zhou Li
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830
- Graduate School of Genome Science and Technology, The University of Tennessee, Knoxville, TN 37996
| | - Samuel Bryson
- Department of Microbiology, Oregon State University, Corvallis, OR 97331
- Department of Civil & Environmental Engineering, The University of Washington, Seattle, WA 98195
| | - Robert L Hettich
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830
| | - Chongle Pan
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830
- Graduate School of Genome Science and Technology, The University of Tennessee, Knoxville, TN 37996
- Department of Microbiology and Plant Microbiology, University of Oklahoma, Norman, OK 73019
| | - Xavier Mayali
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550
| | - Ryan S Mueller
- Department of Microbiology, Oregon State University, Corvallis, OR 97331;
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14
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Campana S, Busch K, Hentschel U, Muyzer G, de Goeij JM. DNA-stable isotope probing (DNA-SIP) identifies marine sponge-associated bacteria actively utilizing dissolved organic matter (DOM). Environ Microbiol 2021; 23:4489-4504. [PMID: 34159693 PMCID: PMC8453545 DOI: 10.1111/1462-2920.15642] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 06/11/2021] [Accepted: 06/11/2021] [Indexed: 12/30/2022]
Abstract
Sponges possess exceptionally diverse associated microbial communities and play a major role in (re)cycling of dissolved organic matter (DOM) in marine ecosystems. Linking sponge-associated community structure with DOM utilization is essential to understand host-microbe interactions in the uptake, processing, and exchange of resources. We coupled, for the first time, DNA-stable isotope probing (DNA-SIP) with 16S rRNA amplicon sequencing in a sponge holobiont to identify which symbiotic bacterial taxa are metabolically active in DOM uptake. Parallel incubation experiments with the sponge Plakortis angulospiculatus were amended with equimolar quantities of unlabelled (12 C) and labelled (13 C) DOM. Seven bacterial amplicon sequence variants (ASVs), belonging to the phyla PAUC34f, Proteobacteria, Poribacteria, Nitrospirae, and Chloroflexi, were identified as the first active consumers of DOM. Our results support the predictions that PAUC34f, Poribacteria, and Chloroflexi are capable of organic matter degradation through heterotrophic carbon metabolism, while Nitrospirae may have a potential mixotrophic metabolism. We present a new analytical application of DNA-SIP to detect substrate incorporation into a marine holobiont with a complex associated bacterial community and provide new experimental evidence that links the identity of diverse sponge-associated bacteria to the consumption of DOM.
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Affiliation(s)
- Sara Campana
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240, 1090 GE Amsterdam, Netherlands
| | - Kathrin Busch
- Department of Marine Ecology, Research Unit Marine Symbioses, GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany
| | - Ute Hentschel
- Department of Marine Ecology, Research Unit Marine Symbioses, GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany
| | - Gerard Muyzer
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240, 1090 GE Amsterdam, Netherlands
| | - Jasper M de Goeij
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94240, 1090 GE Amsterdam, Netherlands.,CARMABI Foundation, Piscaderabaai z/n, P.O. Box 2090, Willemstad, Curaçao
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15
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Sörenson E, Capo E, Farnelid H, Lindehoff E, Legrand C. Temperature Stress Induces Shift From Co-Existence to Competition for Organic Carbon in Microalgae-Bacterial Photobioreactor Community - Enabling Continuous Production of Microalgal Biomass. Front Microbiol 2021; 12:607601. [PMID: 33643237 PMCID: PMC7905023 DOI: 10.3389/fmicb.2021.607601] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 01/12/2021] [Indexed: 12/17/2022] Open
Abstract
To better predict the consequences of environmental change on aquatic microbial ecosystems it is important to understand what enables community resilience. The mechanisms by which a microbial community maintain its overall function, for example, the cycling of carbon, when exposed to a stressor, can be explored by considering three concepts: biotic interactions, functional adaptations, and community structure. Interactions between species are traditionally considered as, e.g., mutualistic, parasitic, or neutral but are here broadly defined as either coexistence or competition, while functions relate to their metabolism (e.g., autotrophy or heterotrophy) and roles in ecosystem functioning (e.g., oxygen production, organic matter degradation). The term structure here align with species richness and diversity, where a more diverse community is though to exhibit a broader functional capacity than a less diverse community. These concepts have here been combined with ecological theories commonly used in resilience studies, i.e., adaptive cycles, panarchy, and cross-scale resilience, that describe how the status and behavior at one trophic level impact that of surrounding levels. This allows us to explore the resilience of a marine microbial community, cultivated in an outdoor photobioreactor, when exposed to a naturally occurring seasonal stress. The culture was monitored for 6weeks during which it was exposed to two different temperature regimes (21 ± 2 and 11 ± 1°C). Samples were taken for metatranscriptomic analysis, in order to assess the regulation of carbon uptake and utilization, and for amplicon (18S and 16S rRNA gene) sequencing, to characterize the community structure of both autotrophs (dominated by the green microalgae Mychonastes) and heterotrophs (associated bacterioplankton). Differential gene expression analyses suggested that community function at warm temperatures was based on concomitant utilization of inorganic and organic carbon assigned to autotrophs and heterotrophs, while at colder temperatures, the uptake of organic carbon was performed primarily by autotrophs. Upon the shift from high to low temperature, community interactions shifted from coexistence to competition for organic carbon. Network analysis indicated that the community structure showed opposite trends for autotrophs and heterotrophs in having either high or low diversity. Despite an abrupt change of temperature, the microbial community as a whole responded in a way that maintained the overall level of diversity and function within and across autotrophic and heterotrophic levels. This is in line with cross-scale resilience theory describing how ecosystems may balance functional overlaps within and functional redundancy between levels in order to be resilient to environmental change (such as temperature).
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Affiliation(s)
- Eva Sörenson
- Department of Biology and Environmental Science, Centre of Ecology and Evolution and Microbial Model Systems, Linnaeus University, Kalmar, Sweden
| | - Eric Capo
- Department of Chemistry, Umeå University, Umeå, Sweden
| | - Hanna Farnelid
- Department of Biology and Environmental Science, Centre of Ecology and Evolution and Microbial Model Systems, Linnaeus University, Kalmar, Sweden
| | - Elin Lindehoff
- Department of Biology and Environmental Science, Centre of Ecology and Evolution and Microbial Model Systems, Linnaeus University, Kalmar, Sweden
| | - Catherine Legrand
- Department of Biology and Environmental Science, Centre of Ecology and Evolution and Microbial Model Systems, Linnaeus University, Kalmar, Sweden
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16
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Liu S, Baetge N, Comstock J, Opalk K, Parsons R, Halewood E, English CJ, Giovannoni S, Bolaños LM, Nelson CE, Vergin K, Carlson CA. Stable Isotope Probing Identifies Bacterioplankton Lineages Capable of Utilizing Dissolved Organic Matter Across a Range of Bioavailability. Front Microbiol 2020; 11:580397. [PMID: 33117322 PMCID: PMC7575717 DOI: 10.3389/fmicb.2020.580397] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 09/03/2020] [Indexed: 01/04/2023] Open
Abstract
Bacterioplankton consume about half of the dissolved organic matter (DOM) produced by phytoplankton. DOM released from phytoplankton consists of a myriad of compounds that span a range of biological reactivity from labile to recalcitrant. Linking specific bacterioplankton lineages to the incorporation of DOM compounds into biomass is important to understand microbial niche partitioning. We conducted a series of DNA-stable isotope probing (SIP) experiments using 13C-labeled substrates of varying lability including amino acids, cyanobacteria lysate, and DOM from diatom and cyanobacteria isolates concentrated on solid phase extraction PPL columns (SPE-DOM). Amendments of substrates into Sargasso Sea bacterioplankton communities were conducted to explore microbial response and DNA-SIP was used to determine which lineages of Bacteria and Archaea were responsible for uptake and incorporation. Greater increases in bacterioplankton abundance and DOC removal were observed in incubations amended with cyanobacteria-derived lysate and amino acids compared to the SPE-DOM, suggesting that the latter retained proportionally more recalcitrant DOM compounds. DOM across a range of bioavailability was utilized by diverse prokaryotic taxa with copiotrophs becoming the most abundant 13C-incorporating taxa in the amino acid treatment and oligotrophs becoming the most abundant 13C-incorporating taxa in SPE-DOM treatments. The lineages that responded to SPE-DOM amendments were also prevalent in the mesopelagic of the Sargasso Sea, suggesting that PPL extraction of phytoplankton-derived DOM isolates compounds of ecological relevance to oligotrophic heterotrophic bacterioplankton. Our study indicates that DOM quality is an important factor controlling the diversity of the microbial community response, providing insights into the roles of different bacterioplankton in resource exploitation and efficiency of marine carbon cycling.
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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
| | - Nicholas Baetge
- Department of Ecology, Evolution, and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Jacqueline Comstock
- Department of Ecology, Evolution, and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Keri Opalk
- Department of Ecology, Evolution, and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Rachel Parsons
- Bermuda Institute of Ocean Sciences, Saint George, Bermuda
| | - Elisa Halewood
- Department of Ecology, Evolution, and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Chance J English
- Department of Ecology, Evolution, and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Stephen Giovannoni
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | - Luis M Bolaños
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | - Craig E Nelson
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, Department of Oceanography and Hawai'i Sea Grant, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, Honolulu, HI, United States
| | - Kevin Vergin
- Microbial DNA Analytics, Phoenix, OR, United States
| | - 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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17
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Pontiller B, Martínez-García S, Lundin D, Pinhassi J. Labile Dissolved Organic Matter Compound Characteristics Select for Divergence in Marine Bacterial Activity and Transcription. Front Microbiol 2020; 11:588778. [PMID: 33101262 PMCID: PMC7546218 DOI: 10.3389/fmicb.2020.588778] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 09/03/2020] [Indexed: 11/30/2022] Open
Abstract
Bacteria play a key role in the planetary carbon cycle partly because they rapidly assimilate labile dissolved organic matter (DOM) in the ocean. However, knowledge of the molecular mechanisms at work when bacterioplankton metabolize distinct components of the DOM pool is still limited. We, therefore, conducted seawater culture enrichment experiments with ecologically relevant DOM, combining both polymer and monomer model compounds for distinct compound classes. This included carbohydrates (polysaccharides vs. monosaccharides), proteins (polypeptides vs. amino acids), and nucleic acids (DNA vs. nucleotides). We noted pronounced changes in bacterial growth, activity, and transcription related to DOM characteristics. Transcriptional responses differed between compound classes, with distinct gene sets (“core genes”) distinguishing carbohydrates, proteins, and nucleic acids. Moreover, we found a strong divergence in functional transcription at the level of particular monomers and polymers (i.e., the condensation state), primarily in the carbohydrates and protein compound classes. These specific responses included a variety of cellular and metabolic processes that were mediated by distinct bacterial taxa, suggesting pronounced functional partitioning of organic matter. Collectively, our findings show that two important facets of DOM, compound class and condensation state, shape bacterial gene expression, and ultimately select for distinct bacterial (functional) groups. This emphasizes the interdependency of marine bacteria and labile carbon compounds for regulating the transformation of DOM in surface waters.
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Affiliation(s)
- Benjamin Pontiller
- Centre for Ecology and Evolution in Microbial Model Systems, Linnaeus University, Kalmar, Sweden
| | | | - Daniel Lundin
- Centre for Ecology and Evolution in Microbial Model Systems, Linnaeus University, Kalmar, Sweden
| | - Jarone Pinhassi
- Centre for Ecology and Evolution in Microbial Model Systems, Linnaeus University, Kalmar, Sweden
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18
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Lemonnier C, Perennou M, Eveillard D, Fernandez-Guerra A, Leynaert A, Marié L, Morrison HG, Memery L, Paillard C, Maignien L. Linking Spatial and Temporal Dynamic of Bacterioplankton Communities With Ecological Strategies Across a Coastal Frontal Area. FRONTIERS IN MARINE SCIENCE 2020. [DOI: 10.3389/fmars.2020.00376] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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19
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Kamalanathan M, Doyle SM, Xu C, Achberger AM, Wade TL, Schwehr K, Santschi PH, Sylvan JB, Quigg A. Exoenzymes as a Signature of Microbial Response to Marine Environmental Conditions. mSystems 2020; 5:e00290-20. [PMID: 32291350 PMCID: PMC7159900 DOI: 10.1128/msystems.00290-20] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 04/01/2020] [Indexed: 01/14/2023] Open
Abstract
Microbial heterotopic metabolism in the ocean is fueled by a supply of essential nutrients acquired via exoenzymes catalyzing depolymerization of high-molecular-weight compounds. Although the rates of activity for a variety of exoenzymes across various marine environments are well established, the factors regulating the production of these exoenzymes, and to some extent their correlation with microbial community composition, are less known. This study focuses on addressing these challenges using a mesocosm experiment that compared a natural seawater microbial community (control) and exposed (to oil) treatment. Exoenzyme activities for β-glucosidase, leucine aminopeptidase (LAP), and lipase were significantly correlated with dissolved nutrient concentrations. We measured correlations between carbon- and nitrogen-acquiring enzymes (β-glucosidase/lipase versus LAP) and found that the correlation of carbon-acquiring enzymes varies with the chemical nature of the available primary carbon source. Notably, a strong correlation between particulate organic carbon and β-glucosidase activity demonstrates their polysaccharide depolymerization in providing the carbon for microbial growth. Last, we show that exoenzyme activity patterns are not necessarily correlated with prokaryotic community composition, suggesting a redundancy of exoenzyme functions among the marine microbial community and substrate availability. This study provides foundational work for linking exoenzyme function with dissolved organic substrate and downstream processes in marine systems.IMPORTANCE Microbes release exoenzymes into the environment to break down complex organic matter and nutrients into simpler forms that can be assimilated and utilized, thereby addressing their cellular carbon, nitrogen, and phosphorus requirements. Despite its importance, the factors associated with the synthesis of exoenzymes are not clearly defined, especially for the marine environment. Here, we found that exoenzymes associated with nitrogen and phosphorus acquisition were strongly correlated with inorganic nutrient levels, while those associated with carbon acquisition depended on the type of organic carbon available. We also show a linear relationship between carbon- and nitrogen-acquiring exoenzymes and a strong correlation between microbial biomass and exoenzymes, highlighting their significance to microbial productivity. Last, we show that changes in microbial community composition are not strongly associated with changes in exoenzyme activity profiles, a finding which reveals a redundancy of exoenzyme activity functions among microbial community. These findings advance our understanding of previously unknown factors associated with exoenzyme production in the marine environment.
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Affiliation(s)
- Manoj Kamalanathan
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, Texas, USA
| | - Shawn M Doyle
- Department of Oceanography, Texas A&M University, College Station, Texas, USA
| | - Chen Xu
- Department of Marine Science, Texas A&M University at Galveston, Galveston, Texas, USA
| | - Amanda M Achberger
- Department of Oceanography, Texas A&M University, College Station, Texas, USA
| | - Terry L Wade
- Geochemical and Environmental Research Group, Texas A&M University, College Station, Texas, USA
| | - Kathy Schwehr
- Department of Marine Science, Texas A&M University at Galveston, Galveston, Texas, USA
| | - Peter H Santschi
- Department of Marine Science, Texas A&M University at Galveston, Galveston, Texas, USA
| | - Jason B Sylvan
- Department of Oceanography, Texas A&M University, College Station, Texas, USA
| | - Antonietta Quigg
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, Texas, USA
- Department of Oceanography, Texas A&M University, College Station, Texas, USA
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20
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Barnett SE, Buckley DH. Simulating metagenomic stable isotope probing datasets with MetaSIPSim. BMC Bioinformatics 2020; 21:37. [PMID: 32000676 PMCID: PMC6993524 DOI: 10.1186/s12859-020-3372-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 01/16/2020] [Indexed: 11/10/2022] Open
Abstract
Background DNA-stable isotope probing (DNA-SIP) links microorganisms to their in-situ function in diverse environmental samples. Combining DNA-SIP and metagenomics (metagenomic-SIP) allows us to link genomes from complex communities to their specific functions and improves the assembly and binning of these targeted genomes. However, empirical development of metagenomic-SIP methods is hindered by the complexity and cost of these studies. We developed a toolkit, ‘MetaSIPSim,’ to simulate sequencing read libraries for metagenomic-SIP experiments. MetaSIPSim is intended to generate datasets for method development and testing. To this end, we used MetaSIPSim generated data to demonstrate the advantages of metagenomic-SIP over a conventional shotgun metagenomic sequencing experiment. Results Through simulation we show that metagenomic-SIP improves the assembly and binning of isotopically labeled genomes relative to a conventional metagenomic approach. Improvements were dependent on experimental parameters and on sequencing depth. Community level G + C content impacted the assembly of labeled genomes and subsequent binning, where high community G + C generally reduced the benefits of metagenomic-SIP. Furthermore, when a high proportion of the community is isotopically labeled, the benefits of metagenomic-SIP decline. Finally, the choice of gradient fractions to sequence greatly influences method performance. Conclusions Metagenomic-SIP is a valuable method for recovering isotopically labeled genomes from complex communities. We show that metagenomic-SIP performance depends on optimization of experimental parameters. MetaSIPSim allows for simulation of metagenomic-SIP datasets which facilitates the optimization and development of metagenomic-SIP experiments and analytical approaches for dealing with these data.
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Affiliation(s)
- Samuel E Barnett
- School of Integrative Plant Science, Cornell University, Bradfield Hall, room 705, 306 Tower Rd, Ithaca, NY, 14853, USA
| | - Daniel H Buckley
- School of Integrative Plant Science, Cornell University, Bradfield Hall, room 705, 306 Tower Rd, Ithaca, NY, 14853, USA.
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21
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Mayali X. NanoSIMS: Microscale Quantification of Biogeochemical Activity with Large-Scale Impacts. ANNUAL REVIEW OF MARINE SCIENCE 2020; 12:449-467. [PMID: 31299167 DOI: 10.1146/annurev-marine-010419-010714] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
One major objective of aquatic microbial ecology is to understand the distribution of microbial populations over space and time and in response to environmental factors. Perhaps more importantly, it is crucial to quantify how those microbial cells affect biogeochemical processes of interest, such as primary production, nitrogen cycling, or the breakdown of pollutants. One valuable approach to link microbial identity to activity is to carry out incubations with stable-isotope-labeled substrates and then quantify the isotope incorporation by individual microbial cells using nanoscale secondary ion mass spectrometry (NanoSIMS). This review summarizes recent efforts in this field, highlights novel methods, describes studies investigating rare metabolisms as well as widespread microbial activity, and hopes to provide a framework to increase the use and capabilities of NanoSIMS for microbial biogeochemical studies in the future.
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Affiliation(s)
- Xavier Mayali
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA;
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22
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Li Z, Yao Q, Guo X, Crits-Christoph A, Mayes MA, Hervey WJ, Lebeis SL, Banfield JF, Hurst GB, Hettich RL, Pan C. Genome-Resolved Proteomic Stable Isotope Probing of Soil Microbial Communities Using 13CO 2 and 13C-Methanol. Front Microbiol 2019; 10:2706. [PMID: 31866955 PMCID: PMC6908837 DOI: 10.3389/fmicb.2019.02706] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 11/08/2019] [Indexed: 11/15/2022] Open
Abstract
Stable isotope probing (SIP) enables tracking the nutrient flows from isotopically labeled substrates to specific microorganisms in microbial communities. In proteomic SIP, labeled proteins synthesized by the microbial consumers of labeled substrates are identified with a shotgun proteomics approach. Here, proteomic SIP was combined with targeted metagenomic binning to reconstruct metagenome-assembled genomes (MAGs) of the microorganisms producing labeled proteins. This approach was used to track carbon flows from 13CO2 to the rhizosphere communities of Zea mays, Triticum aestivum, and Arabidopsis thaliana. Rhizosphere microorganisms that assimilated plant-derived 13C were capable of metabolic and signaling interactions with their plant hosts, as shown by their MAGs containing genes for phytohormone modulation, quorum sensing, and transport and metabolism of nutrients typical of those found in root exudates. XoxF-type methanol dehydrogenases were among the most abundant proteins identified in the rhizosphere metaproteomes. 13C-methanol proteomic SIP was used to test the hypothesis that XoxF was used to metabolize and assimilate methanol in the rhizosphere. We detected 7 13C-labeled XoxF proteins and identified methylotrophic pathways in the MAGs of 8 13C-labeled microorganisms, which supported the hypothesis. These two studies demonstrated the capability of proteomic SIP for functional characterization of active microorganisms in complex microbial communities.
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Affiliation(s)
- Zhou Li
- Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States.,Graduate School of Genome Science and Technology, The University of Tennessee, Knoxville, Knoxville, TN, United States.,Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Qiuming Yao
- Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Xuan Guo
- Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Alexander Crits-Christoph
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA, United States
| | - Melanie A Mayes
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - William Judson Hervey
- Naval Research Laboratory, Center for Biomolecular Science and Engineering, Washington, DC, United States
| | - Sarah L Lebeis
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Jillian F Banfield
- Department of Earth and Planetary Science, University of California, Berkeley, Berkeley, CA, United States.,Department of Environmental Science, Policy, and Management, University of California, Berkeley, Berkeley, CA, United States
| | - Gregory B Hurst
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Robert L Hettich
- Graduate School of Genome Science and Technology, The University of Tennessee, Knoxville, Knoxville, TN, United States.,Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Chongle Pan
- Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States.,Graduate School of Genome Science and Technology, The University of Tennessee, Knoxville, Knoxville, TN, United States.,School of Computer Science and Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, United States
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23
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Krüger K, Chafee M, Ben Francis T, Glavina Del Rio T, Becher D, Schweder T, Amann RI, Teeling H. In marine Bacteroidetes the bulk of glycan degradation during algae blooms is mediated by few clades using a restricted set of genes. ISME JOURNAL 2019; 13:2800-2816. [PMID: 31316134 PMCID: PMC6794258 DOI: 10.1038/s41396-019-0476-y] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 07/01/2019] [Accepted: 07/04/2019] [Indexed: 11/09/2022]
Abstract
We investigated Bacteroidetes during spring algae blooms in the southern North Sea in 2010–2012 using a time series of 38 deeply sequenced metagenomes. Initial partitioning yielded 6455 bins, from which we extracted 3101 metagenome-assembled genomes (MAGs) including 1286 Bacteroidetes MAGs covering ~120 mostly uncultivated species. We identified 13 dominant, recurrent Bacteroidetes clades carrying a restricted set of conserved polysaccharide utilization loci (PULs) that likely mediate the bulk of bacteroidetal algal polysaccharide degradation. The majority of PULs were predicted to target the diatom storage polysaccharide laminarin, alpha-glucans, alpha-mannose-rich substrates, and sulfated xylans. Metaproteomics at 14 selected points in time revealed expression of SusC-like proteins from PULs targeting all of these substrates. Analyses of abundant key players and their PUL repertoires over time furthermore suggested that fewer and simpler polysaccharides dominated early bloom stages, and that more complex polysaccharides became available as blooms progressed.
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Affiliation(s)
- Karen Krüger
- Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359, Bremen, Germany
| | - Meghan Chafee
- Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359, Bremen, Germany
| | - T Ben Francis
- Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359, Bremen, Germany
| | | | - Dörte Becher
- Institute for Microbiology, University Greifswald, Felix-Hausdorff-Straße 8, 17489, Greifswald, Germany
| | - Thomas Schweder
- Pharmaceutical Biotechnology, Institute of Pharmacy, University Greifswald, Felix-Hausdorff-Straße 3, 17487, Greifswald, Germany.,Institute of Marine Biotechnology, Walther-Rathenau-Straße 49a, 17489, Greifswald, Germany
| | - Rudolf I Amann
- Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359, Bremen, Germany.
| | - Hanno Teeling
- Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359, Bremen, Germany.
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24
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Nguyen TTH, Myrold DD, Mueller RS. Distributions of Extracellular Peptidases Across Prokaryotic Genomes Reflect Phylogeny and Habitat. Front Microbiol 2019; 10:413. [PMID: 30891022 PMCID: PMC6411800 DOI: 10.3389/fmicb.2019.00413] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 02/18/2019] [Indexed: 11/19/2022] Open
Abstract
Proteinaceous compounds are abundant forms of organic nitrogen in soil and aquatic ecosystems, and the rate of protein depolymerization, which is accomplished by a diverse range of microbial secreted peptidases, often limits nitrogen turnover in the environment. To determine if the distribution of secreted peptidases reflects the ecological and evolutionary histories of different taxa, we analyzed their distribution across prokaryotic lineages. Peptidase gene sequences of 147 archaeal and 2,191 bacterial genomes from the MEROPS database were screened for secretion signals, resulting in 55,072 secreted peptidases belonging to 148 peptidase families. These data, along with their corresponding 16S rRNA sequences, were used in our analysis. Overall, Bacteria had a much wider collection of secreted peptidases, higher average numbers of secreted peptidases per genome, and more unique peptidase families than Archaea. We found that the distribution of secreted peptidases corresponded to phylogenetic relationships among Bacteria and Archaea and often segregated according to microbial lifestyles, suggesting that the secreted peptidase complements of microbial taxa are optimized for the environmental microhabitats they occupy. Our analyses provide the groundwork for examining the specific functional role of families of secreted peptidases in relationship to the organisms and the corresponding environments in which they function.
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Affiliation(s)
- Trang T. H. Nguyen
- Department of Crop and Soil Science, Oregon State University, Corvallis, OR, United States
| | - David D. Myrold
- Department of Crop and Soil Science, Oregon State University, Corvallis, OR, United States
| | - Ryan S. Mueller
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
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25
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Abstract
Chip-SIP is a stable isotope probing (SIP) method for linking microbial identity and function in mixed communities and is capable of analyzing multiple isotopes (13C, 15N, and 18O) simultaneously. This method uses a high-density microarray to separate taxon-specific 16S (or 18S) rRNA genes and a high sensitivity magnetic sector secondary ion mass spectrometer (SIMS) to determine the relative isotope incorporation of the rRNA at each probe location. Using a maskless array synthesizer (MAS), we synthesize multiple unique sequences to target hundreds of taxa at the ribosomal operational taxonomic unit (OTU) level on an array surface, and then analyze it with a NanoSIMS 50, using its high-spatial resolution imaging capability to generate isotope ratios for individual probes. The Chip-SIP method has been used in diverse systems, including surface marine and estuarine water, rhizosphere, and peat soils, to quantify taxon-specific relative incorporation of different substrates in complex microbial communities. Depending on the hypothesis and experimental design, Chip-SIP allows the user to compare the same community incorporating different substrates, different communities incorporating the same substrate(s), or quantify how a community responds to treatment effects, such as temperature or nutrient concentrations.
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26
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Selfish, sharing and scavenging bacteria in the Atlantic Ocean: a biogeographical study of bacterial substrate utilisation. ISME JOURNAL 2018; 13:1119-1132. [PMID: 30531893 PMCID: PMC6474216 DOI: 10.1038/s41396-018-0326-3] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Revised: 11/06/2018] [Accepted: 11/23/2018] [Indexed: 12/12/2022]
Abstract
Identifying the roles played by individual heterotrophic bacteria in the degradation of high molecular weight (HMW) substrates is critical to understanding the constraints on carbon cycling in the ocean. At five sites in the Atlantic Ocean, we investigated the processing of organic matter by tracking changes in microbial community composition as HMW polysaccharides were enzymatically hydrolysed over time. During this investigation, we discovered that a considerable fraction of heterotrophic bacteria uses a newly-identified ‘selfish’ mode of substrate processing. We therefore additionally examined the balance of individual substrate utilisation mechanisms at different locations by linking individual microorganisms to distinct substrate utilisation mechanisms. Through FISH and uptake of fluorescently-labelled polysaccharides, ‘selfish’ organisms were identified as belonging to the Bacteroidetes, Planctomycetes and Gammaproteobacteria. ‘Sharing’ (extracellular enzyme producing) and ‘scavenging’ (non-enzyme producing) organisms predominantly belonged to the Alteromonadaceae and SAR11 clades, respectively. The extent to which individual mechanisms prevail depended on the initial population structure of the bacterial community at a given location and time, as well as the growth rate of specific bacteria. Furthermore, the same substrate was processed in different ways by different members of a pelagic microbial community, pointing to significant follow-on effects for carbon cycling.
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27
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Kieft B, Li Z, Bryson S, Crump BC, Hettich R, Pan C, Mayali X, Mueller RS. Microbial Community Structure-Function Relationships in Yaquina Bay Estuary Reveal Spatially Distinct Carbon and Nitrogen Cycling Capacities. Front Microbiol 2018; 9:1282. [PMID: 29963029 PMCID: PMC6010575 DOI: 10.3389/fmicb.2018.01282] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 05/25/2018] [Indexed: 12/11/2022] Open
Abstract
Linking microbial community structure to ecological processes requires understanding of the functional roles among individual populations and the factors that influence their distributions. These structure–function relationships are particularly difficult to disentangle in estuaries, due to highly variable physico-chemical conditions. Yet, examining microbe-mediated turnover of resources in these “bioreactor” ecosystems is critical for understanding estuarine ecology. In this study, a combined metagenomics and metaproteomics approach was used to show that the unequal distribution of microbial populations across the Yaquina Bay estuary led to a habitat-specific taxonomic and functional structure and a clear spatial distribution in microbe-mediated capacities for cycling of carbon and nitrogen. For example, size-fractionation revealed that communities inhabiting suspended particulate material encoded more diverse types of metabolisms (e.g., fermentation and denitrification) than those with a planktonic lifestyle, suggesting that the metabolic reactions can differ between size fractions of the same parcel of an estuarine water column. Similarly, communities inhabiting oligotrophic conditions in the lower estuary were enriched in genes involved in central carbon metabolism (e.g., TCA cycle), while communities in the upper estuary were enriched in genes typical of copiotrophic populations (e.g., cell growth, cell division). Integrating gene and protein data revealed that abundant populations of Flavobacteriales and Rhodobacterales encoded similar genomic functions, yet differed significantly in protein expression, dedicating a large proportion of their respective proteomes to rapid growth and division versus metabolic versatility and resource acquisition. This suggested potentially distinct life-strategies between these two co-occurring lineages and was concomitant with differing patterns of positive evolutionary selection on their encoded genes. Microbial communities and their functions across Yaquina Bay appear to be structured by population-level habitat preferences, resulting in spatially distinct elemental cycling, while within each community, forces such as competitive exclusion and evolutionary selection influence species life-strategies and may help maintain microbial diversity.
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Affiliation(s)
- Brandon Kieft
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | - Zhou Li
- Oak Ridge National Laboratory, Oak Ridge, TN, United States.,Graduate School of Genome Science and Technology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Samuel Bryson
- Department of Civil and Environmental Engineering, The University of Washington, Seattle, WA, United States
| | - Byron C Crump
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, United States
| | - Robert Hettich
- Oak Ridge National Laboratory, Oak Ridge, TN, United States.,Graduate School of Genome Science and Technology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Chongle Pan
- Oak Ridge National Laboratory, Oak Ridge, TN, United States.,Graduate School of Genome Science and Technology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Xavier Mayali
- Lawrence Livermore National Laboratory, U.S. Department of Energy, Livermore, CA, United States
| | - Ryan S Mueller
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
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