1
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Barbosa AB, Mosley BA, Galvão HM, Domingues RB. Short-Term Effects of Climate Change on Planktonic Heterotrophic Prokaryotes in a Temperate Coastal Lagoon: Temperature Is Good, Ultraviolet Radiation Is Bad, and CO 2 Is Neutral. Microorganisms 2023; 11:2559. [PMID: 37894217 PMCID: PMC10609585 DOI: 10.3390/microorganisms11102559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 10/05/2023] [Accepted: 10/12/2023] [Indexed: 10/29/2023] Open
Abstract
Planktonic heterotrophic prokaryotes (HProks) are a pivotal functional group in marine ecosystems and are highly sensitive to environmental variability and climate change. This study aimed to investigate the short-term effects of increasing carbon dioxide (CO2), ultraviolet radiation (UVR), and temperature on natural assemblages of HProks in the Ria Formosa coastal lagoon during winter. Two multi-stressor microcosm experiments were used to evaluate the isolated and combined effects of these environmental changes on HProk abundance, production, growth, and mortality rates. The isolated and combined effects of increased CO2 on HProks were not significant. However, HProk production, cellular activity, instantaneous growth rate, and mortality rate were negatively influenced by elevated UVR and positively influenced by warming. Stronger effects were detected on HProk mortality in relation to specific growth rate, leading to higher HProk net growth rates and abundance under elevated UVR and lower values under warming conditions.
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Affiliation(s)
| | | | | | - Rita B. Domingues
- CIMA—Centre for Marine and Environmental Research & ARNET—Infrastructure Network in Aquatic Research, Campus de Gambelas, University of Algarve, 8005-139 Faro, Portugal
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2
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Sánchez O, Ferrera I, Mabrito I, Gazulla CR, Sebastián M, Auladell A, Marín-Vindas C, Cardelús C, Sanz-Sáez I, Pernice MC, Marrasé C, Sala MM, Gasol JM. Seasonal impact of grazing, viral mortality, resource availability and light on the group-specific growth rates of coastal Mediterranean bacterioplankton. Sci Rep 2020; 10:19773. [PMID: 33188261 PMCID: PMC7666142 DOI: 10.1038/s41598-020-76590-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 10/19/2020] [Indexed: 11/25/2022] Open
Abstract
Estimation of prokaryotic growth rates is critical to understand the ecological role and contribution of different microbes to marine biogeochemical cycles. However, there is a general lack of knowledge on what factors control the growth rates of different prokaryotic groups and how these vary between sites and along seasons at a given site. We carried out several manipulation experiments during the four astronomical seasons in the coastal NW Mediterranean in order to evaluate the impact of grazing, viral mortality, resource competition and light on the growth and loss rates of prokaryotes. Gross and net growth rates of different bacterioplankton groups targeted by group-specific CARD-FISH probes and infrared microscopy (for aerobic anoxygenic phototrophs, AAP), were calculated from changes in cell abundances. Maximal group-specific growth rates were achieved when both predation pressure and nutrient limitation were experimentally minimized, while only a minimal effect of viral pressure on growth rates was observed; nevertheless, the response to predation removal was more remarkable in winter, when the bacterial community was not subjected to nutrient limitation. Although all groups showed increases in their growth rates when resource competition as well as grazers and viral pressure were reduced, Alteromonadaceae consistently presented the highest rates in all seasons. The response to light availability was generally weaker than that to the other factors, but it was variable between seasons. In summer and spring, the growth rates of AAP were stimulated by light whereas the growth of the SAR11 clade (likely containing proteorhodopsin) was enhanced by light in all seasons. Overall, our results set thresholds on bacterioplankton group-specific growth and mortality rates and contribute to estimate the seasonally changing contribution of various bacterioplankton groups to the function of microbial communities. Our results also indicate that the least abundant groups display the highest growth rates, contributing to the recycling of organic matter to a much greater extent than what their abundances alone would predict.
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Affiliation(s)
- Olga Sánchez
- Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, 08193, Bellaterra, Catalunya, Spain.
| | - Isabel Ferrera
- Centro Oceanográfico de Málaga, Instituto Español de Oceanografía, 29640, Fuengirola, Málaga, Spain. .,Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, ICM-CSIC, 08003, Barcelona, Catalunya, Spain.
| | - Isabel Mabrito
- Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, 08193, Bellaterra, Catalunya, Spain
| | - Carlota R Gazulla
- Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, 08193, Bellaterra, Catalunya, Spain.,Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, ICM-CSIC, 08003, Barcelona, Catalunya, Spain
| | - Marta Sebastián
- Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, ICM-CSIC, 08003, Barcelona, Catalunya, Spain.,Instituto de Oceanografía y Cambio Global (IOCAG), Universidad de Las Palmas de Gran Canaria (ULPGC), Telde, 35214, Spain
| | - Adrià Auladell
- Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, ICM-CSIC, 08003, Barcelona, Catalunya, Spain
| | - Carolina Marín-Vindas
- Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, ICM-CSIC, 08003, Barcelona, Catalunya, Spain.,Escuela de Ciencias Biológicas, Universidad Nacional, Heredia, 40101, Costa Rica
| | - Clara Cardelús
- Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, ICM-CSIC, 08003, Barcelona, Catalunya, Spain
| | - Isabel Sanz-Sáez
- Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, ICM-CSIC, 08003, Barcelona, Catalunya, Spain
| | - Massimo C Pernice
- Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, ICM-CSIC, 08003, Barcelona, Catalunya, Spain
| | - Cèlia Marrasé
- Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, ICM-CSIC, 08003, Barcelona, Catalunya, Spain
| | - M Montserrat Sala
- Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, ICM-CSIC, 08003, Barcelona, Catalunya, Spain
| | - Josep M Gasol
- Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, ICM-CSIC, 08003, Barcelona, Catalunya, Spain
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3
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Mena C, Reglero P, Balbín R, Martín M, Santiago R, Sintes E. Seasonal Niche Partitioning of Surface Temperate Open Ocean Prokaryotic Communities. Front Microbiol 2020; 11:1749. [PMID: 32849378 PMCID: PMC7399227 DOI: 10.3389/fmicb.2020.01749] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 07/03/2020] [Indexed: 12/20/2022] Open
Abstract
Surface microbial communities are exposed to seasonally changing environmental conditions, resulting in recurring patterns of community composition. However, knowledge on temporal dynamics of open ocean microbial communities remains scarce. Seasonal patterns and associations of taxa and oligotypes from surface and chlorophyll maximum layers in the western Mediterranean Sea were studied over a 2-year period. Summer stratification versus winter mixing governed not only the prokaryotic community composition and diversity but also the temporal dynamics and co-occurrence association networks of oligotypes. Flavobacteriales, Rhodobacterales, SAR11, SAR86, and Synechococcales oligotypes exhibited contrasting seasonal dynamics, and consequently, specific microbial assemblages and potential inter-oligotype connections characterized the different seasons. In addition, oligotypes composition and dynamics differed between surface and deep chlorophyll maximum (DCM) prokaryotic communities, indicating depth-related environmental gradients as a major factor affecting association networks between closely related taxa. Taken together, the seasonal and depth specialization of oligotypes suggest temporal dynamics of community composition and metabolism, influencing ecosystem function and global biogeochemical cycles. Moreover, our results indicate highly specific associations between microbes, pointing to keystone ecotypes and fine-tuning of the microbes realized niche.
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Affiliation(s)
- Catalina Mena
- Instituto Español de Oceanografía (IEO), Centre Oceanogràfic de les Balears, Ecosystem Oceanography Group (GRECO), Palma, Spain
| | - Patricia Reglero
- Instituto Español de Oceanografía (IEO), Centre Oceanogràfic de les Balears, Ecosystem Oceanography Group (GRECO), Palma, Spain
| | - Rosa Balbín
- Instituto Español de Oceanografía (IEO), Centre Oceanogràfic de les Balears, Ecosystem Oceanography Group (GRECO), Palma, Spain
| | - Melissa Martín
- Instituto Español de Oceanografía (IEO), Centre Oceanogràfic de les Balears, Ecosystem Oceanography Group (GRECO), Palma, Spain
| | - Rocío Santiago
- Instituto Español de Oceanografía (IEO), Centre Oceanogràfic de les Balears, Ecosystem Oceanography Group (GRECO), Palma, Spain
| | - Eva Sintes
- Instituto Español de Oceanografía (IEO), Centre Oceanogràfic de les Balears, Ecosystem Oceanography Group (GRECO), Palma, Spain
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4
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Arandia-Gorostidi N, González JM, Huete-Stauffer TM, Ansari MI, Morán XAG, Alonso-Sáez L. Light supports cell-integrity and growth rates of taxonomically diverse coastal photoheterotrophs. Environ Microbiol 2020; 22:3823-3837. [PMID: 32643243 DOI: 10.1111/1462-2920.15158] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 06/29/2020] [Accepted: 07/06/2020] [Indexed: 11/28/2022]
Abstract
Despite the widespread distribution of proteorhodopsin (PR)-containing bacteria in the oceans, the use of light-derived energy to promote bacterial growth has only been shown in a few bacterial isolates, and there is a paucity of data describing the metabolic effects of light on environmental photoheterotrophic taxa. Here, we assessed the effects of light on the taxonomic composition, cell integrity and growth responses of microbial communities in monthly incubations between spring and autumn under different environmental conditions. The photoheterotrophs expressing PR in situ were dominated by Pelagibacterales and SAR116 in July and November, while members of Euryarchaeota, Gammaproteobacteria and Bacteroidetes dominated the PR expression in spring. Cell-membrane integrity decreased under dark conditions throughout most of the assessment, with maximal effects in summer, under low-nutrient conditions. A positive effect of light on growth was observed in one incubation (out of nine), coinciding with a declining phytoplankton bloom. Light-enhanced growth was found in Gammaproteobacteria (Alteromonadales) and Bacteroidetes (Polaribacter and Tenacibaculum). Unexpectedly, some Pelagibacterales also exhibited higher growth rates under light conditions. We propose that the energy harvested by PRs helps to maintain cell viability in dominant coastal photoheterotrophic oligotrophs while promoting the growth of some widespread taxa benefiting from the decline of phytoplankton blooms.
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Affiliation(s)
- Nestor Arandia-Gorostidi
- Instituto Español de Oceanografía, Centro Oceanográfico de Gijón/Xixón, Gijón/Xixón, Asturias, Spain.,Department of Earth System Science, Stanford University, Stanford, CA, USA
| | - José M González
- Department of Microbiology, University of La Laguna, La Laguna, Spain
| | - Tamara M Huete-Stauffer
- Instituto Español de Oceanografía, Centro Oceanográfico de Gijón/Xixón, Gijón/Xixón, Asturias, Spain.,Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Mohd I Ansari
- Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Xosé Anxelu G Morán
- Red Sea Research Center, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Laura Alonso-Sáez
- Instituto Español de Oceanografía, Centro Oceanográfico de Gijón/Xixón, Gijón/Xixón, Asturias, Spain.,AZTI, Marine Research, Basque Research and Technology Alliance (BRTA), Txatxarramendi ugartea z/g, Sukarrieta, Bizkaia, 48395, Spain
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5
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Sala MM, Ruiz-González C, Borrull E, Azúa I, Baña Z, Ayo B, Álvarez-Salgado XA, Gasol JM, Duarte CM. Prokaryotic Capability to Use Organic Substrates Across the Global Tropical and Subtropical Ocean. Front Microbiol 2020; 11:918. [PMID: 32582044 PMCID: PMC7287293 DOI: 10.3389/fmicb.2020.00918] [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: 01/20/2020] [Accepted: 04/17/2020] [Indexed: 12/17/2022] Open
Abstract
Prokaryotes play a fundamental role in decomposing organic matter in the ocean, but little is known about how microbial metabolic capabilities vary at the global ocean scale and what are the drivers causing this variation. We aimed at obtaining the first global exploration of the functional capabilities of prokaryotes in the ocean, with emphasis on the under-sampled meso- and bathypelagic layers. We explored the potential utilization of 95 carbon sources with Biolog GN2 plates® in 441 prokaryotic communities sampled from surface to bathypelagic waters (down to 4,000 m) at 111 stations distributed across the tropical and subtropical Atlantic, Indian, and Pacific oceans. The resulting metabolic profiles were compared with biological and physico-chemical properties such as fluorescent dissolved organic matter (DOM) or temperature. The relative use of the individual substrates was remarkably consistent across oceanic regions and layers, and only the Equatorial Pacific Ocean showed a different metabolic structure. When grouping substrates by categories, we observed some vertical variations, such as an increased relative utilization of polymers in bathypelagic layers or a higher relative use of P-compounds or amino acids in the surface ocean. The increased relative use of polymers with depth, together with the increases in humic DOM, suggest that deep ocean communities have the capability to process complex DOM. Overall, the main identified driver of the metabolic structure of ocean prokaryotic communities was temperature. Our results represent the first global depiction of the potential use of a variety of carbon sources by prokaryotic communities across the tropical and the subtropical ocean and show that acetic acid clearly emerges as one of the most widely potentially used carbon sources in the ocean.
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Affiliation(s)
- Maria Montserrat Sala
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas, Barcelona, Spain
| | - Clara Ruiz-González
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas, Barcelona, Spain
| | - Encarna Borrull
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas, Barcelona, Spain
| | - Iñigo Azúa
- Department of Immunology, Microbiology, and Parasitology, Faculty of Science and Technology, University of the Basque Country UPV/EHU, Leioa, Spain
| | - Zuriñe Baña
- Department of Immunology, Microbiology, and Parasitology, Faculty of Science and Technology, University of the Basque Country UPV/EHU, Leioa, Spain
| | - Begoña Ayo
- Department of Immunology, Microbiology, and Parasitology, Faculty of Science and Technology, University of the Basque Country UPV/EHU, Leioa, Spain.,Research Centre for Experimental Marine Biology and Biotechnology PiE-UPV/EHU, Plentzia, Spain
| | | | - Josep M Gasol
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas, Barcelona, Spain.,Centre for Marine Ecosystems Research, School of Science, Edith Cowan University, Joondalup, WA, Australia
| | - Carlos M Duarte
- Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.,Department of Global Change Research, Instituto Mediterráneo de Estudios Avanzados-Universitat de les Illes Balears, Consejo Superior de Investigaciones Científicas, Esporles, Spain
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6
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Teira E, Logares R, Gutiérrez‐Barral A, Ferrera I, Varela MM, Morán XAG, Gasol JM. Impact of grazing, resource availability and light on prokaryotic growth and diversity in the oligotrophic surface global ocean. Environ Microbiol 2019; 21:1482-1496. [DOI: 10.1111/1462-2920.14581] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 02/26/2019] [Accepted: 03/02/2019] [Indexed: 12/14/2022]
Affiliation(s)
- Eva Teira
- Departamento de Ecoloxía e Bioloxía AnimalUniversidade de Vigo Vigo Spain
| | - Ramiro Logares
- Departamento de Biologia Marina i OceanografiaInstitut de Ciències del Mar, CSIC Barcelona Catalonia Spain
| | | | - Isabel Ferrera
- Departamento de Biologia Marina i OceanografiaInstitut de Ciències del Mar, CSIC Barcelona Catalonia Spain
- Instituto Español de OceanografíaCentro Oceanográfico de Málaga Fuengirola Spain
| | - Marta M. Varela
- Instituto Español de OceanografíaCentro Oceanográfico de A Coruña A Coruña Spain
| | - Xosé Anxelu G. Morán
- Red Sea Research Center, Division of Biological and Environmental Sciences and EngineeringKing Abdullah University of Science and Technology Thuwal Saudi Arabia
| | - Josep M. Gasol
- Departamento de Biologia Marina i OceanografiaInstitut de Ciències del Mar, CSIC Barcelona Catalonia Spain
- Centre for Marine Ecosystems ResearchEdith Cowan University Joondalup Western Australia Australia
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7
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Ortega-Retuerta E, Marrasé C, Muñoz-Fernández A, Sala MM, Simó R, Gasol JM. Seasonal dynamics of transparent exopolymer particles (TEP) and their drivers in the coastal NW Mediterranean Sea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 631-632:180-190. [PMID: 29525702 DOI: 10.1016/j.scitotenv.2018.02.341] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 02/28/2018] [Accepted: 02/28/2018] [Indexed: 05/26/2023]
Abstract
Transparent Exopolymer Particles (TEPs) are a subclass of organic particles with high impact in biogeochemical and ecological processes, such as the biological carbon pump, air-sea interactions, or the microbial loop. However, the complexity in production and consumption makes TEP dynamics hardly predictable, calling for the need of descriptive studies about the in situ dynamics of these particles. We followed monthly TEP dynamics and combined them with a dataset of environmental variables during three years in a coastal site of the oligotrophic North Western Mediterranean (Blanes Bay). TEP concentration, ranging from 11.3 to 289.1μgXGeqL-1 (average 81.7±11.7μgXGeqL-1), showed recurrent peaks in early summer (June-July). TEP were temporally disconnected from chlorophyll a maxima, that occurred in late winter and early spring (maxima 1.21μgL-1), but they were significantly related to the abundance of specific phytoplankton groups (diatoms and dinoflagellates) and also coincided with periods of low nutrient concentrations. The fraction of particulate organic carbon in the form of TEP (the TEP:POC and TEP:PM ratios) were also highest in early summer, indicating that TEP-enriched particles of low density accumulate in surface waters during stratified periods. We hypothesize that the accumulation of these particles affects the microbial food web by enhancing the activity of specific prokaryotic extracellular enzymes (esterase, β-glucosidase and alkaline phosphatase) and promoting the abundance of heterotrophic nanoflagellates.
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Affiliation(s)
- Eva Ortega-Retuerta
- Biologia Marina i Oceanografia, Institut de Ciències del Mar, CSIC, Barcelona, Catalunya, Spain; Sorbonne Université, CNRS, UMR 7621, Laboratoire d'Océanographie Microbienne, Observatoire Océanologique, Banyuls-sur-Mer, France.
| | - Cèlia Marrasé
- Biologia Marina i Oceanografia, Institut de Ciències del Mar, CSIC, Barcelona, Catalunya, Spain
| | - Ana Muñoz-Fernández
- Biologia Marina i Oceanografia, Institut de Ciències del Mar, CSIC, Barcelona, Catalunya, Spain
| | - M Montserrat Sala
- Biologia Marina i Oceanografia, Institut de Ciències del Mar, CSIC, Barcelona, Catalunya, Spain
| | - Rafel Simó
- Biologia Marina i Oceanografia, Institut de Ciències del Mar, CSIC, Barcelona, Catalunya, Spain
| | - Josep M Gasol
- Biologia Marina i Oceanografia, Institut de Ciències del Mar, CSIC, Barcelona, Catalunya, Spain
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8
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Molina V, Hernández K, Dorador C, Eissler Y, Hengst M, Pérez V, Harrod C. Bacterial Active Community Cycling in Response to Solar Radiation and Their Influence on Nutrient Changes in a High-Altitude Wetland. Front Microbiol 2016; 7:1823. [PMID: 27909430 PMCID: PMC5112256 DOI: 10.3389/fmicb.2016.01823] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 10/31/2016] [Indexed: 01/08/2023] Open
Abstract
Microbial communities inhabiting high-altitude spring ecosystems are subjected to extreme changes in solar irradiance and temperature throughout the diel cycle. Here, using 16S rRNA gene tag pyrosequencing (cDNA) we determined the composition of actively transcribing bacteria from spring waters experimentally exposed through the day (morning, noon, and afternoon) to variable levels of solar radiation and light quality, and evaluated their influence on nutrient recycling. Solar irradiance, temperature, and changes in nutrient dynamics were associated with changes in the active bacterial community structure, predominantly by Cyanobacteria, Verrucomicrobia, Proteobacteria, and 35 other Phyla, including the recently described Candidate Phyla Radiation (e.g., Parcubacteria, Gracilibacteria, OP3, TM6, SR1). Diversity increased at noon, when the highest irradiances were measured (3.3-3.9 H', 1125 W m-2) compared to morning and afternoon (0.6-2.8 H'). This shift was associated with a decrease in the contribution to pyrolibraries by Cyanobacteria and an increase of Proteobacteria and other initially low frequently and rare bacteria phyla (< 0.5%) in the pyrolibraries. A potential increase in the activity of Cyanobacteria and other phototrophic groups, e.g., Rhodobacterales, was observed and associated with UVR, suggesting the presence of photo-activated repair mechanisms to resist high levels of solar radiation. In addition, the percentage contribution of cyanobacterial sequences in the afternoon was similar to those recorded in the morning. The shifts in the contribution by Cyanobacteria also influenced the rate of change in nitrate, nitrite, and phosphate, highlighted by a high level of nitrate accumulation during hours of high radiation and temperature associated with nitrifying bacteria activity. We did not detect ammonia or nitrite oxidizing bacteria in situ, but both functional groups (Nitrosomona and Nitrospira) appeared mainly in pyrolibraries generated from dark incubations. In total, our results reveal that both the structure and the diversity of the active bacteria community was extremely dynamic through the day, and showed marked shifts in composition that influenced nutrient recycling, highlighting how abiotic variation affects potential ecosystem functioning.
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Affiliation(s)
- Verónica Molina
- Programa de Biodiversidad and Departamento de Biología, Facultad de Ciencias Naturales y Exactas, Observatorio de Ecología Microbiana, Universidad de Playa AnchaValparaíso, Chile
| | - Klaudia Hernández
- Centro de Investigación Marina Quintay, Facultad de Ecología y Recursos Naturales, Universidad Andres BelloValparaíso, Chile
| | - Cristina Dorador
- Laboratorio de Complejidad Microbiana y Ecología Funcional and Departamento de Biotecnología, Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de Antofagasta, AntofagastaChile
- Centre for Biotechnology and BioengineeringSantiago, Chile
| | - Yoanna Eissler
- Centro de Investigación y Gestión de Recursos Naturales, Instituto de Química y Bioquímica, Facultad de Ciencias, Universidad de ValparaísoValparaíso, Chile
| | - Martha Hengst
- Centre for Biotechnology and BioengineeringSantiago, Chile
- Departamento de Ciencias Farmacéuticas, Facultad de Ciencias, Universidad Católica del NorteAntofagasta, Chile
| | - Vilma Pérez
- Laboratorio de Complejidad Microbiana y Ecología Funcional and Departamento de Biotecnología, Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de Antofagasta, AntofagastaChile
- Centre for Biotechnology and BioengineeringSantiago, Chile
| | - Chris Harrod
- Fish and Stable Isotope Ecology Laboratory, Instituto de Ciencias Naturales Alexander von Humboldt, Facultad de Ciencias del Mar y Recursos Biológicos, Universidad de AntofagastaAntofagasta, Chile
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9
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Abstract
A microbe's growth rate helps to set its ecological success and its contribution to food web dynamics and biogeochemical processes. Growth rates at the community level are constrained by biomass and trophic interactions among bacteria, phytoplankton, and their grazers. Phytoplankton growth rates are approximately 1 d(-1), whereas most heterotrophic bacteria grow slowly, close to 0.1 d(-1); only a few taxa can grow ten times as fast. Data from 16S rRNA and other approaches are used to speculate about the growth rate and the life history strategy of SAR11, the most abundant clade of heterotrophic bacteria in the oceans. These strategies are also explored using genomic data. Although the methods and data are imperfect, the available data can be used to set limits on growth rates and thus on the timescale for changes in the composition and structure of microbial communities.
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Affiliation(s)
- David L Kirchman
- School of Marine Science and Policy, University of Delaware, Lewes, Delaware 19958;
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10
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Meziti A, Kormas KA, Moustaka-Gouni M, Karayanni H. Spatially uniform but temporally variable bacterioplankton in a semi-enclosed coastal area. Syst Appl Microbiol 2015; 38:358-67. [PMID: 25976032 DOI: 10.1016/j.syapm.2015.04.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 04/10/2015] [Accepted: 04/13/2015] [Indexed: 10/23/2022]
Abstract
Studies focusing on the temporal and spatial dynamics of bacterioplankton communities within littoral areas undergoing direct influences from the coast are quite limited. In addition, they are more complicated to resolve compared to communities in the open ocean. In order to elucidate the effects of spatial vs. temporal variability on bacterial communities in a highly land-influenced semi-enclosed gulf, surface bacterioplankton communities from five coastal sites in Igoumenitsa Gulf (Ionian Sea, Greece) were analyzed over a nine-month period using 16S rDNA 454-pyrosequencing. Temporal differences were more pronounced than spatial ones, with lower diversity indices observed during the summer months. During winter and early spring, bacterial communities were dominated by SAR11 representatives, while this pattern changed in May when they were abruptly replaced by members of Flavobacteriales, Pseudomonadales, and Alteromonadales. Additionally, correlation analysis showed high negative correlations between the presence of SAR11 OTUs in relation to temperature and sunlight that might have driven, directly or indirectly, the disappearance of these OTUs in the summer months. The dominance of SAR11 during the winter months further supported the global distribution of the clade, not only in the open-sea, but also in coastal systems. This study revealed that specific bacteria exhibited distinct succession patterns in an anthropogenic-impacted coastal system. The major bacterioplankton component was represented by commonly found marine bacteria exhibiting seasonal dynamics, while freshwater and terrestrial-related phylotypes were absent.
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Affiliation(s)
- Alexandra Meziti
- Department of Biological Applications and Technology, University of Ioannina, 45110 Ioannina, Greece
| | - Konstantinos A Kormas
- Department of Ichthyology and Aquatic Environment, University of Thessaly, 38446 Volos, Greece
| | - Maria Moustaka-Gouni
- Department of Botany, School of Biology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Hera Karayanni
- Department of Biological Applications and Technology, University of Ioannina, 45110 Ioannina, Greece.
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11
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Sempéré R, Para J, Tedetti M, Charrière B, Mallet M. Variability of Solar Radiation and CDOM in Surface Coastal Waters of the Northwestern Mediterranean Sea. Photochem Photobiol 2015; 91:851-61. [DOI: 10.1111/php.12434] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 02/04/2015] [Indexed: 11/29/2022]
Affiliation(s)
- Richard Sempéré
- Aix-Marseille Université, Mediterranean Institute of Oceanography (M I O); Université de Toulon; CNRS-INSU/IRD; Marseille France
| | - Julien Para
- Aix-Marseille Université, Mediterranean Institute of Oceanography (M I O); Université de Toulon; CNRS-INSU/IRD; Marseille France
| | - Marc Tedetti
- Aix-Marseille Université, Mediterranean Institute of Oceanography (M I O); Université de Toulon; CNRS-INSU/IRD; Marseille France
| | - Bruno Charrière
- Aix-Marseille Université, Mediterranean Institute of Oceanography (M I O); Université de Toulon; CNRS-INSU/IRD; Marseille France
- CEFREM; CNRS - Université de Perpignan; Marseille France
| | - Marc Mallet
- Université Paul Sabatier de Toulouse; Laboratoire d'Aérologie; Toulouse France
- CNRS Laboratoire d'Aérologie; Toulouse France
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12
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Diversity of marine microbes in a changing Mediterranean Sea. RENDICONTI LINCEI-SCIENZE FISICHE E NATURALI 2014. [DOI: 10.1007/s12210-014-0333-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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13
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Stegman MR, Cottrell MT, Kirchman DL. Leucine incorporation by aerobic anoxygenic phototrophic bacteria in the Delaware estuary. ISME JOURNAL 2014; 8:2339-48. [PMID: 24824666 DOI: 10.1038/ismej.2014.75] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 03/28/2014] [Accepted: 04/02/2014] [Indexed: 11/09/2022]
Abstract
Aerobic anoxygenic phototrophic (AAP) bacteria are well known to be abundant in estuaries, coastal regions and in the open ocean, but little is known about their activity in any aquatic ecosystem. To explore the activity of AAP bacteria in the Delaware estuary and coastal waters, single-cell (3)H-leucine incorporation by these bacteria was examined with a new approach that combines infrared epifluorescence microscopy and microautoradiography. The approach was used on samples from the Delaware coast from August through December and on transects through the Delaware estuary in August and November 2011. The percent of active AAP bacteria was up to twofold higher than the percentage of active cells in the rest of the bacterial community in the estuary. Likewise, the silver grain area around active AAP bacteria in microautoradiography preparations was larger than the area around cells in the rest of the bacterial community, indicating higher rates of leucine consumption by AAP bacteria. The cell size of AAP bacteria was 50% bigger than the size of other bacteria, about the same difference on average as measured for activity. The abundance of AAP bacteria was negatively correlated and their activity positively correlated with light availability in the water column, although light did not affect (3)H-leucine incorporation in light-dark experiments. Our results suggest that AAP bacteria are bigger and more active than other bacteria, and likely contribute more to organic carbon fluxes than indicated by their abundance.
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Affiliation(s)
- Monica R Stegman
- School of Marine Science and Policy, University of Delaware, Lewes, DE, USA
| | - Matthew T Cottrell
- School of Marine Science and Policy, University of Delaware, Lewes, DE, USA
| | - David L Kirchman
- School of Marine Science and Policy, University of Delaware, Lewes, DE, USA
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14
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Seasonal fluctuations in ionic concentrations drive microbial succession in a hypersaline lake community. ISME JOURNAL 2013; 8:979-90. [PMID: 24335829 DOI: 10.1038/ismej.2013.221] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 11/05/2013] [Accepted: 11/10/2013] [Indexed: 02/01/2023]
Abstract
Microbial community succession was examined over a two-year period using spatially and temporally coordinated water chemistry measurements, metagenomic sequencing, phylogenetic binning and de novo metagenomic assembly in the extreme hypersaline habitat of Lake Tyrrell, Victoria, Australia. Relative abundances of Haloquadratum-related sequences were positively correlated with co-varying concentrations of potassium, magnesium and sulfate, but not sodium, chloride or calcium ions, while relative abundances of Halorubrum, Haloarcula, Halonotius, Halobaculum and Salinibacter-related sequences correlated negatively with Haloquadratum and these same ionic factors. Nanohaloarchaea and Halorhabdus-related sequence abundances were inversely correlated with each other, but not other taxonomic groups. These data, along with predicted gene functions from nearly-complete assembled population metagenomes, suggest different ecological phenotypes for Nanohaloarchaea and Halorhabdus-related strains versus other community members. Nucleotide percent G+C compositions were consistently lower in community metagenomic reads from summer versus winter samples. The same seasonal G+C trends were observed within taxonomically binned read subsets from each of seven different genus-level archaeal groups. Relative seasonal abundances were also linked to percent G+C for assembled population genomes. Together, these data suggest that extreme ionic conditions may exert selective pressure on archaeal populations at the level of genomic nucleotide composition, thus contributing to seasonal successional processes. Despite the unavailability of cultured representatives for most of the organisms identified in this study, effective coordination of physical and biological measurements has enabled discovery and quantification of unexpected taxon-specific, environmentally mediated factors influencing microbial community structure.
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15
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Díez-Vives C, Gasol JM, Acinas SG. Spatial and temporal variability among marine Bacteroidetes populations in the NW Mediterranean Sea. Syst Appl Microbiol 2013; 37:68-78. [PMID: 24188570 DOI: 10.1016/j.syapm.2013.08.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 07/25/2013] [Accepted: 08/21/2013] [Indexed: 11/29/2022]
Abstract
The abundance and structure of Bacteroidetes populations at diverse temporal and spatial scales were investigated in the Northwestern Mediterranean Sea. At a temporal scale, their relative abundance exhibited a marked seasonality, since it was higher in spring and decreased in winter. Similarly, Bacteroidetes community structure encompassed three main groups (winter, spring and summer-fall), which mimicked global bacterioplankton seasonality. At the spatial scale, relative abundances were similar in all surface samples along an inshore-offshore transect, but they decreased with depth. Analysis of the community structure identified four markedly different groups mostly related to different depths. Interestingly, seasonal changes in abundance and community structure were not synchronized. Furthermore, richness was higher when Bacteroidetes were less abundant. The variability of Bacteroidetes contributions to community structure in the temporal and spatial scales was correlated with different environmental factors: day length was the most important factor at the temporal scale, and salinity at the spatial scale. The community composition in terms of phylotypes changed significantly over time and along the depth gradients, but season or depth-specific phylogenetic clusters were not identified. Delineation of coherent Bacteroidetes sub-clusters should help to uncover higher resolution patterns within Bacteroidetes, and explore associations with environmental and biological variables.
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Affiliation(s)
- Cristina Díez-Vives
- Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas (CSIC), ES-08003 Barcelona, Catalunya, Spain
| | - Josep M Gasol
- Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas (CSIC), ES-08003 Barcelona, Catalunya, Spain
| | - Silvia G Acinas
- Departament de Biologia Marina i Oceanografia, Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas (CSIC), ES-08003 Barcelona, Catalunya, Spain.
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16
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Bagi A, Pampanin DM, Brakstad OG, Kommedal R. Estimation of hydrocarbon biodegradation rates in marine environments: a critical review of the Q10 approach. MARINE ENVIRONMENTAL RESEARCH 2013; 89:83-90. [PMID: 23756048 DOI: 10.1016/j.marenvres.2013.05.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Revised: 05/08/2013] [Accepted: 05/11/2013] [Indexed: 06/02/2023]
Abstract
Offshore oil & gas industry is moving exploration and production activities into Arctic and deep water regions. Governmental regulations require environmental impact assessments before operations to evaluate the possible effects of accidental oil releases. These are often performed by numerical fate models, like the Oil Spill Contingency and Response (OSCAR) model, which has become an industry standard in Norway. In this model, biodegradation rates are adjusted to local conditions by temperature compensation according to a Q10 approach. Q10 is the multiplier by which rates of enzymatic reactions increase at a 10 °C temperature rise. Herein, this Q10 approach implemented in the OSCAR model is investigated based on published data and novel obtained results. Overall, biodegradation rate predictions calculated by temperature compensation are found to be questionable, and choosing one universal Q10 value is considered not feasible. The high variation in Q10 values is herein attributed to indirect effects of temperature.
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Affiliation(s)
- Andrea Bagi
- University of Stavanger, Faculty of Science and Technology, Department of Mathematics and Natural Science, Kristine Bonnevies vei 22, N-4036 Stavanger, Norway.
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17
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Coelho FJRC, Santos AL, Coimbra J, Almeida A, Cunha A, Cleary DFR, Calado R, Gomes NCM. Interactive effects of global climate change and pollution on marine microbes: the way ahead. Ecol Evol 2013; 3:1808-18. [PMID: 23789087 PMCID: PMC3686211 DOI: 10.1002/ece3.565] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 03/08/2013] [Accepted: 03/13/2013] [Indexed: 12/02/2022] Open
Abstract
Global climate change has the potential to seriously and adversely affect marine ecosystem functioning. Numerous experimental and modeling studies have demonstrated how predicted ocean acidification and increased ultraviolet radiation (UVR) can affect marine microbes. However, researchers have largely ignored interactions between ocean acidification, increased UVR and anthropogenic pollutants in marine environments. Such interactions can alter chemical speciation and the bioavailability of several organic and inorganic pollutants with potentially deleterious effects, such as modifying microbial-mediated detoxification processes. Microbes mediate major biogeochemical cycles, providing fundamental ecosystems services such as environmental detoxification and recovery. It is, therefore, important that we understand how predicted changes to oceanic pH, UVR, and temperature will affect microbial pollutant detoxification processes in marine ecosystems. The intrinsic characteristics of microbes, such as their short generation time, small size, and functional role in biogeochemical cycles combined with recent advances in molecular techniques (e.g., metagenomics and metatranscriptomics) make microbes excellent models to evaluate the consequences of various climate change scenarios on detoxification processes in marine ecosystems. In this review, we highlight the importance of microbial microcosm experiments, coupled with high-resolution molecular biology techniques, to provide a critical experimental framework to start understanding how climate change, anthropogenic pollution, and microbiological interactions may affect marine ecosystems in the future.
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Affiliation(s)
- Francisco J R C Coelho
- Department of Biology and CESAM, University of Aveiro, Campus de Santiago 3810-193, Aveiro, Portugal
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18
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Ruiz-González C, Simó R, Sommaruga R, Gasol JM. Away from darkness: a review on the effects of solar radiation on heterotrophic bacterioplankton activity. Front Microbiol 2013; 4:131. [PMID: 23734148 PMCID: PMC3661993 DOI: 10.3389/fmicb.2013.00131] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 05/06/2013] [Indexed: 12/22/2022] Open
Abstract
Heterotrophic bacterioplankton are main consumers of dissolved organic matter (OM) in aquatic ecosystems, including the sunlit upper layers of the ocean and freshwater bodies. Their well-known sensitivity to ultraviolet radiation (UVR), together with some recently discovered mechanisms bacteria have evolved to benefit from photosynthetically available radiation (PAR), suggest that natural sunlight plays a relevant, yet difficult to predict role in modulating bacterial biogeochemical functions in aquatic ecosystems. Three decades of experimental work assessing the effects of sunlight on natural bacterial heterotrophic activity reveal responses ranging from high stimulation to total inhibition. In this review, we compile the existing studies on the topic and discuss the potential causes underlying these contrasting results, with special emphasis on the largely overlooked influences of the community composition and the previous light exposure conditions, as well as the different temporal and spatial scales at which exposure to solar radiation fluctuates. These intricate sunlight-bacteria interactions have implications for our understanding of carbon fluxes in aquatic systems, yet further research is necessary before we can accurately evaluate or predict the consequences of increasing surface UVR levels associated with global change.
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Affiliation(s)
- Clara Ruiz-González
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar, CSICBarcelona, Spain
- Département des Sciences Biologiques, Université du Québéc à MontréalMontréal, QC, Canada
| | - Rafel Simó
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar, CSICBarcelona, Spain
| | - Ruben Sommaruga
- Laboratory of Aquatic Photobiology and Plankton Ecology, Institute of Ecology, University of InnsbruckInnsbruck, Austria
| | - Josep M. Gasol
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar, CSICBarcelona, Spain
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Santos AL, Gomes NCM, Henriques I, Almeida A, Correia A, Cunha A. Growth conditions influence UVB sensitivity and oxidative damage in an estuarine bacterial isolate. Photochem Photobiol Sci 2013; 12:974-86. [PMID: 23493991 DOI: 10.1039/c3pp25353h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dose-dependent variation of oxidative cellular damage imposed by UVB exposure in a representative estuarine bacterial strain, Pseudomonas sp. NT5I1.2B, was studied at different growth phases (mid-exponential, late-exponential, and stationary), growth temperatures (15 °C and 25 °C) and growth media (nutrient-rich Tryptic Soy Broth [TSB] and nutrient-poor M9). Survival and markers of oxidative damage (lipid peroxidation, protein carbonylation, DNA strand breakage, and DNA-protein cross-links) were monitored during exposure to increasing UVB doses (0-60 kJ m(-2)). Oxidative damage did not follow a clear linear dose-dependent pattern, particularly at high UVB doses (>10 kJ m(-2)), suggesting a dynamic interaction between damage induction and repair during irradiation and/or saturation of oxidative damage. Survival of stationary phase cells generally exceeded that of exponential phase cells by up to 33.5 times; the latter displayed enhanced levels of DNA-protein cross-links (up to 15.6-fold) and protein carbonylation (up to 6.0-fold). Survival of mid-exponential phase cells was generally higher at 15 °C than at 25 °C (up to 6.6-fold), which was accompanied by lower levels of DNA strand breaks (up to 4000-fold), suggesting a temperature effect on reactive oxygen species (ROS) generation and/or ROS interaction with cellular targets. Survival under medium-high UVB doses (>10 kJ m(-2)) was generally higher (up to 5.4-fold) in cells grown in TSB than in M9. These results highlight the influence of growth conditions preceding irradiation on the extent of oxidative damage induced by UVB exposure in bacteria.
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Affiliation(s)
- Ana L Santos
- Department of Biology & CESAM, University of Aveiro, Aveiro, Portugal
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20
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Matallana-Surget S, Villette C, Intertaglia L, Joux F, Bourrain M, Lebaron P. Response to UVB radiation and oxidative stress of marine bacteria isolated from South Pacific Ocean and Mediterranean Sea. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2012; 117:254-61. [DOI: 10.1016/j.jphotobiol.2012.09.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 09/17/2012] [Accepted: 09/25/2012] [Indexed: 10/27/2022]
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21
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Ngugi DK, Stingl U. Combined analyses of the ITS loci and the corresponding 16S rRNA genes reveal high micro- and macrodiversity of SAR11 populations in the Red Sea. PLoS One 2012; 7:e50274. [PMID: 23185592 PMCID: PMC3502338 DOI: 10.1371/journal.pone.0050274] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Accepted: 10/22/2012] [Indexed: 11/29/2022] Open
Abstract
Bacteria belonging to the SAR11 clade are among the most abundant prokaryotes in the pelagic zone of the ocean. 16S rRNA gene-based analyses indicate that they constitute up to 60% of the bacterioplankton community in the surface waters of the Red Sea. This extremely oligotrophic water body is further characterized by an epipelagic zone, which has a temperature above 24 °C throughout the year, and a remarkable uniform temperature (~22 °C) and salinity (~41 psu) from the mixed layer (~200 m) to the bottom at over 2000 m depth. Despite these conditions that set it apart from other marine environments, the microbiology of this ecosystem is still vastly understudied. Prompted by the limited phylogenetic resolution of the 16S rRNA gene, we extended our previous study by sequencing the internal transcribed spacer (ITS) region of SAR11 in different depths of the Red Sea's water column together with the respective 16S fragment. The overall diversity captured by the ITS loci was ten times higher than that of the corresponding 16S rRNA genes. Moreover, species estimates based on the ITS showed a highly diverse population of SAR11 in the mixed layer that became diminished in deep isothermal waters, which was in contrast to results of the related 16S rRNA genes. While the 16S rRNA gene-based sequences clustered into three phylogenetic subgroups, the related ITS fragments fell into several phylotypes that showed clear depth-dependent shifts in relative abundances. Blast-based analyses not only documented the observed vertical partitioning and universal co-occurrence of specific phylotypes in five other distinct oceanic provinces, but also highlighted the influence of ecosystem-specific traits (e.g., temperature, nutrient availability, and concentration of dissolved oxygen) on the population dynamics of this ubiquitous marine bacterium.
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MESH Headings
- Alphaproteobacteria/classification
- Alphaproteobacteria/genetics
- Base Sequence
- Biodiversity
- DNA, Bacterial
- DNA, Intergenic/classification
- DNA, Intergenic/genetics
- DNA, Intergenic/isolation & purification
- Ecosystem
- Genetic Loci
- Indian Ocean
- Molecular Sequence Data
- Phylogeny
- Plankton/classification
- Plankton/genetics
- RNA, Ribosomal, 16S/classification
- RNA, Ribosomal, 16S/genetics
- RNA, Ribosomal, 16S/isolation & purification
- Salinity
- Temperature
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Affiliation(s)
- David Kamanda Ngugi
- Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.
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