DOCSLIB.ORG

Uva-DARE (Digital Academic Repository)

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Uva-DARE (Digital Academic Repository) UvA-DARE (Digital Academic Repository) Ecophysiological aspects of algal host–virus interactions in a changing ocean Maat, D.S. Publication date 2016 Document Version Final published version Link to publication Citation for published version (APA): Maat, D. S. (2016). Ecophysiological aspects of algal host–virus interactions in a changing ocean. General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. UvA-DARE is a service provided by the library of the University of Amsterdam (https://dare.uva.nl) Download date:11 Oct 2021 Douwe Sybren Maat Ecophysiological aspects of algal host - virus interactions in a changing ocean Ecophysiological aspects of algal host - virus interactions in a changing ocean Douwe Sybren Maat Ecophysiological aspects of algal host - virus interactions in a changing ocean Douwe Sybren Maat Maat, D.S. Ecophysiological aspects of algal host – virus interactions in a changing ocean PhD thesis, University of Amsterdam Het werk voor dit proefschrift is uitgevoerd op het Koninklijk Nederlands Instituut voor On- derzoek der Zee (NIOZ), een instituut van de Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO). ISBN: 9789491407383 Graphic design cover and inside: Rachel van Esschoten, DivingDuck Design (www.divingduckdesing.nl) Printed by: Printed by: Gildeprint Drukkerijen, Enschede (www.gildeprint.nl) Ecophysiological aspects of algal host - virus interactions in a changing ocean ACADEMISCH PROEFSCHRIFT ter verkrijging van de graad van doctor aan de Universiteit van Amsterdam op gezag van de Rector Magnificus prof. dr. ir. K.I.J. Maex ten overstaan van een door het college voor promoties ingestelde commissie, in het openbaar te verdedigen in de Agnietenkapel op vrijdag 16 december 2016, te 16:00 uur door Douwe Sybren Maat geboren te Zwolle PROMOTIECOMMISSIE Promotor prof. dr. C.P.D. Brussaard NIOZ & Universiteit van Amsterdam Overige leden prof. dr. W.H. Wilson SAHFOS, UK prof. dr. J. Huisman Universiteit van Amsterdam prof. dr. L.J. Stal NIOZ & Universiteit van Amsterdam prof. dr. G. Muijzer Universiteit van Amsterdam prof. dr. K.R. Timmermans NIOZ & Rijksuniversiteit Groningen prof. dr. S. Schouten NIOZ & Universiteit Utrecht Faculteit der Natuurwetenschappen, Wiskunde en Informatica “You are not a drop in the ocean. You are the entire ocean in a drop” -Rumi- Contents Chapter 1 General Introduction _____________________________________________________ 9 Chapter 2 Elevated carbon dioxide and phosphorus limitation favor Micromonas pusilla through stimulated growth and reduced viral impact ______________29 Chapter 3 Increasing phosphorus limitation and viral infection impact lipid remodeling of picophytoplankter Micromonas pusilla ______________________55 Chapter 4 Acquisition of intact polar lipids from the prymnesiophyte Phaeocystis globosa by its lytic virus PgV-07T ________________________________________79 Chapter 5 Fatty acid dynamics during viral infection of Phaeocystis globosa _______ 103 Chapter 6 Combined phosphorus limitation and light stress prevent successful viral proliferation in the phytoplankton species Phaeocystis globosa, but not in Micromonas pusilla _________________________________ 129 Chapter 7 Both phosphorus and nitrogen limitation constrain viral proliferation in marine phytoplankton ______________________________________________ 151 Chapter 8 Virus production in phosphorus limited Micromonas pusilla stimulated by a supply of naturally low concentrations of different phosphorus sources, far into the lytic cycle ____________________________ 177 Chapter 9 Thesis Synthesis ______________________________________________________ 207 Addendum Summary _____________________________________________________________ 218 Samenvatting _________________________________________________________ 222 Author Contributions _________________________________________________ 227 Dankwoord ___________________________________________________________ 229 Chapter 1 General Introduction Chapter 1 Phytoplankton and the abiotic environment 1 Phytoplankton are unicellular photosynthetic organisms that are suspen- ded throughout the water column and form the base of most marine pelagic food webs. In the marine environment they are accountable for approximately 48.5 Pg of inorganic carbon uptake (primary production) per year, which is roughly half of annual primary production worldwide and 98% of total pri- mary production in the marine environment (Field et al. 1998). Phytoplankton primary production varies with space and time as the result of environmental conditions. The availability of dissolved inorganic carbon (DIC) in the water column, being the substrate for primary production, affects phytoplankton production. Especially during phytoplankton blooms is DIC rapidly depleted due to rapid growth (Codispoti et al. 1982, Riebesell et al. 1993). Light in the form of photosynthetically active radiation (PAR) is the source of energy for photosynthesis and as such it is another main factor that controls phyto- plankton primary production. When the intensity of the light is too low, for example at greater depth in the water column or in waters with high turbidity (e.g. sediment load or during a dense phytoplankton bloom) phytoplankton production is severely reduced (Cloern 1999). The same holds for a reduction in the duration of the light period by mixing or seasonal changes in the win- ter season in temperate and polar regions. Alternatively, reduced availability of obligatory mineral resources for phytoplankton such as nitrogen (N) and phosphorus (P) can limit phytoplankton growth (Reynolds 2006a). Shortage of nutrients can occur during phytoplankton spring blooms in eutrophic coastal waters, whereby strong increases in phytoplankton biomass quickly deplete a specific nutrient, leading to an abrupt inhibition of growth of the dominant species (Reid et al. 1990, Cloern 1996). Under oligotrophic conditions with low nutrient concentrations (e.g. coastal summer or open ocean), phytoplankton growth depends largely on nutrients that are supplied by recycling (Harris 1986, Howarth 1988, Moore et al. 2013). As different phytoplankton species have different resource requirements, the spatial and temporal variabilities in the environment also largely determine phytoplankton size distribution and taxonomic community composition (Tilman et al. 1982, Litchman and Klaus- meier 2008, Beardall et al. 2009). The composition of phytoplankton, in turn, largely determines the structure of the pelagic food web, and herewith the ef- ficiency of carbon sequestration (Reynolds 2006b). Global change, the increase in atmospheric and oceanic CO2 and warm- ing of the earth’s atmosphere and oceans (Stocker et al. 2013), directly affects abiotic variables relevant for phytoplankton growth (Beardall et al. 2009). The atmospheric CO2 concentration increased from 300 to over 400 µatm in the last 50 years and is still rising at unceasing rate (Stocker et al. 2013). Dissolu- tion of CO2 in marine waters increases the DIC availability for phytoplankton 10 General Introduction and lowers the pH (a process called ‘ocean acidification’; Riebesell & Tortell 2011). Laboratory studies showed that not all phytoplankton species are af- 1 fected by altered CO2 concentrations. Other phytoplankton species may show changed elemental stoichiometry and increased or reduced growth rates and primary production (Riebesell & Tortell 2011; Riebesell 2004). Mesocosm ex- periments have shown net increases for smaller-sized phytoplankton groups under elevated pCO2 (Engel et al. 2008, Brussaard et al. 2013). Moreover, anthropogenic CO2 emissions are almost certainly the main cause for global warming (Stocker et al. 2013). Molecules of CO2 absorb and reemit radiation in the atmosphere, thereby trapping energy and increasing the temperature (greenhouse effect). Warming of the ocean surface will lead to an extension of temporarily and permanently vertically stratified waters (Sarmiento et al. 1998, Sarmiento et al. 2004). Phytoplankton in the mixed layer may sub- sequently experience increased nutrient limitation, because nutrient supply from deeper waters will become strongly reduced and may even be halted (Behrenfeld et al. 2006). P-limitation is particularly thought to prevail in the future oceans, because bioavailable mineral N can also be produced by N2-fix- ation (Karl et al. 1997). Furthermore, light levels in the stratified layer will be more static, yielding an environment with relatively high light levels in the rel- atively shallow mixed layer and with statically low light deeper in the euphotic zone (Finkel et al. 2010, Winder and Sommer 2012). Global change might thus affect phytoplankton community composition, growth and production in the world’s seas and oceans, with possible consequences for food web structure
Load more

Recommended publications
  • Genome of Phaeocystis Globosa Virus Pgv-16T Highlights the Common Ancestry of the Largest Known DNA Viruses Infecting Eukaryotes
    Genome of Phaeocystis globosa virus PgV-16T highlights the common ancestry of the largest known DNA viruses infecting eukaryotes Sebastien Santinia, Sandra Jeudya, Julia Bartolia, Olivier Poirota, Magali Lescota, Chantal Abergela, Valérie Barbeb, K. Eric Wommackc, Anna A. M. Noordeloosd, Corina P. D. Brussaardd,e,1, and Jean-Michel Claveriea,f,1 aStructural and Genomic Information Laboratory, Unité Mixte de Recherche 7256, Centre National de la Recherche Scientifique, Aix-Marseille Université, 13288 Marseille Cedex 9, France; bCommissariat à l’Energie Atomique–Institut de Génomique, 91057 Evry Cedex, France; cDepartment of Plant and Soil Sciences, University of Delaware, Newark, DE 19711; dDepartment of Biological Oceanography, Royal Netherlands Institute for Sea Research, NL-1790 AB Den Burg (Texel), The Netherlands; eAquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands; and fService de Santé Publique et d’Information Médicale, Hôpital de la Timone, Assistance Publique–Hôpitaux de Marseille, FR-13385 Marseille, France Edited by James L. Van Etten, University of Nebraska, Lincoln, NE, and approved May 1, 2013 (received for review February 22, 2013) Large dsDNA viruses are involved in the population control of many viruses: 730 kb and 1.28 Mb for CroV and Megavirus chilensis, globally distributed species of eukaryotic phytoplankton and have respectively. Other studies, targeting virus-specific genes [e.g., a prominent role in bloom termination. The genus Phaeocystis (Hap- DNA polymerase B (8) or capsid proteins (9)] have suggested tophyta, Prymnesiophyceae) includes several high-biomass-forming a close phylogenetic relationship between Mimivirus and several phytoplankton species, such as Phaeocystis globosa, the blooms of giant dsDNA viruses infecting various unicellular algae such as which occur mostly in the coastal zone of the North Atlantic and the Pyramimonas orientalis (Chlorophyta, Prasinophyceae), Phaeocys- North Sea.
    [Show full text]
  • Resilience of Microbial Communities After Hydrogen Peroxide Treatment of a Eutrophic Lake to Suppress Harmful Cyanobacterial Blooms
    microorganisms Article Resilience of Microbial Communities after Hydrogen Peroxide Treatment of a Eutrophic Lake to Suppress Harmful Cyanobacterial Blooms Tim Piel 1,†, Giovanni Sandrini 1,†,‡, Gerard Muyzer 1 , Corina P. D. Brussaard 1,2 , Pieter C. Slot 1, Maria J. van Herk 1, Jef Huisman 1 and Petra M. Visser 1,* 1 Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, 1090 GE Amsterdam, The Netherlands; [email protected] (T.P.); [email protected] (G.S.); [email protected] (G.M.); [email protected] (C.P.D.B.); [email protected] (P.C.S.); [email protected] (M.J.v.H.); [email protected] (J.H.) 2 Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherland Institute for Sea Research, 1790 AB Den Burg, The Netherlands * Correspondence: [email protected]; Tel.: +31-20-5257073 † These authors have contributed equally to this work. ‡ Current address: Department of Technology & Sources, Evides Water Company, 3006 AL Rotterdam, The Netherlands. Abstract: Applying low concentrations of hydrogen peroxide (H2O2) to lakes is an emerging method to mitigate harmful cyanobacterial blooms. While cyanobacteria are very sensitive to H2O2, little Citation: Piel, T.; Sandrini, G.; is known about the impacts of these H2O2 treatments on other members of the microbial com- Muyzer, G.; Brussaard, C.P.D.; Slot, munity. In this study, we investigated changes in microbial community composition during two P.C.; van Herk, M.J.; Huisman, J.; −1 lake treatments with low H2O2 concentrations (target: 2.5 mg L ) and in two series of controlled Visser, P.M.
    [Show full text]
  • Pioneering Soil Viromics to Elucidate Viral Impacts on Soil Ecosystem Services
    Pioneering Soil Viromics to Elucidate Viral Impacts on Soil Ecosystem Services DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Gareth Trubl Graduate Program in Microbiology The Ohio State University 2018 Dissertation Committee: Virginia Rich, Advisor Matthew Sullivan, Co-Advisor Kelly Wrighton Matthew Anderson Copyrighted by Gareth Trubl 2018 Abstract Permafrost contains 30–50% of global soil carbon (C) and is rapidly thawing. While the fate of this C is unknown, it will be shaped in part by microbes and their associated viruses, which modulate microbial activities via mortality and metabolic control. To date, viral research in soils has been outpaced by that in aquatic environments due to the technical challenges of accessing soil viruses, compounded by the dramatic physicochemical heterogeneity in soils. The Stordalen Mire long-term ecological field site in Arctic Sweden encompasses a mosaic of natural permafrost thaw stages, and has been well characterized biogeochemically and microbiologically, making it an ideal site to characterize the soil virosphere and its potential impacts on the C cycle. A viral resuspension protocol was developed to generate quantitatively- amplified dsDNA viromes. The protocol yielded ~108 virus-like particles (VLPs) g−1 of soil across three thaw-stage habitats, and seven resulting viromes yielded 53 vOTUs. Viral-specific bioinformatics methods were used to recover viral populations, define their gene content, connect them to other related viruses (globally) and potential hosts (locally). Only 15% of these vOTUs had genetic similarity to publicly available viruses in the RefSeq database, and ∼30% of the genes could be annotated, supporting the concept of soils as reservoirs of substantial undescribed viral genetic diversity.
    [Show full text]
  • Viruses-10-00676
    UvA-DARE (Digital Academic Repository) Influence of irradiance and temperature on the virus MpoV-45T infecting the Arctic picophytoplankter Micromonas polaris Piedade, G.J.; Wesdorp, E.M.; Montenegro-Borbolla , E.; Maat, D.S.; Brussaard, C.P.D. DOI 10.3390/v10120676 Publication date 2018 Document Version Final published version Published in Viruses License CC BY Link to publication Citation for published version (APA): Piedade, G. J., Wesdorp, E. M., Montenegro-Borbolla , E., Maat, D. S., & Brussaard, C. P. D. (2018). Influence of irradiance and temperature on the virus MpoV-45T infecting the Arctic picophytoplankter Micromonas polaris. Viruses, 10(12), [676]. https://doi.org/10.3390/v10120676 General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. UvA-DARE is a service provided by the library of the University of Amsterdam (https://dare.uva.nl) Download date:24 Sep 2021 viruses Article Influence of Irradiance and Temperature on the Virus MpoV-45T Infecting the Arctic Picophytoplankter Micromonas polaris Gonçalo J.
    [Show full text]
  • Virally Induced Mortality of Phaeocystis Globosa During Two Spring Blooms in Temperate Coastal Waters
    AQUATIC MICROBIAL ECOLOGY Vol. 44: 207–217, 2006 Published October 10 Aquat Microb Ecol Virally induced mortality of Phaeocystis globosa during two spring blooms in temperate coastal waters Anne-Claire Baudoux, Anna A. M. Noordeloos, Marcel J. W. Veldhuis, Corina P. D. Brussaard* Department of Biological Oceanography, Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, The Netherlands ABSTRACT: This study reports virally mediated mortality rates of Phaeocystis globosa single cells in the southern North Sea during 2 consecutive spring blooms (2003 and 2004). An adapted dilution method was used to estimate viral lysis and microzooplankton grazing simultaneously. Parallel dilu- tion experiments were performed with 30 kDa ultrafiltrate (virus and grazer-free diluent) and 0.2 µm filtered seawater (grazer-free, but virus-containing diluent). Specific viral lysis rates were calculated from the difference in P. globosa growth rates between the 2 dilution series after 24 h incubation under natural conditions. The validity of this method was tested using a culture of P. globosa infected with a known P. globosa virus (PgV). The field data show that virally induced mortality can be a sub- stantial loss factor for P. globosa single cells (up to 0.35 d–1), comparable to that due to microzoo- plankton grazing (up to 0.4 d–1). Viral lysis was the major cause of total P. globosa cell lysis. Assum- ing no loss due to sinking, viral lysis accounted for 5 to 66% of the total mortality of P. globosa single cells. Viral lysis and total putative PgV abundance increased concomitantly with abundance of P.
    [Show full text]
  • Article Size Distribution and A
    EGU Journal Logos (RGB) Open Access Open Access Open Access Advances in Annales Nonlinear Processes Geosciences Geophysicae in Geophysics Open Access Open Access Natural Hazards Natural Hazards and Earth System and Earth System Sciences Sciences Discussions Open Access Open Access Atmospheric Atmospheric Chemistry Chemistry and Physics and Physics Discussions Open Access Open Access Atmospheric Atmospheric Measurement Measurement Techniques Techniques Discussions Open Access Biogeosciences, 10, 719–731, 2013 Open Access www.biogeosciences.net/10/719/2013/ Biogeosciences doi:10.5194/bg-10-719-2013 Biogeosciences Discussions © Author(s) 2013. CC Attribution 3.0 License. Open Access Open Access Climate Climate of the Past of the Past Discussions Arctic microbial community dynamics Open Access Open Access Earth System influenced by elevated CO2 levels Earth System Dynamics 1 1 1 1 2 Dynamics2 2 C. P. D. Brussaard , A. A. M. Noordeloos , H. Witte , M. C. J. Collenteur , K. Schulz , A. Ludwig , and U. Riebesell Discussions 1Department of Biological Oceanography, NIOZ - Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands Open Access Open Access 2Helmholtz Centre for Ocean Research (GEOMAR), Kiel, Germany Geoscientific Geoscientific Instrumentation Instrumentation Correspondence to: C. P. D. Brussaard ([email protected]) Methods and Methods and Received: 10 August 2012 – Published in Biogeosciences Discuss.: 12 September 2012 Data Systems Data Systems Revised: 21 December 2012 – Accepted: 2 January 2013 – Published: 1 February 2013 Discussions Open Access Open Access Geoscientific Geoscientific Abstract. The Arctic Ocean ecosystem is particularly vul- surface water pH values were still 8.2 just prior to the indus- Model Development nerable to ocean acidification (OA) related alterations due to trial era, they areModel 8.11 at presentDevelopment and anticipated to reach 7.8 Discussions the relatively high CO2 solubility and low carbonate satura- in the year 2100 (The Royal Society, 2005).
    [Show full text]
  • Isolation and Characterization of a Double Stranded DNA Megavirus Infecting the Toxin-Producing Haptophyte Prymnesium Parvum
    viruses Article Isolation and Characterization of a Double Stranded DNA Megavirus Infecting the Toxin-Producing Haptophyte Prymnesium parvum Ben A. Wagstaff 1, Iulia C. Vladu 1, J. Elaine Barclay 1, Declan C. Schroeder 2, Gill Malin 3 and Robert A. Field 1,* 1 Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK; [email protected] (B.A.W.); [email protected] (I.C.V.); [email protected] (J.E.B.) 2 Marine Biological Association of the UK, Plymouth PL1 2PB, UK; [email protected] 3 Centre for Ocean and Atmospheric Studies, School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK; [email protected] * Correspondence: rob.fi[email protected]; Tel.: +44-1603-450720 Academic Editors: Mathias Middelboe and Corina Brussaard Received: 29 January 2017; Accepted: 27 February 2017; Published: 9 March 2017 Abstract: Prymnesium parvum is a toxin-producing haptophyte that causes harmful algal blooms globally, leading to large-scale fish kills that have severe ecological and economic implications. For the model haptophyte, Emiliania huxleyi, it has been shown that large dsDNA viruses play an important role in regulating blooms and therefore biogeochemical cycling, but much less work has been done looking at viruses that infect P. parvum, or the role that these viruses may play in regulating harmful algal blooms. In this study, we report the isolation and characterization of a lytic nucleo-cytoplasmic large DNA virus (NCLDV) collected from the site of a harmful P. parvum bloom. In subsequent experiments, this virus was shown to infect cultures of Prymnesium sp.
    [Show full text]
  • Corina P.D. Brussaard, Jérôme P. Payet, Christian Winter, and Markus
    MANUAL of MAVE Chapter 11, 2010, 102–109 AQUATIC VIRAL ECOLOGY © 2010, by the American Society of Limnology and Oceanography, Inc. Quantification of aquatic viruses by flow cytometry Corina P. D. Brussaard1*, Jérôme P. Payet2, Christian Winter 3, and Markus G. Weinbauer 4 1NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands 2Department of Earth and Ocean Sciences, University of British Columbia, Vancouver, BC, Canada 3Department of Marine Biology, University of Vienna, Vienna, Austria 4Microbial Ecology & Biogeochemistry Group, Université Pierre et Marie Curie-Paris 6, and CNRS, Laboratoire d’Océanographie de Villefranche, Villefranche-sur-Mer, France Abstract For many laboratories, flow cytometry is becoming the routine method for quantifying viruses in aquatic sys- tems because of its high reproducibility, high sample throughput, and ability to distinguish several subpopula- tions of viruses. Comparison of viral counts between flow cytometry and epifluorescence microscopy typically shows slopes that are statistically not distinguishable from 1, thus confirming the usefulness of flow cytometry. Here we describe in detail all steps in the procedure, discuss potential problems, and offer solutions. Introduction ence of the appropriate host and approaches based on molec- ular markers have proven very useful (Larsen et al. 2007; Mühling Viruses are the most numerous biological entities in aquatic et al. 2005; Schroeder et al. 2003; Short and Suttle 2002). To ecosystems, typically on the order of 107 mL–1 (Suttle 2007). count total free viruses in aqueous samples, transmission elec- Many studies have contributed to the acknowledgment that tron microscopy (TEM), epifluorescence microscopy (EFM), viruses are active and diverse players in freshwater and marine and flow cytometry (FCM) are most often used.
    [Show full text]
  • Characterization and Temperature Dependence of Arctic Micromonas Polaris Viruses
    viruses Article Characterization and Temperature Dependence of Arctic Micromonas polaris Viruses Douwe S. Maat 1,†, Tristan Biggs 1,†, Claire Evans 1,2, Judith D. L. van Bleijswijk 1, Nicole N. van der Wel 3, Bas E. Dutilh 4,5 and Corina P. D. Brussaard 1,* 1 Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, and University of Utrecht, P.O. Box 59, 1790 AB Den Burg, Texel, The Netherlands; [email protected] (D.S.M.); [email protected] (T.B.); [email protected] (C.E.); [email protected] (J.D.L.v.B.) 2 Ocean Biogeochemistry & Ecosystems Research Group, National Oceanography Centre, Southampton, European Way, Southampton SO14 3ZH, UK 3 Electron Microscopy Center Amsterdam, Department of Cell Biology and Histology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands; [email protected] 4 Theoretical Biology and Bioinformatics, Utrecht University, 3584 CH Utrecht, The Netherlands; [email protected] 5 Centre for Molecular and Biomolecular Informatics, Radboud University Medical Centre, 6525 GA Nijmegen, The Netherlands * Correspondence: [email protected]; Tel.: +31-(0)222-369513 † Joint first authors. Academic Editor: Eric O. Freed Received: 4 March 2017; Accepted: 25 May 2017; Published: 2 June 2017 Abstract: Global climate change-induced warming of the Artic seas is predicted to shift the phytoplankton community towards dominance of smaller-sized species due to global warming. Yet, little is known about their viral mortality agents despite the ecological importance of viruses regulating phytoplankton host dynamics and diversity. Here we report the isolation and basic characterization of four prasinoviruses infectious to the common Arctic picophytoplankter Micromonas.
    [Show full text]
  • Antarctic Phytoplankton Community Composition and Size Structure: Importance of Ice Type and Temperature As Regulatory Factors
    Polar Biology https://doi.org/10.1007/s00300-019-02576-3 ORIGINAL PAPER Antarctic phytoplankton community composition and size structure: importance of ice type and temperature as regulatory factors T. E. G. Biggs1,2 · S. Alvarez‑Fernandez3 · C. Evans4 · K. D. A. Mojica5 · P. D. Rozema6 · H. J. Venables7 · D. W. Pond8 · C. P. D. Brussaard1 Received: 6 December 2018 / Revised: 4 July 2019 / Accepted: 28 August 2019 © The Author(s) 2019 Abstract Climate change at the Western Antarctic Peninsula (WAP) is predicted to cause major changes in phytoplankton community composition, however, detailed seasonal feld data remain limited and it is largely unknown how (changes in) environmental factors infuence cell size and ecosystem function. Physicochemical drivers of phytoplankton community abundance, taxo- nomic composition and size class were studied over two productive austral seasons in the coastal waters of the climatically sensitive WAP. Ice type (fast, grease, pack or brash ice) was important in structuring the pre-bloom phytoplankton community as well as cell size of the summer phytoplankton bloom. Maximum biomass accumulation was regulated by light and nutrient availability, which in turn were regulated by wind-driven mixing events. The proportion of larger-sized (> 20 µm) diatoms increased under prolonged summer stratifcation in combination with frequent and moderate-strength wind-induced mixing. Canonical correspondence analysis showed that relatively high temperature was correlated with nano-sized cryptophytes, whereas prymnesiophytes (Phaeocystis antarctica) increased in association with high irradiance and low salinities. During autumn of Season 1, a large bloom of 4.5-µm-sized diatoms occurred under conditions of seawater temperature > 0 °C and relatively high light and phosphate concentrations.
    [Show full text]
  • Viral Regulation of Nutrient Assimilation by Algae and Prokaryotes
    Viral regulation of nutrient assimilation by algae and prokaryotes Dissertation zur Erlangung des Doktorgrades der Naturwissenschaften - Dr. rer. nat. - dem Fachbereich Geowissenschaften der Universität Bremen vorgelegt von Abdul Rahiman Sheik Bremen, Oktober 2012 Die vorliegende Arbeit wurde in der Zeit von April 2009 bis September 2012 am Max Planck Institut für Marine Mikrobiologie angefertigt. 1. Gutachter: Prof. Dr. Marcel Kuypers 2. Gutachterin: Dr. Corina Brussaard Tag des Promotionskolloquiums: 10. Dezember 2012 Summary Viruses are the most abundant entities in the ocean and represent a large portion of ‘lifes’ genetic diversity. As mortality agents, viruses catalyze transformations of particulate matter to dissolved forms. This viral catalytic activity may influence the microbial community structure and affect the flow of critical elements in the sea. However, the extent to which viruses mediate bacterial diversity and biogeochemical processes is poorly studied. The current thesis, using a single cell approach, provides rare and novel insights in to how viral infections of algae influence host carbon assimilation. Furthermore this thesis details how cell lysis by viruses regulates the temporal bacterial community structure and their subsequent uptake of algal viral lysates. Chapter 2 shows how viruses impair the release of the star-like structures of virally infected Phaeocystis globosa cells. The independent application of high resolution single cells techniques using atomic force microscopy (AFM) visualized the unique host morphological feature due to viral infection and nanoSIMS imaging quantified the impact of viral infection on the host carbon assimilation. Prior to cell lysis, substantial amounts of newly produced viruses (~ 68%) were attached to P. globosa cells. The hypothesis that impediment of star-like structures in infected P.
    [Show full text]
  • Validation of Stratification-Driven Phytoplankton Biomass and Nutrient Concentrations in the Northeast Atlantic Ocean As Simulat
    geosciences Article Validation of Stratification-Driven Phytoplankton Biomass and Nutrient Concentrations in the Northeast Atlantic Ocean as Simulated by EC-Earth Nomikos Skyllas 1 , Richard Bintanja 2,3, Anita G. J. Buma 3, Corina P. D. Brussaard 1 , 4, 4 3, Matthias Gröger y , Jenny Hieronymus and Willem H. van de Poll * 1 Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, and Utrecht University, 1790 AB Den Burg, The Netherlands; [email protected] (N.S.); [email protected] (C.P.D.B.) 2 Royal Netherlands Meteorological Institute (KNMI), 3731 GA De Bilt, The Netherlands; [email protected] 3 Department of Ocean Ecosystems, Energy and Sustainability Research Institute Groningen, University of Groningen, 9747 AG Groningen, The Netherlands; [email protected] 4 Swedish Meteorological and Hydrological Institute, SMHI SE-601 76 Norrköping, Sweden; [email protected] (M.G.); [email protected] (J.H.) * Correspondence: [email protected] Current address: Department of Physical Oceanography and Instrumentation, Leibniz Institute for Baltic Sea y Research Warnemünde, 18119 Rostock, Germany. Received: 26 September 2019; Accepted: 17 October 2019; Published: 21 October 2019 Abstract: We validated simulations of the Earth system model (ESM) EC-Earth-NEMO of present-day temperature, salinity, nutrient, and chlorophyll a profiles with in situ observations in the Northeast Atlantic Ocean (29–63º N). Simulations with standard parametrization (run 1) and improved parametrization of vertical mixing (run 2) were compared. Run 1 showed shallower mixed layer depths (MLDs) in spring as compared to observations owing to lower salinities in the upper 200 m of the subpolar North Atlantic (>55º N).
    [Show full text]