DOCSLIB.ORG

Emiliania Huxleyi L

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Emiliania Huxleyi L Diversity of coccolithophores from the Mediterranean sea during the BOUM cruise Bendif E-M., Cros L., Beaufort L., Probert, I., Young, J., and De Vargas. EPPO « Evolution du Plancton et Paléo Océans » UMR 7144, Station Biologique de Roscoff, Bretagne, France Coccolithphores Calcifying microalgae Range size: 3 to 40µm J. Young Implication of coccolithophores in global process O2 Production and CO 2 sequestration Photosynthesis Coccolithogenesis CaCO 3 sedimentation Role on ocean carbonate system DMS Local cooling effect O2 DMS production and Clouds nucleation CO 2 (Bloom auto regulation) Targeting keys groups as a proxies to study effect and organsim responses to the elevation of pCO2 Coccolithophore bloom BOUM - Sampled Stations 19 15 7 Sampling BIO B (10 stations) Parameters: CLHC MAHD AQAQ SEMM Morphogenetic Automatic (=SEMD) (+DCOC) quantitative quantitative SEM analyses of LSU rDNA clone analyses of analyses of coccolithophores libraries of haptophytes coccolithophores - (Morphology and haptophytes and diversity - CODFISH SYRACO Diversity) coccolithophores In progress In progress Analyses in Not processed yet Collaboration with Collaboration with progress Luc Beaufort Lluisa Cros (targeting key- (Cerege Aix-en- (University of groups with Provence) Barcelona) specific primers, DNA extraction) Polycrater sp. L. Cros Umbilicosphaera hulburtiana L. Cros Emiliania huxleyi L. Cros Syracosphaera pulchra L. Cros Calcidiscus leptoporus L. Cros Rhabdosphaera klaviga L. Cros Coronosphaera binodata L. Cros Periphyllophora mirabilis Syracosphaera anthos L. Cros • example of Coccolithophore used as a proxy: – Emiliania huxleyi – Preliminary study A MORPHO-GENETIC ASSESSMENT OF MICRO-EVOLUTION IN EXTANT NOELAERHABDACEAN COCCOLITHOPHORES El Mahdi Bendif 1, Ian Probert 1, Kyoko Hagino-Tomioka 2, Kazuhiro Kogame 2 , Yoshihito Takano 2, Jeremy Young 3 and Colomban de Vargas 1 1CNRS, UMR 7144 & UPMC Univ Paris 06, Equipe EPPO - Evolution du Plancton et Paléo-Océans, Station Biologique de Roscoff, 29682, France 2Division of Biological Sciences, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan 3Palaeontology Dept., the Natural History Museum, Cromwell Road, London, SW7 5BD, UK • Order Isochrysidales • Family ISOCHRYSIDACEAE Non coccolithophores • Genus Chrysotila • Chrysotila lamellosa • Chrysotila sipitata • Genus Dicrateria • Dicrateria gilva • Dicrateria inornata • Genus Isochrysis • Isochrysis galbana • Isochrysis littoralis • Family NOËLAERHABDACEAE Coccolithophores • Genus Emiliania • Emiliania huxleyi • Genus Gephyrocapsa • Gephyrocapsa caribbeanica • Gephyrocapsa crassipons • Gephyrocapsa ericsonii Ehux Goce • Gephyrocapsa muellerae • Gephyrocapsa oceanica • Gephyrocapsa ornata • Genus Reticulofenestra • Reticulofenestra maceria Emiliania fossil record . Ehux originated very recently, ~250,000 years ago. On the right, abundance (% total calcareous nannoplankton) of Ehux (sensu lato ) skeletons in deep-sea sediments over the last 800,000 years (modified, Hine and Weaver 1998). The origin of modern humans is indicated for comparison. + Used as proxy for paleoclimate modelling (abundance seems be linked with glaciations events) + Used in paleostratigraphy to estimate Geologic periods during Quaternary Cultures Sampling (Niskin bottle or 5 µm net at 5 m depth) Media K/5, K/5 + soil extract + germanium Isolation Collection Molecular caracterisation barcoding: 28S + cox1 ......... Morphologic caracterisation • 53 strains of Noelhearhabdaceae – 13 Ehux from station C at DCM (first Ehux strains from east MS) – 15 Ehux in station B at 5m – 4 Ehux from station 19 at DCM – 9 Goce in station A at the DCM – 8 Ehux in station A at 5m – 4 Ehux in station A at DCM Good references for previous work Cold and temperate Ehux Goce Station C strain Station B Station 19 Pacific Ehux Station A strains Eastern MS Ehux specific molecular signature ?.
Load more

Recommended publications
  • University of Oklahoma
    UNIVERSITY OF OKLAHOMA GRADUATE COLLEGE MACRONUTRIENTS SHAPE MICROBIAL COMMUNITIES, GENE EXPRESSION AND PROTEIN EVOLUTION A DISSERTATION SUBMITTED TO THE GRADUATE FACULTY in partial fulfillment of the requirements for the Degree of DOCTOR OF PHILOSOPHY By JOSHUA THOMAS COOPER Norman, Oklahoma 2017 MACRONUTRIENTS SHAPE MICROBIAL COMMUNITIES, GENE EXPRESSION AND PROTEIN EVOLUTION A DISSERTATION APPROVED FOR THE DEPARTMENT OF MICROBIOLOGY AND PLANT BIOLOGY BY ______________________________ Dr. Boris Wawrik, Chair ______________________________ Dr. J. Phil Gibson ______________________________ Dr. Anne K. Dunn ______________________________ Dr. John Paul Masly ______________________________ Dr. K. David Hambright ii © Copyright by JOSHUA THOMAS COOPER 2017 All Rights Reserved. iii Acknowledgments I would like to thank my two advisors Dr. Boris Wawrik and Dr. J. Phil Gibson for helping me become a better scientist and better educator. I would also like to thank my committee members Dr. Anne K. Dunn, Dr. K. David Hambright, and Dr. J.P. Masly for providing valuable inputs that lead me to carefully consider my research questions. I would also like to thank Dr. J.P. Masly for the opportunity to coauthor a book chapter on the speciation of diatoms. It is still such a privilege that you believed in me and my crazy diatom ideas to form a concise chapter in addition to learn your style of writing has been a benefit to my professional development. I’m also thankful for my first undergraduate research mentor, Dr. Miriam Steinitz-Kannan, now retired from Northern Kentucky University, who was the first to show the amazing wonders of pond scum. Who knew that studying diatoms and algae as an undergraduate would lead me all the way to a Ph.D.
    [Show full text]
  • Seasonal and Depth Variations in Molecular and Isotopic Alkenone Composition of Sinking Particles from the Western Title North Pacific
    Seasonal and depth variations in molecular and isotopic alkenone composition of sinking particles from the western Title North Pacific Author(s) Yamamoto, Masanobu; Shimamoto, Akifumi; Fukuhara, Tatsuo; Naraoka, Hiroshi; Tanaka, Yuichiro; Nishimura, Akira Deep Sea Research Part I : Oceanographic Research Papers, 54(9), 1571-1592 Citation https://doi.org/10.1016/j.dsr.2007.05.012 Issue Date 2007-09 Doc URL http://hdl.handle.net/2115/28776 Type article (author version) File Information DSR54-9.pdf Instructions for use Hokkaido University Collection of Scholarly and Academic Papers : HUSCAP Seasonal and depth variations in molecular and isotopic alkenone composition of sinking particles from the western North Pacific Masanobu Yamamoto1,*, Akifumi Shimamoto2, Tatsuo Fukuhara2, Hiroshi Naraoka3, Yuichiro Tanaka4 and Akira Nishimura4 1Faculty of Environmental Earth Science, Hokkaido University, Sapporo 060-0810, Japan. 2The General Environmental Technos Co., LTD., Osaka 541-0052, Japan. 3Department of Earth Sciences, Okayama University, Okayama 700-8530, Japan. 4National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8567, Japan *Corresponding author; [email protected] Abstract: Seasonal and depth variations in alkenone flux and molecular and isotopic composition of sinking particles were examined using a 21-month time-series sediment trap experiment at a mooring station WCT-2 (39°N, 147°E) in the mid-latitude NW Pacific to assess the influences of seasonality, production depth, and degradation in the K’ water column on the alkenone unsaturation index U 37. Analysis of the underlying sediments was also conducted to evaluate the effects of alkenone degradation at the 1 K’ K’ water-sediment interface on U 37.
    [Show full text]
  • The Ecology and Glycobiology of Prymnesium Parvum
    The Ecology and Glycobiology of Prymnesium parvum Ben Adam Wagstaff This thesis is submitted in fulfilment of the requirements of the degree of Doctor of Philosophy at the University of East Anglia Department of Biological Chemistry John Innes Centre Norwich September 2017 ©This copy of the thesis has been supplied on condition that anyone who consults it is understood to recognise that its copyright rests with the author and that use of any information derived there from must be in accordance with current UK Copyright Law. In addition, any quotation or extract must include full attribution. Page | 1 Abstract Prymnesium parvum is a toxin-producing haptophyte that causes harmful algal blooms (HABs) globally, leading to large scale fish kills that have severe ecological and economic implications. A HAB on the Norfolk Broads, U.K, in 2015 caused the deaths of thousands of fish. Using optical microscopy and 16S rRNA gene sequencing of water samples, P. parvum was shown to dominate the microbial community during the fish-kill. Using liquid chromatography-mass spectrometry (LC-MS), the ladder-frame polyether prymnesin-B1 was detected in natural water samples for the first time. Furthermore, prymnesin-B1 was detected in the gill tissue of a deceased pike (Exos lucius) taken from the site of the bloom; clearing up literature doubt on the biologically relevant toxins and their targets. Using microscopy, natural P. parvum populations from Hickling Broad were shown to be infected by a virus during the fish-kill. A new species of lytic virus that infects P. parvum was subsequently isolated, Prymnesium parvum DNA virus (PpDNAV-BW1).
    [Show full text]
  • Co-Variation of Metabolic Rates and Cell-Size in Coccolithophores” by G
    Open Access Biogeosciences Discuss., 12, C2737–C2744, 2015 www.biogeosciences-discuss.net/12/C2737/2015/ Biogeosciences © Author(s) 2015. This work is distributed under Discussions the Creative Commons Attribute 3.0 License. Interactive comment on “Co-variation of metabolic rates and cell-size in coccolithophores” by G. Aloisi Anonymous Referee #2 Received and published: 11 June 2015 GENERAL COMMENTS The paper by Aloisi presents an important analysis of a database of cell volume and cellular rates of growth, calcification and photosynthesis in terms of examining allo- metric and ecological patterns in coccolithophore physiology. The insights gained are intriguing and of great interest, as well as being very relevant to current studies on coc- colithophore ecophysiology. However, there are a few issues that would improve the paper and avoid any potential misunderstandings. Firstly, the paper contains a number of sweeping statements (e.g. coccolithophores do x) that are based on our incredibly detailed understanding of E. huxleyi physiology, but we lack the same level of understanding across the other 200+ species of coc- colithophores with which to expand such statements across the entire group. This E. C2737 huxleyi bias is evident in the database used in the paper, where 82% of the measure- ments of cell size come from E. huxleyi experiments alone. This bias should be clearly stated, addressed and made very obvious in the paper’s abstract, scope and conclu- sions - leading to a drive for future experimentalists and observationists to collect these types of data in the future in order to further examine the patterns seen here. Another important caveat is the normalisation of the growth rates across the day- lengths used in the different experiments.
    [Show full text]
  • On the Ultrastructure of Gephyrocapsa Oceanica (Haptophyta) Life Stages
    Cryptogamie, Algologie, 2014, 35 (4): 379-388 © 2014 Adac. Tous droits réservés On the ultrastructure of Gephyrocapsa oceanica (Haptophyta) life stages El Mahdi BENDIFa* & Jeremy YOUNGb aMarine Biological Association of the UK, Plymouth, UK bDepartment of Earth Sciences, University College, London, UK Résumé – Gephyrocapsa oceanica est une espèce cosmopolite de coccolithophores appar- tenant à la famille des Noëlaerhabdaceae dans l’ordre des Isochrysidales. Exclusivement pélagique, G. oceanica est fréquemment retrouvée dans les océans modernes ainsi que dans les sédiments fossiles. Aussi, elle est apparentée à Emiliania huxleyi chez qui un cycle haplodiplobiontique a été décrit, avec un stade diploïde ou les cellules sont immobiles et ornées de coccolithes, qui alterne avec un stade haploïde ou les cellules sont mobiles et ornées d’écailles organiques. Alors que la cytologie et l’ultrastructure des autres membres des Noëlaerhabdaceae n’ont jamais été étudié, ces caractères peuvent être uniques au genre Emiliania ou communs à la famille. Dans cette étude, nous présentons pour la première fois l’ultrastructure des stades non-calcifiants mobiles et calcifiants immobile de G. oceanica. Nous n’avons pas retrouvé de différences ultrastructurales significatives entre ces deux morpho-espèces apparentées au niveau des stades diploïdes et haploïdes. Les similarités entre ces deux morpho-espèces démontrent une importante conservation des caractères cytologiques. Par ailleurs, nous avons discuté de la vraisemblance de ces résultats en rapport au contexte évolutif des Noelaerhabdaceae. Calcification / coccolithophores / Gephyrocapsa oceanica / cycle de vie / microscopie électronique à transmission / ultrastructure Abstract – Gephyrocapsa oceanica is a cosmopolitan bloom-forming coccolithophore species belonging to the haptophyte order Isochrysidales and family Noëlaerhabdaceae.
    [Show full text]
  • Physiology Regulates the Relationship Between Coccosphere Geometry and Growth-Phase in Coccolithophores Rosie M
    Biogeosciences Discuss., doi:10.5194/bg-2016-435, 2016 Manuscript under review for journal Biogeosciences Published: 1 November 2016 c Author(s) 2016. CC-BY 3.0 License. Physiology regulates the relationship between coccosphere geometry and growth-phase in coccolithophores Rosie M. Sheward1,2, Alex J. Poulton3, Samantha J. Gibbs1, Chris J. Daniels3, Paul R. Bown4 1 Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton, SO14 3ZH, United 5 Kingdom. 2 Institute of Geosciences, Goethe-University Frankfurt, 60438 Frankfurt am Main, Germany. 3 Ocean Biogeochemistry and Ecosystems, National Oceanography Centre, Southampton, SO14 3ZH, United Kingdom. 4 Department of Earth Sciences, University College London, Gower Street, London, WC1E 6BT, United Kingdom. 10 Correspondence to: Rosie M. Sheward ([email protected]) Abstract. Coccolithophores are an abundant phytoplankton group that exhibit remarkable diversity in their biology, ecology, and calcitic exoskeletons (coccospheres). Their extensive fossil record is testament to their important biogeochemical role and is a valuable archive of biotic responses to environmental change stretching back over 200 million years. However, to 15 realise the potential of this archive requires an understanding of the physiological processes that underpin coccosphere architecture. Using culturing experiments on four modern coccolithophore species (Calcidiscus leptoporus, Calcidiscus quadriperforatus, Helicosphaera carteri and Coccolithus braarudii) from three long-lived
    [Show full text]
  • Physiology Regulates the Relationship Between Coccosphere Geometry and Growth-Phase in Coccolithophores Rosie M
    Physiology regulates the relationship between coccosphere geometry and growth-phase in coccolithophores Rosie M. Sheward1,2, Alex J. Poulton3, Samantha J. Gibbs1, Chris J. Daniels3, Paul R. Bown4 1 Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton, SO14 3ZH, United 5 Kingdom. 2 Institute of Geosciences, Goethe-University Frankfurt, 60438 Frankfurt am Main, Germany. 3 Ocean Biogeochemistry and Ecosystems, National Oceanography Centre, Southampton, SO14 3ZH, United Kingdom. 4 Department of Earth Sciences, University College London, Gower Street, London, WC1E 6BT, United Kingdom. 10 Correspondence to: Rosie M. Sheward ([email protected]) Abstract. Coccolithophores are an abundant phytoplankton group that exhibit remarkable diversity in their biology, ecology, and calcitic exoskeletons (coccospheres). Their extensive fossil record is testament to their important biogeochemical role and is a valuable archive of biotic responses to environmental change stretching back over 200 million years. However, to 15 realise the full potential of this archive for (paleo-)biology and biogeochemistry requires an understanding of the physiological processes that underpin coccosphere architecture. Using culturing experiments on four modern coccolithophore species (Calcidiscus leptoporus, Calcidiscus quadriperforatus, Helicosphaera carteri and Coccolithus braarudii) from three long-lived families, we investigate how coccosphere architecture responds to shifts from exponential (rapid cell division) to stationary (slowed cell division) growth phases as cell physiology reacts to nutrient depletion. These 20 experiments reveal statistical differences in coccosphere size and the number of coccoliths per cell between these two growth phases, specifically that cells in exponential-phase growth are typically smaller with fewer coccoliths, whereas cells experiencing growth-limiting nutrient depletion have larger coccosphere sizes and greater numbers of coccoliths per cell.
    [Show full text]
  • Chemotaxonomic Fingerprints of Alkenones and Alkenoates In
    BPT25-P05 Room:Convention Hall Time:May 24 18:15-19:30 Chemotaxonomic fingerprints of alkenones and alkenoates in sediments of Lake Naga-ike on the Skarvsnes, Antarctica NAKAMURA, Hideto1¤ ; TAKEDA, Mayumi1 ; SAWADA, Ken1 ; TAKANO, Yoshinori2 1Hokkaido Univ., 2JAMSTEC K Long chain alkenones and alkenoates are widely distributed in marine sediments and their extent of unsaturation (U 37, K0 U 37) is extensively used for reconstruction of paleo sea surface temperature. Alkenones and related compounds have also been detected in various lakes, although there is a wide variation in alkenone compositions and the temperature calibrations between in- dividual settings. These variations probably reflect the difference in alkenone producing species (strains) in lakes. Indeed, recent DNA analysis revealed that multiple lineages of the order Isochrysidales are distributed among alkenone containing lakes, and is considered to be engaged in the alkenone production (2-3). Culture based investigation on temperature calibrations suggested the significant variation of calibrations among Isochrysidaceae species (Isochrysis galbana (4), Pseudoisochrysis paradoxa (5) and Chrysotila lamellosa (6)). Therefore, taxonomic identification of alkenone producers is essential to the proper selection of calibrations and thus lead to better application of alkenone paleothermometer in lakes. To elucidate chemotaxonomic characteristics of the compositions of alkenone and related compounds, we have been cul- tured 9 strains covering all 3 genera (Chrysotila , Isochrysis , Tisochrysis ) of the family Isochrysidaceae, and proposed that the lack of tetraunsaturated alkenones are common characteristic for genus Tisochrysis (7). In this study, cultured Isochrysidaceae strains as well as sediments of antarctic lake Naga-ike were examined further into the compositions of alkenones and alkenoates.
    [Show full text]
  • Lipids and Lipolytic Enzymes of the Microalga Isochrysis Galbana
    OCL 2017, 24(4), D407 © F. Hubert et al., published by EDP Sciences, 2017 DOI: 10.1051/ocl/2017023 OCL Oilseeds & fats Crops and Lipids Topical issue on: Available online at: LIPIDES DU FUTUR www.ocl-journal.org LIPIDS OF THE FUTURE PROCEEDINGS Lipids and lipolytic enzymes of the microalga Isochrysis galbana Florence Hubert, Laurent Poisson*, Céline Loiseau, Laurent Gauvry, Gaëlle Pencréac’h, Josiane Hérault and Françoise Ergan Laboratoire Mer, Molécules, Santé (EA 2160), Université du Maine, IUT de Laval, 52 rue des Drs Calmette et Guérin, BP 2045, 53020 Laval cedex, France Received 27 January 2017 – Accepted 21 April 2017 Topical Issue Abstract – Marine microalgae are now well-known for their ability to produce omega-3 long chain polyunsaturated fatty acids (PUFAs) such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Among these microalgae, Isochrysis galbana has received increasing interest especially because of its high DHA content and its common use in hatchery to feed fish larvae and clams. Moreover, lipolysis occurring from the biomass harvest stage suggests that I. galbana may contain lipolytic enzymes with potential interesting selectivities. For these reasons, the potential of this microalga for the production of valuable lipids and lipolytic enzymes was investigated. Lipid analysis revealed that DHA is mainly located at the sn-2 position of the phospholipids. Thus, I. galbana was considered as an interesting starting material for the lipase catalyzed production of 1-lyso-2-DHA-phospholipids which are considered as convenient vehicles for the conveyance of DHA to the brain. Lipids from I. galbana can also be used for the enzyme- catalyzed production of structured phospholipids containing one DHA and one medium chain fatty acid in order to combine interesting therapeutic and biological benefits.
    [Show full text]
  • Influence of Environmental Drivers and Potential Interactions on The
    fmicb-10-01067 May 14, 2019 Time: 16:36 # 1 ORIGINAL RESEARCH published: 15 May 2019 doi: 10.3389/fmicb.2019.01067 Influence of Environmental Drivers and Potential Interactions on the Distribution of Microbial Communities From Three Permanently Stratified Antarctic Lakes Wei Li1 and Rachael M. Morgan-Kiss2* 1 Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT, United States, 2 Department of Microbiology, Miami University, Oxford, OH, United States The McMurdo Dry Valley (MDV) lakes represent unique habitats in the microbial world. Perennial ice covers protect liquid water columns from either significant allochthonous inputs or seasonal mixing, resulting in centuries of stable biogeochemistry. Extreme Edited by: environmental conditions including low seasonal photosynthetically active radiation Krishnan Kottekkatu Padinchati, (PAR), near freezing temperatures, and oligotrophy have precluded higher trophic levels National Centre for Antarctic from the food webs. Despite these limitations, diverse microbial life flourishes in the and Ocean Research, India stratified water columns, including Archaea, bacteria, fungi, protists, and viruses. While a Reviewed by: Weidong Kong, few recent studies have applied next generation sequencing, a thorough understanding Institute of Tibetan Plateau Research of the MDV lake microbial diversity and community structure is currently lacking. Here (CAS), China Fabien Kenig, we used Illumina MiSeq sequencing of the 16S and 18S rRNA genes combined with The University of Illinois at Chicago, a microscopic survey of key eukaryotes to compare the community structure and United States potential interactions among the bacterial and eukaryal communities within the water *Correspondence: columns of Lakes Bonney (east and west lobes, ELB, and WLB, respectively) and Fryxell Rachael M.
    [Show full text]
  • Physiological Responses of Lipids in Emiliania Huxleyi and Gephyrocapsa Oceanica (Haptophyceae) to Growth Status and Their Implications for Alkenone Paleothermometry
    Organic Geochemistry 31 (2000) 799±811 www.elsevier.nl/locate/orggeochem Physiological responses of lipids in Emiliania huxleyi and Gephyrocapsa oceanica (Haptophyceae) to growth status and their implications for alkenone paleothermometry Masanobu Yamamoto a,*, Yoshihiro Shiraiwa b, Isao Inouye b aDepartment of Mineral and Fuel Resources, Geological Survey of Japan, 1-1-3 Higashi, Tsukuba, Ibaraki 305-8567, Japan bInstitute of Biological Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8572, Japan Received 4 January 2000; accepted 7 June 2000 (returned to author for revision 11 April 2000) Abstract The physiological responses of alkenone unsaturation indices to changes in growth status of E. huxleyi and G. oceanica strains isolated from a water sample of the NW Paci®c were examined using an isothermal batch culture K0 system. In both E. huxleyi and G. oceanica the unsaturation index U37 changed during the growth period, but the eects of this change were dierent. This suggests that genotypic variation rather than the adaptation of the strains to the geographical environment of the sampling location is a major factor in determining the physiological responses to K0 K0 U37. Changes of U37 were associated with those of the unsaturation indices of C38 and C39 alkenones, the abundance ratios of lower to higher homologues of alkenones, the abundance ratios of saturated to polyunsaturated n-fatty acids, the abundance ratio of ethyl alkenoate to alkenones, and sterol contents. These associations might be attributable to the physiological response of lipids for maintaining their ¯uidity. The degree of unsaturation both in alkenones and n- fatty acids increased at day 8, possibly due to nutrient depletion.
    [Show full text]
  • Edvardsen Et Al 2016 Diversity and Distribution of Haptophytes Revealed
    Perspectives in Phycology PrePub Article Published online April 2016 Diversity and distribution of haptophytes revealed by environmental sequencing and metabarcoding – a review Bente Edvardsen1*, Elianne Sirnæs Egge1, Daniel Vaulot2 1 University of Oslo, Department of Biosciences, P.O. Box 1066 Blindern, 0316 Oslo, Norway 2 Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 7144, Station Biologique, Place Georges Teissier, 29680 Roscoff, France * Corresponding author: [email protected] With 2 figures and 2 tables in the text and an electronic supplement Abstract: Microalgae of the division Haptophyta are a major component of the marine nanoplankton and present in all seas. They are important primary producers and grazers of picoplankton in the ocean, and their metabolic products can have an impact on global climate. Due to their small size, species are difficult to distinguish by microscopy, and knowledge on their diversity and distribution is incomplete. Environmental sequencing studies have revealed a high marine protist diversity. We review the current knowledge on diversity and distri- bution of haptophytes revealed by Sanger sequencing of clone libraries (environmental sequencing) and by high-throughput sequencing of amplicons (metabarcoding). We also discuss the methodology used. Finally, we provide a curated haptophyte reference 18S rRNA-gene database for future taxonomic assignment of environmental sequences and metabarcoding reads. Keywords: clone libraries, diversity, distribution, ecology, environmental sequencing, Haptophyta, high-throughput sequencing, novel lineages, metabarcoding, reference database Introduction populations of this important phytoplankton group is also to a large extent unclear. However, the use of molecular meth- Haptophytes are mostly single-celled nanophytoplankton ods, such as environmental sequencing and metabarcoding (usually 2–30 μm) and have a worldwide distribution.
    [Show full text]