DOCSLIB.ORG

Bioprospecting of Marine Fungi from the High Arctic

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Bioprospecting of Marine Fungi from the High Arctic Faculty of Biosciences, Fisheries and Economics The Norwegian College of Fishery Science Bioprospecting of marine fungi from the High Arctic A study of high latitude marine fungi from understudied taxa; bioactivity potential, taxonomy and genomics Ole Christian Hagestad A dissertation for the degree of Philosophiae Doctor April 2021 Cover page “A true teacher would never tell you what to do. But he would give you the knowledge with which you could decide what would be best for you to do.” ― Christopher Pike, Sati Bioprospecting of marine fungi from the High Arctic A study of high latitude marine fungi from understudied taxa; bioactivity potential, taxonomy and genomics A dissertation submitted in partial fulfilment of the requirement for the degree of Philosophiae Doctor. Ole Christian Hagestad Tromsø April 2021 The work presented in this thesis was carried out at the Norwegian College of Fishery Sciences (NFH), UiT – The Arctic University of Norway from January 2017 to April 2021. The work was funded by UiT - The Arctic University of Norway as an independent PhD position. i Summary Marine fungi comprise a group of organisms that have been overlooked for a long time. Research interest has increased with the realization of the important ecological role and rich chemistry of marine fungi. Marine fungi have yielded thousands of new natural products the last decade, but many taxa remain unstudied. Marine fungi from the Arctic have not been reported in literature in regard to bioprospecting campaigns and represent a novel source of natural products. The aim of this thesis is to assess the potential of Arctic marine fungi to produce bioactive secondary metabolites by fermentation and genome analysis. This was achieved in three steps. First, fungi were isolated from the Svalbard archipelago. The 20 isolates obtained were characterized based on molecular markers and their antibacterial activity was tested using an agar diffusion assay (Paper 1). Secondly, three distinct marine fungi were whole genome sequenced and characterized. One of the fungi represented a putatively novel species which was circumscribed based on morphology and phylogenetic inference (Paper 2). Finally, a metabolite from one fungus among the 20 obtained around Svalbard was isolated and the bioactivities characterized (Paper 3). In Paper 1, half of the fungal isolates showed activity against pathogenic bacteria and every third isolate represents potentially new species of fungi. Five of these isolates are strictly marine fungi belonging to the order of Lulworthiales. The study showed that the Arctic can yield novel marine fungal diversity that can be utilized in bioprospecting. For Paper 2, three marine fungi were whole genome sequenced and their biosynthetic gene clusters were characterized. Mapping of the biosynthetic gene clusters (BGCs) within the Emericellopsis genome confirmed the detection of the secondary metabolite helvolic acid produced during fermentation. The study revealed numerous unknown biosynthetic gene clusters and a range of carbohydrate active enzymes. Each of the three genomes provides the first genome of their respective taxa and can contribute to understanding their evolutionary adaption to the marine environment. In Paper 3, a novel compound from the fermentation broth of Mytilinidion sp. was isolated and its bioactivity was characterized using seven different bioactivity assays. The compound turned out to be a modified medium component with IC50 of 43 µM in an ACE- inhibitory assay. The compound was novel and this is the first report of its bioactivity. Molecular networking could perhaps have provided early indications that the compound was a modified medium component. ii Sammendrag Marin sopp er en gruppe av organismer som har vært oversett i lang tid. Interessen for marin sopp har steget i takt med økt forståelse for dens økologi og rike kjemi. Mange tusen nye naturprodukter har blitt beskrevet fra marin sopp de siste tiårene, men det er fremdeles mange grupper som ikke er godt studert. Marin sopp fra Arktis er ikke godt undersøkt i forbindelse med bioprospektering og representerer en ny kilde til naturprodukter. Målet med avhandlingen var å vurdere potensialet til Arktisk marin sopp for å produsere bioaktive metabolitter ved å bruke fermentering og genomanalyse. Dette ble gjennomført i tre steg. Først ble 20 marine sopp isolert i løpet av ett forskningstokt rundt Svalbard. Disse soppene ble karakterisert ved hjelp av molekylære markører og evnen til å produsere antibakterielle forbindelser ble undersøkt ved å bruke agar-diffusjons analyse (Artikkel 1). Det neste som ble gjort var at tre forskjellige marine sopp ble helgenomsekvensert og genomene ble karakterisert. En av soppene er antageligvis ny for vitenskapen og ble beskrevet basert på morfologisk og fylogenetisk analyser (Artikkel 2). Til sist ble ett stoff fra en av soppene fra Artikkel 1 isolert og bioaktiviteten til stoffet ble beskrevet (Artikkel 3). I den første artikkelen viste halvparten av de isolerte soppene antibakteriell aktivitet mot sykdomsfremkallende bakterier. Hvert tredje isolat representerer muligens nye arter basert på tilgjengelige referansesekvenser. Fem av de potensielt nye artene tilhører ordenen Lulworthiales som kun finnes i havet. Studien har vist at det er stort potensiale for å avdekke nye arter og at mange av disse viser evne til å produsere antibakterielle forbindelser. Dette viser at de kan utnyttes i bioprospektering. I Artikkel 2 ble tre ulike marine sopper helgenomsekvenseert og genomet ble karakterisert med tanke på hvilke biosyntetiske genklynger og karbohydrat-aktive enzymer som ble detektert. Karakteriseringen av genklyngene i Emericellopsis bekreftet deteksjonen av metabolitten helvolsyre som soppen produserte under fermentering. Studien avslørte mange ukjente genklynger og en rekke karbohydrat-aktive enzymer. De tre genomene er de første helsekvenserte genomene i deres respektive slekter og kan bidra til å gi ny kunnskap om de evolusjonære tilpasningene de har til det marine miljø. I den siste artikkelen ble ett ukjent stoff fra fermenteringen av Mytilinidion isolert. Bioaktiviteten til stoffet ble karakterisert ved hjelp av syv forskjellige bioaktivitetstester. Stoffet viste seg å være en delvis nedbrutt og modifisert mediekomponent som hadde en IC50 verdi på 42.3 µM i en ACE-inhiberingstest. Analyse ved hjelp av molekylært nettverk kunne kanskje avdekket at stoffet var relatert til dyrkningsmediumet. iii Acknowledgements Ever since I was a young boy I have always wanted to become a scientist and complete a PhD, mainly due to my parent’s supply of Science Illustrated1 issues. I was delighted when I got the opportunity to fulfil this dream at Marbio. I do not believe many research groups have the same team spirit on both professional and social levels as Marbio. First and foremost, I would like to express my thanks and highlight my main supervisor Dr. Teppo Rämä, who introduced me to the wonderful world of marine fungi, and was always prepared to answer questions even late in the weekend evenings. I am also deeply appreciative for my co-supervisors Prof. Dr. Jeanette H. Andersen, Prof. Dr. Espen H. Hansen and Dr. Bjørn Altermark. Your knowledge and feedback have been invaluable in pushing me forward and keeping me on track in this work. It was always possible for you to make me take a step back and look at the bigger picture when I got too hung up on details. Secondly, I would like to express my gratitude to all of my colleagues who have contributed to my work in different ways. Thanks to Marte Albrigtsen, Kirsti Helland, Dr. Kine Ø. Hansen, Dr. Johan Isaksson, Dr. Ruth Hendus-Altenburger, Dr, Chun Li and Dr. Sara Ullsten Wahlund for their work and help on bioassays, NMR, DNA extraction and PCR. I would also like to thank everyone else at Marbio and MarBank for making these four years as enjoyable as they were. A very heartfelt thanks to the other PhD students Marte, Yannik (now Dr.), Renate and Venke that shared the PhD life with me. A special thanks to Marte and André for proofreading my thesis. I also want to express my gratitude to the external collaborators that participated in parts of the project. A special thanks to Prof. Dr. Russell Cox and Dr. Eric Kuhnert at Leibniz Universität Hannover that allowed me to have a 3-months research stay in their group, digging into the biosynthetic potential of fungi (unfortunately cut short by corona). Thanks to Prof. Dr. Alan Dobson and his group at University College Cork for providing a deep-sea sponge isolate for our study and Lingwei Hou and Prof. Dr. Pedro Crous at Westerdijk Fungal Biodiversity Institute for providing assistance in morphological descriptions. Additionally, I would like to thank Prof. Dr. Joseph Spatafora and JGI collaborators in the 1KFG project that enabled the sequencing of the genomes. Lastly, I would like to thank all my friends and family for checking in on me, keeping me grounded, cheering me on and giving me support and encouragement through my PhD. Thank you for letting me share my happiness and frustrations with you. Thanks to everyone who has made this journey possible. I look forward to new adventures with you in the future! Tromsø, April 2021 Ole Christian Hagestad 1 Science Illustrated (Norwegian: Illustrert Vitenskap) is a popular science magazine that is given out monthly covering all areas of science. iv Abbreviations 18S Small ribosomal subunit 1KFG 1000 fungal genomes project 1D/2D NMR One and two dimensional nuclear magnetic resonance 28S Large ribosomal
Load more

Recommended publications
  • Development and Evaluation of Rrna Targeted in Situ Probes and Phylogenetic Relationships of Freshwater Fungi
    Development and evaluation of rRNA targeted in situ probes and phylogenetic relationships of freshwater fungi vorgelegt von Diplom-Biologin Christiane Baschien aus Berlin Von der Fakultät III - Prozesswissenschaften der Technischen Universität Berlin zur Erlangung des akademischen Grades Doktorin der Naturwissenschaften - Dr. rer. nat. - genehmigte Dissertation Promotionsausschuss: Vorsitzender: Prof. Dr. sc. techn. Lutz-Günter Fleischer Berichter: Prof. Dr. rer. nat. Ulrich Szewzyk Berichter: Prof. Dr. rer. nat. Felix Bärlocher Berichter: Dr. habil. Werner Manz Tag der wissenschaftlichen Aussprache: 19.05.2003 Berlin 2003 D83 Table of contents INTRODUCTION ..................................................................................................................................... 1 MATERIAL AND METHODS .................................................................................................................. 8 1. Used organisms ............................................................................................................................. 8 2. Media, culture conditions, maintenance of cultures and harvest procedure.................................. 9 2.1. Culture media........................................................................................................................... 9 2.2. Culture conditions .................................................................................................................. 10 2.3. Maintenance of cultures.........................................................................................................10
    [Show full text]
  • GFS Fungal Remains from Late Neogene Deposits at the Gray
    GFS Mycosphere 9(5): 1014–1024 (2018) www.mycosphere.org ISSN 2077 7019 Article Doi 10.5943/mycosphere/9/5/5 Fungal remains from late Neogene deposits at the Gray Fossil Site, Tennessee, USA Worobiec G1, Worobiec E1 and Liu YC2 1 W. Szafer Institute of Botany, Polish Academy of Sciences, Lubicz 46, PL-31-512 Kraków, Poland 2 Department of Biological Sciences and Office of Research & Sponsored Projects, California State University, Fullerton, CA 92831, U.S.A. Worobiec G, Worobiec E, Liu YC 2018 – Fungal remains from late Neogene deposits at the Gray Fossil Site, Tennessee, USA. Mycosphere 9(5), 1014–1024, Doi 10.5943/mycosphere/9/5/5 Abstract Interesting fungal remains were encountered during palynological investigation of the Neogene deposits at the Gray Fossil Site, Washington County, Tennessee, USA. Both Cephalothecoidomyces neogenicus and Trichothyrites cf. padappakarensis are new for the Neogene of North America, while remains of cephalothecoid fungus Cephalothecoidomyces neogenicus G. Worobiec, Neumann & E. Worobiec, fragments of mantle tissue of mycorrhizal Cenococcum and sporocarp of epiphyllous Trichothyrites cf. padappakarensis (Jain & Gupta) Kalgutkar & Jansonius were reported. Remains of mantle tissue of Cenococcum for the fossil state are reported for the first time. The presence of Cephalothecoidomyces, Trichothyrites, and other fungal remains previously reported from the Gray Fossil Site suggest warm and humid palaeoclimatic conditions in the southeast USA during the late Neogene, which is in accordance with data previously obtained from other palaeontological analyses at the Gray Fossil Site. Key words – Cephalothecoid fungus – Epiphyllous fungus – Miocene/Pliocene – Mycorrhizal fungus – North America – palaeoecology – taxonomy Introduction Fungal organic remains, usually fungal spores and dispersed sporocarps, are frequently found in a routine palynological investigation (Elsik 1996).
    [Show full text]
  • Based on a Newly-Discovered Species
    A peer-reviewed open-access journal MycoKeys 76: 1–16 (2020) doi: 10.3897/mycokeys.76.58628 RESEARCH ARTICLE https://mycokeys.pensoft.net Launched to accelerate biodiversity research The insights into the evolutionary history of Translucidithyrium: based on a newly-discovered species Xinhao Li1, Hai-Xia Wu1, Jinchen Li1, Hang Chen1, Wei Wang1 1 International Fungal Research and Development Centre, The Research Institute of Resource Insects, Chinese Academy of Forestry, Kunming 650224, China Corresponding author: Hai-Xia Wu ([email protected], [email protected]) Academic editor: N. Wijayawardene | Received 15 September 2020 | Accepted 25 November 2020 | Published 17 December 2020 Citation: Li X, Wu H-X, Li J, Chen H, Wang W (2020) The insights into the evolutionary history of Translucidithyrium: based on a newly-discovered species. MycoKeys 76: 1–16. https://doi.org/10.3897/mycokeys.76.58628 Abstract During the field studies, aTranslucidithyrium -like taxon was collected in Xishuangbanna of Yunnan Province, during an investigation into the diversity of microfungi in the southwest of China. Morpho- logical observations and phylogenetic analysis of combined LSU and ITS sequences revealed that the new taxon is a member of the genus Translucidithyrium and it is distinct from other species. Therefore, Translucidithyrium chinense sp. nov. is introduced here. The Maximum Clade Credibility (MCC) tree from LSU rDNA of Translucidithyrium and related species indicated the divergence time of existing and new species of Translucidithyrium was crown age at 16 (4–33) Mya. Combining the estimated diver- gence time, paleoecology and plate tectonic movements with the corresponding geological time scale, we proposed a hypothesis that the speciation (estimated divergence time) of T.
    [Show full text]
  • Thyronectria Revisited and Re-Instated
    Persoonia 33, 2014: 182–211 www.ingentaconnect.com/content/nhn/pimj RESEARCH ARTICLE http://dx.doi.org/10.3767/003158514X685211 Persistent hamathecial threads in the Nectriaceae, Hypocreales: Thyronectria revisited and re-instated W.M. Jaklitsch1, H. Voglmayr1,2 Key words Abstract Based on type studies and freshly collected material we here re-instate the genus Thyronectria (Nec- triaceae, Hypocreales). Species of this genus were recently for the most part classified in the genera Pleonectria act (Nectriaceae) or Mattirolia (Thyridiaceae), because Thyronectria and other genera had been identified as members Ascomycota of the Thyridiaceae due to the presence of paraphyses. Molecular phylogenies based on several markers (act, ITS, Hypocreales LSU rDNA, rpb1, rpb2, tef1, tub) revealed that the Nectriaceae contain members whose ascomata are characterised Mattirolia by long, more or less persistent, apical paraphyses. All of these belong to a single genus, Thyronectria, which thus Nectriaceae has representatives with hyaline, rosy, green or even dark brown and sometimes distoseptate ascospores. The new species type species of Thyronectria, T. rhodochlora, syn. T. patavina, syn. T. pyrrhochlora is re-described and illustrated. Pleonectria Within the Nectriaceae persistent, apical paraphyses are common in Thyronectria and rarely also occur in Nectria. pyrenomycetes The genus Mattirolia is revised and merged with Thyronectria and also Thyronectroidea is regarded as a synonym rpb1 of Thyronectria. The three new species T. asturiensis, T. caudata and T. obscura are added to the genus. Species rpb2 recently described in Pleonectria as well as some species of Mattirolia are combined in the genus, and a key to tef1 Thyronectria is provided. Five species are epitypified.
    [Show full text]
  • Aquatic Fungi of Iceland: Biflagellate Species
    ACTA NATURALIA ISLANDICA ISSUED BY THE ICELANDIC MUSEUM OF NATURAL HISTORY (NATTURUFR£BISTOFNUN iSLANDS) The :Museum has published two volumes of Acta Naturalia Islandica in the period 1946-1971, altogether issues. From 1972 each paper will appear under its own serial number, starting with no. 21. ACTA NATURALIA ISLANDICA is a series of original articles dealing with botany, geology and zoology of Iceland. ACTA NATURALIA ISLANDICA will be published preferably in English and will appear at irregular intervals. ACTA NATURALIA ISLANDICA may be obtained: 1: on basis of institutional exchange at Museum of Natural History, P. O. Box 5320, Reykjavik. 2: as separate copies on request (charges including mailing costs) at Snaebjorn J6nsson, The English Bookshop, Hafnarstraeti 4, Reykjaik, Iceland. AQUATIC FUNGI OF ICELAND: BIFLAGELLATE SPECIES Aquatic fungi of Iceland: Biflagellate specIes T. \iV. JOHNSON, Jr. Department of Botany, Duke University, Durham, North Carolina, U. S. A. A bstmct. Fifty six species of biflagellate (zo osporic) fungi are recorded from Iceland. These represent 16 genera in 9 families of 5 orders. Structural features and variational patterns of several taxa (and species complexes) are reported. A number of representatives have not been named, or are only provisionally identified, but they are usually accorded formal descrip­ tions and their taxonomy is discussed fully. Experimental work with isolates of Achlya and Aphanomyces resulted in culturally-induced structural modifications in certain groups of taxa. Save in a few cases where new inforamation has been brought to light, species previously reported from Iceland are noted merely by citaions to the literature. No new taxa are pro­ posed.
    [Show full text]
  • Illuminating Type Collections of Nectriaceous Fungi in Saccardo's
    Persoonia 45, 2020: 221–249 ISSN (Online) 1878-9080 www.ingentaconnect.com/content/nhn/pimj RESEARCH ARTICLE https://doi.org/10.3767/persoonia.2020.45.09 Illuminating type collections of nectriaceous fungi in Saccardo’s fungarium N. Forin1, A. Vizzini 2,3,*, S. Nigris1,4, E. Ercole2, S. Voyron2,3, M. Girlanda2,3, B. Baldan1,4,* Key words Abstract Specimens of Nectria spp. and Nectriella rufofusca were obtained from the fungarium of Pier Andrea Saccardo, and investigated via a morphological and molecular approach based on MiSeq technology. ITS1 and ancient DNA ITS2 sequences were successfully obtained from 24 specimens identified as ‘Nectria’ sensu Saccardo (including Ascomycota 20 types) and from the type specimen of Nectriella rufofusca. For Nectria ambigua, N. radians and N. tjibodensis Hypocreales only the ITS1 sequence was recovered. On the basis of morphological and molecular analyses new nomenclatural Illumina combinations for Nectria albofimbriata, N. ambigua, N. ambigua var. pallens, N. granuligera, N. peziza subsp. ribosomal sequences reyesiana, N. radians, N. squamuligera, N. tjibodensis and new synonymies for N. congesta, N. flageoletiana, Sordariomycetes N. phyllostachydis, N. sordescens and N. tjibodensis var. crebrior are proposed. Furthermore, the current classifi- cation is confirmed for Nectria coronata, N. cyanostoma, N. dolichospora, N. illudens, N. leucotricha, N. mantuana, N. raripila and Nectriella rufofusca. This is the first time that these more than 100-yr-old specimens are subjected to molecular analysis, thereby providing important new DNA sequence data authentic for these names. Article info Received: 25 June 2020; Accepted: 21 September 2020; Published: 23 November 2020. INTRODUCTION to orange or brown perithecia which do not change colour in 3 % potassium hydroxide (KOH) or 100 % lactic acid (LA) Nectria, typified with N.
    [Show full text]
  • The Holomorph of Parasarcopodium (Stachybotryaceae), Introducing P
    Phytotaxa 266 (4): 250–260 ISSN 1179-3155 (print edition) http://www.mapress.com/j/pt/ PHYTOTAXA Copyright © 2016 Magnolia Press Article ISSN 1179-3163 (online edition) http://dx.doi.org/10.11646/phytotaxa.266.4.2 The holomorph of Parasarcopodium (Stachybotryaceae), introducing P. pandanicola sp. nov. on Pandanus sp. SAOWALUCK TIBPROMMA1,2,3,4,5, SARANYAPHAT BOONMEE2, NALIN N. WIJAYAWARDENE2,3,5, SAJEEWA S.N. MAHARACHCHIKUMBURA6, ERIC H. C. McKENZIE7, ALI H. BAHKALI8, E.B. GARETH JONES8, KEVIN D. HYDE1,2,3,4,5,8 & ITTHAYAKORN PROMPUTTHA9,* 1Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Science, Kun- ming 650201, Yunnan, People’s Republic of China 2Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai, 57100, Thailand 3School of Science, Mae Fah Luang University, Chiang Rai, 57100, Thailand 4World Agroforestry Centre, East and Central Asia, Kunming 650201, Yunnan, P. R. China 5Mushroom Research Foundation, 128 M.3 Ban Pa Deng T. Pa Pae, A. Mae Taeng, Chiang Mai 50150, Thailand 6Department of Crop Sciences, College of Agricultural and Marine Sciences Sultan Qaboos University, P.O. Box 34, AlKhoud 123, Oman 7Manaaki Whenua Landcare Research, Private Bag 92170, Auckland, New Zealand 8Botany and Microbiology Department, College of Science, King Saud University, Riyadh, KSA 11442, Saudi Arabia 9Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand *Corresponding author: e-mail: [email protected] Abstract Collections of microfungi on Pandanus species (Pandanaceae) in Krabi, Thailand resulted in the discovery of a new species in the genus Parasarcopodium, producing both its sexual and asexual morphs.
    [Show full text]
  • Fungal Planet Description Sheets: 716–784 By: P.W
    Fungal Planet description sheets: 716–784 By: P.W. Crous, M.J. Wingfield, T.I. Burgess, G.E.St.J. Hardy, J. Gené, J. Guarro, I.G. Baseia, D. García, L.F.P. Gusmão, C.M. Souza-Motta, R. Thangavel, S. Adamčík, A. Barili, C.W. Barnes, J.D.P. Bezerra, J.J. Bordallo, J.F. Cano-Lira, R.J.V. de Oliveira, E. Ercole, V. Hubka, I. Iturrieta-González, A. Kubátová, M.P. Martín, P.-A. Moreau, A. Morte, M.E. Ordoñez, A. Rodríguez, A.M. Stchigel, A. Vizzini, J. Abdollahzadeh, V.P. Abreu, K. Adamčíková, G.M.R. Albuquerque, A.V. Alexandrova, E. Álvarez Duarte, C. Armstrong-Cho, S. Banniza, R.N. Barbosa, J.-M. Bellanger, J.L. Bezerra, T.S. Cabral, M. Caboň, E. Caicedo, T. Cantillo, A.J. Carnegie, L.T. Carmo, R.F. Castañeda-Ruiz, C.R. Clement, A. Čmoková, L.B. Conceição, R.H.S.F. Cruz, U. Damm, B.D.B. da Silva, G.A. da Silva, R.M.F. da Silva, A.L.C.M. de A. Santiago, L.F. de Oliveira, C.A.F. de Souza, F. Déniel, B. Dima, G. Dong, J. Edwards, C.R. Félix, J. Fournier, T.B. Gibertoni, K. Hosaka, T. Iturriaga, M. Jadan, J.-L. Jany, Ž. Jurjević, M. Kolařík, I. Kušan, M.F. Landell, T.R. Leite Cordeiro, D.X. Lima, M. Loizides, S. Luo, A.R. Machado, H. Madrid, O.M.C. Magalhães, P. Marinho, N. Matočec, A. Mešić, A.N. Miller, O.V. Morozova, R.P. Neves, K. Nonaka, A. Nováková, N.H.
    [Show full text]
  • Metabolites from Nematophagous Fungi and Nematicidal Natural Products from Fungi As an Alternative for Biological Control
    Appl Microbiol Biotechnol (2016) 100:3799–3812 DOI 10.1007/s00253-015-7233-6 MINI-REVIEW Metabolites from nematophagous fungi and nematicidal natural products from fungi as an alternative for biological control. Part I: metabolites from nematophagous ascomycetes Thomas Degenkolb1 & Andreas Vilcinskas1,2 Received: 4 October 2015 /Revised: 29 November 2015 /Accepted: 2 December 2015 /Published online: 29 December 2015 # The Author(s) 2015. This article is published with open access at Springerlink.com Abstract Plant-parasitic nematodes are estimated to cause Keywords Phytoparasitic nematodes . Nematicides . global annual losses of more than US$ 100 billion. The num- Oligosporon-type antibiotics . Nematophagous fungi . ber of registered nematicides has declined substantially over Secondary metabolites . Biocontrol the last 25 years due to concerns about their non-specific mechanisms of action and hence their potential toxicity and likelihood to cause environmental damage. Environmentally Introduction beneficial and inexpensive alternatives to chemicals, which do not affect vertebrates, crops, and other non-target organisms, Nematodes as economically important crop pests are therefore urgently required. Nematophagous fungi are nat- ural antagonists of nematode parasites, and these offer an eco- Among more than 26,000 known species of nematodes, 8000 physiological source of novel biocontrol strategies. In this first are parasites of vertebrates (Hugot et al. 2001), whereas 4100 section of a two-part review article, we discuss 83 nematicidal are parasites of plants, mostly soil-borne root pathogens and non-nematicidal primary and secondary metabolites (Nicol et al. 2011). Approximately 100 species in this latter found in nematophagous ascomycetes. Some of these sub- group are considered economically important phytoparasites stances exhibit nematicidal activities, namely oligosporon, of crops.
    [Show full text]
  • Molecular Systematics of the Marine Dothideomycetes
    available online at www.studiesinmycology.org StudieS in Mycology 64: 155–173. 2009. doi:10.3114/sim.2009.64.09 Molecular systematics of the marine Dothideomycetes S. Suetrong1, 2, C.L. Schoch3, J.W. Spatafora4, J. Kohlmeyer5, B. Volkmann-Kohlmeyer5, J. Sakayaroj2, S. Phongpaichit1, K. Tanaka6, K. Hirayama6 and E.B.G. Jones2* 1Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, 90112, Thailand; 2Bioresources Technology Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Thailand Science Park, Paholyothin Road, Khlong 1, Khlong Luang, Pathum Thani, 12120, Thailand; 3National Center for Biothechnology Information, National Library of Medicine, National Institutes of Health, 45 Center Drive, MSC 6510, Bethesda, Maryland 20892-6510, U.S.A.; 4Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, 97331, U.S.A.; 5Institute of Marine Sciences, University of North Carolina at Chapel Hill, Morehead City, North Carolina 28557, U.S.A.; 6Faculty of Agriculture & Life Sciences, Hirosaki University, Bunkyo-cho 3, Hirosaki, Aomori 036-8561, Japan *Correspondence: E.B. Gareth Jones, [email protected] Abstract: Phylogenetic analyses of four nuclear genes, namely the large and small subunits of the nuclear ribosomal RNA, transcription elongation factor 1-alpha and the second largest RNA polymerase II subunit, established that the ecological group of marine bitunicate ascomycetes has representatives in the orders Capnodiales, Hysteriales, Jahnulales, Mytilinidiales, Patellariales and Pleosporales. Most of the fungi sequenced were intertidal mangrove taxa and belong to members of 12 families in the Pleosporales: Aigialaceae, Didymellaceae, Leptosphaeriaceae, Lenthitheciaceae, Lophiostomataceae, Massarinaceae, Montagnulaceae, Morosphaeriaceae, Phaeosphaeriaceae, Pleosporaceae, Testudinaceae and Trematosphaeriaceae. Two new families are described: Aigialaceae and Morosphaeriaceae, and three new genera proposed: Halomassarina, Morosphaeria and Rimora.
    [Show full text]
  • Phylogeny and Taxonomy of the Genus Cylindrocladiella
    Mycol Progress DOI 10.1007/s11557-011-0799-1 ORIGINAL ARTICLE Phylogeny and taxonomy of the genus Cylindrocladiella L. Lombard & R. G. Shivas & C. To-Anun & P. W. Crous Received: 10 June 2011 /Revised: 10 November 2011 /Accepted: 25 November 2011 # The Author(s) 2012. This article is published with open access at Springerlink.com Abstract The genus Cylindrocladiella was established to the 18 new Cylindrocladiella species described in this study accommodate Cylindrocladium-like fungi that have small, based on morphological and sequence data, several species cylindrical conidia and aseptate stipe extensions. Contemporary complexes remain unresolved. taxonomic studies of these fungi have relied on morphology and to a lesser extent on DNA sequence comparisons of the internal Keywords Cylindrocladiella . Cryptic species . Phylogeny. transcribed spacer regions (ITS 1, 2 and 5.8S gene) of the Taxonomy ribosomal RNA and the β-tubulin gene regions. In the present study, the identity of several Cylindrocladiella isolates collected over two decades was determined using morphology and phy- Introduction logenetic inference. A phylogeny constructed for these isolates employing the β-tubulin, histone H3, ITS, 28S large subunit and The genus Cylindrocladiella was established by Boesewinkel translation elongation factor 1-alpha gene regions resulted in the (1982) to accommodate five Cylindrocladium-like species identification of several cryptic species in the genus. In spite of producing small, cylindrical conidia. Cylindrocladiella, which is based on
    [Show full text]
  • Mass Flow in Hyphae of the Oomycete Achlya Bisexualis
    Mass flow in hyphae of the oomycete Achlya bisexualis A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Science in Cellular and Molecular Biology in the University of Canterbury by Mona Bidanjiri University of Canterbury 2018 Abstract Oomycetes and fungi grow in a polarized manner through the process of tip growth. This is a complex process, involving extension at the apex of the cell and the movement of the cytoplasm forward, as the tip extends. The mechanisms that underlie this growth are not clearly understood, but it is thought that the process is driven by the tip yielding to turgor pressure. Mass flow, the process where bulk flow of material occurs down a pressure gradient, may play a role in tip growth moving the cytoplasm forward. This has previously been demonstrated in mycelia of the oomycete Achlya bisexualis and in single hypha of the fungus Neurospora crassa. Microinjected silicone oil droplets were observed to move in the predicted direction after the establishment of an imposed pressure gradient. In order to test for mass flow in a single hypha of A. bisexualis the work in this thesis describes the microinjection of silicone oil droplets into hyphae. Pressure gradients were imposed by the addition of hyperosmotic and hypoosmotic solutions to the hyphae. In majority of experiments, after both hypo- and hyperosmotic treatments, the oil droplets moved down the imposed gradient in the predicted direction. This supports the existence of mass flow in single hypha of A. bisexualis. The Hagen-Poiseuille equation was used to calculate the theoretical rate of mass flow occurring within the hypha and this was compared to observed rates.
    [Show full text]