Feeding Currents Facilitate a Mixotrophic Way of Life
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Molecular Data and the Evolutionary History of Dinoflagellates by Juan Fernando Saldarriaga Echavarria Diplom, Ruprecht-Karls-Un
Molecular data and the evolutionary history of dinoflagellates by Juan Fernando Saldarriaga Echavarria Diplom, Ruprecht-Karls-Universitat Heidelberg, 1993 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE STUDIES Department of Botany We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA November 2003 © Juan Fernando Saldarriaga Echavarria, 2003 ABSTRACT New sequences of ribosomal and protein genes were combined with available morphological and paleontological data to produce a phylogenetic framework for dinoflagellates. The evolutionary history of some of the major morphological features of the group was then investigated in the light of that framework. Phylogenetic trees of dinoflagellates based on the small subunit ribosomal RNA gene (SSU) are generally poorly resolved but include many well- supported clades, and while combined analyses of SSU and LSU (large subunit ribosomal RNA) improve the support for several nodes, they are still generally unsatisfactory. Protein-gene based trees lack the degree of species representation necessary for meaningful in-group phylogenetic analyses, but do provide important insights to the phylogenetic position of dinoflagellates as a whole and on the identity of their close relatives. Molecular data agree with paleontology in suggesting an early evolutionary radiation of the group, but whereas paleontological data include only taxa with fossilizable cysts, the new data examined here establish that this radiation event included all dinokaryotic lineages, including athecate forms. Plastids were lost and replaced many times in dinoflagellates, a situation entirely unique for this group. Histones could well have been lost earlier in the lineage than previously assumed. -
하구 및 연안생태학 Estuarine and Coastal Ecology
하구 및 연안생태학 Estuarine and coastal ecology 2010 년 11월 2 계절적 변동 • 빛과 영양염분의 조건에 따라 • 봄 가을 대발생 계절적 변동 Sverdrup 에 의한 대발생 모델 • Compensation depth (보상심도) • Critical depth (임계수심) Sverdrup 에 의한 대발생 모델 홍재상외, 해양생물학 Sverdrup 에 의한 대발생 모델 봄 여름 가을 겨울 수심 혼합수심 임계수심 (mixed layer depth) (critical depth) Sverdrup 에 의한 대발생 모델 봄 여름 가을 겨울 수심 혼합수심 임계수심 (mixed layer depth) (critical depth) Diatoms (규조류) • Bacillariophyceae (1 fragment of centrics, 19 fragments of pennates in Devonian marble in Poland Kwiecinska & Sieminska 1974) Diatoms (규조류) • Bacillariophyceae • Temperate and high latitude (everywhere) Motility: present in pennate diatoms with a raphe (and male gametes) Resting cells (spores): heavily silicified, often with spines (Î보충설명) Biotopes: marine and freshwater, plankton, benthos, epiphytic, epizooic (e.g., on whales, crustaceans) endozoic, endophytic, discolouration of arctic and Antarctic sea ice Snow Algae (규조류 아님) Snow algae describes cold-tolerant algae and cyanobacteria that grow on snow and ice during alpine and polar summers. Visible algae blooms may be called red snow or watermelon snow. These extremophilic organisms are studied to understand the glacial ecosystem. Snow algae have been described in the Arctic, on Arctic sea ice, and in Greenland, the Antarctic, Alaska, the west coast, east coast, and continental divide of North America, the Himalayas, Japan, New Guinea, Europe (Alps, Scandinavia and Carpathians), China, Patagonia, Chile, and the South Orkney Islands. Diatoms (규조류) • Bacillariophyceae • Temperate and high latitude (everywhere) • 2~1000 um • siliceous frustules • Various patterns in frustule Centric vs Pennate Centric diatom Pennete small discoid plastid large plate plastid Navicula sp. -
Flagellum Couples Cell Shape to Motility in Trypanosoma Brucei
Flagellum couples cell shape to motility in Trypanosoma brucei Stella Y. Suna,b,c, Jason T. Kaelberd, Muyuan Chene, Xiaoduo Dongf, Yasaman Nematbakhshg, Jian Shih, Matthew Doughertye, Chwee Teck Limf,g, Michael F. Schmidc, Wah Chiua,b,c,1, and Cynthia Y. Hef,h,1 aDepartment of Bioengineering, James H. Clark Center, Stanford University, Stanford, CA 94305; bDepartment of Microbiology and Immunology, James H. Clark Center, Stanford University, Stanford, CA 94305; cSLAC National Accelerator Laboratory, Stanford University, Menlo Park, CA 94025; dDepartment of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030; eVerna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030; fMechanobiology Institute, National University of Singapore, Singapore 117411; gDepartment of Mechanical Engineering, National University of Singapore, Singapore 117575; and hDepartment of Biological Sciences, Center for BioImaging Sciences, National University of Singapore, Singapore 117543 Contributed by Wah Chiu, May 17, 2018 (sent for review December 29, 2017; reviewed by Phillipe Bastin and Abraham J. Koster) In the unicellular parasite Trypanosoma brucei, the causative Cryo-electron tomography (cryo-ET) allows us to view 3D agent of human African sleeping sickness, complex swimming be- supramolecular details of biological samples preserved in their havior is driven by a flagellum laterally attached to the long and proper cellular context without chemical fixative and/or metal slender cell body. Using microfluidic assays, we demonstrated that stain. However, samples thicker than 1 μm are not accessible to T. brucei can penetrate through an orifice smaller than its maxi- cryo-ET because at typical accelerating voltages (≤300 kV), few mum diameter. -
Growth and Grazing Rates of the Herbivorous Dinoflagellate Gymnodinium Sp
MARINE ECOLOGY PROGRESS SERIES Published December 16 Mar. Ecol. Prog. Ser. Growth and grazing rates of the herbivorous dinoflagellate Gymnodinium sp. from the open subarctic Pacific Ocean Suzanne L. Strom' School of Oceanography WB-10, University of Washington. Seattle. Washington 98195, USA ABSTRACT: Growth, grazing and cell volume of the small heterotroph~cdinoflagellate Gyrnnodin~um sp. Isolated from the open subarctic Pacific Ocean were measured as a funct~onof food concentration using 2 phytoplankton food species. Growth and lngestlon rates increased asymptotically with Increas- ing phytoplankon food levels, as did grazer cell volume; rates at representative oceanic food levels were high but below maxima. Clearance rates decreased with lncreaslng food levels when Isochrysis galbana was the food source; they increased ~vithlncreaslng food levels when Synechococcus sp. was the food source. There was apparently a grazlng threshold for Ingestion of Synechococcus: below an initial Synechococcus concentration of 20 pgC 1.' ingestion rates on this alga were very low, while above this initial concentratlon Synechococcus was grazed preferent~ally Gross growth efficiency varied between 0.03 and 0.53 (mean 0.21) and was highest at low food concentrations. Results support the hypothesis that heterotrophic d~noflagellatesmay contribute to controlling population increases of small, rap~dly-grow~ngphytoplankton specles even at low oceanic phytoplankton concentrations. INTRODUCTION as Gymnodinium and Gyrodinium is difficult or impos- sible using older preservation and microscopy tech- Heterotrophic dinoflagellates can be a significant niques; experimental emphasis has been on more component of the microzooplankton in marine waters. easily recognizable and collectable microzooplankton In the oceanic realm, Lessard (1984) and Shapiro et al. -
The Planktonic Protist Interactome: Where Do We Stand After a Century of Research?
bioRxiv preprint doi: https://doi.org/10.1101/587352; this version posted May 2, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. Bjorbækmo et al., 23.03.2019 – preprint copy - BioRxiv The planktonic protist interactome: where do we stand after a century of research? Marit F. Markussen Bjorbækmo1*, Andreas Evenstad1* and Line Lieblein Røsæg1*, Anders K. Krabberød1**, and Ramiro Logares2,1** 1 University of Oslo, Department of Biosciences, Section for Genetics and Evolutionary Biology (Evogene), Blindernv. 31, N- 0316 Oslo, Norway 2 Institut de Ciències del Mar (CSIC), Passeig Marítim de la Barceloneta, 37-49, ES-08003, Barcelona, Catalonia, Spain * The three authors contributed equally ** Corresponding authors: Ramiro Logares: Institute of Marine Sciences (ICM-CSIC), Passeig Marítim de la Barceloneta 37-49, 08003, Barcelona, Catalonia, Spain. Phone: 34-93-2309500; Fax: 34-93-2309555. [email protected] Anders K. Krabberød: University of Oslo, Department of Biosciences, Section for Genetics and Evolutionary Biology (Evogene), Blindernv. 31, N-0316 Oslo, Norway. Phone +47 22845986, Fax: +47 22854726. [email protected] Abstract Microbial interactions are crucial for Earth ecosystem function, yet our knowledge about them is limited and has so far mainly existed as scattered records. Here, we have surveyed the literature involving planktonic protist interactions and gathered the information in a manually curated Protist Interaction DAtabase (PIDA). In total, we have registered ~2,500 ecological interactions from ~500 publications, spanning the last 150 years. -
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. -
Construction and Loss of Bacterial Flagellar Filaments
biomolecules Review Construction and Loss of Bacterial Flagellar Filaments Xiang-Yu Zhuang and Chien-Jung Lo * Department of Physics and Graduate Institute of Biophysics, National Central University, Taoyuan City 32001, Taiwan; [email protected] * Correspondence: [email protected] Received: 31 July 2020; Accepted: 4 November 2020; Published: 9 November 2020 Abstract: The bacterial flagellar filament is an extracellular tubular protein structure that acts as a propeller for bacterial swimming motility. It is connected to the membrane-anchored rotary bacterial flagellar motor through a short hook. The bacterial flagellar filament consists of approximately 20,000 flagellins and can be several micrometers long. In this article, we reviewed the experimental works and models of flagellar filament construction and the recent findings of flagellar filament ejection during the cell cycle. The length-dependent decay of flagellar filament growth data supports the injection-diffusion model. The decay of flagellar growth rate is due to reduced transportation of long-distance diffusion and jamming. However, the filament is not a permeant structure. Several bacterial species actively abandon their flagella under starvation. Flagellum is disassembled when the rod is broken, resulting in an ejection of the filament with a partial rod and hook. The inner membrane component is then diffused on the membrane before further breakdown. These new findings open a new field of bacterial macro-molecule assembly, disassembly, and signal transduction. Keywords: self-assembly; injection-diffusion model; flagellar ejection 1. Introduction Since Antonie van Leeuwenhoek observed animalcules by using his single-lens microscope in the 18th century, we have entered a new era of microbiology. -
Acidotropic Probes and Flow Cytometry: a Powerful Combination for Detecting Phagotrophy in Mixotrophic and Heterotrophic Protists
AQUATIC MICROBIAL ECOLOGY Vol. 44: 85–96, 2006 Published August 16 Aquat Microb Ecol Acidotropic probes and flow cytometry: a powerful combination for detecting phagotrophy in mixotrophic and heterotrophic protists Wanderson F. Carvalho*, Edna Granéli Marine Science Department, University of Kalmar, 391 82 Kalmar, Sweden ABSTRACT: Studies with phagotrophic organisms are hampered by a series of methodological con- straints. To overcome problems related to the detection and enumeration of mixotrophic and hetero- trophic cells containing food vacuoles, we combined flow cytometry and an acidotropic blue probe as an alternative method. Flow cytometry allows the analysis of thousands of cells per minute with high sensitivity to the autofluorescence of different groups of cells and to probe fluorescence. The method was first tested in a grazing experiment where the heterotrophic dinoflagellate Oxyrrhis marina fed on Rhodomonas salina. The maximum ingestion rate of O. marina was 1.7 prey ind.–1 h–1, and the fre- quency of cells with R. salina in the food vacuoles increased from 0 to 2.4 ± 0.5 × 103 cells ml–1 within 6 h. The blue probe stained 100% of O. marina cells that had R. salina in the food vacuoles. The acidotropic blue probe was also effective in staining food vacuoles in the mixotrophic dinoflagellate Dinophysis norvegica. We observed that 75% of the D. norvegica population in the aphotic zone pos- sessed food vacuoles. Overall, in cells without food vacuoles, blue fluorescence was as low as in cells that were kept probe free. Blue fluorescence in O. marina cells with food vacuoles was 6-fold higher than in those without food vacuoles (20 ± 4 and 3 ± 0 relative blue fluorescence cell–1, respectively), while in D. -
Oxyrrhis Marina-Based Models As a Tool to Interpret Protozoan Population Dynamics
JOURNAL OF PLANKTON RESEARCH j VOLUME 33 j NUMBER 4 j PAGES 651–663 j 2011 Oxyrrhis marina-based models as a tool to interpret protozoan population dynamics KEITH DAVIDSON 1*, FOTOON SAYEGH 2 AND DAVID J. S. MONTAGNES 3 1 2 SCOTTISH ASSOCIATION FOR MARINE SCIENCE, SCOTTISH MARINE INSTITUTE, OBAN, ARGYLL PA37 1QA, UK, PO BOX 100569, JEDDAH 21311, KINGDOM 3 OF SAUDI ARABIA AND SCHOOL OF BIOLOGICAL SCIENCES, UNIVERSITY OF LIVERPOOL, BIOSCIENCES BUILDING, CROWN STREET, LIVERPOOL L69 7ZB, UK Downloaded from https://academic.oup.com/plankt/article/33/4/651/1473431 by guest on 28 September 2021 *CORRESPONDING AUTHOR: [email protected] Received May 18, 2010; accepted in principle June 22, 2010; accepted for publication July 29, 2010 Corresponding editor: John Dolan Oxyrrhis marina-based experiments have frequently been used to underpin the construction and, or, parameterization of protozoan mathematical models. Initially, we examine the suitability and limitations of O. marina for this task. Subsequently, we summarize the range of aut- and synecological modelling studies based on O. marina, examining the questions asked and conclusions drawn from these, along with the range of processes and functions employed within the models. Finally, we discuss future modelling directions based on studies of O. marina. KEYWORDS: dinoflagellate; experimental design; Oxyrrhis marina; models INTRODUCTION Oxyrrhis marina, that can act as a model for others and With improved understanding of the pivotal role that the insights that have been obtained from mathematical protozoa play within microbial food webs (Azam et al., models based on its study. 1983; Pomeroy et al., 2007), an increasing body of exper- The heterotrophic flagellate O. -
Sexual Development in Plasmodium Parasites: Knowing When It’S Time to Commit
REVIEWS VECTOR-BORNE DISEASES Sexual development in Plasmodium parasites: knowing when it’s time to commit Gabrielle A. Josling1 and Manuel Llinás1–4 Abstract | Malaria is a devastating infectious disease that is caused by blood-borne apicomplexan parasites of the genus Plasmodium. These pathogens have a complex lifecycle, which includes development in the anopheline mosquito vector and in the liver and red blood cells of mammalian hosts, a process which takes days to weeks, depending on the Plasmodium species. Productive transmission between the mammalian host and the mosquito requires transitioning between asexual and sexual forms of the parasite. Blood- stage parasites replicate cyclically and are mostly asexual, although a small fraction of these convert into male and female sexual forms (gametocytes) in each reproductive cycle. Despite many years of investigation, the molecular processes that elicit sexual differentiation have remained largely unknown. In this Review, we highlight several important recent discoveries that have identified epigenetic factors and specific transcriptional regulators of gametocyte commitment and development, providing crucial insights into this obligate cellular differentiation process. Trophozoite Malaria affects almost 200 million people worldwide and viewed under the microscope, it resembles a flat disc. 1 A highly metabolically active and causes 584,000 deaths annually ; thus, developing a After the ring stage, the parasite rounds up as it enters the asexual form of the malaria better understanding of the mechanisms that drive the trophozoite stage, in which it is far more metabolically parasite that forms during development of the transmissible form of the malaria active and expresses surface antigens for cytoadhesion. the intra‑erythrocytic developmental cycle following parasite is a matter of urgency. -
Aquatic Microbial Ecology 80:193
This authors' personal copy may not be publicly or systematically copied or distributed, or posted on the Open Web, except with written permission of the copyright holder(s). It may be distributed to interested individuals on request. Vol. 80: 193–207, 2017 AQUATIC MICROBIAL ECOLOGY Published online October 5 https://doi.org/10.3354/ame01849 Aquat Microb Ecol Grazing of the heterotrophic dinoflagellate Noctiluca scintillans on dinoflagellate and raphidophyte prey Beth A. Stauffer1,*, Alyssa G. Gellene2, Diane Rico3, Christine Sur4, David A. Caron2 1Department of Biology, University of Louisiana at Lafayette, Lafayette, LA 70403, USA 2Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA 3School of Oceanography, University of Washington, Seattle, WA 98105, USA 4Graduate Group in Ecology, University of California, Davis, Davis, CA 95616, USA ABSTRACT: Noctiluca scintillans is a bloom-forming heterotrophic dinoflagellate that can ingest (and grow on) a number of phytoplankton prey, including several potentially toxic phytoplankton species. The current study documented (1) a range of N. scintillans growth rates (μ = −0.09 to 0.83 d−1) on several species of harmful dinoflagellates and raphidophytes, including Heterosigma akashiwo and Akashiwo sanguinea, and (2) the first published growth rates on Lingulodinium polyedrum, Chattonella marina, and Alexandrium catenella. N. scintillans attained maximum growth rates (μ = 0.83 d−1) on the raphidophyte H. akashiwo and negative growth rates (i.e. signif- icant mortality) on the dinoflagellates A. catenella (μ = −0.03 d−1) and A. sanguinea (μ = −0.08 d−1) and the raphidophyte C. marina (μ = −0.09 d−1). Toxin production by A. -
The Mitochondrial Genome and Transcriptome of the Basal
View metadata, citation and similar papers at core.ac.uk brought to you by CORE GBEprovided by PubMed Central The Mitochondrial Genome and Transcriptome of the Basal Dinoflagellate Hematodinium sp.: Character Evolution within the Highly Derived Mitochondrial Genomes of Dinoflagellates C. J. Jackson, S. G. Gornik, and R. F. Waller* School of Botany, University of Melbourne, Australia *Corresponding author: E-mail: [email protected]. Accepted: 12 November 2011 Abstract The sister phyla dinoflagellates and apicomplexans inherited a drastically reduced mitochondrial genome (mitochondrial DNA, mtDNA) containing only three protein-coding (cob, cox1, and cox3) genes and two ribosomal RNA (rRNA) genes. In apicomplexans, single copies of these genes are encoded on the smallest known mtDNA chromosome (6 kb). In dinoflagellates, however, the genome has undergone further substantial modifications, including massive genome amplification and recombination resulting in multiple copies of each gene and gene fragments linked in numerous combinations. Furthermore, protein-encoding genes have lost standard stop codons, trans-splicing of messenger RNAs (mRNAs) is required to generate complete cox3 transcripts, and extensive RNA editing recodes most genes. From taxa investigated to date, it is unclear when many of these unusual dinoflagellate mtDNA characters evolved. To address this question, we investigated the mitochondrial genome and transcriptome character states of the deep branching dinoflagellate Hematodinium sp. Genomic data show that like later-branching dinoflagellates Hematodinium sp. also contains an inflated, heavily recombined genome of multicopy genes and gene fragments. Although stop codons are also lacking for cox1 and cob, cox3 still encodes a conventional stop codon. Extensive editing of mRNAs also occurs in Hematodinium sp.