DOCSLIB.ORG

Ingestion of Cryptophyte Cells by the Marine Photosynthetic Ciliate Mesodinium Rubrum

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Ingestion of Cryptophyte Cells by the Marine Photosynthetic Ciliate Mesodinium Rubrum AQUATIC MICROBIAL ECOLOGY Vol. 36: 165–170, 2004 Published July 21 Aquat Microb Ecol Ingestion of cryptophyte cells by the marine photosynthetic ciliate Mesodinium rubrum Wonho Yih1,*, Hyung Seop Kim1, Hae Jin Jeong2, Geumog Myung1, Young Geel Kim1 1Department of Oceanography, Kunsan National University, San 68, Miryong-dong, Kunsan 573-701, RO Korea 2School of Earth and Environmental Science, College of Natural Sciences, Seoul National University, Seoul 151-747, RO Korea ABSTRACT: We investigated the mechanism of capturing and ingesting cryptophyte cells by a labo- ratory strain of the marine photosynthetic ciliate Mesodinium rubrum Lohmann 1908 (= Myrionecta rubra Jankowski 1976), a cosmopolitan red tide species. When offered cryptophytes as food, M. rubrum, originally grown photosynthetically for 2 wk, used its bifurcated oral tentacles to instantly seize prey cells when encountered. Immediately after capturing a prey cell, M. rubrum swam in a zigzag pattern (30 to 60 µm long linear paths) for >4 s, without showing the large jumps (with ca. 2000 µm long linear paths) that were usually observed when the predator was not feeding. M. rubrum with a cryptophyte attached to its tentacles became motionless while the prey cell was moved to the oral surface of the predator, a process that took <10 s. Engulfment of a captured prey cell by M. rubrum occurred through a cytostome-like structure and took ca. 15 s. Once engulfed, the prey was slowly delivered to the posterior end of the ciliate over a period of ca. 63 s. The whole feeding process lasted approximately 92 s. With increasing mean prey concentration, specific growth rates of M. rubrum feeding on the cryptophyte increased, with saturation at a mean prey concentration of 44 cells ml–1. The maximum specific growth rate (mixotrophic growth) of M. rubrum feeding on the cryptophyte was 0.521 d–1, under continuous illumination of 60 µE m–2 s–1, while its growth rate (phototrophic growth) under the same light conditions without added prey was 0.357 d–1. The inges- tion rate of M. rubrum feeding on cryptophytes increased continuously with increasing prey concen- tration. The maximum ingestion rate was 8.9 cryptophytes ciliate–l d–1. M. rubrum may sometimes exert considerable impact on prey populations. KEY WORDS: Feeding · Growth rate · Grazing · Life cycle · Phagotrophy · Red tide Resale or republication not permitted without written consent of the publisher INTRODUCTION M. rubrum was first suggested by Hargraves (1991) based on photographic evidence, and the inclusion of Mesodinium rubrum Lohmann 1908 (= Myrionecta cryptophyte cells in the protoplasm of M. rubrum was rubra Jankowski 1976) (Lynn & Small 2002) is a plank- later documented by Gustafson et al. (2000) using data tonic ciliate that sometimes forms red tides (Powers from cytological, epifluorescence microscopy and flow 1932, Taylor et al. 1971, Lindholm 1985). The nutri- cytometry. The pre-capture behavior and feeding pro- tional mode of M. rubrum has been under debate for a cess of M. rubrum on cryptophytes, however, have not long time, and it is listed as an obligate phototroph yet been documented. (Sieburth et al. 1978) and/or a species with the poten- To investigate the feeding process of Mesodinium tial for heterotrophy (Smith & Barber 1979). The inclu- rubrum grazing on cryptophytes, we established a sion of functional cryptophyte plastids (Barber et culture of M. rubrum from coastal waters of Korea and al. 1969, Hibberd 1977) as ‘incomplete symbionts’ followed the capture and ingestion of prey using a (Oakley & Taylor 1978) has also led to the speculation video system. We also measured ingestion rates of M. that M. rubrum is a potential mixotrophic ciliate (Lind- rubrum feeding on cryptophytes as a function of prey holm & Mörk 1989). Ingestion of cryptophyte cells by concentration. *Email: [email protected] © Inter-Research 2004 · www.int-res.com 166 Aquat Microb Ecol 36: 165–170, 2004 The results of the present study provide a basis for Feeding processes. To record the feeding process of understanding the feeding mechanism of Mesodinium Mesodinium rubrum on cryptophytes, actively swim- rubrum grazing on cryptophytes and the impact of ming M. rubrum cells that had been starved (i.e. grown such grazing on prey populations. photosynthetically) for 2 wk were added to 6-well tissue culture plates containing prey. Images of feed- ing M. rubrum were taken continuously over the fol- MATERIALS AND METHODS lowing 10 h using a Nikon camera and a video camera system (Watec 202B video camera) mounted on an Clonal culture of a cryptophyte. The clonal culture Olympus compound microscope at magnifications of of an unidentified cryptophyte (CR-MAL01) was estab- 400× (for the Nikon camera) and 200× (for the video lished by isolating single cells from water samples col- camera). lected at Gomso Bay, Korea (35° 40’ N, 126° 40’ E) in Ingestion and growth rates. This experiment was February 2002. The cryptophyte culture was grown designed to measure growth and ingestion rates of at 15°C in enriched f/2 seawater media (Guillard & Mesodinium rubrum, as a function of the prey concen- Ryther 1962) minus silicate under continuous illumina- tration, when feeding on cryptophytes of 5 different tion of 25 µE m–2 s–1 provided by cool-white fluorescent concentrations (0, 75, 1500, 7500, 15 000 cells ml–1). lamps. For feeding experiments, we used cultures in Photosynthetically grown, 2 wk old cultures of M. exponential growth phase. rubrum were diluted with f/2 media in 500 ml PC bot- Isolation and culturing of Mesodinium rubrum. tles to obtain experimental cultures at 1500 cells ml–1. Individual M. rubrum cells were isolated from natural The abundances of M. rubrum and prey were deter- assemblages of Gomso Bay during May 2001, when mined by enumerating cells in three 1 ml Sedgwick- water temperature and salinity were approximately Rafter counting chambers (SRCs). 18°C and 31.5 psu, respectively. Each of the isolated M. Initial concentrations of cryptophytes were estab- rubrum cells was washed by serially transferring into 3 lished using an autopipette by delivering predeter- droplets of f/2 medium and then put into 2 ml of f/2 mined volumes of cryptophyte culture (CR-MAL01) to medium with 5 prey cells held in a 3 ml well of a the bottles. Duplicate 500 ml PC experimental bottles 24-well tissue culture plate. The culture plates were (mixtures of predator and prey) and duplicate control incubated at 15°C under continuous illumination of bottles (prey only) were set up at each predator-prey 60 µE m–2 s–1 provided by cool white fluorescent light. combination. Duplicate control bottles containing only Every 5 to 6 d, cryptophyte prey (CR-MAL01) were Mesodinium rubrum were also established at 1 preda- added to each 3 ml well containing M. rubrum, with tor concentration. All the experimental bottles were the density of cryptophytes adjusted to be 5 times that kept under continuous illumination of 60 µE m–2 s–1 of of the M. rubrum cells. Once dense cultures of M. cool white fluorescent and culture-room temperature rubrum were obtained, they were transferred to 500 ml of 15°C. To determine predator and prey densities at polycarbonate (PC) bottles containing f/2 medium. the same time of day (i.e. 16:00 h) from the beginning Subsequent transfers were made at intervals of 5 to 6 d to the end of the 10 d long experiment, a 5 ml aliquot by placing one-third of a culture in a 500 ml PC bottle was removed from each bottle and fixed with 5% into a new PC bottle containing f/2 medium and cryp- Lugol’s solution, and all or >200 M. rubrum and prey tophytes adjusted to be 5 times that of the M. rubrum cells in three 1 ml SRCs were enumerated. cells. Experiments were conducted when a large The specific growth rate of Mesodinium rubrum (µ,d–1) volume of M. rubrum culture (MR-MAL01) became was calculated by averaging the instantaneous growth available. rates (IGR) for each sampling interval, calculated as: Cell dimension and volume. Mean size, surface area ln(SS͞ ) and volume of the prey cryptophyte and Mesodinium IGR = tt21× 24 (1) tt− rubrum cells (Table 1) were obtained with an elec- 21 tronic particle counter (Coulter Multisizer II, Coulter where t2 – t1 = 24 h and St1 and St2 = the concentration Corporation). of M. rubrum at consecutive samplings. The final t2 for Table 1. Prey cryptophyte species and ciliate Mesodinium rubrum used in the present study. Mean and standard error (SE) of equivalent spherical diameter (ESD) and cell volume were measured by the Coulter Multisizer II electronic particle counter Species Strain no. ESD (µm) Cell volume (µm3) Sampling area (and date) Unidentified cryptophyte CR-MAL01 5.3 ± 0.0047 76.1 ± 0.22 Gomso Bay (Feb 8, 2002) Mesodinium rubrum MR-MAL01 22.0 ± 0.040 5996 ± 30.0 Gomso Bay (May 31, 2001) Yih et al.: Ingestion of cryptophyte cells by Mesodinium rubrum 167 calculation was 72 h, which provided the highest specific growth rate. AB Data for Mesodinium rubrum growth rate (GR) were fitted to a Michaelis-Menten equation: µ (’)xx− µ = max (2) Kxx+−(’) GR –1 where µmax = the maximum GR (d ); x = prey concen- tration (cells ml–1); x’ = threshold prey concentration (the prey concentration where µ = 0); and KGR = the 1 µ CD prey concentration sustaining ⁄2 max. Data were itera- tively fitted to the model using DeltaGraph® (Delta Point). Ingestion rate (IR) was calculated using the equa- tions of Frost (1972) and Heinbokel (1978). Incubation time for calculating ingestion rate was the same as for estimating growth rate. Ingestion rate data were fitted to a Michaelis-Menten equation: EF Ix() IR = max (3) Kx+ () IR –1 –1 where Imax = the maximum IR (cells Mesodinium d ); –1 x = prey concentration (cells ml ), and KIR = the prey 1 concentration sustaining ⁄2 Imax.
Load more

Recommended publications
  • Cryptophyte Farming by Symbiotic Ciliate Host Detected in Situ
    Cryptophyte farming by symbiotic ciliate host detected in situ Dajun Qiua, Liangmin Huanga, and Senjie Linb,1 aChinese Academy of Sciences Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; and bDepartment of Marine Sciences, University of Connecticut, Groton, CT 06340 Edited by David M. Karl, University of Hawaii, Honolulu, HI, and approved September 8, 2016 (received for review July 28, 2016) Protist–alga symbiosis is widespread in the ocean, but its character- as the causative species of the bloom, with no detectable crypto- istics and function in situ remain largely unexplored. Here we report phytes and hardly any other organisms present in the bloom water − the symbiosis of the ciliate Mesodinium rubrum with cryptophyte (Fig. 1B). At 1.03 × 106 cells L 1, M. rubrum abundance in the bloom cells during a red-tide bloom in Long Island Sound. In contrast to was over 100-fold higher than the annual peak in Long Island Sound the current notion that Mesodinium retains cryptophyte chloroplasts (15). Each Mesodinium cell harbored 20 to 30 cryptophyte cells (n = or organelles, our multiapproach analyses reveal that in this bloom 16), which packed the peripheral region of the M. rubrum cells (Fig. the endosymbiotic Teleaulax amphioxeia cells were intact and 1E), with complete cell structures, including cell membranes, nuclei, expressing genes of membrane transporters, nucleus-to-cytoplasm and chloroplasts (Fig. 1C). Taking advantage of the large cell size of RNA transporters, and all major metabolic pathways. Among the Mesodinium spp. (width, 20 to 23 μm; length, 25 to 26 μm), we most highly expressed were ammonium transporters in both organ- picked M.
    [Show full text]
  • Mixotrophic Protists Among Marine Ciliates and Dinoflagellates: Distribution, Physiology and Ecology
    FACULTY OF SCIENCE UNIVERSITY OF COPENHAGEN PhD thesis Woraporn Tarangkoon Mixotrophic Protists among Marine Ciliates and Dinoflagellates: Distribution, Physiology and Ecology Academic advisor: Associate Professor Per Juel Hansen Submitted: 29/04/10 Contents List of publications 3 Preface 4 Summary 6 Sammenfating (Danish summary) 8 สรุป (Thai summary) 10 The sections and objectives of the thesis 12 Introduction 14 1) Mixotrophy among marine planktonic protists 14 1.1) The role of light, food concentration and nutrients for 17 the growth of marine mixotrophic planktonic protists 1.2) Importance of marine mixotrophic protists in the 20 planktonic food web 2) Marine symbiont-bearing dinoflagellates 24 2.1) Occurrence of symbionts in the order Dinophysiales 24 2.2) The spatial distribution of symbiont-bearing dinoflagellates in 27 marine waters 2.3) The role of symbionts and phagotrophy in dinoflagellates with symbionts 28 3) Symbiosis and mixotrophy in the marine ciliate genus Mesodinium 30 3.1) Occurrence of symbiosis in Mesodinium spp. 30 3.2) The distribution of marine Mesodinium spp. 30 3.3) The role of symbionts and phagotrophy in marine Mesodinium rubrum 33 and Mesodinium pulex Conclusion and future perspectives 36 References 38 Paper I Paper II Paper III Appendix-Paper IV Appendix-I Lists of publications The thesis consists of the following papers, referred to in the synthesis by their roman numerals. Co-author statements are attached to the thesis (Appendix-I). Paper I Tarangkoon W, Hansen G Hansen PJ (2010) Spatial distribution of symbiont-bearing dinoflagellates in the Indian Ocean in relation to oceanographic regimes. Aquat Microb Ecol 58:197-213.
    [Show full text]
  • Pigment Composition in Four Dinophysis Species (Dinophyceae
    Running head: Dinophysis pigment composition 1 Pigment composition in three Dinophysis species (Dinophyceae) 2 and the associated cultures of Mesodinium rubrum and Teleaulax amphioxeia 3 4 Pilar Rial 1, José Luis Garrido 2, David Jaén 3, Francisco Rodríguez 1* 5 1Instituto Español de Oceanografía. Subida a Radio Faro, 50. 36200 Vigo, Spain. 6 2Instituto de Investigaciones Marinas, Consejo Superior de Investigaciones Científicas 7 C/ Eduardo Cabello 6. 36208 Vigo, Spain. 8 3Laboratorio de Control de Calidad de los Recursos Pesqueros, Agapa, Consejería de Agricultura, Pesca y Medio 9 Ambiente, Junta de Andalucía, Ctra Punta Umbría-Cartaya Km. 12 21459 Huelva, Spain. 10 *CORRESPONDING AUTHOR: [email protected] 11 12 Despite the discussion around the nature of plastids in Dinophysis, a comparison of pigment 13 signatures in the three-culture system (Dinophysis, the ciliate Mesodinium rubrum and the 14 cryptophyte Teleaulax amphioxeia) has never been reported. We observed similar pigment 15 composition, but quantitative differences, in four Dinophysis species (D. acuminata, D. acuta, D. 16 caudata and D. tripos), Mesodinium and Teleaulax. Dinophysis contained 59-221 fold higher chl a 17 per cell than T. amphioxeia (depending on the light conditions and species). To explain this result, 18 several reasons (e.g. more chloroplasts than previously appreciated and synthesis of new pigments) 19 were are suggested. 20 KEYWORDS: Dinophysis, Mesodinium, Teleaulax, pigments, HPLC. 21 22 INTRODUCTION 23 Photosynthetic Dinophysis species contain plastids of cryptophycean origin (Schnepf and 24 Elbrächter, 1999), but there continues a major controversy around their nature, whether there exist 25 are only kleptoplastids or any permanent ones (García-Cuetos et al., 2010; Park et al., 2010; Kim et 26 al., 2012a).
    [Show full text]
  • Associations Between Mesodinium Rubrum and Cryptophyte Algae in the Columbia River Estuary
    Vol. 68: 117–130, 2013 AQUATIC MICROBIAL ECOLOGY Published online January 29 doi: 10.3354/ame01598 Aquat Microb Ecol Associations between Mesodinium rubrum and cryptophyte algae in the Columbia River estuary Tawnya D. Peterson1,2,*, Rachel L. Golda1,2, Michael L. Garcia1,2, Binglin Li1,2, Michelle A. Maier1,2, Joseph A. Needoba1,2, Peter Zuber1,2 1Institute of Environmental Health, Division of Environmental and Biomolecular Systems, Oregon Health & Science University, 20000 NW Walker Rd., Beaverton, Oregon 97006, USA 2Science and Technology Center for Coastal Margin Observation and Prediction, 20000 NW Walker Rd., Beaverton, Oregon 97006, USA ABSTRACT: Recurring blooms of the photosynthetic ciliate Mesodinium rubrum (= Myrionecta rubra) are observed each summer in the Columbia River estuary. Although cultured isolates of M. rubrum have been shown to consume cryptophyte prey during growth, the feeding behavior of M. rubrum in the field is poorly known. In the present study, a 3 mo time series of observations from a locale of putative bloom formation (Ilwaco harbor in Baker Bay, WA) showed that crypto- phytes were present at relatively high abundance prior to and during M. rubrum blooms and declined with M. rubrum abundance. During 3 years of observation (summers of 2009, 2010, and 2011), we observed M. rubrum cells bearing numerous cryptophytes attached to the cirri through- out the estuary, especially during the bloom initiation phase and particularly in the peripheral bays. We performed a laboratory investigation in 2011 in which cryptophyte prey were introduced to high-density red-water samples in aquarium tanks. Within 2 h, individual M. rubrum cells collected multiple cryptophytes on their cirri, likely as a precursor to ingestion.
    [Show full text]
  • Sequestration, Performance, and Functional Control of Cryptophyte Plastids in the Ciliate Myrionecta Rubra (Ciliophora)1
    J. Phycol. 42, 1235–1246 (2006) r 2006 by the Phycological Society of America DOI: 10.1111/j.1529-8817.2006.00275.x SEQUESTRATION, PERFORMANCE, AND FUNCTIONAL CONTROL OF CRYPTOPHYTE PLASTIDS IN THE CILIATE MYRIONECTA RUBRA (CILIOPHORA)1 Matthew D. Johnson2 Horn Point Laboratory, Center for Environmental Science, University of Maryland, Cambridge, Maryland 21613, USA Torstein Tengs National Veterinary Institute, Section of Food and Feed Microbiology, Ullevaalsveien 68, 0454 Oslo, Norway David Oldach Institute of Human Virology, School of Medicine, University of Maryland, Baltimore, Maryland, USA and Diane K. Stoecker Horn Point Laboratory, Center for Environmental Science, University of Maryland, Cambridge, Maryland 21613, USA Myrionecta rubra (Lohmann 1908, Jankowski Key index words: ciliate; Geminigera cryophila; 1976) is a photosynthetic ciliate with a global dis- mixotrophy; Myrionecta rubra; nucleomorph; or- tribution in neritic and estuarine habitats and has ganelle sequestration long been recognized to possess organelles of Abbreviations: CMC, chloroplast–mitochondria cryptophycean origin. Here we show, using nucleo- complex; HL, high light; LL, low light; LMWC, morph (Nm) small subunit rRNA gene sequence low-molecular-weight compound; MAA, micros- data, quantitative PCR, and pigment absorption scans, that an M. rubra culture has plastids identi- porine-like amino acids; ML, maximum likelihood; NGC, number of genomes per cell; PE, photosyn- cal to those of its cryptophyte prey, Geminigera thesis versus irradiance; TBR, tree bisection-recon- cf. cryophila (Taylor and Lee 1971, Hill 1991). Using quantitative PCR, we demonstrate that G. cf. struction cryophila plastids undergo division in growing M. rubra and are regulated by the ciliate. M. rubra maintained chl per cell and maximum cellu- Myrionecta rubra (5Mesodinium rubrum) (Lohmann cell lar photosynthetic rates (Pmax) that were 6–8 times 1908, Jankowski 1976) (Mesodiniidae, Litostomatea) that of G.
    [Show full text]
  • Mass Entrapment and Lysis of Mesodinium Rubrum Cells in Mucus
    Harmful Algae 55 (2016) 77–84 Contents lists available at ScienceDirect Harmful Algae jo urnal homepage: www.elsevier.com/locate/hal Mass entrapment and lysis of Mesodinium rubrum cells in mucus threads observed in cultures with Dinophysis a, b a K. Ojama¨e *, P.J. Hansen , I. Lips a Marine Systems Institute, Tallinn University of Technology, Akadeemia rd. 15a, 12618 Tallinn, Estonia b Marine Biological Section, University of Copenhagen, Strandpromenaden 5, DK-3000 Helsingør, Denmark A R T I C L E I N F O A B S T R A C T Article history: The entrapment and death of the ciliate Mesodinium rubrum in the mucus threads in cultures with Received 3 March 2015 Dinophysis is described and quantified. Feeding experiments with different concentrations and Received in revised form 9 October 2015 predator–prey ratios of Dinophysis acuta, Dinophysis acuminata and M. rubrum to study the motility loss Accepted 15 January 2016 and aggregate formation of the ciliates and the feeding behaviour of Dinophysis were carried out. In Available online 2 March 2016 cultures of either Dinophysis species, the ciliates became entrapped in the mucus, which led to the formation of immobile aggregates of M. rubrum and subsequent cell lysis. The proportion of entrapped Keywords: ciliates was influenced by the concentration of Dinophysis and the ratio of predator and prey in the Cell lysis À1 À1 cultures. At high cell concentrations of prey (136 cells mL ) and predator (100 cells mL ), a maximum Dinophysis of 17% of M. rubrum cells became immobile and went through cell lysis. Ciliates were observed trapped in Mesodinium rubrum Mixotrophy the mucus even when a single D.
    [Show full text]
  • Mesodinium Rubrum Erica Lasek-Nesselquist1*, Jennifer H
    Lasek-Nesselquist et al. BMC Genomics (2015) 16:805 DOI 10.1186/s12864-015-2052-9 RESEARCH ARTICLE Open Access Insights into transcriptional changes that accompany organelle sequestration from the stolen nucleus of Mesodinium rubrum Erica Lasek-Nesselquist1*, Jennifer H. Wisecaver2, Jeremiah D. Hackett3 and Matthew D. Johnson4* Abstract Background: Organelle retention is a form of mixotrophy that allows organisms to reap metabolic benefits similar to those of photoautotrophs through capture of algal prey and sequestration of their plastids. Mesodinium rubrum is an abundant and broadly distributed photosynthetic marine ciliate that steals organelles from cryptophyte algae, such as Geminigera cryophila. M. rubrum is unique from most other acquired phototrophs because it also steals a functional nucleus that facilitates genetic control of sequestered plastids and other organelles. We analyzed changes in G. cryophila nuclear gene expression and transcript abundance after its incorporation into the cellular architecture of M. rubrum as an initial step towards understanding this complex system. Methods: We compared Illumina-generated transcriptomes of the cryptophyte Geminigera cryophila as a free-living cell and as a sequestered nucleus in M. rubrum to identify changes in protein abundance and gene expression. After KEGG annotation, proteins were clustered by functional categories, which were evaluated for over- or under-representation in the sequestered nucleus. Similarly, coding sequences were grouped by KEGG categories/ pathways, which were then evaluated for over- or under-expression via read count strategies. Results: At the time of sampling, the global transcriptome of M. rubrum was dominated (~58–62 %) by transcription from its stolen nucleus. A comparison of transcriptomes from free-living G.
    [Show full text]
  • Effect of Mesodinium Rubrum (= Myrionecta Rubra) on the Action and Absorption Spectra of Phytoplankton in a Coastal Marine Inlet
    06kyewalyanga 82W(ds) 2/7/02 8:50 am Page 687 JOURNAL OF PLANKTON RESEARCH VOLUME NUMBER PAGES ‒ Effect of Mesodinium rubrum (= Myrionecta rubra) on the action and absorption spectra of phytoplankton in a coastal marine inlet MARGARETH KYEWALYANGA*, SHUBHA SATHYENDRANATH1,2 AND TREVOR PLATT2 INSTITUTE OF MARINE SCIENCES, UNIVERSITY OF DAR ES SALAAM, PO BOX , ZANZIBAR, TANZANIA, 1DEPARTMENT OF OCEANOGRAPHY, DALHOUSIE UNIVERSITY, HALIFAX, NOVA SCOTIA BH J AND 2BIOLOGICAL OCEANOGRAPHY DIVISION, BEDFORD INSTITUTE OF OCEANOGRAPHY, BOX , DARTMOUTH, NOVA SCOTIA BY A, CANADA *CORRESPONDING AUTHOR: EMAIL: [email protected] This study, carried out at a single station in the Bedford Basin (Nova Scotia, Canada), examined time-dependent changes in the physical and chemical conditions of the waters with associated changes in species composition and some photosynthesis properties of phytoplankton. The sampling period covered late summer months (August and September) and fall months (October to December). Changes in the water conditions were found to influence species composition, which in turn had an effect on the shapes and amplitudes of the action and absorption spectra of phytoplankton, and on the maximum quantum yield of photosynthesis. The most remarkable change was observed in October during a bloom of Mesodinium rubrum, a ciliate harbouring photosynthetic endosymbionts rich in phycobilins. The presence of M. rubrum yielded atypical shapes of the measured photosynthetic action spectra; furthermore, other photosynthesis properties changed significantly. These results demonstrate that the presence of certain pigments in the water column may be associated with a marked shift from what may be considered typical (representative) photosynthesis properties of phytoplankton. INTRODUCTION Shapes of action and absorption spectra have been shown to vary both spatially and temporally.
    [Show full text]
  • (Non-Toxic Red Tide) in Malacca River, Malaysia
    Jurnal Biologi Indonesia 13(1): 171-173 (2017) SHORT COMMUNICATION Notes on the Mass Occurrence of the Ciliate Mesodinium rubrum (non-toxic red tide) in Malacca River, Malaysia Suriyanti Su Nyun Pau*1, Dzulhelmi Muhammad Nasir2 & Gires Usup1 1 School of Environmental Science and Natural Resources, Faculty Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia 2Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia *E-mail: [email protected] Received: January 2016, Accepted: March 2016 Malacca is a famous tourist spot in Malaysia tourism activity. which have been listed as the World Heritage Plankton sample was collected from the site by the UNESCO in 2008 (UNESCO). The Malacca River (N2° 12’ 14.80” E102° 12’ 05.17”) Malacca Tourism Board conducts cruising and water surface (less than 10 meters) during the sight seeing activities along the Malacca River. fish kill event using 20 mm plankton net. The Hundreds of wild marine and freshwater fishes salinity was determined using hand refractometer (catfish, pomfret, mullet and scat) were reported (Atago, Japan). Samples were preserved with floating and dead in Malacca River, Malaysia Lugol’s solution and observed directly under on 22 April 2014 (Berita Harian 2014). 50× dissecting microscope (Nikon SMZ645, Environmental Board of Malacca authority had Japan). The morphology of M. rubrum was further analyzed the water quality and no harmful examined using epifluorescence microscope chemicals were detected that may have caused (Olympus U-LH100-3, Japan). Cell micrographs the fish kill (Berita Harian 2014). Nonetheless, were captured using built in camera (Olympus U the authority claimed that the amount of -TV1x, Japan) and measured with analysis LS dissolved oxygen was significantly low (Berita Professional software by Olympus.
    [Show full text]
  • Role of Dissolved Nitrate and Phosphate in Isolates of Mesodinium Rubrum and Toxin-Producing Dinophysis Acuminata
    W&M ScholarWorks VIMS Articles Virginia Institute of Marine Science 2015 Role of dissolved nitrate and phosphate in isolates of Mesodinium rubrum and toxin-producing Dinophysis acuminata MM Tong JL Smith Virginia Institute of Marine Science DM Kulis DM Anderson Follow this and additional works at: https://scholarworks.wm.edu/vimsarticles Part of the Aquaculture and Fisheries Commons Recommended Citation Tong, MM; Smith, JL; Kulis, DM; and Anderson, DM, "Role of dissolved nitrate and phosphate in isolates of Mesodinium rubrum and toxin-producing Dinophysis acuminata" (2015). VIMS Articles. 854. https://scholarworks.wm.edu/vimsarticles/854 This Article is brought to you for free and open access by the Virginia Institute of Marine Science at W&M ScholarWorks. It has been accepted for inclusion in VIMS Articles by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. HHS Public Access Author manuscript Author ManuscriptAuthor Manuscript Author Aquat Microb Manuscript Author Ecol. Author Manuscript Author manuscript; available in PMC 2016 October 07. Published in final edited form as: Aquat Microb Ecol. 2015 ; 75(2): 169–185. doi:10.3354/ame01757. Role of dissolved nitrate and phosphate in isolates of Mesodinium rubrum and toxin-producing Dinophysis acuminata Mengmeng Tong1,2, Juliette L. Smith2,3, David M. Kulis2, and Donald M. Anderson2 1Ocean College, Zhejiang University, Hangzhou, 310058, China 2Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA 3Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, VA, 23062, USA Abstract Dinophysis acuminata, a producer of toxins associated with diarrhetic shellfish poisoning (DSP) and/or pectenotoxins (PTXs), is a mixotrophic species that requires both ciliate prey and light for growth.
    [Show full text]
  • Photosynthesis in Mesodinium Rubrum: Species- Specific Measurements and Comparison to Community Rates
    MARINE ECOLOGY PROGRESS SERIES Vol. 73: 245-252, 1991 Published July 11 Mar. Ecol. Prog. Ser. Photosynthesis in Mesodinium rubrum: species- specific measurements and comparison to community rates Diane K. ~toecker'~*,Mary putt2,Linda H. ~avis',Ann E. ~ichaels' ' Biology Department. Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA Oceanography Department. Old Dominion University. Norfolk, Virginia 23529-0276. USA ABSTRACT. The photosynthetic chate Mesodinium rubrum is a common component of the plankton in estuarine, coastal and offshore areas. Unusually high photosynthetic rates [210 pg C (pg chl a)-' h-'] have been measured during vlsible blooms (red-waters) of this species, but llttle data were available on photosynthesis by Mesodmium during more routine conditions. We used single cell techniques to measure chlorophyll content and rates of photosynthesis in Mesodinium (16 to 18 X 21 to 22 pm in size) that were part of mixed-species phytoplankton assemblages in small estuaries and salt ponds. The carbon:chlorophyll a (wt:wt) ratio for Mesodinium ranged from 47 to 78. Light-saturated rates of photosynthesis ranged from 13 to 88 pg C cell-' h-' 11.8 to 8.6 pg C (pg chl a)-' h-']. These species- specific assimilation ratios were within the mid-range reported for community measurements made during Mesodinium red-waters and within the range reported for phytoplankton. Ik values for Mesodiniurn were 2- 275 pE m-' S-' in all experiments. At saturating irradiance, carbon fixation ranged up to ca 14 % of body C h-' In our incubations, Mesodinium accounted for from < 1 to 2-70 % of the community primary production in surface water samples although at no time during our studies did it cause red-waters.
    [Show full text]
  • Plastid Retention, Use, and Replacement in a Kleptoplastidic Ciliate
    Vol. 67: 177–187, 2012 AQUATIC MICROBIAL ECOLOGY Published online November 2 doi: 10.3354/ame01601 Aquat Microb Ecol OPENPEN ACCESSCCESS FEATURE ARTICLE Plastid retention, use, and replacement in a kleptoplastidic ciliate D. M. Schoener*, G. B. McManus Department of Marine Sciences, University of Connecticut, Groton, Connecticut 06340, USA ABSTRACT: The marine oligotrich ciliate Strombid- ium rassoulzadegani retains and utilizes the chloro- plasts of its algal food. It does not appear to be able to induce its captured plastids to divide, and so the plas- tids must be replaced with new ones from recently ingested food. We measured the plastid replacement rate of S. rassoulzadegani, its growth and feeding rates, chlorophyll retention, and mortality when starved, and determined whether the ciliate showed differential grazing or plastid retention when pre- sented with different algal foods. S. rassoulzadegani had similar mortality rates when starved following growth on either Tetraselmis chui or Rhodomonas lens. When presented with a source for new plastids, the ciliate can incorporate its first new plastid within 30 min and completely replace all of its plastids within 48 to 72 h. S. rassoulzadegani did not show a Strombidium rassoulzadegani fed Tetraselmis chui (top left), Rhodomonas lens for 15 h (top right), R. lens for 72 h (bottom preference for either Tetraselmis or Rhodomonas left), and after 96 h of starvation (bottom right); fluorescence when grazing. However, it did preferentially acquire image of single squashed cell. the Tetraselmis-derived plastids. Our results contrast Photos: Donald M. Schoener with those for other mixotrophic ciliates; for example, Mesodinium rubrum can maintain its plastids for extended periods of time (weeks), while Strombid- INTRODUCTION ium capitatum can quickly lose (40 h) and replace (9 h) its prey-derived plastids.
    [Show full text]