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36 • "PROTIST—2016
associated with a short cytoplasmic outgrowth and the same was shown for all of Luffisphaera spp., studied for that matter. All organells, described for Luffisphaera were found in Belonocystis and shown to have almost identical organization. Both have tubular mitochondrial cristae and vacuoles associated with stacks of rough endoplasmic reticulum cisternae and neither of them was shown to have kinetosomes. B. marina was the first record of marine species for Belonocystis, which again put it closer to Luffisphaera, initially recorded in marine and freshwater habitats. It's possible that the subsequent study of Luffisphaera and extra Belonocystis isolates in future may lead to a fusion of both or to transfer some species from one genus to another. Study was supported with RFBR grants 15-04-18101_a, 15-29-02749-ofi_m.
HIGH ARCTIC BENTHIC FORAMINIFE-RANS DURING THE POLAR NIGHT: DORMANCY OR ACTIVE FEEDING? Knyazeva O., Korsun S.
Dept Invertebrate Zool, Biol Faculty, St-Petersburg
Univ, Russia
Benthic foraminiferans are the vast meiobenthic group of protists widely represented in all marine habitats including the high Arctic. Although some foraminifera species are known to feed on bacteria, the majority of these protists keep to an algal diet, preying on diatoms and dinofllagelates. Some species are also capable of capturing prey chloroplasts and maintaining them functionally active, thus performing kleptoplasty, which also results in a change of the host cytoplasm coloration. Given the seasonal transitions to long periods of darkness performed in high latitudes and leading to scarceness of primary production, one would expect foraminiferans to face absence of prey algae and starvation, the latter resulting in either death or dormancy of the most part of population. Nevertheless, our results contradict such assumptions. In January 2015 and 2016, during the Marine Night cruise with RV Helmer Hanssen, we collected live specimens in the Kongfjorden area, Svalbard. All major species (Nonionella labradorica, Islandiella helenae, Cassidulina reniforme, Elphidium excavatum, Elphidium bartletti) had brightly species-specifically colored cytoplasm implying they did not starve but had access to algal food. Transmission electron microscopy revealed that all specimens had well-developed mitochondria, Golgi apparatus and endoplasmic reticulum, therefore being meta-bolically active throughout the winter season. Moreover, some foraminiferans possessed intact
chloroplasts within cytoplasm. These results strongly indicate that high Arctic benthic foraminifera are not dormant during the polar night, and they access algal diet.
Supported by Research Council of Norway grant 226417/E10 and RFBR grant 14-04-93083.
TIM17 FAMILY PROTEIN IN THE MITO-SOMES OF GIARDIAINTESTINALIS Kolisko M.1, Martincova E.2, Voleman L.2, Roger A.J.3 4, Dolezal P.2
1 - Canadian Institute for Advanced Research, Department ofBotany, University ofBritish Columbia, Vancouver, Canada
2 - BIOCEV — Biotechnology andBiomedicine Center of the Academy of Sciences and Charles University in Vestec and Department of Parasitology, Faculty of Science, Charles University in Prague, Czech Republic
3 - Centre forComparative Genomics and Evolutionary Bioinformatics, Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
4 - Program in Integrated Microbial Biodiversity, Canadian Institute for Advanced Research, Halifax, Nova Scotia, Canada [email protected]
Protein transport across the mitochondrial membranes is mediated by the TIM, TOM and SAM complexes. These complexes are common to all supergroups of eukaryotes suggesting that they were already present in the last eukaryotic common ancestor. However, mitochondria-related organelles of Giardia intestinalis known as mitosomes were thought to lack both the SAM (a beta barrel assembly complex in the outer membrane) and the TIM (the translocase of the inner membranes) their membranes. The question was, how proteins pass the inner mitosomal membrane. Here, we present the identification of Tim17 family protein in giardia mitosomes, which represents a core channel forming subunit of the TIM complex. The bioinformatic identification of this highly diverged subunit was only possible by including newly obtained orthologous metamonad sequences in the sequence profiles. We demonstrate that giardia Tim17 is specifically targeted to mitosomes, where it interacts with other proteins involved in the protein transport and the iron-sulfur cluster assembly.
HETEROTROPHIC NANOFLAGELLATES IN THE PLANKTON OF LAPTEV SEA Kopylov A.I.1, Zabotkina E.A.1, Kosolapova N.G.1, Romanenko A.V.1, Sazhin A.F.2 1 - Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Russia
Protistology ■ 37
2 - Shirshov'Institute ofOceanology, Russian Academy
of Sciences, Russia
The results of the species composition, abundance and biomass of heterotrophic nanoflagellates (HNF) were obtained for the first time in the Laptev Sea in August-September 2014-2015. An attempt was made to assess the role of HNF in grazing productions of bacterioplankton (PB) and virioplankton (PV). 24 species and forms of HNF 9 taxa and groups of uncertain systematic position were found. Kinetoplastea Honigberg, 1963 were characterized by the highest species diversity. The HNF community dominated by bacteriophages (eighteen species), also found four omnivorous and two carnivorous species. Nhnf ranged from 108-651 cells/ml, the biomass — 0.3-3.5 mg C/m3. NHNF was three orders of magnitude lower than NB, and BHNF was 1.6-63.3% (mean 24.4+4.0%) biomass of bacterioplankton. Between NHNF and NB were detected high positive correlation (R=0.63, p=0.05). The virus particles (diameter of 200-531 nm) potentially can be edible objects for HNF. However, the ratio of the number of large viruses at NHNF was low - 42-417. HNF could consume a significant amount of virus attached to the walls and inside bacteria. The number of bacteria with attached viruses was 8.7-26.5% NB. On bacteria it was up to 11 virus particles. The number ofbacteriophage-viruses in infected cells reached 111 particle/cell. Guided by literature data on clearance rates of water by Arctic HNF (Sherr et al., 1997), calculated that in the water column of the Laptev sea the HNF community consumed 1.1-30.4% (average 8.3%) daily PB and 1.3-77.2% (average 14.9%) the daily PV. The research supported by the RFBR grant 14-04-00130.
THE STATUS OF THE SPECIES BALANTI-DIUM ELONGATUM FROM THE GUT OF EUROPEAN COMMON FROG Kornilova O.A.1, Chistyakova L.V.2, Kostygov A. Yu.34
1 - Herzen State Pedagogical University of Russia, St. Petersburg
2 - Centre of Core Facility of SPSU "Culturing collections of microorganisms", St. Petersburg, Russia
3 - Zoological Institute of the Russian Academy of Sciences
4 - Life Science Research Centre, Faculty of Science, University of Ostrava
The representatives of the genus Balantidium Clapare de et Lachmann, 1858 have several common morphological features: sacciform or
slightly elongated body completely covered with cilia forming dense longitudinal rows. In the anterior part of the body, there is an opening of vestibulum. Such features are clearly visible under light micro-scope. Because balantidia have very few other morphological characters suitable for taxonomy, their species identity is usually determined using morphometric data. Comparative analysis of several described Balantidium spp. indicated that many of these specific names might be synonyms. All balantidia inhabiting the intestine of mammals and birds were recognized to belong to a single species — Balantidium coli, recently moved to the genus Balantioides Alexeieff, 1931. We supposed that some species from amphibians may be synonyms (balantidia are polymorphic) and some of them may belong to different genera. For solving this issue, we used modern electron microscopic techniques and molecular phylogenetic analysis. We studied the morphology of Balantidium entozoon and B. elongatum from the gut of European common frog Rana temporaria Linnaeus, 1758 using light and electron microscopy. The distinguishing features of B. elongatum are the long thin fusiform body and relatively short vestibulum. However, other traits (number of kinetes and the distance between them) are indistinguishable between two species. Their intracellular structures also showed no differences. The sequences of 18S rRNA gene of both species were identical to each other and to that of B. entozoon from the GenBank. Thus B. elongatum must be considered as a younger synonym of B. entozoon.
BRIDGING THE GAP BETWEEN TRADITIONAL TAXONOMY AND TRANSCRIP-TOMICS IN ARCELLINIDS (AMOEBOZOA) Kosakyan Anush1, Brown Matthew W.2 3, Lara Enrique4, Mitchell Edward A.D.45, Lahr Daniel J.G.1
1 - Laboratory of Evolutionary Protistology, Institute of Biosciences, University of Sao Paulo, Matao, Travessa 14,Cidade Universitaria, 05508-090 - Sao Paulo, SP, Brasil
2 - Department ofBiological Sciences, Mississippi State University, Mississippi State, 39762, Mississippi, USA
3 - Institute for Genomics, Biocomputing and Biotechnology, Mississippi State University, Mississippi State, 39762, Mississippi, USA
4 - Laboratory ofSoilBiology, University ofNeuchatel, Rue Emile-Argand 1, 2000 Neuchatel, Switzerland
5 - Jardin Botanique de Neuchatel, Chemin du Perthuis-du-Sault 58, 2000Neuchatel, Switzerland. [email protected]
