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Protistology ■ 31
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3 - Natural History Museum, London, SW7 5BD, UK [email protected]
River Yamuna maintains a reasonably good quality from its origin in the Himalayas to its entry into the National Capital Region (NCR) of Delhi, India. 18 sewage drains carrying industrial and domestic wastes flow into the river in the 22 km stretch (1.6% of total length) as it flows through the NCR. 80% of the pollution in the river's total length of 1375 km occurs as it passes through the NCR, severely compromising its water quality. As free-living ciliated protist species differ widely in tolerance to pollutants, the present study was conducted to catalogue ciliate communities (with appropriate morphological, morphometric and morphogenetic descriptions) at two selected locations along the river, namely the point where the river enters the NCR (S1) and 500 m downstream of the site where the largest sewage drain empties into the river (S2). Physico-chemical parameters including heavy metal concentrations were analyzed in order to assess the water quality at these two locations. Compared to S1: the Biochemical Oxygen Demand and phosphate concentrations increased 5X at S2; total hardness, total dissolved solids, conductivity, turbidity and nitrates doubled at S2; total coliforms and faecal coliform increased 50X at S2; lead concentration increased 2X times and arsenic 3X at S2. There was a significant fall in the species richness and abundance of ciliated protists at S2. Ofthe hypotrichous ciliates, there was a significant loss of members of the family Oxytrichidae, whereas euplotid populations were maintained. The changes in ciliate community will be discussed with respect to water quality.
NEW DATA ON THE ULTRASTRUCTURE OF THE GENUS PARADERMAMOEBA: UNUSUAL FEEDING MODE AND PRESENCE OF CYTOPLASMIC MTOCS Kamyshatskaya O.G., Smirnov A.V. Departmentoflnvertebrate Zoology, Faculty of Biology, St. Petersburg State University, St. Petersburg, Russia [email protected] Naked amoebae engulf food objects via phagocytosis, and during this process the portion of cell membrane covered with the glycocalyx appears inside newly formed food vacuoles. Further cell has to restore membrane and reconstruct respective portion of the glycocalyx. It may be an energetically costly process for species possessing thick and highly differentiated glycocalyx. Genus Paradermamoeba (phylum Amoebozoa, class Discosea) includes two species — P. levis and P. valamo. Both possess highly differentiated cell coat composed of tightly
packed helical glycostyles, ca. 220 nm in thickness in P. levis and ca. 520 nm in P. valamo. Our study reveals that during formation of the food vacuole P. valamo resorbs cell coat at the area of contact with food object, thus avoiding digestion of glycocalyx elements. The similar feeding mode is known in other thick-coated amoebae, like Pellita and Dermamoeba. This observation confirms our earlier hypothesis, stating that thick-coated amoebae have to adopt special ways to avoid energetically costly digestion and further reconstruction of glycocalyx elements. We provide the first description of the cytoplasmic microtubule-organising centres (MTOCs) associated with dictyosomes ofthe Golgi complex in genus Paradermamoeba. This finding confirms the hypothesis that presence of cytoplasmic MTOCs is a synapomorphy of the phylogenetic lineages forming the subclass Longamoebia. Detailed study of the ultrastructure of P. levis reveals that so-called "supernumerary nucleus" of P. levis noted in the initial description is not an individual structure but an outgrowth of the cell nucleus containing its own nucleolus. Supported with RSF grant 14-14-00474.
ISOLATION OF FREE-LIVING AMOEBAE FROM SOUTHERN HAN-LIVER IN KOREA Kang H.K.12, Seong G.S.12, Sohn H.J.1-2, Jung S.Y.3, Lee S.E.4, Park M.Y.4, Shin H.J.12
1 - DepartmentofMicrobiology, Ajou University School of Medicine
2 - Department of Biomedical Science, Graduate School of Ajou University, Suwon 443-721, Republic of Korea
3 - Department of Biomedical Laboratory Science, Molecular Diagnostics Research Institute, School of Health and Medicine, Namseoul University, Cheonan 31020, Republic of Korea
4 - Division of Malaria and Parasitic Disease, Korea National Institute ofHealth, Osong363-951, Republic of Korea
Pathogenic Naegleria fowleri and Acanthamoeba spp., free-living amoebae exist in the natural environment, are causing agents of an acute and lethal primary amoebic meningoencephalitis (PAM) and amoebic keratitis (AK) in humans, respectively. To ascertain the existence of free-living amoebae in Korea, in late August 2015, water samples of eight sites were collected in Korean hydrosphere where water skiing and recreation have been actively performed, and then the non-nutrient agar culture and PCR-based detection technique were carried out. The surface waters were collected and filtered, and then final samples were cultured
32 • "PROTIST—2016
on non-nutrient agar medium with inactivated E. coli and subjected to PCR with various primer pairs (amplify mainly the 18S-small ribosomal RNA). Free-living amoebae were intensively detected by PCR in two collection regions (Yeoju and Yangpeong city around Southern Han-Liver). PCR products obtained from water samples of Yeoju and Yangpeong city were subjected to gene sequencing. The similarity of 18S-rRNA sequences were compared with various reference amoebae in GeneBank, and they showed 86-99% homology with N. gruberi, N. philippinensis, N. clarki, Acanthamoeba polyphagia and Vermamoeba vermiformis. A Korean isolate (confirmed by PCR as A. polyphagia) was isolated from Yeoju sample and have been subcultured in Nelson's and PYG liquid medium with 10% FBS at 30 °C incubator. In the in vitro cytotoxicity test, Korean isolate (tentative A. polyphagia) showed high cytotoxicity as much as reference amoebae, A. polyphagia and A. castellanii. This study will be useful, in the further study, for the detailed seasonal detection of free-living amoebae from Korean hydrosphere.
MORPHOLOGICAL AND GENETIC DIVERSITY OF OPISTHOSPORIDIA: NEW APHELID PARAPHELIDIUM TRIBONEMAE GEN. ET SP. NOV
Karpov S.A.12, Tcvetkova V.S.2, Mamkaeva M.A.2, Torruella G.3, Timpano H.3, Moreira D.3, LopezGarcia P.3
1 - Zoological Institute, Russian Academy ofSciences, Universitetskaya nab. 1, St. Petersburg 199034, Russian Federation
2 - St. Petersburg State University, Universitetskaya nab. 7/9, St. Petersburg 199034, Russian Federation
3 - Unité d'Ecologie, Systématique et Evolution, UMR CNRS 8079, Université Paris-Sud, 91405 Orsay cedex, France
Aphelids are a poorly known group of parasitoids of algae that have raised considerable interest due to their pivotal phylogenetic position. Together with Cryptomycota and the highly derived Microspo-ridia, they have recently re-classified as the Opistho-sporidia, which constitute the sister group to the fungi within the Holomycota. Despite their huge diversity, as revealed by molecular environmental studies, and their phylogenetic interest, only three genera have been described (Aphelidium, Amoeboaphelidium, and Pseudaphelidium), from which 18S rRNA gene sequences exist only for Amoeboaphelidium and Aphelidium species. Here, we present the molecular phylogeny, life cycle and ultrastructure of new freshwater aphelid, which is a new genus and species
Paraphelidium tribonemae. Molecular phylogenetic analysis of 18S rRNA gene sequences ofthis parasite indicates that P. tribonemae defines a distinct cluster which is only distantly related to Amoebaphelidium and Aphelidium, what confirms the wide genetic diversity ofthe aphelids. P. tribonemae has amoeboid opisthokont zoospores which are twice smaller than morphologically similar zoospores of Aphelidium aff. melosirae. Nonetheless, although the morphology of Paraphelidium species is generally similar to that of Aphelidium representatives, molecular phylogenetic analyses unambiguously show, that the two clades of strains are distantly related and must define two distinct genera.
We thank RFBR grant No. 15-29-02734 for financial support, and for cultivation of strains and access to the EM facilities the Center for Culturing Collection of Microorganisms and the Research Resource Center for Molecular and Cell Technologies (RRC MCT) of Research park of St. Petersburg State University correspondingly.
AN EVOLUTIONARY TRANSITION OF CHLOROPLAST DEGRADATION IN EU-GLENOIDS: HETEROTROPHIC DIGESTION TO SECONDARY PLASTID SENESCENCE Kashiyama Y.12, Kawahara J.1, Maruyama M.1, Kayama M.1, Nakazawa M.3, Tanifuji G.4, Yoko-yama A.5, Ishikawa T.6, Tamiaki H.2, Suzaki T.7
1 - Fukui University of Technology
2 - Ritsumeikan University
3 - Osaka Prefecture University
4 - National Museum of Nature and Science
5 - National Institute for Environmental Studies
6 - Shimane University
7 - Kobe University [email protected]
Establishments of regulatory mechanisms for the integrated endosymbiont must have been key steps in organelle acquisitions, where both endosymbiont and host processes cooperated to evolve new functions. Specifically important for the chloroplast is to establish regulatory mechanisms for chlorophyll-related metabolisms since the phototoxicity of chlorophyll would cause fatal damages. In particular, regulated degradation of chloroplasts or chloroplast dismantlement is critical not only for recycling nutrients but also for disposing the phototoxic chlorophylls safely. Unlike land plants, little has been understood for algae on chloroplast dismantlement and associated chlorophyll catabolism. We previously reported that the phototrophic euglenoid accumulates 132,173-cyclopheophorbide enols (CPEs) within their cells; CPEs are non-phototoxic catabolites
