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Protistology ■ 89
divergence ancient MCS tethers were lost while others were gained in a lineage-specific manner.
UNRAVELLING THE DIVERSITY OF DIPLO-NEMIDS BY CULTURE-BASED TAXONO-MIC STUDY
Yabuki A.1, Kusaka C.1, Votypka J.23, Horak A.3, Lukes J.3, Fujikura K.1
1 - Department ofMarine Biodiversity Research, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan
2 - Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
3 - Biology Centre, Institute of Parasitology, Czech Academy of Sciences and Faculty of Sciences, University of South Bohemia, Ceske Budejovice (Budweis), Czech Republic [email protected]
Diplonemids (Diplonemida) belong to the phylum Euglenozoa and they are unicellular flagellates that are free-living or parasitize algae and invertebrates. Although Diplonemida included for decades only the genera Diplonema and Rhynchopus yet, the genus Hemistasia was recently transferred to Diplonemida based on the phylogenetic analysis. Hemistasia phaeocysticola is a representative of a large environmental clade that remained to be identified in Diplonemida. Members of this environmental clade have attracted attention not only from taxonomic/phylogenetic perspective, but also due to highly unusual RNA processing in their mitochondria, which is reminiscent oftrans-splicing and editing, so far reported only from them. Hence, the studies focusing on H. phaeocysticola and the other members of this environmental clade may expand our knowledge about the structural diversity and evolutionary history ofunusual structural genes in this protist group. We have isolated new marine diplonemids and keep some of them in culture. In the present study, we report their morphology and phylogenetic positions in Diplonemida: some cultures branch within the clade that is composed of environmental sequences and H. phaeocysticola, while others are also shown to be novel lineages in the clade of Diplonema and Rhynchopus. Our findings significantly expand the known diversity of diplonemids and it is also suggested that the classification system under Diplonemida should be revised: the establishment ofa novel family is possibly needed for the members ofthe environmental clade.
RED ALGAL PHYLOGENYAND EVOLUTION BASED ON MITOCHONDRIAL GENOME Yang E.C.1, Lee J.2, Yoon H.S.2 1 - Korea Institute of Ocean Science & Technology,
Ansan 15627, Korea
2 - Department of Biological Sciences, Sungkyunkwan University, Suwon 16419, Korea [email protected]
The Florideophyceae (5 subclasses and 31 orders) and Bangiophyceae (1 subclass and 1 order) distribute in both marine and freshwater habitats, and cover the most described red algal diversity, ca. 7,100 species (98% of Rhodophyta). The monophyly those two classes and relationships among subclasses were well-supported in many phylogenetic analyses, however, interordinal phylogeny remain largely unknown in the subclass Rhodymeniophycidae. In order to resolve ordinal relationships and evolution of the subclass, we have determined 11 mitochondrial genomes (mtDNA) from representative species and compared with published data. Concatenated phylogeny based on 37 mtDNA (6,345 aminoi acid data) of red algae showed stronger support among order level than previous studies. The mtDNA synteny comparison showed 47 events of gene evolution (indel and rearrangement) among Bangiophyceae, Hiden-brandiophycidae, Nemaliophycidae, Corallino-phycidae, Ahnfeltiophycidae, and Rhodymenio-phycidae. We demonstrate that all rhodymeniophy-cidan mtDNA have conserved architectures with little variation of contents. Based on the best phylogeny, we inferred the ancestral mtDNA content, evolution and reduction of protein coding genes in red algae.
NEW MITOCHONDRIAL GENOMES AND MOLECULAR MARKERS FOR THE COASTAL DIATOMS OF KOREA Yang E.C., Noh J.H.
Korea Institute ofOcean Science & Technology, Ansan
15627, Korea
The Bacillariophyceae is the largest class of the stramenopiles (ca. 11,200 species), and one of the most important and abundant primary producers of the aquatic ecosystem. Diverse diatoms are occurred in inter-tidal mudflats of the west coast of Korea, the Yellow Sea. In spite of ecological importance ofthe phytoplankton community, there are a little number of molecular markers have been developed, such as nuclear encoded 18S rRNA (SSU) and plastid encoded rbcL. In present study, we determined two new mitochondrial genome (mtDNA) of common tube-dwelling diatoms, Berkeleya fennica TA424 (GenBank accession NC_026126, 35.509 bp) and Navicula ramosissima TA439 (48,652 bp) isolated from the Taean mudflat (36°44'14.79"N 126°10'41.89"E), and one mtDNA
90 • "PROTIST—2016
of pelagic diatom, Skeletonema marinoi JK029 (NC_028615, 38,515 bp) isolated from an interdidal site ofthe Sihwaho (37°18'38.91"N 126°36'16.35"E). Complete mtDNA of each species shows typical bacillariophycean mitochondrial contents, including of35-42 coding sequences (CDS), 2 ribosomal RNA (rRNA), and 25-26 transfer RNA (tRNA) genes. All CDS ofmtDNA aligned with all available diatoms data, including Phaeodactylum tricornutum (NC_016739), Fragilaria acus (NC_013710), and Thalassiosira pseudonana (NC_007405). Based on the saturation test and preliminary sequencing, we suggest mitochondrial markers for diatoms survey on the west coast of Korea.
HORIZONTAL TRANSFER OF A NOVEL SIX-GENE OPERON FROM A BACTERIUM INTO THE PLASTID GENOME OF EUSTIG-MATOPHYTE ALGAE
Yurchenko T.12, Sevcikova T.1, Strnad H.3, Butenko A.1, EliaS M.12
1 - University ofOstrava, Faculty ofScience, Department of Biology and Ecology, Life Science Research Centre, Ostrava, Czech Republic
2 - University ofOstrava, Faculty ofScience, Institute of Environmental Technologies, Ostrava, Czech Republic
3 - Institute ofMolecular Genetics, Czech Academy of Sciences, Prague, Czech Republic [email protected]
Genes in plastid genomes (plastomes) have been primarily inherited from the cyanobacterial plastid ancestor, but cases of genes acquired by horizontal gene transfer (HGT) have been occassionally reported from plastomes of different algal lineages. Here we report an interesting case of HGT-mediated gene acquisition revealed by sequencing plastomes of the eustigmatophyte algae Monodopsis sp. MarTras21 and Vischeria sp. CAUP 202. While the gene complement of the newly and previously sequenced eustigmatophyte plastomes proved to be highly conserved, those of Monodopsis sp. and Vischeria sp. harbour a cluster of six genes not reported from any plastid genome sequenced so far. All six genes have homologs in various bacteria, where they are usually organized in the same six-gene cluster, i.e. a putative operon. Phylogenetic analyses showed that the cluster from eustigmatophyte plastomes is nested among sequences from the order Cytophagales (phylum Bacteroidetes), with the cluster from Sporocytophaga myxococcoides constituting a robustly resolved sister group to the eustigmatophyte clade. Sequence analyses using different homology-detection tools failed to detect functionally characterized homologs of the protein
encoded by the first gene of the operon, whereas the remaining five proteins could be assigned only to broader enzyme superfamilies. Nevertheless, based on these analyses we speculate that the newly detected operon encodes enzymes of a pathway synthesizing a prenylated aromatic compound, possibly an antimicrobial or other protective substance. To our knowledge, this is the first report of an expansion ofthe metabolic capacity of a plastid mediated by HGT into the plastome.
SPECIES DIVERSITY AND MORPHOLOGY
OF CENTROHELID HELIOZOANS OF SOME
SITES IN EUROPEAN PART OF RUSSIA AND
SOUTH-EAST UKRAINE
Zagumyonnyi D.G.
Voronezh State University, Russia
The species composition and cytoskeleton morphology of centrohelid heliozoans from different water biotopes ofEuropean Russia and South-East Ukraine have been investigated. 21 species from 6 genera and 3 families have been found. Two forms (Acanthocystis sp. nov. 1. and Acanthocystis sp. nov. 2.) have appeared to be as new species. Following species Acanthocystis turfacea, Heterophrys myriopoda, Polyplacocystis symmetrica, Polyplacocystis coerulea, Acanthocystis dentate have been marked for SouthEast Ukraine for the first time. Also Acanthocystis dentata, Raineriophrys fortesca, Raineriophrys kilianii, Pterocystis foliaea and Pterocystis pulchra have been found for the Central Russia for the first time. Pterocystis pulchra has been revealed for heliozoan fauna of Russia firstly at all. Heterophrys marina has been found in fresh waters of Russia. Polyplacocystis symmetrica has been found in slightly salted biotopes. The morphological descriptions of all studied species have been given. New data on spicule structures of Acanthocystis dentate have been done. Most frequent species was Acanthocystis pectinata. This study was supported by the Russian Scientific Foundation (grant nos. 14-14-00515).
RUBISCO IN NON-PHOTOSYNTHETIC ALGA EUGLENA LONGA: DIVERGENT FEATURES, TRANSCRIPTOMIC ANALYSIS AND REGULATION OF COMPLEX FORMATION Zahonova K.1, Fussy Z.2, Obornik M.234, Elias M.1, Yurchenko V.12
1 - Life Science Research Centre, Department of Biology and Ecology and Institute of Environmental Technologies, Faculty of Science, University of Ostrava, 701 00 Ostrava, Czech Republic
2 - Institute of Parasitology, Biology Centre ASCR, 370 05 Ceske Budejovice, Czech Republic
