Characterization of phototrophic microorganisms and description of new cyanobacteria isolated from the saline-alkaline crater-lake Dziani Dzaha Cellamare M. auteur aut IRD Duval C. auteur aut IRD Drelin Y. auteur aut IRD Djediat C. auteur aut IRD Touibi N. auteur aut IRD Agogue H. auteur aut IRD Leboulanger Christophe auteur aut IRD Ader M. auteur aut IRD Bernard C. auteur aut IRD text journalArticle eng text/pdf born digital access The saline-alkaline crater-lake Dziani Dzaha (Mayotte, Indian Ocean) is dominated by the bloom-forming cyanobacterium Arthrospira. However, the rest of the phototrophic community remains underexplored because of their minute dimension or lower biomass. To characterize the phototrophic microorganisms living in this ecosystem considered as a modern analog of Precambrian environments, several strains were isolated from the water column and stromatolites and analyzed using the polyphasic approach. Based on morphological, ultrastructural and molecular (16S rRNA gene, 18S rRNA gene, 16S-23S internal transcribed spacer (ITS) region and cpcBA-IGS locus) methods, seven filamentous cyanobactena and the prasinophyte Ptcocystis salinarum were identified. Two new genera and four new cyanobacteria species belonging to the orders Oscillatoriales (Desertifilum dzianense sp. nov.) and Synechococcales (Sodalinema komareku gen. nov., sp. nov., Sodaleptofyngbya stromatolitii gen. nov.., sp. nov. and Haloleptolyngbya elongata sp. nov.) were described. This approach also allowed to identify Arthrospira fusiformis with exclusively straight trichomes instead of the spirally coiled form commonly observed in the genus. This study evidenced the importance of using the polyphasic approach to solve the complex taxonomy of cyanobactena and to study algal assemblages from unexplored ecosystems. specialized cyanobacteria microalgae crater-lake saline-alkaline lake polyphasic approach Arthrospira OCEAN INDIEN MAYOTTE DZIANI DZAHA LAC 034 020 FEMS Microbiology Ecology 94 8 fiy108 [25 p.] 2018 0168-6496 https://www.documentation.ird.fr/hor/fdi:010073756 10.1093/femsec/fiy108 0168-6496 [F B010073756] https://www.documentation.ird.fr/hor/fdi:010073756 https://www.documentation.ird.fr/intranet/publi/2018/08/010073756.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2018-09-12 2023-07-11 fdi:010073756 fre