A Gram-staining-positive, strictly aerobic, spherical, non-motile, red-pigmented bacterium, designated strain MK03T, was isolated from a soil sample collected in South Korea. The taxonomic position of the novel strain was investigated using a polyphasic approach. In phylogenetic analyses based on 16S rRNA gene sequences, strain MK03T was placed in a clade formed by members of the genus Deinococcus in the family Deinococcaceae and appeared to be most closely related to Deinococcus aerolatus 5516T-9T (97.4 % sequence similarity), Deinococcus marmoris AA-63T (97.2 %), Deinococcus radiopugnans ATCC 19172T (97.2 %) and Deinococcus saxicola AA-1444T (96.9 %). The genomic DNA G+C content of the novel strain was 64.5 mol%. The chemotaxonomic characteristics of strain MK03T were typical of members of the genus Deinococcus : MK-8 was identified as the predominant respiratory quinine, the major fatty acids were C16 : 1ω7c, C15 : 1ω6c, C16 : 0 and C15 : 0, ornithine was found to be the diamino acid in the cell-wall peptidoglycan and the novel strain showed resistance to gamma radiation, with a D10 value (i.e. the dose required to reduce the bacterial population by 10-fold) in excess of 9 kGy. In hybridization experiments, only low DNA–DNA relatedness values (11.6–34.5 %) were recorded between the novel strain and its closest relatives in the genus Deinococcus . Based on the phylogenetic, chemotaxonomic, phenotypic and DNA–DNA relatedness data, strain MK03T represents a novel species of the genus Deinococcus , for which the name Deinococcus humi sp. nov. is proposed. The type strain is MK03T ( = KCTC 13619T = JCM 17915T).
Representatives of a new cyanobacterial genus, Toxopsis Lamprinou & Pantazidou gen. nov., were found in fresh material from Cave ‘Francthi’ (Peloponnese, Greece) and isolated in cultures. Ecological data relating to the environmental parameters of the sampling sites are provided, such as the photosynthetically active radiation (PAR), temperature and relative humidity. Morphological characteristics and the life cycle of the type species Toxopsis calypsus Lamprinou & Pantazidou sp. nov. were studied using light microscopy and scanning and transmission microscopy. Molecular analysis based on the 16S rRNA gene sequence was also conducted. Toxopsis calypsus sp. nov. is a false-branched nostocalean cyanobacterium with both isopolar and heteropolar filaments bearing mono-pored and bi-pored heterocysts, and also hormogonia and akinetes. Isopolar filaments adhere by the centre to the substrate and are found mainly in fresh material and in young cultures; heteropolar filaments bearing a basic mono-pore heterocyst are dominant in aged (more than one-year-old) cultures. According to the revised taxonomic classification system of Komárek & Anagnostidis (1989) [Komárek, J. & Anagnostidis, K. (1989). Algol Stud, 56, 247–345] based mainly on morphological data, the new genus described here shares morphological characters with both nostocalean families Scytonemataceae and Microchaetaceae, showing similarities in particular to Scytonematopsis contorta [Vaccarino, M. A. & Johansen, J. R. (2011). Fottea 11, 149–161], Microchaetaceae. Molecular data from the 16S rRNA sequence determined in this paper showed that Toxopsis calypsus sp. nov. is more related to the family Microchaetaceae, and the five phylotypes analysed by PCR showed that the closest nostocalean relatives are Tolypothrix distorta SAG 93.79 (GenBank accession no. GQ287651) and Coleodesmium sp. ANT.L52B.5 (AY493596) with 95–96 % and 96 % similarity, respectively. In contrast, the five phylotypes showed a distant similarity to Scytonematopsis contorta (<91 %). The phenotypic and genetic traits strongly supported the classification of the five phylotypes as a new taxon for which the name Toxopsis calypsus Lamprinou & Pantazidou gen. nov., sp. nov. is proposed.