An aerobic, pink-pigmented, budding and rosette-forming bacterium was isolated from an acidic Sphagnum peat bog and designated strain A10T. The 16S rRNA gene sequence analysis showed that strain A10T was a member of the order Planctomycetales and belonged to a phylogenetic lineage defined by the genus Gemmata, with 90 % sequence similarity to that of Gemmata obscuriglobus, the only taxonomically described organism of this group. Ellipsoid-shaped cells of strain A10T were uniformly covered with crateriform pits and possessed long (up to 10–15 μm) and unusually thick (0.5–0.7 μm) stalks of a unique ultrastructure. Thin sections revealed a complex intracellular membrane system compartmentalizing the cells. Strain A10T was a moderately acidophilic, mesophilic organism capable of growth at pH values between 3.8 and 7.2 (with an optimum at pH 5.5–6.0) and at temperatures between 10 and 30 °C (with an optimum at 20–25 °C). The major fatty acids were C18 : 0, C18 : 1 ω5c and C16 : 1 ω5c and the major quinone was MK-6. Cells of strain A10T contained high amounts of bound saturated and monounsaturated C26–C32 (ω-1) hydroxy fatty acids. The G+C content of the DNA was 62.5 mol%. The unique cell morphology, the capability of growth in acidic conditions and a number of chemotaxonomic and genotypic characteristics served to differentiate strain A10T from G. obscuriglobus. Based on these data, the novel isolate should be considered as representing a novel genus and species of planctomycetes, for which the name Zavarzinella formosa gen. nov., sp. nov. is proposed The type strain is A10T (=DSM 19928T=VKM B-2478T).
Deinococcus mumbaiensis DSM 17424T was compared with Deinococcus ficus CC-FR2-10T to clarify the taxonomic relationship between the two species. 16S rRNA gene sequence comparisons demonstrated that these strains share 99.5 % sequence similarity. Investigation of fatty acid patterns and substrate utilization profiles displayed no striking differences between the type strains of the two species. DNA–DNA hybridizations between the two strains showed 75.4 % (76.6 %) relatedness. Therefore, the reclassification of Deinococcus mumbaiensis as a later heterotypic synonym of Deinococcus ficus is proposed, based upon the estimated phylogenetic position derived from 16S rRNA gene sequence data, fatty acid and biochemical data and DNA–DNA hybridization results.