A novel alkaliphilic spore-forming bacterium was isolated from the benthic sediments of the highly mineralized steppe Lake Khilganta (Transbaikal Region, Russia). Cells of the strain, designated Х-07-2T, were straight to slightly curved rods, Gram-stain-positive and motile. Strain Х-07-2T grew in the pH range from 7.0 to 10.7 (optimum pH 9.6–10.3). Growth was observed at 25–47 °C (optimum 30 °C) and at an NaCl concentration from 5 to 150 g l−1 with an optimum at 40 g l−1. Strain Х-07-2T was a chemo-organoheterotroph able to reduce amorphous ferric hydroxide, Fe(III) citrate and elemental sulfur in the presence of yeast extract as the electron donor. It used tryptone, peptone and trypticase with Fe(III) citrate as the electron acceptor. The predominant fatty acids in cell walls were C16:1ω8, iso-C15:0, C14 : 0 3-OH and C16 : 0. The DNA G+C content was 32.6 mol%. 16S rRNA gene sequence analysis revealed that strain Х-07-2T was related most closely to members of the genus Alkaliphilus within the family Clostridiaceae . The closest relative was Alkaliphilus peptidifermentans Z-7036T (96.4 % similarity). On the basis of the genotypic, chemotaxonomic and phenotypic data, strain Х-07-2T represents a novel species in the genus Alkaliphilus , for which the name Alkaliphilus namsaraevii sp. nov. is proposed. The type strain is Х-07-2T (=VKM В-2746Т=DSM 26418Т).

A psychrotolerant facultative anaerobe, strain SKBGT, was isolated from the bottom sediments of the cold mineral spring Buxichen (Buryatia, Russia). Gram-positive non-motile cocci with a diameter of 1.75–2.5 µm were observed singly or in long chains. Cells grew in the temperature range from ̶ 5–35 °C. Growth was observed within the pH range of 7.0–9.5, with the optimum growth at pH 7.6 and at a NaCl concentration from 0–1.0 % (optimum 0.1 % (w/v)). Strain SKBGT was a chemoorganoheterotroph that used sugars and some organic acids as substrates. The predominant fatty acids in cell walls were С16:1ω9, С18:1ω9, and С16 : 0. The 16S rRNA gene sequence of strain SKBGT shared high similarity (>99 %) with those of the type strains of the genus Trichococcus . Digital DNA–DNA hybridization (dDDH) and average nucleotide identity (ANI) values between strain SKBGT and Trichococcus shcherbakoviae ArtT (=DSM 107162T=VKM B-3260T) were 70.1 and 95.4 %, respectively. The genomic DNA G+C content of strain SKBGT was 47.1 mol%. Compared with the type strain of T. shcherbakoviae , the new strain was characterized by a temperature optimum for growth (10 °C) significantly lower than that of T. shcherbakoviae DSM 107162T (20–30 °C). Based on phenotypic and genomic characteristics, the isolate SKBGT was classified as T. shcherbakoviae subsp. psychrophilus subsp. nov. The type strain is SKBGT (=VKM B-3241Т=JCM 33326T).

An obligately anaerobic bacterium, strain Bkl1^T, was isolated from an enrichment culture of iron-reducing bacteria (IRB) obtained from a sample of the bottom sediments of the cold freshwater Lake Baikal (Russia). Cells of the strain were Gram-stain-negative, motile, spore-forming straight rods (0.6–0.7 × 2.0–7.0 µm) with a fermentative metabolism. Strain Bkl1^T grew in the temperature range from 7 to 38°C (optimum 20°C) and at pH 7.0–9.5 (optimum pH 7.6). The novel isolate was capable to reduce ferric citrate (FC), anthraquinone-2,6-disulfonate (AQDS) and Cr(VI) in the presence of lactate as carbon source. Ferrihydrite was not reduced in the absence of AQDS. Based on its 16S rRNA gene sequence, strain Bkl1^T was affiliated to the family Sporomusaceae and, more specifically, to the genus Pelosinus. The strain was most closely related to Pelosinus fermentans DSM 17108^T (99.2%) and P. propionicus DSM 13327^T (99.1%). Genome relatedness indexes revealed that the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain Bkl1^T and its closest phylogenomic relative (P. fermentans DSM 17108^T) were 93.3 and 54.2%, respectively. The G + C content of the genome of strain Bkl1^T was 39.1 mol % and its size was 5.32 Mb with 4939 protein-coding genes. The predominant fatty acids in cell walls were С_15:1, С_17:1, and С_16:1. Based on the phylogenetic analyses and phenotypic differences between the novel isolate and type strains of the genus Pelosinus, strain Bkl1^T (=VKM B-3511^Т = JCM 39258^T) is proposed to represent a novel species Pelosinus baikalensis sp. nov.

Acerihabitans sp. type strain TG2 ^T (VKM B-3773 ^T ) is a gram-negative, anaerobic psychrophilic bacterium that was isolated from a tundra soil sample selected by the Bykovsky Peninsula (Russia). This report describes the generation and annotation of the 5.3 Mb draft genome sequence of Acerihabitans sp. strain TG2 ^T .