Four novel Gram-stain-positive, endospore-forming bacteria of the order Clostridiales were isolated from subsurface sediments sampled during International Ocean Discovery Program Expedition 347 to the Baltic Sea. One strain (59.4MT) grew as an obligate heterotroph by aerobic respiration and anaerobically by fermentation. Optimum growth was observed with 0.5 % NaCl at 25 °C and pH 7.0–7.3. Analysis of 16S rRNA gene sequences of 59.4MT revealed Alkaliphilus transvaalensis (92.3 % identity), Candidatus Geosporobacter ferrireducens (92.2 %), Geosporobacter subterraneus (91.9 %) and Alkaliphilus peptidifermentans (91.7 %) to be the closest relatives. On the basis of the results of phenotypic and genotypic analyses, we propose that strain 59.4MT represents a novel species within a novel genus, Marinisporobacter balticus gen. nov., sp. nov., with the type strain 59.4MT (=DSM 102940T=JCM 31103T). Three other strains, 59.4F, 59.4BT and 63.6FT, were affiliated with the genus Desulfosporosinus and grew as strictly anaerobic sulfate reducers. These strains additionally used thiosulfate, elemental sulfur, sulfite and DMSO as electron acceptors and hydrogen as an electron donor. Strains 59.4F and 59.4BT had identical 16S rRNA gene sequences, which were most similar to those of Desulfosporosinus lacus (97.8 %), Desulfosporosinus hippei (97.3 %) and Desulfosporosinus orientis (97.3 %). Strain 63.6FT was closely related to D. lacus (97.7 %), Desulfosporosinus meridiei (96.6 %) and D. hippei (96.5 %). The similarity of 16S rRNA gene sequences of strains 59.4BT and 63.6FT was 96.6 %. We propose the new names Desulfosporosinus nitroreducens sp. nov., incorporating strain 59.4F (=DSM 101562=JCM 31104) and the type strain 59.4BT (=DSM 101608T=JCM 31105T), and Desulfosporosinus fructosivorans sp. nov., with the type strain 63.6FT (=DSM 101609T=JCM 31106T).
Three strains, CBM1T, CBH23 and LAH16T, belonging to the genus Paenibacillus were isolated from the midgut and hindgut of Apis mellifera. Based on 16S rRNA gene sequence analyses and phenotypic characteristics, the three strains represent two novel species. Strains CBM1T and CBH23 formed a group with Paenibacillus puldeungensis CAU 9324T, and strain LAH16T belonged to the Paenibacillus amylolyticus NRRL NRS-290T subgroup of the genus Paenibacillus . The DNA G+C contents of strains CBM1T, CBH23 and LAH16T were 47.7, 48.1 and 46.1 mol%, respectively. The three strains possessed diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine as polar lipids. The predominant quinone in the three strains was MK-7, but strains CBM1T and CBH23 contained an additional major quinone, MK-8(H2). While strain LAH16T and most species of the genus Paenibacillus possessed anteiso-C15 : 0, iso-C16 : 0 and C16 : 0 as major cellular fatty acids, strains CBM1T and CBH23 possessed C16 : 0, anteiso-C15 : 0, C18 : 1ω7c and C19 : 0cyclo ω8c. Based on phenotypic, chemotaxonomic and phylogenetic data, strains CBM1T and CBH23 and the strain LAH16T represent novel species in the genus Paenibacillus , for which the names Paenibacillus apis sp. nov. and Paenibacillus intestini sp. nov. are proposed, with CBM1T (=KCTC 33844T=JCM 31620T) and LAH16T (=KCTC 33832T=JCM 31621T) as the type strains, respectively.
A facultatively anaerobic, Gram-stain-positive bacterium, designated ETRF1T, was found in faecal material of a timber rattlesnake (Crotalus horridus). Based on a comparative 16S rRNA gene sequence analysis, the isolate was assigned to the genus Enterococcus . The 16S rRNA gene sequence of strain ETRF1T showed >97 % similarity to that of the type strains of Enterococcus rotai , E. caccae , E. silesiacus , E haemoperoxidus , E. ureasiticus , E. moraviensis , E. plantarum , E. quebecensis , E. ureilyticus , E. termitis , E. rivorum and E. faecalis . The organism could be distinguished from these 12 phylogenetically related enterococci using conventional biochemical testing, the Rapid ID32 Strep system, comparative pheS and rpoA gene sequence analysis, and comparative whole genome sequence analysis. The estimated in silico DNA–DNA hybridization values were <70 %, and average nucleotide identity values were <96 %, when compared to these 12 species, further validating that ETRF1T represents a unique species within the genus Enterococcus . On the basis of these analyses, strain ETRF1T (=CCUG 65857T=LMG 28312T) is proposed as the type strain of a novel species, Enterococcus crotali sp. nov.
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).