A novel thermophilic, anaerobic and organotrophic bacterium, designated strain MC3T, was isolated from a coastal thermal spring on Île Saint-Paul in the Southern Indian Ocean. Cells of strain MC3T were motile rods, 0.8–1.0 μm wide and 1.0–2.4 μm long during exponential phase and up to 7.0 μm long during stationary phase. Strain MC3T was an anaerobic organotroph able to use diverse organic compounds. It was also able to reduce sulfur to sulfide. Growth was observed at temperatures ranging from 45 to 70 °C (optimum at 60 °C), between pH 5.5 and 7.5 (optimum at pH 6) and from 8 to 46 g NaCl l−1 (optimum at 26 g l−1). The total G+C content of the genomic DNA was 26.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequence comparisons indicated that strain MC3T was affiliated with the genus Marinitoga within the order Thermotogales. It shared 94.4–95.7 % 16S rRNA gene sequence similarity with strains of other Marinitoga species; Marinitoga hydrogenitolerans was found to be the most closely related organism. Based on the data from the phylogenetic analysis and the physiological properties of the novel isolate, strain MC3T should be classified as a representative of a novel species, for which the name Marinitoga litoralis sp. nov. is proposed; the type strain is MC3T (=DSM 21709T =JCM 15581T).
We isolated from compost an aerobic, thermophilic, Gram-stain-positive, spore-forming bacterium that formed branched vegetative and aerial mycelia. This strain, designated SK20-1T, grew at 31–58 °C, with optimum growth at 50 °C, while no growth was observed below 28 or above 60 °C. The pH range for growth was 5.4–8.7, with optimum growth at pH 7.0, while no growth was observed below pH 5.0 or above pH 9.1. Strain SK20-1T was able to hydrolyse polysaccharides such as cellulose, xylan and chitin. The DNA G+C content was 54.0 mol%. The major fatty acid was iso-C17 : 0 and the major menaquinone was MK-9(H2). The cell wall contained glutamic acid, serine, alanine and ornithine in a molar ratio of 1.00 : 1.07 : 2.64 : 0.83. The polar lipids consisted of phosphatidylinositol, phosphatidylinositol mannosides, phosphatidylglycerol, diphosphatidylglycerol and an unknown glycolipid. Cell-wall sugars were rhamnose and mannose. Detailed phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SK20-1T belongs to the class Ktedonobacteria, and that the strain is most closely related to Ktedonobacter racemifer SOSP1-21T (88.5 %). On the basis of its phenotypic features and phylogenetic position, we propose that SK20-1T represents a novel genus and species, Thermosporothrix hazakensis gen. nov., sp. nov., within the new family Thermosporotrichaceae fam. nov. The type strain of Thermosporothrix hazakensis is strain SK20-1T (=JCM 16142T =ATCC BAA-1881T). In addition, we propose an emended description of the class Ktedonobacteria to classify the class in the phylum Chloroflexi.
Twenty-one homofermentative lactic acid bacteria were isolated from fermented cummingcordia (pobuzihi), a traditional food in Taiwan. The isolates had identical 16S rRNA gene sequences that were distinct from those of other lactobacilli, and their closest neighbours in the 16S rRNA gene sequence phylogenetic tree were strains of Lactobacillus acidipiscis. Levels of DNA–DNA relatedness between representative pobuzihi isolates and strains of L. acidipiscis were 17 % and below. Furthermore, the new isolates could be differentiated clearly from L. acidipiscis NBRC 102163T and NBRC 102164 in terms of acid production from l-arabinose, rhamnose, mannitol, lactose and 5-ketogluconate. It was concluded that the new isolates represent a single novel species of the genus Lactobacillus, for which the name Lactobacillus pobuzihii sp. nov. is proposed. The type strain is E100301T (=RIFY 6501T =NBRC 103219T =KCTC 13174T).