Defluviitalea raffinosedens sp. nov., a thermophilic, anaerobic, saccharolytic bacterium isolated from an anaerobic batch digester treating animal manure and rice straw

A thermophilic, anaerobic, fermentative bacterium, strain A6(T), was obtained from an anaerobic batch digester treating animal manure and rice straw. Cells were Gram-stain-positive, slightly curved rods with a size of 0.6–1×2.5–8.2 µm, non-motile and produced terminal spores. The temperature, pH and NaCl concentration ranges for growth were 40–60 °C, 6.5–8.0 and 0–15.0 g l(−1), with optimum growth noted at 50–55 °C, pH 7.5 and in the absence of NaCl, respectively. Yeast extract was required for growth. d-Glucose, maltose, d-xylose, d-galactose, d-fructose, d-ribose, lactose, raffinose, sucrose, d-arabinose, cellobiose, d-mannose and yeast extract were used as carbon and energy sources. The fermentation products from glucose were ethanol, lactate, acetate, propionate, butyrate, valerate, iso-butyrate, iso-valerate, H(2) and CO(2). The G+C content of the genomic DNA was 36.6 mol%. The predominant fatty acids were C(16 : 0), iso-C(17 : 1), C(14 : 0), C(16 : 1)ω7c, C(16 : 0) N-alcohol and C(13 : 0) 3-OH. Respiratory quinones were not detected. The polar lipid profile comprised phosphoglycolipids, phospholipids, glycolipids, a diphosphatidylglycerol, a phosphatidylglycerol and an unidentified lipid. Phylogenetic analyses of the 16S rRNA gene sequence indicated that the strain was closely related to Defluviitalea saccharophila DSM 22681(T) with a similarity of 96.0 %. Based on the morphological, physiological and taxonomic characterization, strain A6(T) is considered to represent a novel species of the genus Defluviitalea, for which the name Defluviitalea raffinosedens sp. nov. is proposed. The type strain is A6(T) (=DSM 28090(T)=ACCC 19951(T)).