Scopulibacillus Daqui Sp Nov., A Thermophilic Bacterium Isolated From High Temperature Daqu

A Gram-stain-positive, facultatively anaerobic, thermophilic bacterium, designated ZQ18-1(T), was isolated from a high temperature daqu sample collected from the sesame-flavour liquormaking process. Oval endospores were formed at the centre of cells with swollen sporangia. The isolate was able to grow at temperatures of 20-60 degrees C (optimum growth at 50 degrees C), at pH 4-9 (optimum growth at pH 8) and in the presence of 0-10% (w/v) NaCl (optimum growth with 2% NaCl). Glucose and galactose were major cell-wall sugars, and meso-diaminopimelic acid was the diagnostic amino acid. The major polar lipids consisted of phosphatidylglycerol, diphosphatidylglycerol and three glycolipids. The major cellular fatty acids were anteiso-C-17 (:) (0) and iso-C-16 (:) (0), and the predominant menaquinone was MK-7. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain ZQ18-1(T) was most closely related to Scopulibacillus darangshiensis DLS-06(T), Pullulanibacillus pueri YN3(T), Tuberibacillus calidus 607(T), Pullulanibacillus naganoensis ATCC 53909 T, Pullulanibacillus uraniitolerans UG-2(T), Sporolactobacillus terrae DSM 11697 (T) and Sporolactobacillus inulinus NRIC 1133(T). Strain ZQ18-1(T) showed low DNA-DNA relatedness (40.7, 23.1, 46.5, 27.2, 45.6, 33.7 and 55.1 %) with the strains mentioned above. Based on morphological characteristics, chemotaxonomic characteristics, DNA-DNA hybridization data and physiological properties, strain ZQ18-1(T) represents a novel species of the genus Scopulibacillus, for which the name Scopulibacillus daqui sp. nov. is proposed. The type strain is Scopulibacillus daqui ZQ18-1(T) (=DSM 28236(T) =CICC 10824(T)). An emended description of the genus Scopulibacillus is provided.