Tumebacillus amylolyticus sp. nov., isolated from garden soil in Korea

Abstract

A starch-degrading novel strain, designated as strain ITR2(T), was isolated from a soil sample collected from a garden near Dongguk University located in Goyang, Republic of Korea. The strain was identified as Gram-stain-positive, rod-shaped, and motile by means of peritrichous flagella. Moreover, 16S rRNA gene analysis revealed the novel strain to form a separate clade with Tumebacillus permanentifrigoris Eur1 9.5(T) (98.3%) while also clustering with Tumebacillus flagellatus GST4(T) (97.9%). Strain ITR2(T) grew optimally at temperatures of 20-30 degrees C, at pH 6.0-7.0 and at NaCl concentrations of 0-1%. The sole quinone was menaquinone-7 and the cell-wall peptidoglycan comprised alanine, aspartic acid, glutamic acid, lysine and meso-diaminopimelic acid (type-A1. peptidoglycan). The major fatty acids (>10%) of the novel strain were C 16:0, iso-C 14:0, iso-C 15:0 and anteiso-C 15:0, while the major polar lipids were phosphatidylmonomethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol and one unidentified phospholipid. Other polar lipids of the novel strain included, two unidentified glycolipids, three unidentified phospholipids and one unidentified lipid. The in silico DNA-DNA hybridization values between strain ITR2(T) and its reference strains (T. permanentifrigoris DSM 18773(T) and T. flagellatus GST4(T)) were 21.3 and 23.9 %, respectively, while the average nucleotide identity values were 78.5 and 81.2%, respectively. The genomic DNA G+C content was 54.9 mol%. Based on the phylogenetic, chemotaxonomic and genomic data obtained in the present study, we propose Tumebacillus amylolyticus sp. nov. to be a novel species within the genus Tumebacillus. The type strain is ITR2(T) (=KCTC 43280(T)=NBRC 114753(T)).