Thalassobellus suaedae gen. nov., sp. nov., a marine bacterium of the family Flavobacteriaceae isolated from a halophyte Suaeda japonica.

Abstract

Two Gram-stain-negative, facultative anaerobic, rod-shaped and non-gliding bacteria, designated as HL-DH10^T and HL-DH14, were isolated from the halophyte Suaeda japonica in a mudflat, Republic of Korea. Based on the results of 16S rRNA gene pairwise analysis, the two isolates were the members of the family Flavobacteriaceae, and Aestuariibaculum suncheonense SC17^T was the most closely related to strains HL-DH10^T and HL-DH14 with 96.3% and 95.4% sequence similarity, respectively. The average nt identity and digital DNA-DNA hybridization values between strains HL-DH10^T and HL-DH14 and other related species were all less than 79.2% and 21.9%, respectively. The genomic DNA G+C contents of strains HL-DH10^T and HL-DH14 were 32.0% and 31.5%, respectively. Cells of these strains showed optimal growth at 25 °C, pH 6.5-7.0 and 2.5-4.0% (w/v) sea salts. The major respiratory quinone was menaquinone-6. The major cellular fatty acids were iso-C_15:0 (14.0-16.0%), iso-C_15:1 G (10.0-12.0%), iso-C_17:0 3-OH (12.4-13.9%), iso-C_15:0 3-OH (11.8-14.9%) and anteiso-C_15:0 (9.4-10.6%). The polar lipids consisted of phosphatidylethanolamine, an unidentified aminophospholipid, two to three unidentified aminolipids and three unidentified lipids. The comprehensive phylogenetic, genomic, phenotypic and chemotaxonomic results indicate that strains HL-DH10^T and HL-DH14 are considered to represent a novel genus of Flavobacteriaceae. Hence, we propose the novel genus Thalassobellus suaedae gen. nov., sp. nov. The type strain is HL-DH10^T (=KCCM 90512^T=JCM 36598^T).