Marnyiella aurantia, gen. nov., sp. nov., a novel bacterial species of the family Weeksellaceae that could produce flexirubin type pigments.

ABSTRACT

Two Gram-stain-negative, non-spore-forming, rod-shaped, and obligately aerobic bacteria, designated strains CX-624T and cx-311, were isolated from soil samples in Qinghai Province, China. The two strains grew best at 28 °C on the plate with Tryptone soya agar (TSA). Cells formed circular, convex, translucent, smooth, and orange colonies with approximately 1.0 mm diameter after 2 days of incubation on TSA at 28 °C. The strains were oxidase-negative and catalase-positive. The predominant cellular fatty acids were iso-C15  0 and anteiso-C15  0, and major polar lipids included phosphatidylethanolamine, an unidentified aminophospholipid, four unidentified lipids and an aminolipid. MK-6 was the sole menaquinone in strain CX-624T. Comparative analysis of the nearly full-length 16S rRNA gene sequences showed strains CX-624T and cx-311 were member of the family Weeksellaceae, with the highest similarity to Kaistella haifensis H38T (96.66 %), Epilithonimonas pallida DSM 18015T (96.59 %), and Chryseobacterium gambrini DSM 18014T (96.53 %). Both phylogenetic analysis of the 16S rRNA gene and 177 core genes revealed that strains CX-624T and cx-311 formed an independent clade. Average nucleotide identity values (< 72.64 %), average amino-acid identity values (<72.61 %) and digital DNA-DNA hybridization (< 21.10 %) indicated that the strains CX-624T and cx-311 should constitute a novel genus. The DNA G+C contents of strains CX-624T and cx-311 were 43.0 mol% and 42.7 mol%. According to the data obtained in this study, strain CX-624T represents a novel species belonging to a novel genus of the Weeksellaceae, for which the name Marnyiella aurantia gen. nov., sp. nov. is proposed. The type strain is CX-624T (=GDMCC 1.1714T = JCM 33925T).