A Gram-stain-negative, strictly aerobic, cream yellow colored, non-motile, rod-shaped bacterial strain, designated MAH-1T was isolated from rhizospheric soil of Coriandrum sativum. A polyphasic taxonomic study was performed on the isolated strain. Optimal growth occurred at 28-30 °C, pH 6.5 and 0% NaCl. The strain showed activity for both catalase and oxidase tests. Cell growth occurs on R2A agar, nutrient agar and Luria-Bertani agar. Cells were able to hydrolyze starch, aesculin, gelatin, and Tween 20. Alignment of 16S rRNA gene sequences indicated that strain MAH-1T was associated with the genus Flavobacterium and was most closely related to Flavobacterium longum YIT 12745T (94.5% sequence similarity) and Flavobacterium caeni LM5T (93.0%). Strain MAH-1T had a genome size of 3,975,600 bp. Genome contained 67 contigs encoded by 3,522 protein-coding genes with 38 tRNA and 6 rRNA genes. The genomic DNA G + C contents of strain MAH-1T was 47.1 mol %. The genomic ANI and dDDH values between strain MAH-1T and one of the close relatives F. caeni LM5T were 72.2 and 18.8%, respectively. The major fatty acids were C15:0 iso, C16:0 iso and C15:0 anteiso. The predominant respiratory quinone was menaquinone 6 (MK-6). Based on physiological, biochemical and phylogenetic data for this isolate, it was confirmed that strain MAH-1T was affiliated to the genus Flavobacterium and represented a novel species, for which the name Flavobacterium agri sp. nov. is proposed. The type strain is MAH-1T (= KACC 19300T = CGMCC 1.16617T).
Keywords: Flavobacterium agri; Genome sequence; Gram-staining negative; Menaquinone 6.