Filimonas effusa sp. Nov., isolated from a freshwater river

Abstract

Strain TTM-71T, isolated from a freshwater river in Taiwan, was characterized using a polyphasic taxonomic approach. Phylogenetic analyses based on 16S rRNA gene sequences and an up-to-date bacterial core gene set (92 protein clusters) indicated that strain TTM-71T is affiliated with species in the genus Filimonas. The 16S rRNA gene sequence similarity indicated that strain TTM-71T is closely related to species within the genus Filimonas (94.7–95.5% sequence similarity) and had a high sequence similarity with Filimonas endophytica SR 2-06T (95.5 %). Strain TTM-71T showed 70.3% average nucleotide identity and 24.9% digital DNA–DNA hybridization identity with Filimonas lacunae YT21T. Cells were Gram-stain-negative, aerobic, motile by gliding, rod-shaped and formed beige-colored colonies. Optimal growth occurred at 20 °C, pH 8, and in the presence of 0.5% NaCl. The major fatty acids of strain TTM-71T were iso-C15:0, iso-C15:1 G and summed feature 3 (comprising C16:1 ω7c and/or C16:1 ω6c). The predominant hydroxy fatty acid was iso-C17:0 3-OH. The polar lipid profile consisted of a mixture of phosphatidy-lethanolamine, four uncharacterized aminophospholipids, one uncharacterized aminolipid, one uncharacterized phospholipid and one uncharacterized lipid. The predominant polyamine was homospermidine. The only isoprenoid quinone was MK-7. Genomic DNA G+C content was 45.6 mol%. On the basis of the polyphasic evidence presented, strain TTM-71T is considered to represent a novel species of the genus Filimonas, for which the name Filimonas effusa sp. nov. is proposed. The type strain is TTM-71T (=BCRC 81160T=LMG 31017T=KCTC 62871T).