Flavobacterium arundinis sp. nov., Flavobacterium calami sp. nov., Flavobacterium helocola sp. nov. and Flavobacterium flavipallidum sp. nov., isolated from stagnant water in a clump of Phragmites japonica Steud

Abstract

Four novel bacterial strains were isolated from stagnant water in a clump of Phragmites japonica Steud. The four Gram-negative, facultatively anaerobic, rod-shaped, non-motile and yellow-coloured strains were designated as DGU11T, DGU38T, DGU41T and DGU99T. The four novel strains exhibited 16S rRNA gene similarities with their closest type strains, ranging from 95.7 to 98.7%, average nucleotide identity values from 75.3 to 95.6% and digital DNA–DNA hybridization values between 17.9 and 59.6%. The cells of strain DGU11T were non-motile and grew at 10−30°C (optimum 25 °C), a pH range of 4.0–12.0 (optimum 9.0) and in the presence of 0–1.0% sodium chloride (NaCl) (optimum 0%). The cells of strain DGU38T were non-motile and grew at 10−35°C (optimum 30 °C), a pH range of 4.0–8.0 (optimum 7.0) and at 0 –2.0% NaCl (optimum 0%). The cells of strain DGU41T were non-motile and grew at 15−50°C (optimum 30 °C), a pH range of 6.0–9.0 (optimum 7.0) and in the presence of 0% NaCl (optimum 0%). The cells of strain DGU99T were non-motile and grew at 15−35°C (optimum 25 °C), a pH range of 6.0–12.0 (optimum 9.0) and in the presence of 0 –2.0% NaCl (optimum 0%). The major fatty acid composition of the four novel strains was iso-C15:0 and C16:1 ω7c/C16:1 ω6c, which is similar to other Flavobacterium species. The proposed names of the novel strains are Flavobacterium arundinis sp. nov. (type strain DGU11T =KACC 23722T =TBRC 19004T), Flavo-bacterium calami sp. nov. (type strain DGU38T =KACC 23723T =TBRC 19005T), Flavobacterium helocola sp. nov. (type strain DGU41T =KACC 23724T =TBRC 19006T) and Flavobacterium flavipallidum sp. nov. (type strain DGU99T =KACC 23725T =TBRC 19007T). © 2025 The Authors.