Flexivirga aerilata sp. nov., Isolated from an Automobile Air Conditioning System


A novel light-yellow-coloured, Gram-stain-positive, nearly-coccoid, aerobic bacterium, designated strain ID2601ST was isolated from a car evaporator core collected from South Korea. Strain ID2601ST was catalase positive and oxidase negative, able to grow at pH 6.0–8.0, temperature 20–45 °C, and 0–6.0% (w/v) NaCl concentration. The 16S rRNA gene sequence analysis showed that strain ID2601ST belonged to the genus Flexivirga, with the nearest phylogenetic neighbour being Flexivirga endophytica YIM 7505T (97.9% sequence similarity). The strain comprised diphosphatidylglycerol as the main polar lipid; MK-8(H4) as a predominant respiratory quinone; serine, alanine, glycine, glutamic acid, and lysine as main components of peptidoglycan and iso-C16:0, summed feature 9 (iso-C17:1ω9c and/or C16:0 10-methyl), anteiso-C17:0, and C17:0 10-methyl as the major fatty acids. The average nucleotide identity (ANI) values between strain ID2601ST and the closest species (Flexivirga endophytica YIM 7505T and Flexivirga caeni BO-16T) were < 78%. The in silico DNA–DNA hybridization (dDDH) values of strain ID2601ST with the closest species were < 22%. These observations were below the threshold values of 95% (for ANI) and 70% (for dDDH) used for species delineation. The DNA G+C content was 69.8 mol%. Based on the polyphasic taxonomic data, the novel species Flexivirga aerilata sp. nov. is proposed with the type strain ID2601ST (=KCTC 49353T =NBRC 114622T).

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This research was supported by Sangji University Research Fund, 2020 and grant from the National Institute of Biological Resources (NIBR), funded by the Ministry of Environment (MOE) of the Republic of Korea (NIBR202002108).

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Chaudhary, D.K., Lee, H., Dahal, R.H. et al. Flexivirga aerilata sp. nov., Isolated from an Automobile Air Conditioning System. Curr Microbiol 78, 796–802 (2021). https://doi.org/10.1007/s00284-020-02300-z

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