Flavihumibacter stibioxidans sp nov., an antimony-oxidizing bacterium isolated from antimony mine soil

A Gram-stain-positive, strictly aerobic, non-motile and rod-shaped bacterial strain, designated YS-17(T), was isolated from soil in the Lengshuijiang antimony mine, Hunan Province, China. Comparative 16S rRNA gene sequencing analysis clustered it with Flavihumibacter strains, and strain YS-17(T) was most closely related to Flavihumibacter cheonanensis WS16(T) (97.2% similarity), Flavihumibacter petaseus T41(T) (96.6 %) and Flavihumibacter solisilvae 3-3 T (96.5 %). The level of DNA-DNA relatedness between strain YS-17(T) and F. cheonanensis JCM 19322(T) was 35.5 +/- 0.1% (n= 2). The major respiratory quinone of strain YS-17 T was menaquinone-7 and the major polar lipids were phosphatidylethanolamine, two unidentified lipids, two unidentified amino lipids and phospholipid. The major fatty acids (>= 5 %) were iso-C-15 : 0, iso-C-15 : 1 G, unknown ECL 13.565, iso-C-17 : 0 3-OH, C-15 : 0, C-16 : 1 omega 5c and anteiso-C-15 : 0. The DNA G+C content was 47.8 mol%. Compared with other Flavihumibacter strains, strain YS-17(T) showed major biophysical and biochemical differences, with the ability to hydrolyse gelatin and to assimilate salicin and L-proline. The results demonstrated that strain YS-17(T) belongs to the genus Flavihumibacter and represents a novel species, for which the name Flavihumibacter stibioxidans sp. nov. is proposed. The type strain is YS-17(T) (=CCTCC AB 2016053(T) = KCTC 52205(T)).