A Gram-stain-negative, rod-shaped bacterium, strain H23T, was isolated from farmland soil sampled in Enshi City, Hubei Province, PR China. The isolate grew optimally at 28-32 °C, pH 8.0 and with 0.5 % (w/v) NaCl. Based on the results of 16S rRNA gene sequence and phylogenetic analyses, strain H23T belonged to the genus Luteimonas with the highest degree of 16S rRNA gene sequence similarity to Luteimonas cucumeris Y4T (97.41 %). The DNA G+C content was 65.88 mol%. The average nucleotide identity and the Genome-to-Genome Distance Calculator results also showed low relatedness (below 95 and 70 %, respectively) between strain H23T and type strains in the genus Luteimonas. Ubiquinone-8 was the predominant quinone. The major fatty acids were iso-C15 : 0, iso-C16 : 0, iso-C17 : 0 and iso-C17 : 1 ω9c. Polar lipids were dominated by diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and unidentified phospholipids. Low digital DNA-DNA hybridization values, as well as physiological and biochemical differences, such as no casein hydrolysis, being catalase-negative, and tesing positive for cystine arylamidase, α-chymotrypsin and N-acetyl-β-glucosaminidase, could distinguish strain H23T from its closely related species. Strain H23T is considered to represent a novel species in the genus Luteimonas, for which the name Luteimonas gilva sp. nov. is proposed, with strain H23T (=CCTCC AB 2019255T=KCTC 72593T) as the type strain.
Keywords: Luteimonas gilva; farmland soil; novel bacterium.