Luteimonas chenhongjianii, a novel species isolated from rectal contents of Tibetan Plateau pika (Ochotona curzoniae)

Abstract

Two Gram-stain-negative, strictly aerobic, bright-yellow-pigmented and rod-shaped bacteria (strains 100069 and 100111^T) with a single polar flagellum were isolated from the rectal contents of plateau pika (Ochotona curzoniae). Based on the results of nearly full-length 16S rRNA gene sequence and phylogenetic analyses, strains 100069 and 100111^T belong to the genus Luteimonas, and are closest to Luteimonas rhizosphaerae 4-12^T (98.02 % similarity), Luteimonas aestuarii B9^T (97.8 %) and Luteimonas terrae THG-MD21^T (97.74 %). The DNA G+C contents of these two isolates were 68.30 mol% and 68.29 mol%, respectively. The highest average nucleotide identity (ANI) value between strain 100111^T and its closely related species was 83.34 %, well below the threshold of 95-96 %. The major cellular fatty acids were iso-C_{11 : 0}, iso-C_{15 : 0} and iso-C_{17 : 1} ω9. Polar lipid content was dominated by diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid and an unidentified lipid. Ubiquinone-8 (Q-8) was the predominant respiratory quinone. These two isolates grew optimally at 35-37 °C, pH 7.0-8.0 and with 1.0 % (w/v) NaCl. The results of ANI analysis and other characteristics obtained from our polyphasic study showed that strains 100069 and 100111^T represent a novel species in genus Luteimonas, for which the name Luteimonas chenhongjianii sp. nov. (type strain 100111^T=DSM 104077^T=CGMCC 1.16429^T) is proposed.

Keywords: ANI; Luteimonas; novel species; phylogenetic analysis.