Aurantiacibacter rhizosphaerae sp. nov., isolated from a rhizosphere mudflat of a halophyte and proposal to reclassify Erythrobacter suaedae Lee et al. 2019. and Erythrobacter flavus Yoon et al. 2003 as Aurantiacibacter suaedae comb. nov. and Qipengyuania flava comb. nov., respectively
Soon Dong Lee, In Seop Kim
Abstract
A marine alphaproteobacterium, designated as strain GH3-10 T , was isolated from the rhizosphere mud of a halophyte ( Suaeda japonica ) collected at the seashore of Gangwha Island, Republic of Korea. The isolate was found to be Gram-stain-negative, strictly aerobic, catalase- and oxidase-positive, non-motile, short rods and produced orange-coloured colonies. The 16S rRNA gene- and whole genome-based phylogenetic analyses exhibited that strain GH3-10 T belonged to the genus Aurantiacibacter and was most closely related to Aurantiacibacter atlanticus s21-N3 T (98.7 % 16S rRNA gene sequence similarity) and Aurantiacibacter marinus KCTC 23554 T (98.4 %). The major respiratory quinone was ubiquinone-10. The polar lipids consisted of phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, sphingoglycolipid and an unidentified lipid. The major fatty acids were C 18 : 1 ω 7 c , summed feature 3 (C 16 : 1 ω 7 c and/or C 16 : 1 ω 6 c ) and C 18 : 1 ω 7 c 10-methyl. The DNA G+C content was 61.3 mol% (by genome). Average nucleotide identity and DNA–DNA relatedness values between the isolate and its phylogenetically closest relatives, together with phenotypic distinctness warranted the taxonomic description of a new species. On the basis of data obtained by a polyphasic approach, strain GH3-10 T (=KCTC 62379 T =JCM 32444 T ) represents a novel species of the genus Aurantiacibacter , for which the name Aurantiacibacter rhizosphaerae sp. nov. is proposed. According to phylogenetic coherence based on 16S rRNA genes and core genomes, it is also proposed that Erythrobacter suaedae Lee et al . 2019. and Erythrobacter flavus Yoon et al . 2003 be transferred to Aurantiacibacter suaedae comb. nov. and Qipengyuania flava comb. nov., respectively.