Erythrobacter spongiae sp. nov., isolated from marine sponge

Abstract

A taxonomic study was carried out on strain HN-E23(T), which was isolated from sponge collected from Yangpu Bay, Hainan, China. Cells of strain HN-E23(T) were Gram-stain-negative, non-motile, orange-yellow-pigmented, short rods, that could grow at 10-40 degrees C (optimum, 28 degrees C), at pH 5-11 (optimun, pH 7) and in 0.5-12 % (w/v) NaCl (optimum, 3 %). This isolate was positive for oxidase, catalase, and the hydrolysis of aesculin, but negative for indole production and the reduction of nitrate. The phylogenetic tree based on 16S rRNA gene sequences revealed that strain HN-E23(T) formed a distinct phylogenetic lineage within the cluster comprising Erythrobacter strains. Strain HN-E23(T) shared the highest 16S rRNA gene sequence similarity to Erythrobacter aquimixticola JSSK-14(T) (97.2 %), followed by Erythrobacter atlanticus s21-N3(T) (96.6 %), Erythrobacter luteus KA37(T) (96.5 %) and Erythrobacter citreus RE35F/1(T) (96.4 %). The digital DNA-DNA hybridization (dDDH) and the average nucleotide identity (ANI) values between strain HN-E23(T) and JSSK-14(T) were 18.8 and 74.9 %, respectively. The dDDH and ANI values are below the standard cut-off criteria for delineation of bacterial species. The dominant fatty acids were summed feature 8 (C-18:1 omega 7c/omega 6c), C-16:0 and summed feature 3 (C-16:1 omega 7c/omega 6c). The major polar lipids comprised phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, sphingoglycolipid, an unidentified glycolipid and six unidentified lipids. The respiratory lipoquinone was identified as Q-10. The G+C content of the genomic DNA was 65.5 mol%. Based on the phenotypic and phylogenetic data, strain HN-E23(T) represents a novel species of the genus Erythrobacter, for which the name Erythrobacter spongiae sp. nov. is proposed, with the type strain HN-E23(T)(=MCCC 1K03331(T)=LMG 30457(T)).