Actirhodobacter atriluteus gen. nov., sp. nov., isolated from the surface water of the Yellow Sea

Abstract

A Gram-stain-negative, aerobic, orange-pigmented bacterial strain, designated HHU K3-1T, was isolated from the surface water of the Yellow Sea. The strain was observed to grow on 2216E agar medium, and growth occurred at pH 6.0-8.0 (optimum 7.0), 28-37 °C (optimum 28°C), and in the presence of 0.5-5% (w/v) NaCl (optimum 1-3%). The major fatty acids (> 10%) were summed feature 3 (C16:1ω6c/C16:1ω7c), C17:1ω6c and summed feature 8 (C18:1ω6c/C18:1ω7c). Strain HHU K3-1T was found to contain ubiquinone-10 as the predominant quinone and the major polar lipids were diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), phosphatidylglycerol (PG) and sphingoglycolipid (SGL). The 16S rRNA gene sequence analysis indicated that strain HHU K3-1T shared highest similarities with Pelagerythrobacter marensis KCTC 22370T (97.7%) and Qipengyuania oceanensis MCCC 1A09965T (96.9%). However, a phylogenetic tree based on 288 orthologous clusters (OCs) indicated that HHU K3-1T was close related to Parapontixanthobacter aurantiacus MCCC 1A09962T. The pairwise AAI and evolutionary distance between HHU K3-1T and Parapontixanthobacter aurantiacus MCCC 1A09962T are 67.1% and 0.43, respectively, which meet the recently proposed standard to differentiate genera in the family Erythrobacteraceae. On the basis of the result obtained by the polyphasic taxonomic study, strain HHU K3-1T can be considered to represent a novel genus in the family Erythrobacteraceae, for which the name Actirhodobacter atriluteus gen. nov., sp. nov. is proposed. The type strain is HHU K3-1T (= MCCC 1K04225T = KCTC 72834T = CGMCC 1.17395T).