Abstract
A novel bacterium, designated strain 2305UL40-4(T), was isolated from Cellana toreuma (a Korean limpet) collected from Ulleung Island, Republic of Korea. The cells were Gram-stain-negative, aerobic, rod-shaped (0.5-0.9 µm×1.5-2.2 µm) and non-motile. Growth was observed at 22-36 °C (optimum 25-30 °C), pH 6-8 (optimum pH 7) and in the presence of 0.5-4.0% (w/v, optimum 2.0%) NaCl. The 16S rRNA gene sequence analysis revealed that strain 2305UL40-4(T) shared 97.4% similarity with Aestuariibius insulae DBTF-13(T). The average nucleotide identity value between the two strains was 76.5%, and the digital DNA-DNA hybridization value was 19.0%. Both values are well below the species delineation thresholds. The DNA G+C content of strain 2305UL40-4(T) was 63.8 mol%. The major fatty acids were C(16 : 0), C(18 : 0) and summed feature 8 (C(18 : 1) ω7c and/or C(18 : 1) ω6c). Major polar lipids included phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, five unidentified aminolipids and fifteen unidentified lipids. Ubiquinone-10 was the predominant quinone. The new strain differs from A. insulae in its ability to utilize d-raffinose, d-ribose and d-xylose. Based on these polyphasic taxonomic characteristics, strain 2305UL40-4(T) is proposed as a novel species within the genus Aestuariibius, with the name Aestuariibius violaceus sp. nov. The type strain is 2305UL40-4(T) (=KCCM 43505(T)=MCCC 1K09164(T)).