Roseovarius nanhaiticus sp. nov., a member of the Roseobacter clade isolated from marine sediment

Abstract

An aerobic, Gram-staining-negative, rod or ovoid-shaped bacterial isolate, strain NH52JT, was isolated from a sandy sediment sample from the South China Sea. Strain NH52JTexhibited tumbling motility, formed beige or faint pink colonies, gave a positive reaction in tests for catalase and oxidase and required NaCl for growth. Optimal growth was observed at pH 7.8–9.3, at 30 °C and in the presence of 2.0–4.0 % (w/v) NaCl. The novel strain did not synthesize bacteriochlorophylla, and the DNA G+C content was 62 %. The major fatty acids were C18 : 1ω7c, C16 : 0and C18 : 1ω7c11-methyl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NH52JTwas affiliated to the genusRoseovariusof the classAlphaproteobacteria.Roseovarius pacificusandRoseovarius aestuariiwere the most closely related recognized species to strain NH52JTwith 16S rRNA gene sequence similarity values of 95.0 and 95.7 %, respectively. Sequence similarity values between strain NH52JTand other phylogenetically related species were all below 95.0 %. Based on the phenotypic, chemotaxonomic and phylogenetic data presented, strain NH52JTis considered to represent a novel species of the genusRoseovarius,for which the nameRoseovarius nanhaiticussp. nov. is proposed. The type strain is NH52JT(=LMG 24840T=CCTCC AB 208317T=MCCC 1A03543T).