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 NH52JT exhibited 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 bacteriochlorophyll a, and the DNA G+C content was 62 %. The major fatty acids were C18 : 1ω7c, C16 : 0 and C18 : 1ω7c 11-methyl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NH52JT was affiliated to the genus Roseovarius of the class Alphaproteobacteria. Roseovarius pacificus and Roseovarius aestuarii were the most closely related recognized species to strain NH52JT with 16S rRNA gene sequence similarity values of 95.0 and 95.7 %, respectively. Sequence similarity values between strain NH52J T and other phylogenetically related species were all below 95.0 %. Based on the phenotypic, chemotaxonomic and phylogenetic data presented, strain NH52JT is considered to represent a novel species of the genus Roseovarius, for which the name Roseovarius nanhaiticus sp. nov. is proposed. The type strain is NH52JT (=LMG 24840T=CCTCC AB 208317T=MCCC 1A03543T). © 2010 IUMS.