Arcobacter pacificus sp. nov., isolated from seawater of the South Pacific Gyre.

A Gram-stain-negative, rod-shaped, slightly curved, non-spore-forming strain, designated SW028T, was isolated from surface seawater (26° 29' S 137° 56' W) of the South Pacific Gyre during the Integrated Ocean Drilling Program Expedition 329. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SW028T belonged to the genus Arcobacter and it showed the highest sequence similarity with Arcobacter molluscorum LMG 25693T (95.50 %). The dominant fatty acids of strain SW028T were C18 : 1ω7c, C16 : 1ω7c and C16 : 0. The only respiratory quinone detected was menaquinone-6. The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine and an unidentified phospholipid. The DNA G+C content was 27.1 mol%. The phylogenetic position of the novel strain was further confirmed by analysis of the housekeeping genes rpoB, gyrB and atpA. On the basis of phenotypic, chemotaxonomic and phylogenetic analyses, strain SW028T represents a novel species of the genus Arcobacter, for which the name Arcobacter pacificus is proposed. The type strain is SW028T ( = DSM 25018T = JCM 17857T = LMG 26638T = CGMCC NO.1.11011T).