Ruegeria arenilitoris sp. nov., isolated from the seashore sand around a seaweed farm

Abstract

A Gram-negative, motile and rod-shaped bacterial strain, G-M8(T), which was isolated from seashore sand around a seaweed farm at Geoje island in South Korea, was characterized taxonomically. It grew optimally at 30-37°C, at pH 7.0-8.0 and in presence of 2% (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain G-M8(T) joined the cluster comprising the type strains of Ruegeria atlantica and Ruegeria lacuscaerulensis, showing 97.5% sequence similarity, by a bootstrap resampling value of 85.8%. It exhibited 16S rRNA gene sequence similarity values of 95.4-96.7% to the type strains of the other Ruegeria species. Strain G-M8(T) exhibited the highest gyrB sequence similarity value (88.5%) to the type strain of R. lacuscaerulensis. Strain G-M8(T) contained Q-10 as the predominant ubiquinone and C(18:1) ω7c as the predominant fatty acid. The polar lipid profile of strain G-M8(T) was similar to that of R. atlantica KCTC 12424(T). The DNA G+C content of strain G-M8(T) was 64.6mol% and its mean DNA-DNA relatedness values with R. atlantica KCTC 12424(T) and R. lacuscaerulensis KCTC 2953(T) were 18±5.3 and 10±3.6%, respectively. Differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, demonstrated that strain G-M8(T) is distinguished from other Ruegeria species. On the basis of the data presented, strain G-M8(T) (=KCTC 23960(T)=CCUG 62412(T)) represents a novel species of the genus Ruegeria, for which the name Ruegeria arenilitoris sp. nov. is proposed.