Shewanella dokdonensis sp. nov., isolated from seawater

Abstract

A novel bacterial strain, designated UDC329T, was isolated from a sample of seawater collected at Dong-do, on the coast of Dokdo Island, in the East Sea of the Republic of Korea. The Gram-staining-negative, motile, facultatively anaerobic, non-spore-forming rods of the strain developed into dark orange–yellow colonies. The strain grew optimally between 25 and 30 °C, with 1 % (w/v) NaCl and at pH 7. It grew in the absence of NaCl, but not with NaCl at >7 % (w/v). The predominant menaquinone was MK-7, the predominant ubiquinones were Q-7 and Q-8, and the major fatty acids were iso-C15 : 0 (33.52 %) and C17 : 1ω8c (11.73 %). The genomic DNA G+C content of strain UDC329T was 50.2 mol%. In phylogenetic analyses based on 16S rRNA and gyrB gene sequences, strain UDC329T was grouped with members of the genus Shewanella and appeared most closely related to Shewanella fodinae JC15T (97.9 % 16S rRNA gene sequence similarity), Shewanella indica KJW27T (95.0 %), Shewanella algae ATCC 51192T (94.8 %), Shewanella haliotis DW01T (94.5 %) and Shewanella chilikensis JC5T (93.9 %). The level of DNA–DNA relatedness between strain UDC329T and S. fodinae JC15T was, however, only 27.4 %. On the basis of phenotypic, genotypic and DNA–DNA relatedness data, strain UDC329T represents a novel species in the genus Shewanella , for which the name Shewanella dokdonensis sp. nov. is proposed. The type strain is UDC329T ( = KCTC 22898T = DSM 23626T).