Sneathiella chinensis gen. nov., sp. nov., a novel marine alphaproteobacterium isolated from coastal sediment in Qingdao, China

Abstract

The taxonomic position of strain LMG 23452T, which was isolated from coastal sediment from an aquaculture site near Qingdao, China, in 2000, was determined. Strain LMG 23452T comprised Gram-negative, non-spore-forming, motile rods and was found to be a halotolerant, aerobic, chemoheterotroph that produces catalase and oxidase. Comparative 16S rRNA gene sequence analysis revealed that strain LMG 23452T shared approximately 89 % sequence similarity with members of the genera Devosia, Hyphomonas, Ensifer and Chelatococcus, which belong to two different orders within the Alphaproteobacteria. Further phylogenetic analysis of the 16S rRNA gene sequence showed that strain LMG 23452T formed a separate branch within the order Rhizobiales, falling between the genera Devosia and Ensifer of the families Hyphomicrobiaceae and Rhizobiaceae, respectively. Strain LMG 23452T could be differentiated from its closest phylogenetic neighbours on the basis of several phenotypic features, including hydrolysis of the substrates starch and casein and assimilation of the carbohydrates d-glucose, d-mannose, mannitol, maltose and l-arabinose, and chemotaxonomically by the presence of the fatty acids C14 : 0 3-OH, C16 : 1 ω11c, C16 : 1 ω5c and C18 : 1 ω5c. The major fatty acids detected in strain LMG 23452T were C18 : 1 ω7c, C16 : 0, C19 : 0 cyclo ω8c, C16 : 1 ω7c and C17 : 1 ω6c and the G+C content of the genomic DNA was 57.1 mol%. Therefore, the polyphasic data support the placement of strain LMG 23452T within a novel genus and species, for which the name Sneathiella chinensis gen. nov., sp. nov. is proposed. The type strain is LMG 23452T (=CBMAI 737T).