Idiomarina aquatica sp nov., a moderately halophilic bacterium isolated from salterns

Four bacterial strains, SN-14(T), SN-4, M6-46 and M6-58B, were isolated from water of ponds of two salterns located in Huelva (Spain). They were Gram-stain-negative, aerobic and slightly curved rods. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the four strains belong to the genus Idiomarina, being related most closely to Idiomarina fontislapidosi F23(T) (98.4-98.0% sequence similarity), Idiomarina seosinensis CL-Sp19(T) (98.3-98.0%), Idiomarina piscisalsi TPS4-2(T) (97.9-97.4%), Idiomarina baltica OS145(T) (97.5-97.4%) and Idiomarina zobellii KMM 231(T) (97.6-97.0%). The level of similarity with the type species of the genus, Idiomarina abyssalis KMM 227(T), was 97.2-96.7%. The novel strains exhibited optimal growth at 5-10% (w/v) total salts, pH 7 and 37 degrees C. The major fatty acids of strain SN-14(T) were iso-C-15 : 0, iso-C-17 : 0, C-18 :1 omega 7c/C-18 : 1 omega 6c, C-16: 0 and iso-C-17 : 1 omega 9C/C-16 : 0 10-methyl. The DNA G+C content range was 47.6-50.8 mol%. The level of DNA DNA relatedness between strain SN-14(T) and I. fontislapidosi F23(T) was 13%, while those between strain SN-14(T) and the other three new isolates were between 77 and 99%. These data demonstrated that the four isolates constitute a novel species of the genus Idiomarina. Based on the phylogenetic, genotypic, phenotypic and chemotaxonomic data, the four strains represent a novel species of the genus Idiomarina, for which the name Idiomarina aquatica sp. nov. is proposed. The type strain is SN-14(T) (=CCM 8471(T)=CECT 8360(T)=LMG 27613(T)).