Halomonas urmiana sp. nov., a moderately halophilic bacterium isolated from Urmia Lake in Iran

Abstract

In the course of screening halophilic bacteria in Urmia Lake in Iran, which is being threatened by dryness, a novel Gram-negative, moderately halophilic, heterotrophic and short rod-shaped bacteria was isolated and characterized. The bacterium was isolated from a water specimen and designated as TBZ3T. Colonies were found to be creamy yellow, with catalase- and oxidase-positive activities. The growth of strain TBZ3T was observed to be at 10–45 °C (optimum, 30 °C), at pH 6.0–9.0 (optimum, pH 7.0) and in the presence of 0.5–20 % (w/v) NaCl (optimum, 7.5 %). Strain TBZ3T contained C16 : 0, cyclo-C19 : 0  ω8c, summed feature 3 (comprising C16 : 1  ω7c and/or C16 : 1  ω6c) and summed feature 8 (comprising C18 : 1  ω7c and/or C18 : 1  ω6c) as major fatty acids and ubiquinone-9 as the only respiratory isoprenoid quinone. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, glycolipid, unidentified phospholipid and unidentified polar lipids were detected as the major polar lipids. Strain TBZ3T was found to be most closely related to Halomonas saccharevitans AJ275T , Halomonas denitrificans M29T and Halomonas sediminicola CPS11T with the 16S rRNA gene sequence similarities of 98.93, 98.15 and 97.60 % respectively and in phylogenetic analysis strain TBZ3T grouped with Halomonas saccharevitans AJ275T contained within a large cluster within the genus Halomonas . Based on phenotypic, chemotaxonomic and molecular properties, strain TBZ3T represents a novel species of the Halomonas genus, for which the name Halomonas urmiana sp. nov. is proposed. The type strain is TBZ3T (=DSM 22871T=LMG 25416T).