Piscibacillus Halophilus Sp Nov., A Moderately Halophilic Bacterium From A Hypersaline Iranian Lake

A Gram-positive, moderately halophilic bacterium, designated strain HS224(T), was isolated from the hypersaline lake Howz-Soltan in Iran. Cells of strain HS224(T) were rod-shaped, motile and produced oval endospores. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain HS224(T) was affiliated to the genus Piscibacillus, exhibiting 98.5% sequence similarity to the type strain of Piscibacillus salipiscarius. Strain HS224(T) was also related closely to the type strains of Aquisalibacillus elongatus (98.0% 16S rRNA gene sequence similarity), Filobacillus milosensis (97.9%) and Tenuibacillus multivorans (97.0%). Strain HS224(T) was able to grow at NaCl concentrations of 1-20% (w/v), with optimum growth occurring at 10% (w/v) NaCl. The optimum temperature and pH for growth were 35 degrees C and pH 7.5. Major polar lipids were phosphatidylglycerol and diphosphatidylglycerol, the isoprenoid quinone was MK-7 and the peptidoglycan type was A1 gamma, with meso-diaminopimelic acid as the diagnostic diamino acid; these characteristics were shared with P. salipiscarius. The major cellular fatty acids of strain HS224(T) were anteiso-C(15:0), iso-C(15:0), anteiso-C(17:0) and iso-C(16:0). The G + C content of the DNA was 37.5 mol%. The level of DNA-DNA relatedness between strain HS224(T) and P salipiscarius JCM 13188(T) was 30.8%. It is evident from the genotypic, chemotaxonomic and phenotypic data presented that strain HS224(T) represents a novel species of the genus Piscibacillus, for which the name Piscibacillus halophilus sp. nov. is proposed. The type strain is HS224(T) (= CCM 7596(T) = DSM 21633(T) = JCM 15721(T) = LMG 24786(T)).