Marinococcus tarijensis sp. nov., a moderately halophilic bacterium isolated from a salt mine

Abstract

A Gram-stain-positive, coccoid-shaped, halophilic bacterium, strain SR-1(T), was isolated from a salt crystal obtained from a mine located in Tarija, Bolivia. The strain was investigated using a polyphasic approach. The optimum conditions for growth of strain SR-1(T) were reached at 5% (w/v) NaCl, pH 7.6 and 37-40 °C. The peptidoglycan contained meso-diaminopimelic acid as the diagnostic diamino acid. The isoprenoid quinone was MK-7. The major cellular fatty acids of strain SR-1(T) were anteiso-C(15:0), anteiso-C(17:0) and iso-C(16:0). The DNA G+C content of strain SR-1(T) was 48.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed a close relationship between strain SR-1(T) and Marinococcus halophilus JCM 2479(T) (99.7% 16S rRNA gene sequence similarity), Marinococcus halotolerans KCTC 19045(T) (99.4%) and Marinococcus luteus KCTC 13214(T) (99.8%). However, strain SR-1(T) also showed low levels of DNA-DNA relatedness with these reference strains (47, 61 and 58%, respectively). On the basis of phenotypic differences and DNA-DNA hybridization results, strain SR-1(T) is considered to represent a novel species of the genus Marinococcus, for which the name Marinococcus tarijensis sp. nov. is proposed. The type strain is SR-1(T) ( =LMG 26930(T) =CECT 8130(T)).