Pistricoccus aurantiacus gen. nov., sp nov., a moderately halophilic bacterium isolated from a shark

A novel Gram-stain negative, non-motile, moderately halophilic, facultatively anaerobic and spherical bacterium designated strain SS9(T) was isolated from the gill homogenate of a shark. Cells of SS9(T) were observed to be 0.8-1.2 mu m in diameter. The strain was found to grow optimally at 33 A degrees C, pH 7.0-8.0 and in the presence of 6.0 % (w/v) NaCl. On the basis of 16S rRNA gene phylogeny, strain SS9(T) can be affiliated with the family Halomonadaceae and is closely related to Chromohalobacter marismortui NBRC 103155(T) (95.6 % sequence similarity), Halomonas ilicicola SP8(T) (95.6 %) and Chromohalobacter salexigens DSM 3043(T) (95.5 %). Multilocus sequence analysis of strain SS9(T) using the housekeeping genes 16S rRNA, 23S rRNA, gyrB, rpoD and secA revealed the strain's distinct phylogenetic position, separate from other known genera of the family Halomonadaceae. Strain SS9(T) was found to contain ubiquinone-9 (Q-9) as the predominant ubiquinone and C-18:1 omega 7c, C-16:0 and summed feature 3 (C-16:1 omega 7c and/or iso-C-15:0 2-OH) as the major fatty acids. The major polar lipids of strain SS9(T) were identified as phosphatidylglycerol and phosphatidylethanolamine. The DNA G + C content of strain SS9(T) was determined to be 60.4 mol%. It is evident from phylogenetic, genotypic, phenotypic and chemotaxonomic results that strain SS9(T) represents a novel species in a new genus, for which the name Pistricoccus aurantiacus gen. nov., sp. nov. is proposed. The type strain is SS9(T) (=KCTC 42586(T) = MCCC 1H00111(T)).