Aliidiomarina sedimenti sp. nov., a haloalkaliphilic bacterium in the family Idiomarinaceae

A novel Gram-staining-negative straight or curved rod-shaped, moderately halophilic and alkaliphilic bacterium, designated strain GBSy1T, was isolated from a sediment sample from the coastal-marine wetland Gomishan in Iran. GBSy1T was motile, and formed non-pigmented, mucoid colonies. Growth occurred with between 1 and 15 % (w/v) NaCl and the isolate grew optimally with 5 % (w/v) NaCl. The optimum pH and temperature for growth were 8.5 and 34 °C, while the strain was able to grow at pH 7.0-10 and 4-40 °C. On the basis of the results of 16S rRNA gene sequence analysis, GBSy1T was shown to represent a member of the genus Aliidiomarina within the class Gammaproteobacteria, family Idiomarinaceae and showed closest phylogenetic similarity to Aliidiomarina marisCF12-14T (97.7 %). The DNA G+C content of GBSy1T was 51.2 mol%. The cells of GBSy1T contained the isoprenoid ubiquinones Q-8, Q-9 and Q-10 (92, 2 and 2 %, respectively). The major cellular fatty acids of the isolate were iso-C11 : 0 3-OH, iso-C15 : 0, iso-C17 : 0 and iso-C17 : 1ω9c and its polar lipid profile comprised phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and three unknown phospholipids. The level of DNA-DNA relatedness between GBSy1T and Aliidiomarina marisDSM 22154T was 31 %. All these features confirmed the placement of GBSy1T within the genus Aliidiomarina. On the basis of evidence from this study, a novel species of the genus Aliidiomarina, Aliidiomarina sedimenti sp. nov., is proposed, with GBSy1T (=IBRC-M 10764T=CECT 8340T) as the type strain.