Salipaludibacillus halalkaliphilus sp. nov., a moderately haloalkaliphilic bacterium from a coastal-marine wetland.

Abstract

A Gram-stain-positive, endospore-forming rod-shaped non-motile, moderately halophilic and alkaliphilic bacterium, strain GASy1T, was isolated from a water sample from Gomishan, a marine wetland in Iran. GASy1T required at least 0.5 % (w/v) NaCl for growth and was able to grow at NaCl concentrations of up to 15 % (w/v), with optimum growth occurring at 5 % (w/v) NaCl. The optimum pH and temperature for growth were pH 8.5-9.0 and 30 °C, respectively, while it was able to grow over a pH range and a temperature range of 7.5-10.0 and 4-40 °C, respectively. GASy1T was catalase-positive and oxidase-negative. Analysis of 16S rRNA gene sequences revealed that GASy1T represents a member of the genus Salipaludibacillus, family Bacillaceae within the order Bacillales, showing 97.4 % sequence similarity to Salipaludibacillus neizhouensis JSM 071004T, and 96.2 and 95.7 % sequence similarity to Salipaludibacillus agaradhaerens AC 13T and Salipaludibacillus aurantiacus S9T, respectively. The DNA G+C content of GASy1T was 38.8 mol%. The polar lipids of the strain were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and two unidentified phospholipids and its major cellular fatty acids were anteiso-C15 : 0, C16 : 0 and iso-C15 : 0. The isoprenoid quinone was MK-7. DNA-DNA hybridization experiments revealed a low level of relatedness between GASy1T and Salipaludibacillus neizhouensis IBRC-M 10892T (18 %). On the basis of a combination of phenotypic, chemotaxonomic and phylogenetic features, GASy1T represents a novel species of the genus Salipaludibacillus, for which the name Salipaludibacillus halalkaliphilus sp. nov. is proposed. The type strain of Salipaludibacillus halalkaliphilus is GASy1T (=IBRC M 10902T=LMG 28385T).