Halobacillus karajensis sp. nov., a novel moderate halophile

Abstract

A moderately halophilic, gram-positive, spore-forming bacterium was isolated from surface saline soil of the Karaj region, Iran. The strain, designated MA-2T, was strictly aerobic with rod-shaped cells that occurred singly, in pairs or short chains. It contained L-Om-D-Asp-type peptidoglycan and the major respiratory lipoquinone was MK-7. It was non-motile and had an ellipsoidal endospore located centrally or subterminally. Growth occurred at 10-49 degrees C and in the pH range 6.0-9.6. Strain MA-2T grew at salinities of 1-24% (w/v) NaCl, showing optimal growth at 10% (w/v). The DNA G + C content was 41.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain MA-2T was associated with Bacillus rRNA group 1. The micro-organisms showing the closest phylogenetic relationship to strain MA-2T were Halobacillus litoralis and Halobacillus trueperi. On the basis of phenotypic and chemotaxonomic characteristics, 16S rRNA gene sequence analysis and DNA-DNA similarity data, it is proposed that strain MA-2T (= DSM 14948T = LMG 21515T) should be placed in the genus Halobacillus as the type strain of a novel species, Halobacillus karajensis sp. nov.