Phenotypic and Genotypic Characterization of Three Novel Halophilic Bacillus Strains from Jordanian Hot Springs

Three strains of facultatively anaerobic thermotolerant and moderately halophilic bacteria were isolated from two Jordanian hot spring locations. The novel Bacillus strains were short rods, Gram-positive, motile and spore formers. The strains were capable of anaerobic (but not aerobic) growth at 63 °C, moderately halophilic, able to grow at NaCl concentration range of 12-15 % and at temperatures range of 37-63 °C. Moreover, the strains were resistant to aztreonam, bacitracin and oxacillin. The range of the guanine-plus-cytosine content of the strain s DNAs was 43 – 54 mol%. The three strains HAR7100^T, HAR720^T and HAR200^T, differ phenotypically from each other in terms of antibiotic resistance, compositions of polar lipids, presence and absence of several enzyme activities such as amylase, protease alkaline phosphatase, G6PDH and 6PGDH. Moreover, the novel Bacillus strains were shown to differ genotypically by random amplified polymorphic DNA fingerprinting and 16S rDNA amplification patterns. Phenotypic and genotypic variations may support establishment of new strains of the same genus Paenibacillus.