DIVERSITY OF BACILLUS GENOTYPES IN SOIL SAMPLES FROM EL-OMAYED BIOSPHERE RESERVE IN EGYPT

Abstract

Sequencing of the 16S rDNA hypervariant region was applied to determine the presence and composition of Bacillus species in 40 soil samples randomly collected from different habitats in El-Omayed biosphere reserve, Egypt. Although purified cultures showed 18 different phenotypes that were morphologically distinct on a sporulation medium plate, only 4 different nucleotide sequences designated Seq A, B, C and D were revealed. Computational analysis of DNA sequence data suggested that 17 of these isolates are closely related members of the Bacillus cereus/thuringiensis group (Seq B, C and D) and one isolate is belonging to the Bacillus subtilis group (Seq A). Further phenotypic investigations confirmed the diversity of the 17 novel Bacillus cereus/thuringiensis isolates and indicated that the new Bacillus subtilis group isolate is a Bacillus amyloliquefaciens strain. A simple phenotypic discrimination key that can be applied for distinguishing between such closely related Bacillus cereus/thuringiensis members is presented