Agricultural and Biological Research

Molecular Characterization of Bacillus thuringiensis strains from Soil Sample in North Gondar, Ethiopia

Molaligne Medfu Tarekegn* and Fikirte Zewdu Salillih

Bacillus thuringiensis (Bt.), gram-positive, spore-forming bacteria, is pervasive and can be found in all kinds of natural environments. Several methods have been used to isolate and characterize Bt. for this investigation. Fourteen Bt. in North Gondar, Ethiopia, isolates were found in eight different soils. Bt. the physical properties of the colonies, the structure of the parasporal crystals, and the PCR-amplification profiles were used for identifying. For both sets of primers, including those for the cry1 and cry9 genes, 12 strains demonstrated successful results. 50 Bt. strains were found among the 72 bacterial strains that were examined to have 4 different forms of crystalline inclusions. The majority of the 15 isolates (30%) had irregular pointed Bt. crystals, while 20, 24, and 26% of the strains had bi-pyramidal, cuboidal, and spherical crystals, respectively. According to the PCR results, 50% of isolates amplifying the cry 9 gene and the cry1 gene (35.71%), indicating that the cry 9 gene frequency predominated. Two strains did not amplify. Bt. variety was evaluated using a combination examination of their protein and PCR banding patterns. This study reveals that the distribution of Cry-type genes can be used to classify and identify Bt. isolates that were recovered from soil samples in the North Gondar Zone.