Detection of cryIII gene in Local Isolate of Bacillus thuringiensis Using Polymerase Chain Reaction (PCR)

Bacillus thuringiensis is a biological biopesticide that was used for defense against pests. In B. thuringiensis there is a Cry protein that is only toxic to certain insects. This Cry protein is encoded by cry gene. There are many types of cry genes that have been identified, one of which is cryIII gene that is toxic to insects from the Coleoptera group as pests in sweet potato (Ipomoea batatas). The aim of this study was to amplify the cryIII gene from local isolate of B. thuringiensis. The method that can be used for cryIII gene amplification is Polymerase Chain Reaction (PCR). The primer pair is one of the important factors that determine the success of PCR. From a number of designed primers, the primer pair selected to be used in this study is Cry3B forward 5'-AAAGTGCGGCTATTCGACCA-3' and Cry3B reverse 5'-CACTTCATCCTGTGACG CCT-3'. This primer pair successfully amplified cryIII gene and showed a DNA band with molecular size approximately 914 base pairs. Gradient PCR needs to be done for optimizing specific amplification of cryIII gene.