In this study, cry genes were amplified by cry4 gene primers from the isolates of Bt-23, Bt-133, Bt-190, and Bt-242 and sequences was carried out. Different computer algorithms were used to analyze the nucleotide sequences obtained from the isolates Bt-23, Bt-133, Bt-190 and Bt-242. Homology search of nucleotide sequences obtained from isolates Bt-23, Bt-133, Bt-190, and Bt-242 with showed homology with cry4A, cry4D, cry4BLB and other dipteran specific insecticidal genes, There were five open reading frames in Bt-23cry4, with the longest one located on +3 strand starting from base 279 to 683, having a length of 405 bases. The A+T and G+C base pair composition was 60.6 per cent and 39.4 per cent in Bt-23cry4, while Bt-133cry4 A+T was 61 per cent and G+C was 38.8 per cent. Bt-190cry4 was comparatively rich in A+T (64.3%) among all sequences with very low G+C (35.7%). In contrast, Bt-242cry4 was comparatively low in A+T content (57.2%) than the other gene sequences.
Bacillus thuringiensis, cry4 gene, nucleotide sequences, Open reading frame
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