Detection Of Group I And Group Ii Introns In A Mexican Bacillus Thuringiensis Collection

Group I and II introns are non-coding sequences able to excise themselves from precursor mRNA by self-splicing. Both groups are ribozymes and may also code Open Reading Frames (ORF) for enzymes involved in the homing process; the Homing Endonuclease (HEase) in group I introns and maturase for group H. In this study, Mexican Bacillus thuringiensis strains belong to the Universidad Autonoma de Nuevo Leon collection were evaluated for the presence of these introns. For this propose, specific primers were designed for group I introns inserted in the ribonucleotide reductase operon and group II introns B.th.I, Bth.I2and B.th.I3. The PCR results obtained with primers for group I, was a DNA band of 600 bp for most strains (fifty four) and one of 200 bp for six one. The nucleotide sequence of 600 pb DNA band revealed more than 95% homology with the amplicons and group I introns reported before. Concern to group II introns, we can not see PCR products correspond to expect DNA band size.