Deletion of cagA gene of Helicobacter pylori by PCR products

Figure 3 A: Result of PCR amplified for diagnosing homologous recombination strains of cagA gene. Lanes 1-12 are 12 clones selected from chloramphenicol-resistant plates. Control is 26695 wild type. Twelve clones were all negative for diagnostic primers B1-2 while control is positive, suggesting that the flanking region of cagA gene of all the selected clones was deleted; B: Result of PCR amplified for positive control of homologous recombination strains of cagE gene. Lanes 1-12 are 12 clones selected from chloramphenicol-resistant plates. Control is 26695 wild type. Twelve clones were all positive of cagE gene; C: Result of Southern blot for diagnosing homologous recombination strains of cagA gene. Lanes 1-12 are 12 clones selected from chloramphenicol-resistant plates. Control is 26695 wild type. All the 12 clones except 3, 5, and 9 were positive hybridization with probes of chloramphenicol-resistant gene while control was negative.