FIG 1.

Development of the BNA-PCR system to identify the clarithromycin resistance gene in Mycobacterium avium complex (MAC). (A) BNA-PCR on SmartCycler. The seven real-time PCRs were simultaneously carried out using a wild type (WT) template and six patterns of mutant templates. The BNA-PCR was able to identify only the WT sequence at a 22.69 threshold cycle value but not the mutants. (B) Sequences of the synthesized genes. A 237-bp fragment DNA of the WT as well as six forms of mutants between positions 2415 and 2650 in 23S rRNA of Mycobacterium avium were generated. At position 2058 or 2059 corresponding to Escherichia coli numbering the adenine (A) was replaced by a mutant (G, C, or T), as shown by the capital letters. (C) Agarose gel electrophoresis. The WT and six mutant sequences in panels A and B were identical as amplified by MAV_Fw2485 and MAV_Rv2631.