Development of the Quantitative Real-Time PCR Assay for the Detection of Mycobacterium xenopi

A quantitative real-time polymerase chain reaction (qPCR) assay using SYBR Green was developed for the detection of the internal transcribed spacer (ITS) of 16S-23S rDNA region in Mycobacterium xenopi (M. xenopi). The qPCR assay for the detection of the M. xenopi DNA had a crossing point (Cp) of 14.17 ± 0.07 and a melting peak (Tm) of 90.23 ± 0.03°C. As for other mycobacterial species, the Cp and Tm values were above 21 and below 86°C, respectively. The Tm values of 89.47 to 90.03oC could be used to detect M. xenopi and differentiate M. xenopi from other mycobacterial species.