Evaluation of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for identifying Burkholderia pseudomallei and Burkholderia thailandensis isolates

Since Burkholderia thailandensis is included in the reference spectra of the VITEK MS libraries rather than Burkholderia pseudomallei , B. pseudomallei cannot be correctly identified in the current version of VITEK MS. This study was undertaken to evaluate the utility of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) with the VITEK MS plus system in the detection of B. pseudomallei and B. thailandensis isolates. For each species, we increased the reference spectra, and then, a SuperSpectrum was created based on the selection of 39 specific masses. In a second step, we validated the SuperSpectra with 106 isolates identified by 16S rRNA gene sequencing. The results showed that there was 100% agreement between the validation strains analyzed by MALDI-TOF MS and those evaluated using 16S rRNA gene sequencing analysis methods. Therefore, MALDI-TOF MS is a promising, rapid, and economical method to monitor the outbreaks and spread of B. pseudomallei and B. thailandensis isolates.