mallei, B pseudomallei, B, thailandensis, B. ambifaria, B. cenocepacia, B. dolosa, B. glathe, B. multivorans, B. stabilis). Seven more masses (3,655 [doubly charged 7,309], 5,195, 6,551, 7,169, 7,309, 8,628 and 9,713 Da) were present in all B. mallei and B. pseudomallei samples but also in one or more of the other Burkholderia species. Considering VX-680 manufacturer the close relation of B. thailandensis with B. mallei and B. pseudomallei, mass 9,713 Da is of interest, which was specific for all B. mallei, B. pseudomallei, and B. thailandensis samples, i.e. the Pseudomallei group. Finally, 6,551 Da was present in all B. mallei and B. pseudomallei samples but in none of the other species, making it an effective discriminator
between the B. mallei/pseudomallei group and the other representatives of the genus Burkholderia. Concerning the distinction of B. mallei and B. pseudomallei, statistical analysis with ClinProTools 3.0 software revealed a SBE-��-CD supplier number of masses with significant class separation
between the two species based on peak intensity. Most significant separation could be obtained based on the masses 7,553 and 5,794 which differ significantly in intensity between the two species. Discussion In recent years MALDI-TOF MS has been introduced WH-4-023 cost in microbiological laboratories as a time saving diagnostic approach supplementing morphological, biochemical, and molecular techniques for identification of microbes . In several studies the comparability with conventional identification procedures was assessed with generally good correlation,
but discordances were seen on the species and even on the Grape seed extract genus level [24, 25]. This proteomic profiling approach was successfully applied in routine identification of bacterial isolates from blood culture with the exception of polymicrobial samples and streptococci . The identification of Burkholderia spp. and other non-fermenting bacteria using MALDI-TOF MS was investigated in cystic fibrosis (CF) patients as Burkholderia spp. (mainly of the cepacia-complex) cause a relevant number of life-threatening infections in these patients [27–29]. It was demonstrated that MALDI-TOF MS is a useful tool for rapid identification in the routine laboratory. B. pseudomallei can be the cause of melioidosis in CF patients and travelers to tropical regions, but this bacterium and the closely related species B. mallei was not included in previous MALDI-TOF MS studies [18–22, 30, 31]. Natural catastrophes like the tsunami in Indonesia (2004) and occasional flooding in other tropical regions resulted in elevated incidence of melioidosis and several cases among travelers and tourists [32–36]. B. mallei and B. pseudomallei are biological agents which further underlines the need for rapid detection tools. Identification of Burkholderia ssp. and distinction of B. mallei and B. pseudomallei from other species was feasible.