Identification and Characterization of Burkholderia pseudomallei

Blood samples collected from patients were subjected to the BACTEC blood culture system according to the manufacturer’s instructions (Becton Dickinson, USA). Positive growth was subcultured onto blood agar, chocolate agar and MacConkey agar. Samples from other sources (pus, sputum, endotracheal secretions, pleural fluid) were cultured directly on blood agar, chocolate agar and MacConkey agar. B. pseudomallei was initially identified with either API20NE (BioMérieux, France) or BBL Crystal Identification Systems (Becton Dickinson, USA), and confirmed with real-time PCR targeting TTS1, as described previously [22 (link)]. Antibiotic susceptibility of B. pseudomallei isolates were determined by the Kirby-Bauer disk diffusion susceptibility test (Becton Dickinson, USA) and/or E-tests (BioMérieux, France). Multilocus sequence typing (MLST) was performed as described previously [23 (link)]. The presence of nucleotide sequences encoding Burkholderia intracellular motility factor A (BimA_Bm or BimA_Bp) and filamentous hemagglutination genes (FhaB3), and the Burkholderia thailandensis-like flagellum and chemotaxis (BTFC) and the Yersinia-like fimbrial (YLF) gene clusters were determined using previously published methods [24 (link)].