Survival of Burkholderia pseudomallei in distilled water for 16 years

Burkholderia pseudomallei was examined after being maintained in distilled water at 25 °C for 16 years. The Gram stain was atypical (pale pink cocci or coccobacilli). The estimated number of live and dead B. pseudomallei was 3.8 × 10 7 cells/ml and 1.4 × 10 5 cells/ml, respectively. A colony count on agar of 1.0 × 10 6 cfu/ml suggested that a proportion of cells were in a viable but non-culturable state. Colony morphology was different from the parental isolate for 84% of colonies. Pulsed-field gel electrophoresis analysis of AvrII DNA restriction fragments revealed six different but related banding patterns, which may represent genomic rearrangement.