Figure 3.

Biofilm production for Burkholderia pseudomallei strain ATS2021, the causative strain in an outbreak of 4 cases, 2 of them fatal, in the United States in 2021, in relation to other previously characterized B. pseudomallei clinical isolates. Biofilm formation of bacterial strains was assessed by crystal violet staining as measured by OD₆₀₀. Biofilm was allowed to form after static growth in LB+4% glycerol for 1 day at 37°C. Clinical isolates used in this assay originated from Thailand (red bars) or Australia (green bars). Error bars represent the SEs from mean values determined from 4 independent assays. ATS2021 formed significantly more biofilm under these conditions compared to all isolates except MSHR5848 as determined by a linear mixed effects model. OD₆₀₀, optical density at 600 nm.