ABSTRACT
Restriction enzymes SpeI and XbaI were used in a pulsed-field gel electrophoresis (PFGE) study for molecular characterization of 146 clinical Burkholderia pseudomallei isolates. The PFGE parameters were optimized to enable comparable, reproducible, and robust results. The optimized parameters for both SpeI and XbaI restriction enzymes used in this study were 200 V and a pulse time of 5 to 65 s for a 28-h runtime. Using SpeI, 9 different clusters were identified, whereas 6 clusters were identified by XbaI digestion, which exhibited 85% similarity to SpeI. SpeI (discrimination index [D]=0.854) showed higher discriminatory power than XbaI did (D=0.464).
Subject(s)
Burkholderia pseudomallei/classification , Burkholderia pseudomallei/genetics , Deoxyribonucleases, Type II Site-Specific , Electrophoresis, Gel, Pulsed-Field/methods , Molecular Typing/methods , DNA, Bacterial/genetics , DNA, Bacterial/metabolism , Deoxyribonucleases, Type II Site-Specific/metabolism , Genotype , Humans , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
A patient with a clonal infection of Burkholderia pseudomallei had subpopulations with ceftazidime and amoxicillin-clavulanate susceptibilities that differed among the clinical specimens. Resistance was associated with a novel Cys69Tyr substitution in the Ambler class A beta-lactamase. Susceptibility testing of multiple colony variants from different sites should be performed for patients with culture-confirmed melioidosis.