Improved flagellin genotyping in the Burkholderia cepacia complex

Oligonucleotide primers designed to N- and C-terminal sequences of Burkholderia cepacia complex fliC genes were used to amplify and sequence fliC genes from a strain of Burkholderia vietnamiensis and three isolates of Burkholderia multivorans with large fliC genes. Alignments incorporating the new sequences enabled the design of polymerase chain reaction (PCR) primers for extension of a published PCR/restriction fragment length polymorphism typing method, to include isolates that previously failed to yield fliC amplicons. Most B. vietnamiensis isolates and hitherto non-typable Burkholderia cenocepacia isolates contained much smaller fliC genes than previously reported. Although B. multivorans strains with larger fliC genes clustered together, relationships between strains based on fliC sequences did not generally correlate with genomovar status.