VARIATION IN FLAGELLIN GENES AND PROTEINS OF BURKHOLDERIA-CEPACIA

The majority of isolates of Burkholderia cepacia, an important opportu nistic pathogen associated with cystic fibrosis, can be classified int o two types on the basis of flagellin protein size, Electron microscop ic analysis indicates that the flagella of strains with the larger fla gellin type (type I) are wider in diameter, Flagellin genes representa tive of both types were cloned and sequenced to design oligonucleotide primers for PCR amplification of the central variable domain of B cep acia flagellin genes. PCR-restriction fragment length polymorphism ana lysis of amplified B, cepacia flagellin gene products from 16 strains enabled flagellin type classification on the basis of product size and revealed considerable differences in sequence, indicating that the fl agellin gene is a useful biomarker for epidemiological and phylogeneti c studies of this organism.