CHROMOSOMAL DNA FROM BOTH FLAGELLATE AND NON-FLAGELLATE BORDETELLA SPECIES CONTAINS SEQUENCES HOMOLOGOUS TO THE SALMONELLA H1-FLAGELLIN GENE

The genus Bordetella contains four species: two are non-motile, the hu man pathogens B. pertussis and B. parapertussis; and two are motile, t he broad host-range mammalian pathogen B. bronchiseptica, and the avia n pathogen B. avium. The motility of the latter two species is due to peritrichous flagella. Here we show that strains of all four species c ontain DNA sequences homologous to flagellin genes. Two types of gene probe were hybridised to Bordetella chromosomal DNA in Southern blots: the structural gene for H1 flagellin of Salmonella typhimurium and an oligonucleotide derived from the conserved N-terminal amino acid sequ ences of various flagellin proteins. ClaI-digested DNA from all four B ordetella species hybridised with both probes in Southern blots, altho ugh each species gave a characteristic pattern of hybridisation. This indicates that the non-motile B. pertussis and B. parapertussis specie s contain non-expressed flagellin genes.