Vag8, a Bordetella pertussis bvg-Regulated Protein

Bordetella pertussis expresses a bvg-regulated 95-kDa protein, Vag8, encoded by vag-8. Southern blot analysis indicates that strains of Bordetella bronchiseptica and Bordetella parapertussis have DNA homologous to vag-8. Antiserum raised to a fusion of maltose binding protein to an N-terminal 60-kDa fragment of Vag8 recognizes the native 95-kDa protein in immunoblots of B. pertussis and B. bronchiseptica but not B. parapertussis. A 95-kDa protein-negative derivative of B. pertussis 18323 containing a deletion of vag-8 colonized mice as efficiently as the parent B. pertussis strain in a mouse aerosol model of pertussis.