RFLP AND SEQUENCE ANALYSIS REVEALS HETEROGENEITY AMONG THE PERTACTIN GENES OF BORDETELLA BRONCHISEPTICA VACCINE AND FIELD STRAINS

摘要

The role of B. bronchiseptica in atrophic rhinitis (AR) and primary bronchopneumonia in young pigs is well-documented (1), Infection with this agent also increases the frequency and severity of respiratory disease due to other pathogens (1,2), including PRRSV (3). Efforts to improve the efficacy of B. bronchiseptica vaccines could have a significant impact on overall respiratory health in swine. The product of the B. bronchiseptica pertactin gene (prn) has been implicated as an adhesin and protective immunogen. Previous analysis of prn revealed 2 regions that encode amino acid repeat motifs (4). Region 1, approximately 800 bp from the 5' end of prn, contains the repeat GGXXP_n. Region 2, roughly 900 bp 3' of Region 1, encodes a reiterated PQP_n. Variation in Region 1 of prn from Bordetella pertussis has been postulated to account for recently observed decreases in vaccine efficacy in humans (5). Variation in B. bronchiseptica prn has not been evaluated. The goal of this study was to determine whether heterogeneity exists in Regions 1 and 2 of prn genes from vaccine and field strains of B. bronchiseptica.