Conservation of the 17-kilodalton antigen gene within the genus XXXX .

@entity1 @entity12357 @entity50034 @entity377 @entity2711 @entity1892 @entity11102 @entity30867
The 17-kDa antigen of @entity2711 has previously been shown to elicit a strong humoral immune response in @entity1 with @entity11102 ( @entity11102 ) and to be useful in screening human serum samples for @entity11102 . In this study, PCR amplification of genes homologous to the 17-kDa antigen gene of @entity2711 was performed using genomic DNAs from several species of @entity30867 , including the currently recognized @entity1 pathogens. Amplicons of similar size were demonstrated using the following chromosomal DNA templates: @entity2711 (two strains), @entity30867 (two strains), B. elizabethae, @entity50034 , @entity1892 . berkhoffii. No evidence of a @entity12357 homolog of the 17-kDa antigen gene was obtained using multiple primer pairs. DNA sequencing revealed open reading frames capable of coding for proteins with sizes similar to that of the 17-kDa antigen of @entity2711 in all of the amplicons; however, extensive sequence divergence across the genus was noted. Cloning of the amplified products into pUC19 resulted in recombinants that directed synthesis of homologs of the 17-kDa protein. Immunoblot analysis using @entity1 sera from @entity11102 cases demonstrated very little cross-reactivity among different species for this protein. In contrast, immunoblots using rabbit serum raised to the recombinant B. henselae antigen showed extensive cross-reactivity with the proteins of other @entity30867 species. The data suggest that the use of the 17-kDa antigen as a serologic reagent may allow the development of more specific diagnostic assays. Furthermore, the @entity377 sequences from the various versions of the 17-kDa antigen gene should be useful for rapid identification of @entity30867 at the species level.
