The Babesia bovis BvP36 gene is expressed at least in the asexual stage of Babesia merozoite

摘要

Recently, Babesia bovis genome project identified a novel gene, which is homologous to the gene encoding sporozoite P36 antigen in Plasmodium parasites. In the present study, we isolated the P36 homologous gene from the genomic DNA of B. bovis and designated it as the BvP36 gene. The sequence of the BvP36 gene was identical to that reported previously. This gene was expressed in an Escherichia coli system to produce a recombinant protein (rBvP36). The rBvP36 protein was produced as a highly soluble form in E. coli and was detected by western blot analyses of sera collected from cattle experimentally infected with B. bovis and B. bigemina merozoites. In indirect immunofluorescence tests, sera collected from mice immunized with rBvP36 showed strong reactions to both B. bovis and B. bigemina merozoites. Our results indicate that the BvP36 antigen is expressed at least in the asexual merozoite stage of B. bovis and suggest that B. bigemina merozoite carries an antigen similar to BvP36.