Pathogenic Leishmania secrete antigenically related chitinases which are encoded by a highly conserved gene locus

Recently, we identified and characterized a single-copy chitinase gene (LdC ht1) from Leishmania donovani, a protozoan pathogen of humans. It has been hypothesized that this parasite enzyme plays a critical role in the surviva l of all Leishmania species within their sandfly vectors and for their tran smission to humans. Thus, in the current study, pulse-field gel electrophor esis and Southern hybridization with the LdCht1 gene probe were used to dem onstrate that this chitinase gene has been conserved across species lines o f various pathogenic Leishmania. Further, immunoprecipitation and enzyme ac tivity assays using an anti-LdCht1-peptide serum were used to show that the chitinases produced and released by this group of parasites possessed both highly conserved antigenic epitopes and enzyme activities. Results of thes e studies demonstrate that the chitinase gene locus and enzyme activity hav e been conserved across species lines among this group of human pathogens.