Characterization of Calcium-Dependent Protein Kinases 3, a Protein Involved in Growth of

Calcium-dependent protein kinases (CDPKs) are considered promising targets for pharmaceutical intervention of cryptosporidiosis. Whole-genome sequencing has revealed the presence of several CDPKs (CDPKs) in . In this study, we expressed recombinant CDPK3 encoded by the gene in . The biologic characteristics and functions of CDPK3 were examined using qRT-PCR, immunofluorescence microscopy, and neutralization assay. The expression of the gene peaked in merozoites during culture while the CDPK3 protein was expressed in both sporozoites and merozoites. Polyclonal antibodies against CDPK3 showed no significant inhibitory effects on host invasion by the parasites. We assessed the inhibitory effects of 46 candidate compounds from molecular docking of CDPK3 on both development and CDPK3 enzyme activities. One compound was identified to be effective. Results of these analyses suggest that CDPK3 might play an important role in the growth of .