Calcium-dependent protein kinase 1 (CDPK1) (TgCDPK1)

Calcium-dependent protein kinase 1 (CDPK1) is a vital signaling enzyme in the apicomplexan parasite Toxoplasma gondii, where it acts as a master regulator of the lytic cycle. It is essential for the secretion of micronemes, specialized organelles that release proteins required for the parasite's gliding motility, host cell invasion, and egress from infected cells. Unlike human kinases, TgCDPK1 possesses a unique glycine gatekeeper residue in its ATP-binding pocket, which creates a small hydrophobic subpocket. This structural divergence allows for the development of bumped kinase inhibitors (BKIs) that selectively inhibit the parasite enzyme with minimal impact on host kinases. Inhibition of TgCDPK1 effectively halts the progression of toxoplasmosis by preventing the parasite from entering new cells or escaping from current ones. While no CDPK1 inhibitors are currently approved for clinical use, several candidates like BKI-1294 have shown significant efficacy in animal models of both acute and congenital toxoplasmosis. Research continues to focus on optimizing these inhibitors for safety and overcoming potential resistance mechanisms, such as mutations at the gatekeeper residue.

Other names

Toxoplasma gondii calcium-dependent protein kinase 1CDPK1TgCDPK1Calcium-dependent protein kinase 1

ATP-competitive inhibition of the parasite kinase, specifically targeting the unique glycine gatekeeper residue to block microneme discharge and host cell entry/exit.