Homology modeling and docking studies of novel drug candidate atovaquone on Babesia bovis dihydroorotate dehydrogenase (BbDHODH) receptor

Bovine babesiosis is one of most economically important tick borne disease across worldwide which is caused by an intra-erythrocytic apicomplexan parasite i.e. babesia bovis. Although different common chemotherapeutic drugs including imidazole, diproprionate and diminazene aceturate have been tried against this disease, but all these compounds do not produce their effect adequately and also there is induction drug resistance. In this work, we studied homology modeling and docking studies of a dihydroorotate dehydrogenase from bovis babesia, dimensional structure of the enzyme was built using MODELLER version 9.21 and docking study was performed under AutoDock platform. The protein model with lowest discrete potential energy (DOPE) -41275.21 Kcal/mol, was subjected to energy minimization and showed a good quality model. It has been resulted that the best docked Atovaquone confirmation with lowest binding energy (-9.73 kcal/mol) and lowest inhibition constant 73.57 μM had a number of amino acid residues such as Asp 264, Arg 267, Leu 270, Glu 293, Iso 324 and Gly 327 in close contact. This study was concluded that BbDHODH receptor would be a potential drug target for the novel drug atovaquone against B. bovis infection in dairy cattle.