Abstract

Diospyrin, the compound under research binds to a novel site on well known enzyme DNA Gyrase of Mycobacterium tuberculosis and inhibits the enzyme. The aim of the present study was to predict the binding energies/interactions between Diospyrin compound and different target proteins of Mycobacterium tuberculosis. The following target proteins with their Protein Data Bank (PDB) ID were selected, NADH-dependent enoyl- ACP reductase  (InhA) - 2NSD, Adenosine kinase (Adok) - 2PKK, Mycolic acid synthase (PcaA) - 1L1E, Lysine N-acetyltransferase (MbtK) - 1YK3, Thymidylate synthase X (ThyX) - 3GWC, Thymidylate kinase (TmK) – 1G3U, Serine/threonine-protein kinase (PknG) – 2PZI, beta-ketoacyl-ACP synthase III (FabH) – 1HZP, Arabinosyl indolyl acetyl inositol synthase (EmbC) – 3PTY, dTDP-rhamnose synthase (RmlD) – 1KC3, Cyclopropane fatty acid synthase (CmaA2) – 3HEM, Diaminopimelate decarboxylase (LysA) – 1HKV, L,D-Transpeptidase type 2 ^_ 3VAE, Gyrase type IIA topoisomerase C-terminal domain ^_ 3UC1 and Topoisomerase IV (E.coli) _ 3FV5 to study their susceptibility to Diospyrin compound. The 3D and 2D structures of target proteins are downloaded from PDB database. The extent of binding positions and affinity of the Diospyrin with the selected target proteins were predicted based upon the scoring functions - Glide score (G Score) of Glide software.  The Cyclopropane fatty acid synthase (CmaA2) was identified as potential target enzyme through our molecular docking studies. Structure-based drug design is now becoming the effective tool with the potential to identify the lead molecule to the development of new anti-tubercular agents, effective against persistent and resistant Mycobacterium tuberculosis infections.