Molecular docking of theaflavin-3-gallate metabolite with protein kinase A, ESX-1 system, and ESX-1 secreted protein B (EspB) of Mycobacterium tuberculosis

Molecular docking of major virulence factors of bacteria by bioactive compounds has obtained huge attention in molecular docking studies. Theaflavin-3-gallate related to the polyphenolic bioflavonoid class isolated from Camellia sinensis leaves has demonstrated anti-inflammatory, anticancer, antibacterial, and antiviral activities as important therapeutic properties. There are several main virulence factors for Mycobacterium tuberculosis, the causative agent of tuberculosis. In the present study, protein kinase A, ESX-1 system, and ESX-1 secreted protein B (EspB) were opted to survey molecular docking interaction upon theaflavin-3-gallate. This investigation revealed that different docking scores resulted from CB-Dock2 and AutoDock Vina. CB-dock2 results demonstrated a higher affinity of theaflavin-3-gallate ligand with protein kinase A receptor. In contrast, based on the results of AutoDock Vina, there was the highest binding affinity for the ESX-1 system receptor with a binding energy of -10.1 kcal/mol. Moreover, the STRING database demonstrated higher scores of 0.998 and 0.995 for pstp and EspL for protein kinase A and EspB, respectively.