Discovery of Putative GyrB Inhibitors against Mycobacterium tuberculosis: A Combined Virtual Screening and...

With the rapid emergence of drug-resistant strains of tuberculosis, resistance to current first-line and second-line anti-tuberculosis drugs is becoming increasingly prevalent. Consequently, the discovery of new lead compounds is essential to address this challenge. GyrB has emerged as a promising target for tuberculosis treatment due to its pivotal role in DNA replication and topology regulation in Mycobacterium tuberculosis.

In this study, a multi-conformational virtual screening approach, complemented by antibacterial activity assays, was utilized to identify novel GyrB inhibitors from the ChemDiv database.

Among the 27 compounds purchased, 10 exhibited significant inhibitory effects against the H37Rv strain, with 8 featuring novel core scaffolds. Notably, three compounds (V027-7669, V017-8710, and 5132-0213) demonstrated a minimum inhibitory concentration (MIC) of 8 μg/mL. Compounds V027-7669 and V017-8710, in particular, showed antibacterial activity against a multidrug-resistant tuberculosis strain, with MIC values of 32 μg/mL and 16 μg/mL, respectively. Molecular dynamics simulations revealed that both V027-7669 and V017-8710 bind stably to GyrB, which are primarily driven by nonpolar interactions. Furthermore, both of them occupy a novel sub-pocket formed by residues Val99, Gly106, Val123, Gly124, and Val125, where they establish hydrogen bonds with Val125.

Our study underscores the effectiveness of a multi-conformational virtual screening strategy in identifying novel GyrB inhibitors and suggests V027-7669 and V017-8710 as promising lead compounds for the development of treatments against multidrug- resistant tuberculosis.