Structure based screening of ligands against dTDP-6-deoxy-D-xylo-4-hexulose 3, 5-epimerase (RmlC): phytochemical as drug candidate for Mycobacterium tuberculosis

Jyoti Prakash Rath, Mukesh Kumar Raval


Objective: RmlC (dTDP-6-deoxy-D-xylo-4-hexulose 3, 5-epimerase) is a crucial enzyme for cell wall biosynthesis in Mycobacterium tuberculosis. It’s absence in human host attest it as a valid target for drug designing. In the presented study an in-silico method is employed to find out the potential phytochemical inhibitors of RmlC.

Methods: AutoDock 4.2 is used to study the binding affinity of ligands in the active site of the protein. The drug-likeness and oral toxicity evaluation is done using the online tools Molsoft and ProTox respectively.

Results: Chrysophanol has binding affinity of -9.24 kcal/mole to RmlC active site. PASS tool predicts chrysophanol as antitubercular compound. Its druglikeness is 0.1, and toxicity class is 5 measured by ProTox. Hence, chrysophanol emerges as a lead molecule among the phytochemicals in the database.

Conclusions: Crysophanol is the lead inhibitor against RmlC target. The lead molecule may work as a successful drug in future for tuberculosis treatment.


RmlC, Tuberculosis, Crysophanol, Drug-likeness, Toxicity, Molsoft, ProTox

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