In silico binding analysis of lutein and rosmarinic acid against envelope domain III protein of dengue virus.

OBJECTIVE: The study was performed to evaluate in silico binding ability of lutein and rosmarinic acid (RA) with the envelope domain III (EDIII) proteins of the four serotypes of dengue virus (DENV), enlightening potential antiviral activity of the two compounds. MATERIALS AND METHODS: EDIII protein structures for the four DENV serotypes were retrieved from RCSB Protein data bank (PDB) and used as receptors. Four ligands of lutein and four of RA were selected from the ZINC database and used for computational molecular docking and ligand interaction analysis with the four receptors using bioinformatics tools like AutoDock Vina and Molecular Operating Environment (MOE) software. RESULTS: The EDIII of the four serotypes demonstrated significant interaction with ligands of lutein and RA. RA ligand ZINC899870, particularly presented best-binding energy values of 6.4, -7.0, and 6.9 kcal/mol with EDIII of serotype DENV-1, DENV-2, and DENV-4 respectively. Whereas, lutein ligand, ZINC14879959 presented best-binding energy value of 7.9 kcal/mol for EDIII of serotype DENV-3. From the results predicted by MOE, the hydroxyl (OH) of 3, 4-dihydroxyphenyl group of RA ligand ZINC899870 is actively involved in interaction with all four serotypes. CONCLUSION: RA is a competent candidate for further evaluation of potential in vitro antiviral activity that can be effective in conferring protection against the four serotypes of DENV.