Virtual screening of curcumin and its analogs against the spike surface glycoprotein of SARS-CoV-2 and SARS-CoV

Abstract

COVID-19, a new pandemic caused by SARS-CoV-2, was first identified in 2019 in Wuhan, China. The novel corona virus SARS-CoV-2 and the 2002 SARS-CoV have 74% identity and use similar mechanisms to gain entry into the cell. Both the viruses enter the host cell by binding of the viral spike glycoprotein to the host receptor, angiotensin converting enzyme 2 (ACE2). Targeting entry of the virus has a better advantage than inhibiting the later stages of the viral life cycle. The crystal structure of the SARS-CoV (6CRV: full length S protein) and SARS-CoV-2 Spike proteins (6M0J: Receptor binding domain, RBD) was used to determine potential small molecule inhibitors. Curcumin, a naturally occurring phytochemical in Curcuma longa, is known to have broad pharmacological properties. In the present study, curcumin and its derivatives were docked, using Autodock 4.2, onto the 6CRV and 6M0J to study their capability to act as inhibitors of the spike protein and thereby, viral entry. The curcumin and its derivatives displayed binding energies, ΔG, ranging from −10.98 to −5.12 kcal/mol (6CRV) and −10.01 to −5.33 kcal/mol (6M0J). The least binding energy was seen in bis-demethoxycurcumin with: ΔG = −10.98 kcal/mol (6CRV) and −10.01 kcal/mol (6M0J). A good binding energy, drug likeness and efficient pharmacokinetic parameters suggest the potential of curcumin and few of its derivatives as SARS-CoV-2 spike protein inhibitors. However, further research is necessary to investigate the ability of these compounds as viral entry inhibitors.

Communicated by Ramaswamy H. Sarma

Keywords:

• Curcumin
• SARS-CoV-2
• SARS-CoV
• spike protein

Acknowledgements

We acknowledge the support rendered by the Department of Biochemistry, Indian Academy Degree College - Autonomous, Bengaluru and Ramanbhai Patel College of Pharmacy, Charotar University of Science and Technology, Gujarat for their support in carrying out this work.

Disclosure statement

The authors declare that they have no conflict of interests

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.