PMID: 26656689

Authors:

Wang F, Chen C, Liu X, Yang K, Xu X, Yang H

Title:

The crystal structure of feline infectious peritonitis virus main protease in complex with synergetic dual inhibitors.

Journal:

J Virol. 2015 Dec 9. pii: JVI.02685-15.

Abstract:

Coronaviruses (CoVs) can cause highly prevalent diseases in humans and animals. Feline infectious peritonitis virus (FIPV) belongs to genus alphacoronavirus, resulting in a lethal systemic granulomatous disease called FIP, which is one of the most important fatal infectious diseases of cats worldwide. No specific vaccines or drugs have been approved to treat FIP. CoV main proteases (Mpros) play a pivotal role in viral transcription and replication, making them an ideal target for drug development. Here we report the crystal structure of FIPV Mpro in complex with dual inhibitors, a zinc ion and a Michael acceptor. The complex structure elaborates a unique mechanism of two distinct inhibitors synergizing to inactivate the protease, providing structural basis to design novel antivirals and suggesting the potential to take advantage of zinc as an adjunct therapy against CoV-associated diseases. IMPORTANCE: Coronaviruses (CoVs) have the largest genome among all RNA viruses. CoV infection causes various diseases in human and animals, including severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). No approved specific drugs or vaccinations are available to treat their infections. Here we report a novel dual inhibition mechanism targeting CoV main protease (Mpro) from feline infectious peritonitis virus (FIPV), which leads to lethal systemic granulomatous disease in cats. Mpro, conserved across all CoV genomes, is essential for viral replication and transcription. We demonstrated that zinc ion and a Michael-acceptor based peptidomimetic inhibitor synergistically inactivate FIPV Mpro. We also solved the structure of FIPV Mpro complexed with two inhibitors, delineating the structural view of dual inhibition mechanism. Our study provides new insight into the pharmaceutical strategy against CoV Mpro through using zinc as an adjuvant therapy to enhance the efficacy of irreversible peptidomimetic inhibitor.