Sunflower Trypsin Monocyclic Inhibitor Selected for the Main Protease of SARS-CoV-2 by Phage Display.

Main protease (Mpro), also known as 3-chymotrypsin-like protease (3CLpro), is a nonstructural protein (NSP5) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) responsible for the cleavage of virus polyproteins during viral replication at 11 sites, which generates 12 functional proteins. Mpro is a cysteine protease that presents specificity for the amino acid residue glutamine (Gln) at the P1 position of the substrate. Due to its essential role in processing the viral polyprotein for viral particle formation (assembly), Mpro inhibition has become an important tool to control coronavirus disease 2019 (COVID-19), since Mpro inhibitors act as antivirals.

Boophilin D1, a Kunitz type protease inhibitor, as a source of inhibitors for the ZIKA virus NS2B-NS3 protease.

Arboviruses are a global concern for a multitude of reasons, including their increased incidence and human mortality. Vectors associated with arboviruses include the mosquito Aedes sp., which is responsible for transmitting the Zika virus.