) translated from the viral genome into individual, functional non-structural proteins (nsps).
: Mpro is unique in that it first cleaves itself out of the polyprotein chain (autoproteolysis) before it begins processing other sites. ) translated from the viral genome into individual,
The , also referred to as 3CLpro (3-chymotrypsin-like protease) or nsp5 , is a critical enzyme required for the replication and survival of coronaviruses, most notably SARS-CoV-2 . Because it plays an indispensable role in the viral life cycle and lacks a close human equivalent, it has become one of the most significant targets for antiviral drug development. Biological Function and Mechanism Mpro is responsible for processing large polyproteins ( pp1ap p 1 a pp1abp p 1 a b Because it plays an indispensable role in the
Mpro typically exists as a , meaning it consists of two identical protein subunits. This dimerization is essential for its catalytic activity . : It recognizes a specific sequence, typically requiring
: It recognizes a specific sequence, typically requiring a Glutamine (Gln) at the P1 position , a hydrophobic residue like Leucine (Leu) at P2, and a small amino acid (Ser, Ala, or Gly) at the P1' position. Structural Features
: The protease cleaves the polyprotein at at least 11 conserved sites , releasing essential proteins that form the viral replication-transcription complex.