PLpro employs a catalytic triad mechanism involving a cysteine residue as the nucleophile, a histidine residue as a general base, and an asparagine or aspartate residue to stabilize the transition state. The enzyme cleaves peptide bonds in the viral polyprotein, releasing mature viral proteins necessary for replication and assembly. The catalytic process involves the formation of a covalent intermediate between the enzyme and the substrate, followed by hydrolysis to release the cleaved products.
