Protease means the [[Protein]](or [[Enzyme]]) which degrades (poly)peptides into shorter peptide or [[AminoAcid]]s. Most frequent example is a digestion enzyme - chymotrypsin or trypsin.

Today, [[Protease]] is noticed as a drug for several [[Virus]] disease - [[AIDS]] , poliomyelitis or plant viral disease.
 
Protease is classified as nucleophile residue in the active site.

 1. SerineProtease 
 1. AspartylProtease
 1. CysteineProtease

Cleavege site of each protease
|| '''Reagent no.'''  ||   '''Reagent'''      ||           '''Cleavage rule'''  ||
||        1     ||  Trypsin       ||          C-term to K/R ||
||        2     ||  Lys-C         ||          C-term to K ||
||        3     ||  Arg-C         ||          C-term to R ||
||        4     ||  Asp-N         ||          N-term to D ||
||        5     ||  V8-bicarb     ||          C-term to E ||
||        6     ||  V8-phosph     ||          C-term to E/D ||
||        7     ||  Chymotrypsin  ||          C-term to F/W/Y/L/M ||
||        8     ||  CNBr          ||          C-term to M ||

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SeeAlso ViralProtease