|This article may require cleanup to meet Wikipedia's quality standards.
Please improve this article if you can.
Endopeptidase or endoproteinase are peptidases that break peptide bonds within the molecule, in contrast to exopeptidases, which break peptide bonds from their end-pieces. Thus, endopeptidases cleave peptides.
They are usually very specific for certain amino acids.
Examples of endopeptidases include:
- Trypsin - cuts after Arg or Lys, unless followed by Pro. Very strict.
- Chymotrypsin - cuts after Phe, Trp, or Tyr, unless followed by Pro. Cuts more slowly after Asn, His, Met or Leu.
- Elastase - cuts after Ala, Gly, Ser, or Val, unless followed by Pro.
- Thermolysin - cuts before Ile, Met, Phe, Trp, Tyr, or Val, unless preceded by Pro. Sometimes cuts after Ala, Asp, His or Thr. Heat stable.
- Pepsin - cuts before Leu, Phe, Trp or Tyr, unless preceded by Pro. Also others, quite nonspecific; works best at pH 2.
- Endopeptidase V8 - cuts after Glu.