Endopeptidase
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(Redirected from Endopeptidases)
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Endopeptidase or endoproteinase are proteolytic peptidases that break peptide bonds of nonterminal amino acids (i.e. within the molecule), in contrast to exopeptidases, which break peptide bonds from end-pieces of terminal amino acids.[1] For this reason, endopeptidases cannot break down peptides into monomers, while exopeptidases can break down proteins into monomers. A particular case of endopeptidase is the oligopeptidase, whose substrates are oligopeptides instead of proteins.
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. Works best at pH 8.
- Chymotrypsin - cuts after Phe, Trp, or Tyr, unless followed by Pro. Cuts more slowly after His, Met or Leu. Works best at pH 8.
- 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.
- Glutamyl endopeptidase - cuts after Glu. Works best at pH 8.
- Neprilysin
References
[edit]- ^ "endopeptidase". Merriam-Webster. Archived from the original on 21 December 2016. Retrieved 18 January 2017.
- Endopeptidases at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
See also
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