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ENZYME

ENZYME entry: EC 3.4.26.2

PURL: https://purl.expasy.org/enzyme/EC/3.4.26.2
Accepted Name
scytalidoglutamic peptidase
Alternative Name(s)
scytalidocarboxylpeptidase-B
scytalidopepsin-B
Reaction catalysed
Hydrolysis of proteins, with a strong preference for Phe or Tyr at position P1 and one of the smaller amino-acids at P1' in the sequence -P3 - P2 - P1 -|-P1'- P2'- P3'-. Cleaves the Tyr(26)-Thr(27) bond in the B chain of oxidized insulin, which is not cleaved by pepsin
Comment(s)
  • The enzyme, isolated from the fungus Scytalidium lignicola and found in several other fungi, has a low pH optimum, being most active at pH 2 with casein as substrate.
  • It differs from the EC 3.4.23.1 and EC 3.4.23.2 in being insensitive to inhibition by pepstatin. It also differs from mammalian pepsins in showing a preference for a positively charged residue (Lys or Arg) at the P3 position.
  • In addition to the catalytic Glu residue, a Gln residue appears to play an important role in the hydrolytic mechanism.
  • A member of peptidase family G01, the "eqolisin" family of glutamic peptidases (G01.0001).
Cross-references
BRENDA3.4.26.2
EC2PDB3.4.26.2
ExplorEnz3.4.26.2
KEGG Ligand Database for Enzyme Nomenclature3.4.26.2
IUBMB Enzyme Nomenclature3.4.26.2
MEDLINEFind literature relating to 3.4.26.2
MetaCyc3.4.26.2
Rhea expert-curated reactions3.4.26.2

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All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 3.4.26.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 3.4.-.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 3.-.-.-