The picornaviral 3C proteinases: cysteine nucleophiles in serine proteinase folds

Protein Sci. 1995 Aug;4(8):1439-45. doi: 10.1002/pro.5560040801.


The 3C proteinases are a novel group of cysteine proteinases with a serine proteinase-like fold that are responsible for the bulk of polyprotein processing in the Picornaviridae. Because members of this viral family are to blame for several ongoing global pandemic problems (rhinovirus, hepatitis A virus) as well as sporadic outbreaks of more serious pathologies (poliovirus), there has been continuing interest over the last two decades in the development of antiviral therapies. The recent determination of the structure of two of the 3C proteinases by X-ray crystallography opens the door for the application of the latest advances in computer-assisted identification and design of anti-proteinase therapeutic/chemoprophylactic agents.

Publication types

  • Review

MeSH terms

  • Binding Sites
  • Catalysis
  • Cysteine / chemistry*
  • Cysteine Endopeptidases / chemistry*
  • Cysteine Endopeptidases / metabolism
  • Picornaviridae / enzymology*
  • Protein Folding
  • Serine Endopeptidases / chemistry*
  • Substrate Specificity
  • Viral Proteins*


  • Viral Proteins
  • Serine Endopeptidases
  • Cysteine Endopeptidases
  • 3C proteases
  • Cysteine