IUBMB Enzyme Nomenclature


Accepted name: peptidylprolyl isomerase

Reaction: peptidylproline (ω=180) = peptidylproline (ω=0)

Glossary: For definition of ω, click here

Other name(s): PPIase; cyclophilin [misleading, see comments]; peptide bond isomerase; peptidyl-prolyl cis-trans isomerase

Systematic name: peptidylproline cis-trans-isomerase

Comments: The first type of this enzyme found [1] proved to be the protein cyclophilin, which binds the immunosuppressant cyclosporin A. Other distinct families of the enzyme exist, one being FK-506 binding proteins (FKBP) and another that includes parvulin from Escherichia coli. The three families are structurally unrelated and can be distinguished by being inhibited by cyclosporin A, FK-506 and 5-hydroxy-1,4-naphthoquinone, respectively.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 95076-93-0


1. Fischer, G. and Bang, H. The refolding of urea-denatured ribonuclease A is catalyzed by peptidyl-prolyl cis-trans isomerase. Biochim. Biophys. Acta 828 (1985) 39-42. [PMID: 3882150]

2. Fischer, G., Bang, H. and Mech, C. [Determination of enzymatic catalysis for the cis-trans-isomerization of peptide binding in proline-containing peptides]. Biomed. Biochim. Acta 43 (1984) 1101-1111. [PMID: 6395866]

3. Fischer, G., Wittmann-Liebold, B., Lang, K., Kiefhaber, T. and Schmid, F.X. Cyclophilin and peptidyl-prolyl cis-trans isomerase are probably identical proteins. Nature 337 (1989) 476-478. [PMID: 2492638]

4. Takahashi, N., Hayano, T. and Suzuki, M. Peptidyl-prolyl cis-trans isomerase is the cyclosporin A-binding protein cyclophilin. Nature 337 (1989) 473-475. [PMID: 2644542]

5. Hennig, L., Christner, C., Kipping, M., Schelbert, B., Rucknagel, K.P., Grabley, S., Kullertz, G. and Fischer, G. Selective inactivation of parvulin-like peptidyl-prolyl cis/trans isomerases by juglone. Biochemistry 37 (1998) 5953-5960. [PMID: 9558330]

6. Fischer, G. Peptidyl-prolyl cis/trans isomerases and their effectors. Angew. Chem. Int. Ed. Engl. 33 (1994) 1415-1436.

7. Harrison, R.K. and Stein, R.L. Substrate specificities of the peptidyl prolyl cis-trans isomerase activities of cyclophilin and FK-506 binding protein: evidence for the existence of a family of distinct enzymes. Biochemistry 29 (1990) 3813-3816. [PMID: 1693856]

8. Eisenmesser, E.Z., Bosco, D.A., Akke, M. and Kern, D. Enzyme dynamics during catalysis. Science 295 (2002) 1520-1523. [PMID: 11859194 ]

[EC created 1989, modified 2002]

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