Prolyl isomerase
Prolyl isomerase (also known as peptidylprolyl isomerase or PPIase) is an enzyme (EC 5.2.1.8) found in both prokaryotes and eukaryotes that interconverts the cis and trans isomers of peptide bonds with the amino acid proline. Proline has an unusually conformationally restrained peptide bond due to its cyclic structure with its side chain bonded to its secondary amine nitrogen. Most amino acids have a strong energetic preference for the trans peptide bond conformation due to steric hindrance, but proline's unusual structure stabilizes the cis form so that both isomers are populated under biologically relevant conditions. Proteins with prolyl isomerase activity include cyclophilin, FKBPs, and parvulin, although larger proteins can also contain prolyl isomerase domains.
| Peptidylprolyl isomerase | |||||||||
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| Identifiers | |||||||||
| EC no. | 5.2.1.8 | ||||||||
| CAS no. | 95076-93-0 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
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| Peptidyl-prolyl cis-trans isomerase, PpiC-type | |||||||||
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| Identifiers | |||||||||
| Symbol | PPIase_PpiC | ||||||||
| Pfam | PF00639 | ||||||||
| InterPro | IPR000297 | ||||||||
| PROSITE | PDOC00840 | ||||||||
| Membranome | 599 | ||||||||
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