PPIases accelerate the folding of proteins. It catalyzes the cis-trans isomerization of proline imidic peptide bonds in oligopeptides. [protein]-peptidylproline (omega=180) = [protein]-peptidylproline (omega=0) Binds cyclosporin A (CsA). CsA mediates some of its effects via an inhibitory action on PPIase (By similarity). Ubiquitous, mostly in aerial organs. Repressed by the munition hexahydro-1,3,5-trinitro-1,3,5-triazine, also known as Royal Demolition eXplosive (RDX). Belongs to the cyclophilin-type PPIase family. Truncated N-terminus. Truncated C-terminus.