Requirements for peptidyl‐prolyl isomerization activity: A comprehensive mutational analysis of the substrate‐binding cavity of FK506‐binding protein 12

• DOI: 10.1110/ps.073203707
• Publication Date: 2007-11-20T15:30:14Z
• Authors: Teikichi Ikura; Nobutoshi Ito
• Keywords: FKBP

Peptidyl-prolyl isomerase (PPIase) activity is exhibited by many proteins belonging to the PPIase family. However, catalytic mechanism of this remains be completely elucidated. Here, we selected human FK506-binding protein 12 (FKBP12) as model and investigated nature amino acid residues essential for activity. The crystal structures several complexes with short peptides revealed that Asp37, Arg42, Phe46, Val55, Trp59, Tyr82 in substrate-binding cavity FKBP12 appear play key roles Each these six was substituted 20 common residues. each mutant measured using a peptide analog chymotrypsin digestion assay then compared wild-type FKBP12. It found site-specific interactions side chains constituting were not activity, although 37th, 55th, 82nd significantly contributed This suggests requires only hydrophobic captures Pro-containing peptide.