Structural and Functional Characterization of a Novel Family of Cyclophilins, the AquaCyps
Fig 3
PPIase activities of AquaCyp293 and AquaCyp300.
(A) Kinetics of cis/trans isomerization of 3 μM Abz-Ala-Ala-Pro-Phe-pNa followed by fluorescence at 416 nm, without enzyme (black), with 8 nM (blue), 12 nM (green), 16 nM (dark blue) and 20 nM (red) AquaCyp293. (B) Refolding kinetics of RCM-T1 in the presence of increasing concentrations of AquaCyp293, 0 nM (black), 10 nM (blue), 300 nM (green) and 750 nM (red). The kinetics of refolding of 0.1 μM RCM-T1 in 0.1 M Tris/HCl pH 8.0; 2 M NaCl were measured at 15°C in the presence of various concentrations of AquaCyp293. (C, D) Catalytic efficiencies of AquaCyp293 (○) and AquaCyp300 (□) for (C) the cis/trans isomerization of Abz-Ala-Ala-Pro-Phe-pNA and (D) the refolding of RCM-T1. The measured proline-limited refolding rate constants kapp are shown as a function of the PPIase concentration. The kcat/Km values derived from the slopes are given in Table 1.
