Figure 4
Catalysis of the cis/trans isomerization of Myb1104–111 peptide by TvCyP1. (a) Selected region of the 300-ms mixing-time ROESY spectrum of Myb1104–111 peptide (4.4 mM). The positive peaks are colored in blue and negative peaks in red. The 1H resonances of G106, P107 and K108 are marked, and the resonances from cis and trans conformers are labeled as C and T respectively. The negative cross-peaks between neighboring hydrogens are shown in red and connected by red dashed lines. (b) Exchange between cis and trans conformations was accelerated in the presence of 22 μM TvCyP1, as evidenced by the appearance of positive exchange cross-peaks between cis and trans resonances shown in blue and connected by black dashed lines. (c) Inhibition of TvCyP1 isomerase activity by CsA (22 μM) resulted in a loss of the exchange cross-peaks between cis and trans resonances.
