Figure 4.

CPMG analysis of the Met63 resonance in [¹³CH₃-Met]RT(I63M). Measurements were made on (a) 50 μM [¹³CH₃-Met]RT(I63M) in the NMR buffer at 25°C or (b) 50 μM [¹³CH₃-Met]RT(I63M) plus 200 μM NVP and lacking the Mg²⁺ in the buffer. The first data point cannot be meaningfully analyzed within the context of the other parameter restraints. Other than the Mg²⁺ concentration, the sample buffer is the same as described in Fig. 2. All measurements were made at 18.8 T.