FIGURE 5.

Reaction of wt β2, CDP, ATP and (A) Y₄₁₃NH₂Y-α2 or (B) Y₇₃₁F/Y₄₁₃NH₂Y-α2 monitored by SF UV-vis spectroscopy. The reaction was monitored for an increase at 325 nm (λ_max of NH₂Y₄₁₃•) and a decrease at 410 nm (λ_max of Y₁₂₂•). The reaction with Y₄₁₃NH₂Y-α2 (A) was complete within 2 seconds. The reaction with Y₇₃₁F/Y₄₁₃NH₂Y-α2 was monitored over 200 s (B), with the first 30 s expanded in the inset. Exponential fits to the data are indicated by solid black lines.