Kinetics of product formation of BLV-PR.

(A) Progress curves for a representative experiment. The enzyme (5 nM, final concentration after 4-fold dilution) was added to reaction mixtures containing CA-NC substrate (5 μM) in buffer reaction, at 37°C. The black trace represents the best fit of Eq 2, from which the exponential rate constant k_obs was obtained. The inset shows the progress curve when 5 μl of concentrated PR (2.5 μM) were added to 195 μl reaction mixtures containing the CA-NC substrate (20 μM) in the same buffer as in (A). (B) Dependence of k_obs on the concentration of the CA-NC substrate (1–50 μM). The data points represent measurements in a representative experiment. The black trace represents the best fit of Eq 3 in agreement with Scheme 2.