Figure 1

Figure 1

Dependence of deacetylation rate on substrate concentration for two representative peptides catalyzed by HDAC6, measured using the acetate assay. The initial velocity for each substrate concentration was determined from a linear regression of a time course consisting of a minimum of three timepoints, standard error is shown. The kinetic parameters are determined from a nonlinear least square fit of the Michaelis–Menten equation to the data and are listed in Table 1. Black squares: example of data which met the criteria to produce accurate k_cat/K_M values. Green circles: example of overfit data resulting in calculation of a lower limit for k_cat/K_M, due to the K_M being lower than the detection limit of the assay.