pH dependence of the activity of acyl-CoA dehydrogenases in taurine buffer. Conditions: [taurine] = 47 mM, [C8-CoA] = 100 µM, [C12-CoA] = 35 µM, [C4-CoA] = 100 µM at 37°C (substrate concentrations are ≥5•Km). Enzyme concentration in the assays was 60 nM. Enzyme activities were estimated using the ferricenium assay  and are normalised for the sake of comparison. The activities values (turnover) extrapolated to low and high pH are 560 and 3800 min-1 for MCAD; 85 and 2400 min-1 for LCAD and 160 and 2050 min-1 for SCAD respectively. The pK values are derived from the curve fits. The data points are the average of 3-4 individual measurements and the vertical bars indicate the scatter where appropriate.