Table I.

Kinetic and equilibrium constants of control and R286L ACC synthase

EnzymeKm SAMkcatkcat/Km SAMKD PLP
25°C35°C
mm s−1 m−1s−1 μm
Control (del-1)0.121-a 9.798.15 × 104 0.531-b 0.631-b
R286L0.751-a 8.20 × 10−3 1.09 × 101.08 × 101-b 1.61 × 101-b
Control/R286L0.161.20 × 103 7.49 × 103 4.9 × 10−2 3.9 × 10−2
  • F1-a Kinetic data were collected at pH 9.5 with a fixed PLP concentration of 500 μm and a variable AdoMet concentration from 20 to 2,000 μm.

  • F1-b The dissociation constants for the ACC synthase-PLP complex were determined based on data obtained from the fluorescence spectroscopic measurements at pH 7.5.