The enzyme -methylaspartase catalyzes the deamination of -methylaspartate [V. Williams and J. Selbin, J. Biol. Chem. 239,

Question:

The enzyme β-methylaspartase catalyzes the deamination of β-methylaspartate CH, NH T T CH3 OOC-CH-CH-COO0OC-CH-CH-COO + NH mesaconate absorbs at 240 nm

[V. Williams and J. Selbin, J. Biol. Chem. 239, 1636 (1964)]. The rate of the reaction was determined by monitoring the absorbance of the product at 240 nm (A₂₄₀). From the data in the following table, determine KM for the reaction. How does the method of calculation differ from that in Questions 26 and 27? Substrate Concentration (mmol L-) Velocity (AA240 min-) 0.002 0.045 0.005 0.115 0.020 0.285 0.040 0.380 0.060