TABLE 2

Comparison of the median-effect equation and the Hill equation

Median-Effect Equationa Hill Equation and Michaelis-Menten Equationb
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log[(fa)-1 - 1[-1 = m log D - m log Dm log][v/(Vmax - v) = n log S - log K
when m = 1: fa = 1[1 + Dm/D)] when n = 1: v/Vmax = 1[1 + (Km/S)]

  • ↵ a Features: 1) inhibitor-oriented; 2) for ligand effect; 3) easily expandable to two or more inhibitors; 4) derived by mathematical induction and deduction

  • ↵ b Features: 1) substrate-oriented; 2) for substrate saturation; 3) difficult to expand to two or more substrates; 4) derived by phenomenal observation and reasoning