Calculate the initial enzyme rate from Vmax, Km, and substrate concentration.
| v | – |
Use this calculator in enzyme kinetics when you have Vmax and Km from a Lineweaver–Burk plot or a fit, plus a substrate concentration, and you want v.
The calculation is v = Vmax × [S] / (Km + [S]). Use the same concentration unit for Km and [S]; v then has the same unit as Vmax. At [S] = Km the rate is Vmax/2.
This is the uninhibited hyperbolic form. It does not include competitive or mixed inhibition, cooperativity, or a progress-curve integration.
Vmax: Maximum rate in your assay unit, for example µmol/min or AU/s.
Km: Michaelis constant in concentration units, for example 0.05 mM.
[S]: Substrate concentration in the same unit as Km.
v: Initial rate in the same unit as Vmax.
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