Lineweaver-Burk Plot Calculator
Compute Michaelis-Menten kinetic constants (Km and Vmax) from substrate-velocity data points using a double-reciprocal linear regression model.
Experimental Data Pairs
Input substrate concentration [S] and initial velocity v for 5 data points.
Maximum Velocity (V_max)
Michaelis Constant (K_m)
Linear Fit Quality (R²)
Enzyme Inhibition Diagnostics
Competitive inhibitors increase slope (Km increases, Vmax unchanged). Non-competitive inhibitors change y-intercept (Vmax decreases, Km unchanged).
Enzyme Inhibition Effects on Lineweaver-Burk Parameters Reference
| Inhibition Mode | Effect on Vmax | Effect on Km | Lineweaver-Burk Graph Pattern |
|---|---|---|---|
| Competitive Inhibition | Unchanged | Increases (Km' > Km) | Lines intersect at Y-axis (1/Vmax) |
| Pure Non-Competitive Inhibition | Decreases (Vmax' < Vmax) | Unchanged | Lines intersect at X-axis (-1/Km) |
| Uncompetitive Inhibition | Decreases (Vmax' < Vmax) | Decreases (Km' < Km) | Parallel lines (slope m = Km/Vmax constant) |
Calculation Methodology & Equations
Double-Reciprocal Transformation
Linear regression ($y = mx + c$) is applied to $y = 1/v$ and $x = 1/[S]$.
Solving Km and Vmax
$c$ represents the Y-intercept ($1/V_$) and $m$ represents the line slope ($K_m / V_$).
Frequently Asked Questions
What is a Lineweaver-Burk Plot? ▼
A Lineweaver-Burk plot (or double-reciprocal plot) graphs 1/v on the y-axis versus 1/[S] on the x-axis. It transforms the hyperbolic Michaelis-Menten curve into a straight line ($y = mx + c$).
How do you extt Km and Vmax from the plot slope and intercepts? ▼
1/Vmax is equal to the y-intercept ($c$), so $V_{} = 1/c$. The x-intercept is $-1/K_m$, and the slope ($m$) is equal to $K_m / V_{}$, so $K_m = m times V_{}$.
What are the limitations of a Lineweaver-Burk plot? ▼
Double-reciprocal transformations distort error structures: small experimental errors at low substrate concentrations (high 1/[S] values) are disproportionately magnified in linear regression.
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