Michaelis-Menten equation

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Michaelis-Menten Kinetics: Enzyme Behavior

v = \frac{V_{max}[S]}{K_m + [S]} Latex

Variable Definition & Clinical Significance
$V_{max}$ Maximum reaction rate at enzyme saturation. Proportional to total enzyme concentration $[E]_t$.
$K_m$ Substrate concentration at $1/2 V_{max}$. Represents inversely the affinity of the enzyme for substrate (Low $K_m$ = High Affinity) inversely.
$[S]$ Substrate concentration.
High-Yield Core Realities:

  • Lineweaver-Burk Plot: A double-reciprocal plot ($1/v$ vs $1/[S]$). Used to visualize inhibition:
    • Competitive Inhibition: Increases $K_m$ (shifts x-intercept), $V_{max}$ is unchanged (y-intercept same).
    • Noncompetitive Inhibition: $K_m$ is unchanged, decreases $V_{max}$ (shifts y-intercept higher).
  • Zero vs. First Order: At low $[S]$, kinetics are first-order (rate depends on $[S]$). At high $[S]$ ($[S] \gg K_m$), kinetics become zero-order (rate is independent of $[S]$, velocity reaches $V_{max}$).