= Competitive inhibition
{wiki}
In the model of <reversible enzyme inhibition>, <competitive inhibition> makes <substrate> binding and inhibitor binding mutually exclusive: $EI$ is allowed but $ESI$ is absent. Set $\alpha'=1$, equivalently take $K_i'\to\infty$. Then
$$
v=\frac{V_{\max}s}{\alpha K_M+s},\qquad
V_{\max,\rm app}=V_{\max},\quad K_{M,\rm app}=\alpha K_M.
$$
For the chosen $I=30\,\mathrm{\mu M}$, $\alpha=4$: the half-limiting <substrate> <concentration> rises from $20$ to $80\,\mathrm{\mu M}$, while the limiting <reaction rate> remains $100\,\mathrm{\mu M\,min^{-1}}$. At $s=200\,\mathrm{\mu M}$ the inhibited <reaction rate> is $500/7\approx71.43\,\mathrm{\mu M\,min^{-1}}$, compared with the uninhibited $1000/11\approx90.91\,\mathrm{\mu M\,min^{-1}}$. “Overcome by <substrate>” means that their ratio tends to one as $s\to\infty$, not that any finite addition removes the difference.
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