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A 55-year-old man with alcoholism is brought to the ...

Competitive inhibitor

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submitted by m-ice(124),

Competitive inhibitors increase the Km of the substrate. The Km represents how easily a substrate can bind the active site, with a lower Km representing easy binding, and a higher Km meaning more difficult. If you add a competitive inhibitor, like ethanol in this case, it makes it more difficult for the methanol to bind the active site, because it must compete with the ethanol.

deathbystep1  but how is ethanol a "inhibitor" of alcohol dehydrogenase? isnt the concept that both ethanol and methanol compete for the same binding site of alcohol dehydrogenase and hence ethanol displaces methanol preventing its metabolism? if ethanol were to be a inhibitor it would have to shut off the enzyme, which is does not. +  
krewfoo99  @deathbystep1 Competitive inhibitor simply means increasing concentration of a particular substrate will allow more binding of the substrate to the enzyme. Thus the substrate with the higher concentration will competitive inhibit the other substrate by binding to the enzyme. It dosent necessarily shut off the enzyme +  

 +0  upvote downvote
submitted by mcl(216),

lolol so instead of using fomepizole they just gonna get him real drunk

johnson  yep - supposedly, ethanol is used when a hospital/facility doesn't have fomepizole. +