Question

What is competitive and uncompetitive reversible inhibition? And how are they similar? and most importantly, how is their effect on rate at which is can transform a substrate different?

Answer 1

A competitive inhibitor competes with the substrate for the active site of an enzyme, but a reaction usually does not occur once the inhibitor (I) is bound. While the inhibitor occupies the active site it prevents binding by the substrate.

Competitive inhibitors are often compounds that look like the substrate and combine with the enzyme to form an EI complex. This type of inhibition can be analyzed quantitatively by steady-state kinetics .

Because the inhibitor drags reversibly to the enzyme, the competition can be inclined to favor the substrate simply by adding more substrate. Competitive inhibition is used therapeutically to treat patients who have ingested methanol, a solvent found in gas-line antifreeze.

Methanol is converted to formaldehyde by the action of the enzyme alcohol dehydrogenase. Formaldehyde damages many tissues, and blindness is a common result because the eyes are particularly sensitive.

An uncompetitive inhibitor also binds at a site distinct from the substrate. However, an uncompetitive inhibitor will bind only to the ES complex. (The noncompetitive inhibitor binds to either free enzyme or the ES complex.

They are similar in that, in which they have different binding site, if they start to fill each other, then the rate starts to get lower, since there is lower bingind sites for reaction

Competitive and uncompetitive inhibations will "fight" and search for more possible binding sites

They differ mainly on:

the rate of reaction, in competititve inhibition, substrates will have lower rates, since they are "competing" between each other, a binded site will not work for both species.

In the other hand, the resversible inhibition helps in that in which the enzymes will simply follow a direct proportional rate of reaciton for both species.