Irreversible inhibitors, such as the organophosphorus and organomercury compounds, cyanide, carbon monoxide and hydrogen sulphide, combine with the enzyme to form a covalent bond. 

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#XL - Q Biochemistry

Dixon plot for competitive inhibition

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#XL - Q Biochemistry

TLS Online TPP Program

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#XL - Q Biochemistry

Uncompetitive inhibitors bind only to the enzyme-substrate complex and not to the free enzyme. 

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#XL - Q Biochemistry

In neither case does the inhibitor compete with the substrate for the same binding site, so the inhibition cannot be overcome by increasing the substrate concentration.

TLS Online TPP Program

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#XL - Q Biochemistry

Substrate-binding could cause a conformational change to take place in the enzyme and reveal an inhibitor binding site, or the inhibitor could bind directly to the enzyme-bound substrate. 

TLS Online TPP Program

#Id: 8564

#XL - Q Biochemistry