Question

An example of non-competitive inhibition is

• A. The inhibition of succinic dehydrogenase by malonate
• B. Cyanide action on cytochrome oxidase
• C. Sulpha drug on folic acid synthesizing bacteria
• D. The inhibition of hexokinase by glucose 6-phosphate
• E. Both B and D

Answer 1

The correct option is B Cyanide action on cytochrome oxidase

In non-competitive inhibition, the inhibitor binds to enzyme at a place other than substrate binding site. It results in destruction of enzyme activity. The substrate may combine with such an enzyme but product formation is inhibited. For example, cyanide inhibits cytochrome oxidase activity by combining irreversibly with copper of cytochrome oxidase.