What are non-competitive inhibitors?

Explanation

Competitive Inhibitor: Molecules that resemble the shape of the substrate and may compete to occupy the active site of enzyme are known as competitive inhibitors. For example : the enzyme that catalyses the reaction between carbon dioxide and the `CO_(2)` acceptor molecule in photosynthesis, known as ribulose biphosphate carboxylase oxygenase (RUBISCO) is competitively inhibited by oxygen/carbon-di-oxide in the chloroplast. the competitive inhibitor is malonate for succinic dehydrogenase.

Non-competitive Inhibitors: There are certain inhibitors which may unlike the substrate molecule but still combines with the enzyme. this either blocks the attachment of the substrate to active site or change the shape so that it is unable to accept the substrate. for example the effect of the amino acids alanine on the enzyme pyruvate kinase in the final step of glycolysis. Certain non-reversible/irreversible inhibitors bind tightly and permanently to an enzyme and destroy its catalytic properties entirely. these could also be termed as poisons. example-cyanide ions which blocks cytochrome oxidase in terminal oxidation in cell aerobic respiration, the nerve gas sarin blocks a neurotransmitter in synapse transmission.