enzyme inhibition

Also found in: Medical.

Enzyme inhibition

The prevention of an enzymic process as a result of the interaction of some substance with an enzyme so as to decrease the rate of the enzymic reaction. The substance causing such an effect is termed an inhibitor. Enzyme inhibitors are important as chemotherapeutic agents, as regulators in normal control of enzymic processes in living organisms, and as useful agents in the study of biochemistry. See Antibiotic, Chemotherapy, Enzyme

Inhibitors have been classified as competitive, noncompetitive, and uncompetitive. The effect of a competitive inhibitor is to bind only free enzyme. This can be reversed by sufficiently increased substrate concentrations, so that essentially all of the enzyme is bound into an enzyme-substrate complex. Since both noncompetitive and uncompetitive inhibitors interact with the enzyme-substrate complex, their effects are not nullified by increased concentrations of substrate. An uncompetitive inhibitor exerts less effect (as percent of control) at low than at high substrate concentrations, since less of the enzyme is in the form of the enzyme-substrate complex, with which it interacts. A noncompetitive inhibitor, which reacts with both free enzyme and the enzyme-substrate complex, exerts comparable effects at all substrate concentrations.

enzyme inhibition

[′en‚zīm ‚in·ə·′bish·ən]
Prevention of an enzymic process as a result of the interaction of some substance with the enzyme so as to decrease the rate of reaction.
References in periodicals archive ?
Is tissue converting enzyme inhibition a determinant of the antihypertensive efficacy of converting enzyme inhibitors?
The Galileo LIMS system is designed to conduct permeability, enzyme inhibition (IC50 and Ki) assays, metabolic stability and profiling, and protein binding experiments in a GLP and 21 CFR Part 11 compliant manner.
Unlike conventional agents that kill diseased cells by enzyme inhibition -- with toxic effects and drug resistance, ECTA provides a "Trojan Horse Solution" to this problem with powerful drugs that carry a potent toxin hidden within their chemical structure.
Development of this series of ACC inhibitors has yielded deep structure-activity relationships, sub-nanomolar enzyme inhibition, functional activity in cellular assays and favorable drug-like properties leading to in vivo proof of concept.
Examples of technologies specifically designed to solve these problems that are covered in the report include natural transporter systems, enzyme inhibition, and bioadhesion.
Ethanol was somewhat better but caused enzyme inhibition when present in the assay mixture at >20% by volume, thus limiting the range of the assay.
The MtFabI and EcFabI enzyme inhibition assays were performed as previously described (Tasdemir et al.
The Prevention of Events With Angiotensin Converting Enzyme Inhibition trial has been widely misinterpreted, to the detriment of patient care.
Furthermore, the specificity of the enzyme inhibition of several of these compounds is poor, both with respect to fungal versus nonfungal sterol 14[alpha]-demethylases and versus other P450 enzymes including aromatase.
Its emphasis on enzyme inhibition will also make it attractive to pharmacologists and pharmaceutical chemists interested in rational drug design.