Enzyme Inhibitor

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Enzyme Inhibitor

 

a chemical substance that selectively inhibits the activity of an enzyme or a group of related enzymes. Even in very low concentrations, enzyme inhibitors repress an organism’s vital physiological functions. Many toxic substances, including pesticides, such nerve gases as lewisite, and such respiratory toxins as cyanides and hydrogen sulfide, have a toxic effect owing to the inhibition of enzymes, for example, the enzyme cholinesterase in arthropods.

The study of the effect of enzyme inhibitors on enzymes or groups of enzymes facilitates the search for antidotes or for new pesticides to control harmful insects, mites and ticks, and weeds. The term “enzyme inhibitors” sometimes refers to enzymes in the poisons of snakes, bees, and scorpions that destroy tissues or blood cells in man and animals.

References in periodicals archive ?
Kinetic study of angustidine (2) on BChE suggested a mixed inhibition mode with an inhibition constant (Ki) of 6.
Relationship between the inhibition constant (K) and the concentration of inhibitor which causes 50 per cent inhibition (ISO) of an enzymatic reaction.
Meanwhile, the other inhibition parameters, including inhibition types and inhibition constant ([K.
The inhibition constant (Ki), the inhibitor concentration at which the reaction is half of the maximal rate, was obtained by a secondary plot using the slope of the primary Lineweaver-Burk Plot and fitted by V0 GraphPad Prism 4.
5-10 [micro]g/m1) competitively inhibited human and rat liver microsomal CYP1A2 activity with inhibition constant ([K.
Relationship between the inhibition constant (K1) and the concentration of inhibitor which causes 50 per cent inhibition (1C50) of an enzymatic reaction.
02 mg/ml (a) The apparent inhibition constant (Ki) of test compounds was calculated using Lineweaver-Burk plots.
6 In previous projects, after a list of computational "hits" has actually been screened in biological assays to determine inhibition constants, the percentage of compounds meeting a pre-established level of antagonistic activity in vitro has ranged between 5 and 20%.
Inhibition constants were derived from the study and discussed in relation to the propensity of the active constituents concerned to cause drug-herb interaction.
However, because of limitations in detecting possible changes in PERC and MC metabolism caused by TCE coexposure, only inhibition of TCE metabolism was implemented through the use of appropriate inhibition constants (i.