Enzyme, a large molecule (usually either a protein or made from nucleic acids) that catalyses (speeds up) a biochemical reaction, even though it not modified in any way by the biochemical reaction it catalyses. Enzymes catalyse chemical reactions by binding to the substrate in a manner that favours the chemical reaction they catalyse over no reaction.
Enzyme inhibition basically the process by which the activity of an enzyme is reduced, it can be: competitive, non-competitive, epigenetic and uncompetitive.
Competitive inhibitors inhibit the enzyme’s activity by competing for the enzyme’s active site, which is where it catalyses the various biochemical reactions it acts on.
Uncompetitive inhibitors are substances that only bind to the enzyme when it is in the process of catalysing a biochemical process and this binding is not the active site, but rather a different site that reduces the catalytic efficiency of the enzyme.
Non-competitive inhibitors are a lot like the uncompetitive inhibitors, but unlike them they have no preference for the enzyme while it is catalysing the biochemical reaction or prior to when it is bound by the substrate.
Epigenetic inhibitors work by reducing the levels of the enzyme in the body.
Inducers increase enzyme activity usually be increasing the production of their respective enzyme(s).