Editing Allosteric regulation (section)

== Allosteric modulation ==
{{Main|Allosteric modulator}}
[[Allosteric modulation]] is used to alter the activity of molecules and enzymes in biochemistry and pharmacology. For comparison, a typical drug is made to bind to the active site of an enzyme which thus prohibits binding of a substrate to that enzyme causing a decrease in enzyme activity. Allosteric modulation occurs when an [[Effector (biology)|effector]] binds to an allosteric site (also known as a regulatory site) of an enzyme and alters the enzyme activity. Allosteric modulators are designed to fit the allosteric site to cause a conformational change of the enzyme, in particular a change in the shape of the active site, which then causes a change in its activity. In contrast to typical drugs, modulators are not [[Competitive inhibition|competitive inhibitors]]. They can be positive (activating) causing an increase of the enzyme activity or negative (inhibiting) causing a decrease of the enzyme activity. The use of allosteric modulation allows the control of the effects of specific enzyme activities; as a result, allosteric modulators are very effective in pharmacology.<ref>{{cite journal | vauthors = Abdel-Magid AF | title = Allosteric modulators: an emerging concept in drug discovery | journal = ACS Medicinal Chemistry Letters | volume = 6 | issue = 2 | pages = 104–7 | date = February 2015 | pmid = 25699154 | pmc = 4329591 | doi = 10.1021/ml5005365 }}</ref> In a biological system, allosteric modulation can be difficult to distinguish from modulation by [[substrate presentation]].