Term: binding site
https://doi.org/10.1351/goldbook.B00649

Definition:
A specific region (or atom) in a molecular entity that is capable of entering into a stabilizing interaction with another molecular entity. An example of such an interaction is that of an active site in an enzyme with its substrate. Typical forms of interaction are by hydrogen bonding, coordination and ion pair formation. Two binding sites in different molecular entities are said to be complementary if their interaction is stabilizing.

Related Terms:
1) molecular entity (http://doi.org/10.1351/goldbook.M03986).
2) substrate (http://doi.org/10.1351/goldbook.S06083).
3) hydrogen bonding (http://doi.org/10.1351/goldbook.H02899).
4) coordination (http://doi.org/10.1351/goldbook.C01329).
5) ion pair (http://doi.org/10.1351/goldbook.I03231).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1089 (https://doi.org/10.1351/pac199466051077)

Citation: 'binding site' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.B00649

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