active site


Definition of active site

: a region on the surface of an enzyme whose shape permits binding only of a specific molecular substrate that then undergoes catalysis

Examples of active site in a Sentence

Recent Examples on the Web Each enzyme has an active site, which is where the reaction takes place. Svenja Lohner, Scientific American, 10 Nov. 2016 Highlights of the still-active site include a 2011 warning to the entertainment industry about Apple TV and a decade-early defense of non-fungible tokens (NFTs). Alex Konrad, Forbes, 12 Apr. 2022 Many drugs are designed to fit into this active site, which can keep a protein from working. John Timmer, Ars Technica, 25 Mar. 2022 Errors affecting the enzyme’s active site that binds to drugs, however, can cripple its ability to break down a drug and subsequently mean there’s more of the drug circulating in the blood. C. Michael White, The Conversation, 4 Oct. 2021 There are multiple investigations still going on at the active site. Mariah Rush,, 2 July 2021 Subsequent studies report three drugs, boceprevir, narlaprevir, and telaprevir, inhibit NSP5 protease proteolytic activity and bind into its active site. William A. Haseltine, Forbes, 4 June 2021 While the active site of the NSP3 protease does not have much structural similarity with the HCV or NSP5 proteases, the researchers carried out virtual docking studies of these same 10 HCV drugs into the substrate-binding cleft of NSP3 protease. William A. Haseltine, Forbes, 4 June 2021 As the chain gets progressively longer, its ability to fit into the active site of the enzymes gradually gets worse. John Timmer, Ars Technica, 20 Jan. 2020 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'active site.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of active site

1957, in the meaning defined above

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Time Traveler for active site

Time Traveler

The first known use of active site was in 1957

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Dictionary Entries Near active site

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active site

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Statistics for active site

Last Updated

8 May 2022

Cite this Entry

“Active site.” Dictionary, Merriam-Webster, Accessed 16 May. 2022.

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More Definitions for active site

active site


Medical Definition of active site

: a region especially of a biologically active protein (as an enzyme) where catalytic activity takes place and whose shape permits the binding only of a specific reactant molecule

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