# acetyl

/ˈæsɪtˌaɪl/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/acetyl
Updated: 2026-05-30

## Definition

a chemical group that has a specific structure and is found in many living things. It is often part of larger molecules like proteins or DNA.

For teachers: a functional group consisting of a methyl group linked to a carbonyl group. It is a common substituent in organic chemistry and biochemistry, particularly in the context of acetylation reactions.

## Examples

- The enzyme adds an acetyl group to the protein.
- In biochemistry, the acetyl group is often transferred between molecules by enzymes called acetyltransferases.
- The modification of histone proteins through the addition of an acetyl group can significantly alter the accessibility of DNA to transcriptional machinery, thereby influencing gene expression.

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