methylase

enzyme

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June 30, 2026

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Methylase is an enzyme that catalyzes methylation, which is the transfer of a methyl group to an organic compound. This process is crucial in biological systems, particularly in DNA and protein methylation.12

In DNA, methylase enzymes add methyl groups to bases like cytosine or adenine. This modification, known as DNA methylation, plays a vital role in regulating gene expression, controlling embryonic development, and protecting DNA from degradation by restriction enzymes in bacteria. In higher eukaryotes, DNA methylation can prevent transcription and is involved in processes like imprinting.32

Protein methylation involves adding methyl groups to amino acids like lysine or arginine within proteins. This modification also influences gene expression by activating or deactivating genes. Methylation is essential for embryonic development, and errors in this process can contribute to tumor formation.2

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restriction enzyme
Enzymes called methylases add methyl groups (—CH₃) to adenine or cytosine bases within the recognition sequence, which is thus modified and protected from the endonuclease. The restriction enzyme and its corresponding methylase constitute the restriction-modification system of a bacterial species.
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Enzymes called methylases add methyl groups (—CH₃) to adenine or cytosine bases within the recognition sequence, which is thus modified and protected from the endonuclease. The restriction enzyme and its corresponding methylase constitute the restriction-modification system of a bacterial species.
Read More