S-adenosyl methionine
Quick Summary
S-adenosylmethionine (SAM) is a crucial molecule involved in biological methylation, the process of transferring a methyl group (-CH3) to other compounds. This process is vital for controlling gene expression, as seen in DNA and protein methylation.12
In biological systems, SAM acts as the primary methyl group donor. For instance, it is used by enzymes to methylate histones, which are proteins that package DNA. This methylation can either activate or deactivate genes.1
Methylation also plays a role in embryonic development, and its failure can be fatal. Furthermore, abnormal methylation patterns are linked to tumor formation, contributing to genetic instability. Bacteria also utilize methylation for self-defense, protecting their own DNA from destructive enzymes.1
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