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Related Experiment Video

Updated: Jul 16, 2026

Sequence-specific Labeling of Nucleic Acids and Proteins with Methyltransferases and Cofactor Analogues

Sequence-specific Labeling of Nucleic Acids and Proteins with Methyltransferases and Cofactor Analogues

Published on: November 22, 2014

S-adenosylmethionine and its products.

M A Grillo¹, S Colombatto

¹Dipartimento di Medicina e Oncologia Sperimentale, Sezione di Biochimica, Università di Torino, Torino, Italy. Mariaangelica.grillo@unito.it

|March 6, 2007

Summary

S-adenosylmethionine (SAM) is crucial for methylation, polyamine synthesis, and radical catalysis. Its byproducts, like homocysteine and methylthioadenosine, are efficiently recycled, highlighting metabolic adaptability.

Area of Science:

Biochemistry
Metabolic pathways
Enzymology

Background:

S-adenosylmethionine (SAM) is a key biological methyl donor.
SAM participates in diverse cellular processes including methylation, polyamine synthesis, and radical-based catalysis.
The synthesis of SAM involves specifically regulated enzyme forms.

Purpose of the Study:

To elucidate the metabolic fate and reutilization of S-adenosylmethionine and its byproducts.
To understand the enzymatic regulation in SAM synthesis.
To map the recycling pathways of SAM's downstream compounds.

Main Methods:

Enzymatic assays to study SAM synthesis.
Metabolic tracing to track byproduct utilization.
Biochemical analysis of homocysteine and methylthioadenosine pathways.

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Published on: December 20, 2010

In Vitro Assay to Measure Phosphatidylethanolamine Methyltransferase Activity

In Vitro Assay to Measure Phosphatidylethanolamine Methyltransferase Activity

Published on: January 5, 2016

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Last Updated: Jul 16, 2026

Sequence-specific Labeling of Nucleic Acids and Proteins with Methyltransferases and Cofactor Analogues

Sequence-specific Labeling of Nucleic Acids and Proteins with Methyltransferases and Cofactor Analogues

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Profiling of Methyltransferases and Other S-adenosyl-L-homocysteine-binding Proteins by Capture Compound Mass Spectrometry (CCMS)

Profiling of Methyltransferases and Other S-adenosyl-_L-homocysteine-binding Proteins by Capture Compound Mass Spectrometry (CCMS)

Published on: December 20, 2010

In Vitro Assay to Measure Phosphatidylethanolamine Methyltransferase Activity

In Vitro Assay to Measure Phosphatidylethanolamine Methyltransferase Activity

Published on: January 5, 2016

Main Results:

SAM is synthesized via catalysis of differentially regulated enzyme forms.
Methylation byproducts like homocysteine are remethylated, converted to cysteine, or released.
Products from polyamine synthesis and radical catalysis, such as methylthioadenosine and 5-deoxyadenosine, are cleaved and reutilized.

Conclusions:

The metabolic network efficiently recycles SAM and its byproducts, ensuring cellular resource conservation.
Diverse enzymatic pathways contribute to the regulation and utilization of SAM.
The reutilization of SAM's end products demonstrates significant metabolic flexibility and efficiency.