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Updated: Aug 5, 2026
17:12
Profiling of Methyltransferases and Other S-adenosyl-L-homocysteine-binding Proteins by Capture Compound Mass Spectrometry (CCMS)
Published on: December 20, 2010
S-Adenosyl-L-Homocysteine Hydrolase (SAHH): Structure, Function, and Applications
Jinsha Huang1,2, Qingpu Chen2, Haihua He2
1College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China.
Biomolecules
|July 28, 2026
Summary
S-adenosyl-L-homocysteine hydrolase (SAHH) is a key enzyme in cellular methylation. Its diverse adaptations across species influence disease and offer therapeutic and biotechnological applications.
Area of Science:
- Biochemistry and Molecular Biology
- Enzymology
- Evolutionary Biology
Background:
- S-adenosyl-L-homocysteine hydrolase (SAHH) is a conserved enzyme critical for the methionine cycle, regulating cellular methylation potential.
- SAHH dysregulation is linked to various diseases, including cancer, cardiovascular, and neurodegenerative disorders.
- Understanding SAHH's structure, function, and evolution is crucial for therapeutic and biotechnological advancements.
Purpose of the Study:
- To systematically review the biological distribution, catalytic mechanisms, structural architecture, and regulation of SAHH across diverse species.
- To highlight lineage-specific adaptations that fine-tune SAHH's substrate preference, cofactor affinity, and thermostability.
- To integrate mechanistic, structural, and evolutionary perspectives to explain SAHH's functional adaptations and translational value.
Main Methods:
- Systematic literature review of SAHH across eukaryotes, bacteria, and archaea.
- Analysis of structural and mechanistic data to identify lineage-specific adaptations.
- Integration of evolutionary, mechanistic, and structural insights.
Main Results:
- SAHH exhibits diverse adaptations, including C-terminal truncation and domain insertions, affecting its properties.
- Metal ions and NAD+ modulate SAHH activity and conformational dynamics.
- Evolutionary trade-offs between catalytic efficiency and structural rigidity are observed, especially in thermophilic organisms.
Conclusions:
- SAHH's multifaceted adaptations underpin its translational value as a therapeutic target, diagnostic biomarker, and biocatalyst.
- A unified framework integrating diverse perspectives guides the development of SAHH-targeted inhibitors, diagnostics, and engineered biocatalysts.
- These advancements have broad applications in precision medicine and biotechnology.
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