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Updated: Nov 21, 2025
08:48
Specificity Analysis of Protein Lysine Methyltransferases Using SPOT Peptide Arrays
Published on: November 29, 2014
14.2K
Structural basis for substrate specificity of l-methionine decarboxylase
Atsushi Okawa1, Tomoo Shiba2,3, Masaya Hayashi1
1Department of Biofunctional Chemistry, Okayama University, Okayama, Japan.
Protein Science : a Publication of the Protein Society
|January 16, 2021
Summary
l-Methionine decarboxylase (MetDC) is a vitamin B6-dependent enzyme. Crystal structures reveal key roles for Gln64 in substrate specificity and Tyr421 in catalysis during methionine decarboxylation.
Area of Science:
- Biochemistry
- Enzymology
- Structural Biology
Background:
- l-Methionine decarboxylase (MetDC) is a vitamin B6-dependent enzyme.
- It catalyzes the non-oxidative decarboxylation of l-methionine, yielding 3-methylthiopropylamine and CO2.
Purpose of the Study:
- To elucidate the structural basis of MetDC function and substrate specificity.
- To identify key residues involved in the catalytic mechanism.
Main Methods:
- X-ray crystallography was used to determine the structures of MetDC in ligand-free and intermediate states.
- Mutational and biochemical analyses were performed.
Main Results:
- Crystal structures revealed the enzyme's architecture and reaction intermediates.
- Gln64 was identified as crucial for substrate specificity.
- Tyr421 was proposed as the catalytic acid for post-decarboxylation protonation.
Conclusions:
- The study provides structural insights into MetDC mechanism and substrate recognition.
- Gln64 and Tyr421 are key players in MetDC enzymatic activity.
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