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Updated: Jun 27, 2026
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Sequence-specific Labeling of Nucleic Acids and Proteins with Methyltransferases and Cofactor Analogues
Published on: November 22, 2014
Cobalamin-dependent and cobamide-dependent methyltransferases
Rowena G Matthews1, Markos Koutmos, Supratim Datta
1Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109-2216, USA. rmatthew@umich.edu
Current Opinion in Structural Biology
|December 9, 2008
Summary
Methyltransferases using cobalamin cofactors are crucial for energy generation and methionine synthesis. Complex conformational changes in these enzymes are essential for their catalytic cycle involving labile intermediates.
Area of Science:
- Biochemistry
- Enzymology
- Bioenergetics
Background:
- Methyltransferases utilizing cobalamin (or cobamides) are key enzymes in biological methyl transfer.
- These enzymes are vital for energy generation in anaerobic organisms and homocysteine to methionine conversion in diverse life forms.
Purpose of the Study:
- To elucidate the complex conformational changes in methyltransferases during catalysis.
- To understand the strategies employed by these enzymes to facilitate and control these dynamic structural rearrangements.
Main Methods:
- Spectroscopic studies
- Structural biology analyses
- Enzyme kinetics
Main Results:
- Identified specific conformational changes essential for the catalytic cycle of cobalamin-dependent methyltransferases.
- Revealed the role of cobalt coordination and intermediate lability in driving these structural dynamics.
Conclusions:
- Complex conformational changes are integral to the function of methyltransferases.
- Understanding these dynamics provides insights into enzyme mechanisms and potential therapeutic targets.
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