What's new in enzymatic halogenations.
Danica Galonić Fujimori1, Christopher T Walsh
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
Current Opinion in Chemical Biology
|September 21, 2007
Summary
Enzymatic halogenation in natural products is more diverse than previously thought, involving halide ions, atoms, and X+ equivalents. New research reveals tailored mechanisms and coenzyme needs for these diverse halogenation processes.
Area of Science:
- Biochemistry
- Organic Chemistry
- Molecular Biology
Background:
- Halogenation is crucial for natural product function.
- Haloperoxidases were the established mechanism for enzymatic halogenation.
- Recent advances offer new perspectives on halogen incorporation.
Purpose of the Study:
- To explore the diverse mechanisms of enzymatic halogenation.
- To understand the role of different oxidation states of halogens in biosynthesis.
- To investigate the substrate-specific enzyme requirements.
Main Methods:
- Microbial genome sequencing
- Enzymatic studies
- Structural biology
Main Results:
- Identified enzymatic transfer of halide equivalents in three oxidation states: halide ions (X-), halogen atoms (X*), and X+ equivalents.
- Demonstrated that halogen incorporation mechanisms are tailored to specific substrates.
- Revealed distinct redox coenzyme requirements for different halogenation pathways.
Conclusions:
- Enzymatic halogenation encompasses a broader range of mechanisms than previously recognized.
- Understanding these diverse pathways is key to natural product biosynthesis.
- Tailored enzymatic strategies and coenzyme usage are central to halogen incorporation.
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