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Updated: Aug 14, 2026
08:25
Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)
Published on: January 17, 2020
Metal Coordination Dynamics Governs Selective Halogenation in α-KG/Fe-Dependent Halogenase SyrB2
Wenli Yuan1, Jiayong Huang2, Jia Liu3
1State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, P. R. China.
Angewandte Chemie (International Ed. in English)
|August 12, 2026
Summary
α-Ketoglutarate (α-KG)-dependent enzymes achieve selective halogenation via metal coordination dynamics. The Fe(IV)-oxo to Fe(III)-OH transformation controls C-H bond activation and chlorination, minimizing hydroxylation.
Area of Science:
- Biochemistry
- Enzymology
- Organic Chemistry
Background:
- α-Ketoglutarate (α-KG)-dependent nonheme iron enzymes are crucial for natural product biosynthesis.
- The precise mechanism of selective halogenation by α-KG/Fe-dependent halogenases versus hydroxylation is debated.
Purpose of the Study:
- To elucidate the halogenation mechanism in the SyrB2 enzyme.
- To understand how selective C-H bond activation and chlorination are achieved.
Main Methods:
- Computational investigations
- Crystallographic studies
- Mössbauer spectroscopy
- Nuclear resonance vibrational spectroscopy (NRVS)
- 2H-HYSCORE spectroscopy
- Kinetic analysis
Main Results:
- Metal coordination dynamics dictate selective C-H bond activation and chlorination in SyrB2.
- Fe(IV)-oxo species conformational changes enable hydrogen atom transfer.
- Fe(III)-OH intermediate re-isomerization promotes chlorination over hydroxylation.
Conclusions:
- The study reveals a detailed mechanism for selective halogenation by SyrB2.
- Metal coordination dynamics are key to controlling enzymatic halogenation pathways.
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