Abstract
5'-deoxyadenosyl radicals have been proposed as the first common intermediate in the molecular reaction mechanism of the family of radical S-adenosyl-L-methionine (SAM) enzymes. However, this radical species has not yet been directly observed in a catalytically active enzyme environment. In a reduced and SAM-containing C140A mutant of the spore photoproduct lyase from Geobacillus thermodenitrificans, a mutant with altered catalytic activity, we were able to identify an organic radical with pronounced hyperfine structure using electron paramagnetic resonance spectroscopy. Guided by quantum-chemical computations at the density functional theory level of theory, this radical could be tentatively assigned to a deoxyadenosyl radical, which provides first experimental evidence for this intermediate in the reaction mechanism of radical SAM enzymes.
Item Type: | Journal article |
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Faculties: | Chemistry and Pharmacy > Department of Chemistry |
Subjects: | 500 Science > 540 Chemistry |
ISSN: | 0014-5793 |
Language: | English |
Item ID: | 48197 |
Date Deposited: | 27. Apr 2018, 08:14 |
Last Modified: | 04. Nov 2020, 13:25 |