Direct observation of a deoxyadenosyl radical in an active enzyme environment

Heidinger, Lorenz; Kneuttinger, Andrea C.; Kashiwazaki, Gengo; Weber, Stefan; Carell, Thomas und Schleicher, Erik (2016): Direct observation of a deoxyadenosyl radical in an active enzyme environment. In: Febs Letters, Bd. 590, Nr. 24: S. 4489-4494

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.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Chemie und Pharmazie > Department Chemie
• Themengebiete: 500 Naturwissenschaften und Mathematik > 540 Chemie
• ISSN: 0014-5793
• Sprache: Englisch