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Model systems for flavoenzyme activity: relationships between cofactor structure, binding and redox properties.

Yves-Marie Legrand·Mark Gray·Graeme Cooke·Vincent M Rotello
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Abstract

A series of flavins were synthesized bearing electron-withdrawing and -donating substituents. The electrochemical properties of these flavins in a nonpolar solvent were determined. The recognition of these flavins by a diamidopyridine (DAP) receptor and the effect this receptor has on flavin redox potential was also quantified. It was found that the DAP-flavin binding affinity and the reduction potentials (E(1/2)) for both the DAP-bound and unbound flavins correlated well with functions derived from linear free energy relationships (LFERs). These results provide insight and predictive capability for the interplay of electronics and redox state-specific interactions for both abiotic and enzymatic systems.

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ElectrochemistryFlavinsKineticsOxidation-ReductionPyridinesThermodynamicsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Yves-Marie Legrand, Mark Gray, Graeme Cooke, Vincent M Rotello. 2003-12-24. Model systems for flavoenzyme activity: relationships between cofactor structure, binding and redox properties.. https://doi.org/10.1021/ja036940b

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