Noncovalent interactions that tune the reactivities of the flavins in bifurcating electron transferring flavoprotein.

ABSTRACT: Bifurcating electron transferring flavoproteins (Bf-ETFs) tune chemically identical flavins to two contrasting roles. To understand how, we used hybrid quantum mechanical molecular mechanical calculations to characterize noncovalent interactions applied to each flavin by the protein. Our computations replicated the differences between the reactivities of the flavins: the electron transferring flavin (^ETflavin) was calculated to stabilize anionic semiquinone (ASQ) as needed to execute its single-electron transfers, whereas the Bf flavin (^Bfflavin) was found to disfavor the ASQ state more than does free flavin and to be less susceptible to reduction. The stability of ^ETflavin ASQ was attributed in part to H-bond donation to the flavin O2 from a nearby His sid

SUBMITTER: Gonzalez-Viegas M 

PROVIDER: S-EPMC10279923 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature