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Spin Densities in Flavin Analogs within a Flavoprotein.

ABSTRACT: Characterization by electron paramagnetic resonance techniques of several variants of Anabaena flavodoxin, where the naturally occurring FMN cofactor is substituted by different analogs, makes it possible to improve the details of the spin distribution map in the isoallosazine ring in its semiquinone state. The analyzed variants were selected to monitor the effects of intrinsic changes in the flavin ring electronic structure, as well as perturbations in the apoflavodoxin-flavin interaction, on the spin populations. When these effects were analyzed together with the functional properties of the different flavodoxin variants, a relationship between spin population and biochemical parameters, as the reduction potential, could be envisaged.

SUBMITTER: Martinez JI

PROVIDER: S-EPMC4744158 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Spin Densities in Flavin Analogs within a Flavoprotein.

Martínez Jesús Ignacio JI Frago Susana S Lans Isaías I Alonso Pablo Javier PJ García-Rubio Inés I Medina Milagros M

Biophysical journal 20160201 3

Characterization by electron paramagnetic resonance techniques of several variants of Anabaena flavodoxin, where the naturally occurring FMN cofactor is substituted by different analogs, makes it possible to improve the details of the spin distribution map in the isoallosazine ring in its semiquinone state. The analyzed variants were selected to monitor the effects of intrinsic changes in the flavin ring electronic structure, as well as perturbations in the apoflavodoxin-flavin interaction, on t ...[more]

PMID: 26840722

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