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Conformational States of Cytochrome P450 Oxidoreductase Evaluated by Forster Resonance Energy Transfer Using Ultrafast Transient Absorption Spectroscopy.

ABSTRACT: NADPH-cytochrome P450 oxidoreductase (CYPOR) was shown to undergo large conformational rearrangements in its functional cycle. Using a new Förster resonance energy transfer (FRET) approach based on femtosecond transient absorption spectroscopy (TA), we determined the donor-acceptor distance distribution in the reduced and oxidized states of CYPOR. The unmatched time resolution of TA allowed the quantitative assessment of the donor-acceptor FRET, indicating that CYPOR assumes a closed conformation in both reduced and oxidized states in the absence of the redox partner. The described ultrafast TA measurements of FRET with readily available red-infrared fluorescent labels open new opportunities for structural studies in chromophore-rich proteins and their complexes.

SUBMITTER: Kovrigina EA

PROVIDER: S-EPMC6505697 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Conformational States of Cytochrome P450 Oxidoreductase Evaluated by Förster Resonance Energy Transfer Using Ultrafast Transient Absorption Spectroscopy.

Kovrigina Elizaveta A EA Pattengale Brian B Xia Chuanwu C Galiakhmetov Azamat R AR Huang Jier J Kim Jung-Ja P JP Kovrigin Evgenii L EL

Biochemistry 20161019 43

NADPH-cytochrome P450 oxidoreductase (CYPOR) was shown to undergo large conformational rearrangements in its functional cycle. Using a new Förster resonance energy transfer (FRET) approach based on femtosecond transient absorption spectroscopy (TA), we determined the donor-acceptor distance distribution in the reduced and oxidized states of CYPOR. The unmatched time resolution of TA allowed the quantitative assessment of the donor-acceptor FRET, indicating that CYPOR assumes a closed conformatio ...[more]

PMID: 27741572

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