Redox-dependent hydrogen-bond network rearrangement of ferredoxin–NADP <sup>+</sup> reductase revealed by high-resolution X-ray and neutron crystallography
High-resolution X-ray and neutron crystallography were employed to elucidate redox-dependent structural changes in ferredoxin-NADP<sup>+</sup> reductase (FNR) from maize. This study focused on the rearrangement of hydrogen-bond networks upon FAD reduction. The X-ray structures of wild-type FNR in oxidized and reduced states were refined to 1.15 and 1.10 Å resolution, respectively, revealing no large structural changes in the main-chain backbones. Neutron crystallography provided complementary insights, confirming protonation at N1 and N5 of the isoalloxazine ring and visualizing hydrogen bonds that were undetectable by X-ray analysis. These findings illuminate the dynamic reorganization of water-mediated hydrogen-bond networks during redox transitions, which may underpin the redox-dependent modulation of partner binding by FNR. This integrated structural approach highlights the synergistic use of X-ray and neutron crystallography in studying redox-active proteins.
Authors
- Genji Kurisu (ORCID: https://orcid.org/0000-0002-5354-0807)
- Naomine Yano (ORCID: https://orcid.org/0000-0001-9774-6885)
- Mai Uenaka
- Katsuhiro Kusaka (ORCID: https://orcid.org/0000-0002-1664-2855)
- Jiang Yu (ORCID: https://orcid.org/0000-0002-4450-541X)
- Hideaki Tanaka (ORCID: https://orcid.org/0000-0003-2035-954X)
- Yusuke Ohnishi
- Akane Ise
Institutions
- Japan Synchrotron Radiation Research Institute (JP)
- Comprehensive Research Organization for Science and Society (JP)
- Protein Research Foundation (JP)
- The University of Osaka (JP)
Publication Details
- Journal
- Acta Crystallographica Section F Structural Biology Communications
- Published
- 2025-02-06
- DOI
- https://doi.org/10.1107/s2053230x25000524
- Citations
- 1
- Primary Topic
- Enzyme Structure and Function
- Type
- article
- Field-Weighted Citation Impact
- 0.52
Funders
- Japan Science and Technology Agency