9KKC

Neutron structure of Ferredoxin-NADP+ reductase from maize root -Oxidized form

Summary for 9KKC

• Entry DOI: 10.2210/pdb9kkc/pdb
• Descriptor: Ferredoxin--NADP reductase, chloroplastic, FLAVIN-ADENINE DINUCLEOTIDE, 2-(N-MORPHOLINO)-ETHANESULFONIC ACID, ... (4 entities in total)
• Functional Keywords: electron transfer, flavoprotein, oxidoreductase
• Biological source: Zea mays
• Total number of polymer chains: 1
• Total formula weight: 35584.98

Authors

Uenaka, M.,Ohnishi, Y.,Tanaka, H.,Kurisu, G. (deposition date: 2024-11-13, release date: 2025-01-29, Last modification date: 2025-03-12)

Primary citation

Uenaka, M.,Ohnishi, Y.,Ise, A.,Yu, J.,Yano, N.,Kusaka, K.,Tanaka, H.,Kurisu, G.
Redox-dependent hydrogen-bond network rearrangement of ferredoxin-NADP + reductase revealed by high-resolution X-ray and neutron crystallography.
Acta Crystallogr.,Sect.F, 81:73-84, 2025

PubMed Abstract: High-resolution X-ray and neutron crystallography were employed to elucidate redox-dependent structural changes in ferredoxin-NADP 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.

PubMed: 39913263
DOI: 10.1107/S2053230X25000524

Experimental method

NEUTRON DIFFRACTION (1.8 Å)