6RNW

The crystal structure of Thermosynechococcus elongatus protochlorophyllide oxidoreductase (POR) in complex with NADP.

6RNW の概要

• エントリーDOI: 10.2210/pdb6rnw/pdb
• 分子名称: NADPH-protochlorophyllide oxidoreductase, NADP NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE (3 entities in total)
• 機能のキーワード: light dependent, photosynthesis
• 由来する生物種: Thermosynechococcus elongatus
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 39981.58

構造登録者

Levy, C.W. (登録日: 2019-05-09, 公開日: 2019-10-30, 最終更新日: 2024-01-24)

主引用文献

Zhang, S.,Heyes, D.J.,Feng, L.,Sun, W.,Johannissen, L.O.,Liu, H.,Levy, C.W.,Li, X.,Yang, J.,Yu, X.,Lin, M.,Hardman, S.J.O.,Hoeven, R.,Sakuma, M.,Hay, S.,Leys, D.,Rao, Z.,Zhou, A.,Cheng, Q.,Scrutton, N.S.
Structural basis for enzymatic photocatalysis in chlorophyll biosynthesis.
Nature, 574:722-725, 2019

PubMed Abstract: The enzyme protochlorophyllide oxidoreductase (POR) catalyses a light-dependent step in chlorophyll biosynthesis that is essential to photosynthesis and, ultimately, all life on Earth. POR, which is one of three known light-dependent enzymes, catalyses reduction of the photosensitizer and substrate protochlorophyllide to form the pigment chlorophyllide. Despite its biological importance, the structural basis for POR photocatalysis has remained unknown. Here we report crystal structures of cyanobacterial PORs from Thermosynechococcus elongatus and Synechocystis sp. in their free forms, and in complex with the nicotinamide coenzyme. Our structural models and simulations of the ternary protochlorophyllide-NADPH-POR complex identify multiple interactions in the POR active site that are important for protochlorophyllide binding, photosensitization and photochemical conversion to chlorophyllide. We demonstrate the importance of active-site architecture and protochlorophyllide structure in driving POR photochemistry in experiments using POR variants and protochlorophyllide analogues. These studies reveal how the POR active site facilitates light-driven reduction of protochlorophyllide by localized hydride transfer from NADPH and long-range proton transfer along structurally defined proton-transfer pathways.

PubMed: 31645759
DOI: 10.1038/s41586-019-1685-2

実験手法

X-RAY DIFFRACTION (1.92 Å)