3THG

Crystal structure of the creosote Rubisco activase C-domain

3THG の概要

• エントリーDOI: 10.2210/pdb3thg/pdb
• 分子名称: Ribulose bisphosphate carboxylase/oxygenase activase 1, chloroplastic, GLYCEROL (3 entities in total)
• 機能のキーワード: four-helix bundle, rubisco reactivation, chloroplast stroma, aaa+, atpase, protein binding
• 由来する生物種: Larrea tridentata (Creosote bush)
• 細胞内の位置: Plastid, chloroplast stroma (By similarity): Q7X9A0
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 12114.72

構造登録者

Henderson, J.N.,Kuriata, A.M.,Fromme, R.,Salvucci, M.E.,Wachter, R.M. (登録日: 2011-08-18, 公開日: 2011-08-31, 最終更新日: 2024-02-28)

主引用文献

Henderson, J.N.,Kuriata, A.M.,Fromme, R.,Salvucci, M.E.,Wachter, R.M.
Atomic resolution x-ray structure of the substrate recognition domain of higher plant ribulose-bisphosphate carboxylase/oxygenase (Rubisco) activase.
J.Biol.Chem., 286:35683-35688, 2011

PubMed Abstract: The rapid release of tight-binding inhibitors from dead-end ribulose-bisphosphate carboxylase/oxygenase (Rubisco) complexes requires the activity of Rubisco activase, an AAA+ ATPase that utilizes chemo-mechanical energy to catalyze the reactivation of Rubisco. Activase is thought to play a central role in coordinating the rate of CO(2) fixation with the light reactions of photosynthesis. Here, we present a 1.9 Å crystal structure of the C-domain core of creosote activase. The fold consists of a canonical four-helix bundle, from which a paddle-like extension protrudes that entails a nine-turn helix lined by an irregularly structured peptide strand. The residues Lys-313 and Val-316 involved in the species-specific recognition of Rubisco are located near the tip of the paddle. An ionic bond between Lys-313 and Glu-309 appears to stabilize the glycine-rich end of the helix. Structural superpositions onto the distant homolog FtsH imply that the paddles extend away from the hexameric toroid in a fan-like fashion, such that the hydrophobic sides of each blade bearing Trp-302 are facing inward and the polar sides bearing Lys-313 and Val-316 are facing outward. Therefore, we speculate that upon binding, the activase paddles embrace the Rubisco cylinder by placing their hydrophobic patches near the partner protein. This model suggests that conformational adjustments at the remote end of the paddle may relate to selectivity in recognition, rather than specific ionic contacts involving Lys-313. Additionally, the superpositions predict that the catalytically critical Arg-293 does not interact with the bound nucleotide. Hypothetical ring-ring stacking and peptide threading models for Rubisco reactivation are briefly discussed.

PubMed: 21880724
DOI: 10.1074/jbc.C111.289595

実験手法

X-RAY DIFFRACTION (1.88 Å)