4IX3

Crystal structure of a Stt7 homolog from Micromonas algae

4IX3 の概要

• エントリーDOI: 10.2210/pdb4ix3/pdb
• 関連するPDBエントリー: 4IX4 4IX5 4IX6
• 分子名称: MsStt7d protein, MAGNESIUM ION (3 entities in total)
• 機能のキーワード: protein kinase, canonical protein kinase fold, atp binding, transferase
• 由来する生物種: Micromonas (green algae)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 75563.03

構造登録者

Guo, J.,Wei, X.,Li, M.,Pan, X.,Chang, W.,Liu, Z. (登録日: 2013-01-24, 公開日: 2013-10-02, 最終更新日: 2024-03-20)

主引用文献

Guo, J.,Wei, X.,Li, M.,Pan, X.,Chang, W.,Liu, Z.
Structure of the catalytic domain of a state transition kinase homolog from Micromonas algae
Protein Cell, 4:607-619, 2013

PubMed Abstract: Under natural environments, plants and algae have evolved various photosynthetic acclimation mechanisms in response to the constantly changing light conditions. The state transition and long-term response processes in photosynthetic acclimation involve remodeling and composition alteration of thylakoid membrane. A chloroplast protein kinase named Stt7/STN7 has been found to have pivotal roles in both state transition and long-term response. Here we report the crystal structures of the kinase domain of a putative Stt7/STN7 homolog from Micromonas sp. RCC299 (MsStt7d) in the apo form and in complex with various nucleotide substrates. MsStt7d adopts a canonical protein kinase fold and contains all the essential residues at the active site. A novel hairpin motif, found to be a conserved feature of the Stt7/STN7 family and indispensable for the kinase stability, interacts with the activation loop and fixes it in an active conformation. We have also demonstrated that MsStt7d is a dualspecifi city kinase that phosphorylates both Thr and Tyr residues. Moreover, preliminary in vitro data suggest that it might be capable of phosphorylating a consensus N-terminal pentapeptide of light-harvesting proteins Micromonas Lhcp4 and Arabidopsis Lhcb1 directly. The potential peptide/protein substrate binding site is predicted based on the location of a pseudo-substrate contributed by the adjacent molecule within the crystallographic dimer. The structural and biochemical data presented here provide a framework for an improved understanding on the role of Stt7/STN7 in photosynthetic acclimation.

PubMed: 23794031
DOI: 10.1007/s13238-013-3034-9

実験手法

X-RAY DIFFRACTION (1.35 Å)