4AEC

Crystal Structure of the Arabidopsis thaliana O-Acetyl-Serine-(Thiol)- Lyase C

4AEC の概要

• エントリーDOI: 10.2210/pdb4aec/pdb
• 分子名称: CYSTEINE SYNTHASE, MITOCHONDRIAL, PYRIDOXAL-5'-PHOSPHATE, ACETATE ION, ... (5 entities in total)
• 機能のキーワード: lyase, cysteine synthesis, assimilatory sulfate reduction, sulfide, plant inorganic sulfur uptake
• 由来する生物種: ARABIDOPSIS THALIANA
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 92433.79

構造登録者

Feldman-Salit, A.,Wirtz, M.,Lenherr, E.D.,Throm, C.,Hothorn, M.,Scheffzek, K.,Hell, R.,Wade, R.C. (登録日: 2012-01-09, 公開日: 2012-02-22, 最終更新日: 2023-12-20)

主引用文献

Feldman-Salit, A.,Wirtz, M.,Lenherr, E.D.,Throm, C.,Hothorn, M.,Scheffzek, K.,Hell, R.,Wade, R.C.
Allosterically Gated Enzyme Dynamics in the Cysteine Synthase Complex Regulate Cysteine Biosynthesis in Arabidopsis Thaliana.
Structure, 20:292-, 2012

PubMed Abstract: Plants and bacteria assimilate sulfur into cysteine. Cysteine biosynthesis involves a bienzyme complex, the cysteine synthase complex (CSC), which consists of serine-acetyl-transferase (SAT) and O-acetyl-serine-(thiol)-lyase (OAS-TL) enzymes. The activity of OAS-TL is reduced by formation of the CSC. Although this reduction is an inherent part of the self-regulation cycle of cysteine biosynthesis, there has until now been no explanation as to how OAS-TL loses activity in plants. Complexation of SAT and OAS-TL involves binding of the C-terminal tail of SAT in one of the active sites of the homodimeric OAS-TL. We here explore the flexibility of the unoccupied active site in Arabidopsis thaliana cytosolic and mitochondrial OAS-TLs. Our results reveal two gates in the OAS-TL active site that define its accessibility. The observed dynamics of the gates show allosteric closure of the unoccupied active site of OAS-TL in the CSC, which can hinder substrate binding, abolishing its turnover to cysteine.

PubMed: 22325778
DOI: 10.1016/J.STR.2011.11.019

実験手法

X-RAY DIFFRACTION (2.4 Å)