1KH3

Crystal Structure of Thermus thermophilus HB8 Argininosuccinate Synthetase in complex with inhibitor

1KH3 の概要

• エントリーDOI: 10.2210/pdb1kh3/pdb
• 関連するPDBエントリー: 1KH1 1KH2
• 分子名称: Argininosuccinate Synthetase, SULFATE ION, MAGNESIUM ION, ... (7 entities in total)
• 機能のキーワード: ligase, riken structural genomics/proteomics initiative, rsgi, structural genomics
• 由来する生物種: Thermus thermophilus
• 細胞内の位置: Cytoplasm (Probable): P59846
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 183243.47

構造登録者

goto, m.,Hirotsu, k.,miyahara, i.,RIKEN Structural Genomics/Proteomics Initiative (RSGI) (登録日: 2001-11-29, 公開日: 2003-04-22, 最終更新日: 2024-03-13)

主引用文献

Goto, M.,Omi, R.,Miyahara, I.,Sugahara, M.,Hirotsu, k.
Structures of Argininosuccinate Synthetase in Enzyme-ATP Substrates and Enzyme-AMP Product Forms: STEREOCHEMISTRY OF THE CATALYTIC REACTION
J.Biol.Chem., 278:22964-22971, 2003

PubMed Abstract: Argininosuccinate synthetase reversibly catalyzes the ATP-dependent condensation of a citrulline with an aspartate to give argininosuccinate. The structures of the enzyme from Thermus thermophilus HB8 complexed with intact ATP and substrates (citrulline and aspartate) and with AMP and product (argininosuccinate) have been determined at 2.1- and 2.0-A resolution, respectively. The enzyme does not show the ATP-induced domain rotation observed in the enzyme from Escherichia coli. In the enzyme-substrate complex, the reaction sites of ATP and the bound substrates are adjacent and are sufficiently close for the reaction to proceed without the large conformational change at the domain level. The mobility of the triphosphate group in ATP and the side chain of citrulline play an important role in the catalytic action. The protonated amino group of the bound aspartate interacts with the alpha-phosphate of ATP and the ureido group of citrulline, thus stimulating the adenylation of citrulline. The enzyme-product complex explains how the citrullyl-AMP intermediate is bound to the active site. The stereochemistry of the catalysis of the enzyme is clarified on the basis of the structures of tAsS (argininosuccinate synthetase from T. thermophilus HB8) complexes.

PubMed: 12684518
DOI: 10.1074/jbc.M213198200

実験手法

X-RAY DIFFRACTION (2.15 Å)