8KAR

Glutamate dehydrogenase-AKG

8KAR の概要

• エントリーDOI: 10.2210/pdb8kar/pdb
• 分子名称: Glutamate dehydrogenase, 2-OXOGLUTARIC ACID, NICOTINAMIDE-ADENINE-DINUCLEOTIDE, ... (5 entities in total)
• 機能のキーワード: glutamate dehydrogenase, oxidoreductase
• 由来する生物種: Saccharolobus solfataricus
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 139919.87

構造登録者

Sakuraba, H.,Ohshima, T. (登録日: 2023-08-03, 公開日: 2024-08-07, 最終更新日: 2025-08-06)

主引用文献

Okabe, I.,Hirano, M.,Ohmori, T.,Segawa, M.,Yoneda, K.,Ohshima, T.,Sakuraba, H.
Structural insight into the unique substrate specificity of glutamate dehydrogenase from Saccharolobus solfataricus.
Extremophiles, 29:32-32, 2025

PubMed Abstract: The gene (SSO1457) encoding a L-glutamate dehydrogenase (GDH) homolog from the thermoacidophilic archaeon Saccharolobus solfataricus P2 was overexpressed in Escherichia coli. At a substrate concentration of 50 mM, the enzyme (SSO1457) produced exhibited much higher specific activity toward L-norvaline than L-glutamate at temperatures between 55 and 75°C, whereas the enzyme showed higher activity for L-glutamate than L-norvaline at 85°C. The crystal structures of both NAD/2-oxovalerate-bound and NAD/2-oxoglutarate-bound SSO1457 were determined. Comparison of the two structures showed that the positioning of the substrate molecules and the surrounding residues is nearly identical in the two complexes. In the 2-oxoglutarate-bound structure, the C5-carboxylate group of 2-oxoglutarate is hydrogen-bonded with the side chains of Lys72, Arg188, and Ser351, as observed in other GDHs. By contrast, in the 2-oxovalerate-bound structure, the C01, C02, and C03 atoms of 2-oxovalerate are anchored via hydrophobic interactions to the side chains of Met93 and Val348. Site-directed mutagenesis shows that the side chain of Met93 mainly mediates the reactivity of SSO1457 towards L-norvaline and contributes to high specific activities for L-norvaline.

PubMed: 40705132
DOI: 10.1007/s00792-025-01395-1

実験手法

X-RAY DIFFRACTION (1.73 Å)