8KAO
Glutamate dehydrogenase-69O
Summary for 8KAO
| Entry DOI | 10.2210/pdb8kao/pdb |
| Descriptor | Glutamate dehydrogenase, NICOTINAMIDE-ADENINE-DINUCLEOTIDE, 2-oxopentanoic acid, ... (4 entities in total) |
| Functional Keywords | glutamate dehydrogenase, oxidoreductase |
| Biological source | Saccharolobus solfataricus |
| Total number of polymer chains | 3 |
| Total formula weight | 137463.96 |
| Authors | Sakuraba, H.,Ohshima, T. (deposition date: 2023-08-03, release date: 2024-08-07, Last modification date: 2025-08-06) |
| Primary citation | 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 Cited by 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: 40705132DOI: 10.1007/s00792-025-01395-1 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.55 Å) |
Structure validation
Download full validation report
