4Y1P
Crystal structure of 3-isopropylmalate dehydrogenase (Saci_0600) from Sulfolobus acidocaldarius complex with 3-isopropylmalate and Mg2+
Summary for 4Y1P
| Entry DOI | 10.2210/pdb4y1p/pdb |
| Descriptor | 3-isopropylmalate dehydrogenase, MAGNESIUM ION, 3-ISOPROPYLMALIC ACID, ... (5 entities in total) |
| Functional Keywords | beta-decarboxylating dehyrogenase, 3-isopropylmalate dehydrogenase, sulfolobus acidocaldarius, closed form, oxidoreductase |
| Biological source | Sulfolobus acidocaldarius DSM 639 |
| Total number of polymer chains | 2 |
| Total formula weight | 73644.75 |
| Authors | Takahashi, K.,Tomita, T.,Kuzuyama, T.,Nishiyama, M. (deposition date: 2015-02-08, release date: 2016-03-09, Last modification date: 2023-11-08) |
| Primary citation | Takahashi, K.,Nakanishi, F.,Tomita, T.,Akiyama, N.,Lassak, K.,Albers, S.V.,Kuzuyama, T.,Nishiyama, M. Characterization of two beta-decarboxylating dehydrogenases from Sulfolobus acidocaldarius Extremophiles, 20:843-853, 2016 Cited by PubMed Abstract: Sulfolobus acidocaldarius, a hyperthermoacidophilic archaeon, possesses two β-decarboxylating dehydrogenase genes, saci_0600 and saci_2375, in its genome, which suggests that it uses these enzymes for three similar reactions in lysine biosynthesis through 2-aminoadipate, leucine biosynthesis, and the tricarboxylic acid cycle. To elucidate their roles, these two genes were expressed in Escherichia coli in the present study and their gene products were characterized. Saci_0600 recognized 3-isopropylmalate as a substrate, but exhibited slight and no activity for homoisocitrate and isocitrate, respectively. Saci_2375 exhibited distinct and similar activities for isocitrate and homoisocitrate, but no detectable activity for 3-isopropylmalate. These results suggest that Saci_0600 is a 3-isopropylmalate dehydrogenase for leucine biosynthesis and Saci_2375 is a dual function enzyme serving as isocitrate-homoisocitrate dehydrogenase. The crystal structure of Saci_0600 was determined as a closed-form complex that binds 3-isopropylmalate and Mg, thereby revealing the structural basis for the extreme thermostability and novel-type recognition of the 3-isopropyl moiety of the substrate. PubMed: 27590116DOI: 10.1007/s00792-016-0872-4 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.2 Å) |
Structure validation
Download full validation report
