8S5S
Crystal structure of a Sulfite dehydrogenase from Thermus thermophilus
Summary for 8S5S
Entry DOI | 10.2210/pdb8s5s/pdb |
Descriptor | Putaitve sulfite oxidase, (MOLYBDOPTERIN-S,S)-OXO-MOLYBDENUM, CHLORIDE ION, ... (4 entities in total) |
Functional Keywords | electron transfer, sor, molybdopterine, oxidoreductase |
Biological source | Thermus thermophilus HB8 |
Total number of polymer chains | 1 |
Total formula weight | 43696.76 |
Authors | Djeghader, A.,Soulimane, T. (deposition date: 2024-02-25, release date: 2024-11-27, Last modification date: 2024-12-11) |
Primary citation | Djeghader, A.,Rendon, J.,Biaso, F.,Gerbaud, G.,Nitschke, W.,Schoepp-Cothenet, B.,Soulimane, T.,Grimaldi, S. Structural and Spectroscopic Investigations of pH-Dependent Mo(V) Species in a Bacterial Sulfite-Oxidizing Enzyme. Inorg.Chem., 63:22699-22711, 2024 Cited by PubMed Abstract: Mono-pyranopterin-containing sulfite-oxidizing enzymes (SOEs), including eukaryotic sulfite oxidases and homologous prokaryotic sulfite dehydrogenases (SDHs), are molybdenum enzymes that exist in almost all forms of life, where they catalyze the direct oxidation of sulfite into sulfate, playing a key role in protecting cells and organisms against sulfite-induced damage. To decipher their catalytic mechanism, we have previously provided structural and spectroscopic evidence for direct coordination of HPO to the Mo atom at the active site of the SDH from the hyperthermophilic bacterium (SDH), mimicking the proposed sulfate-bound intermediate proposed to be formed during catalysis. In this work, by solving the X-ray crystallographic structure of the unbound enzyme, we resolve the changes in the hydrogen bonding network in the molybdenum environment that enable the stabilization of the previously characterized phosphate adduct. In addition, electron paramagnetic resonance spectroscopic study of the enzyme over a wide pH range reveals the formation of pH-dependent Mo(V) species, a characteristic feature of eukaryotic SOEs. The combined use of HYSCORE, HO/DO exchange, and density functional theory calculations allows the detailed characterization of a typical low pH Mo(V) species previously unreported in bacterial SOEs, underlining the conservation of the active site properties of SOEs irrespective of their source organism. PubMed: 39561325DOI: 10.1021/acs.inorgchem.4c02584 PDB entries with the same primary citation |
Experimental method | X-RAY DIFFRACTION (1.85 Å) |
Structure validation
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