Download or read book Development of a Quantum Mechanical Computational Model for the Catalytic Active Site of Sulfite Oxidase written by Lindsay S. Farr and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The molybdenum-containing sulfite oxidase enzyme is a mitochondrial protein that catalyzes the terminal step in sulfur containing amino acid degradation. It is a highly conserved enzyme across all eukaryotic organisms, excluding yeasts. In humans, the oxidation reaction catalyzed by sulfite oxidase is essential for infant development, and a rare genetic disease occurs in the absence of a functional sulfite oxidase. The structural and mechanistic details of this enzyme are currently ambiguous. Previous computational approaches have failed to provide details of the mechanism or establish the validity of their computational model. Here, we investigate the complex active site environment of the enzyme using computational tools and report a realistic in silico model. In agreement with previous model developments for molybdenum containing enzymes by the Biswas Research Lab, we have emphasized the importance of secondary and third sphere residues on the geometric structures of the active site. We investigated three distinct models and propose that our model 3 (~248 atoms) is a realistic computational model for SO. These models are developed using a systematic approach of model growth to include all necessary second and third sphere residues. We also investigate the proton network of the active site by allowing different protonation states of certain residues within the proximity of the site of reaction. We are in the process of validating this model using experimental data (such as redox potential). The catalytic mechanism of SO may be more reliably investigated with our proposed quantum mechanical model once the model is validated using experimental data.