Related Experiment Video
Updated: Jun 16, 2026

Anaerobic Protein Purification and Kinetic Analysis via Oxygen Electrode for Studying DesB Dioxygenase Activity and Inhibition
Published on: October 3, 2018
Molecular basis of sulfite oxidase deficiency from the structure of sulfite oxidase
C Kisker1, H Schindelin, A Pacheco
1Howard Hughes Medical Institute and Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena 91125, USA. kisker@citray.caltech.edu
Abstract:
The molybdenum-containing enzyme sulfite oxidase catalyzes the conversion of sulfite to sulfate, the terminal step in the oxidative degradation of cysteine and methionine. Deficiency of this enzyme in humans usually leads to major neurological abnormalities and early death. The crystal structure of chicken liver sulfite oxidase at 1.9 A resolution reveals that each monomer of the dimeric enzyme consists of three domains. At the active site, the Mo is penta-coordinated by three sulfur ligands, one oxo group, and one water/hydroxo. A sulfate molecule adjacent to the Mo identifies the substrate binding pocket. Four variants associated with sulfite oxidase deficiency have been identified: two mutations are near the sulfate binding site, while the other mutations occur within the domain mediating dimerization.
More Related Videos
08:57Simultaneous Measurement of Superoxide/Hydrogen Peroxide and NADH Production by Flavin-containing Mitochondrial Dehydrogenases
Published on: February 24, 2018
12:08Monitoring the Reductive and Oxidative Half-Reactions of a Flavin-Dependent Monooxygenase using Stopped-Flow Spectrophotometry
Published on: March 18, 2012
Related Concept Videos
Sulfur Assimilation
Structure and Nomenclature of Thiols and Sulfides
Gene Families
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
Electron Transport Chain: Complex I and II
ROS generation is regulated and maintained at moderate levels necessary...
Preparation and Reactions of Sulfides
Electron Transport Chain: Complex III and IV