Movie shows the active site of sulfite oxidase, an enzyme essential for normal neurological development in children. Movie shows the active site of sulfite oxidase, an enzyme essential for normal neurological development in children.

It may look like a gyrating, Skittle-eating cloud, but it actually represents the active site of sulfite oxidase, an enzyme essential for normal neurological development in children. Look deep inside the channel opening to see a ball-and-stick model of a complex containing the element molybdenum (light blue ball) that helps pass an oxygen atom (red ball at far end of channel) to trigger a catalytic reaction. The channel itself is lined with a chloride ion (green) and water molecules (red). Knowing more about the enzyme's active site will help scientists better understand sulfite oxidase deficiency, a fatal neurological disease. Courtesy of bioinorganic chemist John H. Enemark at the University of Arizona.

Featured in the July 21, 2010, issue of Biomedical Beat.