Locate within the Protein Data Bank the 3-dimensional structure of an oxidoreductase enzyme without a bound ligand. Download the coordinates for the structure and use Rasmol to investigate the structure.

Using Rasmol produce an image of the oxidoreductase structure that you have downloaded that clearly illustrates the catalytic site of the enzyme. State and show in your image the active site residues. 

Making reference to the PDB reference code of your protein detail those commands you used in Rasmol to produce your image.