After a biochemist like Blanke determines that a particular protein triggers a bacteria to spread uncontrollably, he or she might call in a crystallographer like Krause to analyze the protein. Krause uses a technique that dates from the beginning of modern physics. He blasts x-rays through molecules arranged in a crystal and examines the deflection pattern to determine where the atoms that make up the molecule are positioned. These details are far too small to see even with a microscope. In biological systems, proteins and enzymes react with each other on the basis of their shapes.
Proteins are the cogs and gears of bacteria.
Thus, a protein might be responsible for grabbing another square-shaped protein and passing it to a third protein. While this may seem abstract, Krause can attest to the early impact that crystallography has on patients. Every Monday you'll find him working at a Harris County HIV clinic. It's a challenge to make time for the clinic with the other demands on a professor's time, but Krause is committed to it. In fact, the new protease inhibitors that are dramatically extending the lives of HIV patients were designed in part through the teamwork of crystallographers and computational chemists.