Using x-ray crystallography to solve protein structure is the focus in our lab. The dance interprets the difficult and time consuming process of obtaining a 3-dimensional protein structure, which is crucial for not just understanding the cellular function but also provides a fundamental step to drug design.
As a structural biologist, I hope to take the viewers on a journey into the world of x-ray crystallography through several key stages. Different outfits and music divide each stage. Rather than employing multiple dancers, I intentionally limited the performance down to one actor to show more clearly the continuity from one stage to the next.
1. Production of protein: the most common method to produce large quantities of protein is through the use of a bacterium called Escherichia coli (me). This bacterium is equipped with several flagella (my arms and legs), enabling it to be an excellent swimmer. The flapping movement and ripple effects propel the bacterium towards a chemical. Once the bacterium consumes it, production of proteins begins!
2. Affinity purification: the bacterium is killed via sonication indicated by the trembling movement of gradual collapse, and proteins are released as indicated by the variety of color balls. Next stage is an intimate process, much like a relationship between the child and mother. Only “blue” proteins (child) show affection to the affinity beads (mother, me).
3. Crystallization setup: the scientist (me) takes “blue” protein and tries to find the best crystallization condition. Only certain spatial protein rearrangements and packing result in a small box resembling “unit cell”, which is the basic unit of a crystal.
4. X-ray diffraction: high-energy x-ray beam is shot through the unit cell to produce a diffraction pattern on a screen (me)!
5. Building a 3-dimensional protein structure: the diffraction pattern contains all the information about the protein structure, but requires a combination of mathematical algorithms and computer software to solve it. A final model contains 4 helical structures (my arms and legs). As reflected in the locking/robotic dance steps, the helical structures are rigid but can be rearranged spatially to form a 3-dimensional structure.