Artificial allosteric control of proteins through mechanical tension

The profound relationship between a proteins conformational change and function is one that lies at the heart of understanding, and possibly controlling biological macromolecules. Most enzymes are regulated through allosteric control, where a molecule is bound to the protein at a site other than its active site, inducing a conformational change in the protein: natures way of chemically switching a macromolecule "on" or "off." There is generally a substantial conformational change in the protein that accompanies the chemical activation of allostery, rendering the protein active to function. It is this conformational change that the protein undergoes which we can induce with externally applied mechanical tension. We exploit this ingenious method of control by chemically attaching a polymer, in this case a 60 base DNA oligomer, to various proteins which behaves as a "molecular spring". The attached DNA oligomer will become drastically rigid upon hybridization of a complementary oligomer - exerting a large enough tension to disrupt the usual function of the protein. Through this research we have developed a protein which has acquired a "switch," allowing us to control the functionality at our discretion. This artificial allosteric technique based on mechanical tension, allows us to study protein dynamics and structure with the ability to modulate the amount of tension applied to the protein. The insertion of this Allosteric Spring Probe is general, it can be applied to virtually any protein, specifically to enzymes which have defined tasks associate with notably conformational changes. This new mechanism which we have developed will lead to new approaches in bioengineering and biophysical studies, and will be the focus of my dissertation.