Designing the Binding Surface of Proteins to Construct Nano-fibers

Abstract

In the field of nanotechnology, a variety of applications have been anticipated. We have been trying to design nano-fibers using proteins while maintaining their native structures. We try to use Lac repressor two-helix protein (LARFH), sulerythrin, and 3-isopropylmalate dehydrogenase (IPMDH) as adaptors for constructing nano-fibers. By making use of the α-helices outside of respective proteins, we are trying to form binding site between proteins: two α-helices of one protein are designed to form four-helix bundle with two α-helices of another protein. In addition, by introducing mutations in amino acids at the binding sites, hydrophobic and electrostatic interactions can be modified. The fiber may be produced upon mixing the two kinds of proteins. By umbrella sampling simulation, we have found that in the combination of LARFH-/-LARFH, hydrophobic interaction is enhanced in wild type, and electrostatic interaction is enhanced in variant. We also found high stability of IPMDH-/-IPMDH.