Tuning stoichiometry and physical interactions of peptide rigid rods through ‘click’ chemistry of computationally designed coiled coil

With computational design, peptide sequences can be customized to form specific solution self-assembly structures and to promote interactions that favor formation of unique structures such as nanotubes, needles, 2D plates. A recent publication of our collaborative group has shown that peptide rigid rods of various lengths can be formed from conjugation of N-terminal modified, anti-parallel, tetrameric coiled coil bundles by thiol-Michael reaction. Lyotropic liquid crystal behavior was observed and strong mechanical properties were expected from these peptide rods. In this work, further investigation into fine-tuning liquid crystal behavior of peptide rods and improving ‘click’ chemistry stoichiometry were carried out with computationally designed sequences. Highly charged coiled coil sequences were designed to showcase a tunable liquid crystal behavior through changing solution conditions and parallel coiled coil were designed to have inherent 1:1 stoichiometry at each end of bundle for long rods formation. Coiled coil design and preliminary results will be discussed.