The design, synthesis, and characterization of the first cavitand-based de novo hetero-template-assembled synthetic proteins (Hetero-TASPs)

The design, synthesis, and characterization of novel cavitand-based hetero-TASPs, TASPs having different peptide sequences within one bundle, are described. Three families of hetero-TASPs were designed: the LG3/LG2 family (different linker lengths), LG3/AG3 family ( altering helix hydrophobicity), and the LG3/LG2C family (anti-parallel caviteins). These first generation hetero-TASPs were found to be alpha-helical, stable towards guanidine hydrochloride, and monomeric in solution. The LG3/LG2 caviteins exhibited primarily native-like properties. The remaining hetero-TASP families were found to exhibit less dispersion and broader signals in the amide regions of their H-1 NMR spectra than their respective reference caviteins. The success in the design of the LG3/ LG2 hetero-TASPs suggests that subsequent hetero-TASPs may have potential to manifest superior native-like structure compared with homo-TASPs, and refinement of the linker and peptide sequences may accomplish this goal.