mz7b00324_si_001.pdf (9.51 MB)
Folding Cooperativity of Synthetic Polypeptides with or without “Tertiary” Interactions
journal contribution
posted on 2017-06-23, 18:48 authored by Yuan Ren, Hailin Fu, Ryan Baumgartner, Yanfeng Zhang, Jianjun Cheng, Yao LinModel-based studies
on helix–coil transition and folding
cooperativity of synthetic polypeptides have contributed to the understanding
of protein folding and stability and to the development of polypeptide-based
functional materials. Polypeptide-containing macromolecules with complex
architectures, however, remain a challenge in the model-based analysis.
Herein, a modified Schellman–Zimm–Bragg model has been
utilized to quantitatively analyze the folding cooperativity of polypeptide-containing
macromolecules. While the helix–coil transition of homopolypeptides
(e.g., poly(ε-benzyloxycarbonyl-l-lysine) (PZLL)) can
be described by the classic model, the folding of grafted polypeptide
chains in the comb macromolecules (e.g., polynorbornene-g-poly(ε-benzyloxycarbonyl-l-lysine) (PN-g-PZLL)) cannot be accurately predicted by the existing theories,
due to the side-chain interactions between grafted polypeptides in
the comb macromolecules. Incorporating nonlocal interaction explicability
into the statistical mechanics treatment is found to be instructive
to account for the possible “tertiary” interactions
of polypeptides in the macromolecules with complex architectures.