Intrinsically disordered proteins (IDPs) are a class of proteins that lack stable three-dimensional structures. Despite their natural tendency to be disordered, precise modulations of molecular parameters (e.g., sequence, length) through biomolecular engineering tools and control of environmental conditions tailor the formation of dynamic self-assembled structures. In addition to designing structures that respond to external stimuli for specific biotechnological applications (e.g., biosensors), other applications require stable structures (e.g., engineered tissues, drug delivery vehicles) that resist unintended changes and disassembly across various environmental conditions, such as different concentrations and temperatures. This review provides a comprehensive understanding of the design and engineering principles that govern the self-assembly of biosynthetic IDPs and their stability. Specifically, elastin-like polypeptides (ELPs) are highlighted as a prominent example of biosynthetically designed, thermoresponsive IDPs. Examples include ELPs that form various self-assembled structures by themselves as ELP homopolymers or diblock copolymers, ELPs combined with other IDPs in diblock copolymers, and ELP-based polymer hybrids containing functional (bio)molecules. It is anticipated that the efforts to enhance the stability of self-assembled structures through the precise engineering of IDP-based polymers have expanded the potential for diverse biotechnological applications in tissue engineering, drug delivery, diagnostic assays, and biomedicine.
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Secondary structures in synthetic polypeptides from N -carboxyanhydrides: design, modulation, association, and material applications
Synthetic polypeptides derived from the ring-opening polymerization of N -carboxyanhydrides can spontaneously fold into stable secondary structures under specific environmental conditions. These secondary structures and their dynamic transitions play an important role in regulating the properties of polypeptides in self-assembly, catalysis, polymerization, and biomedical applications. Here, we review the current strategies to modulate the secondary structures, and highlight the conformation-specific dynamic properties of synthetic polypeptides and the corresponding materials. A number of mechanistic studies elucidating the role of secondary structures are discussed, aiming to provide insights into the new designs and applications of synthetic polypeptides. We aim for this article to bring to people's attention synthetic polymers with ordered conformations, which may exhibit association behaviors and material properties that are otherwise not found in polymers without stable secondary structures.
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- NSF-PAR ID:
- 10093255
- Date Published:
- Journal Name:
- Chemical Society Reviews
- Volume:
- 47
- Issue:
- 19
- ISSN:
- 0306-0012
- Page Range / eLocation ID:
- 7401 to 7425
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c8cs00095f
