The discovery and application of new types of helical peptidic foldamers have been an attractive endeavor to enable the development of new materials, catalysts and biological molecules. To maximize their application potential through structure-based design, it is imperative to control their helical handedness based on their molecular scaffold. Herein we first demonstrate the generalizability of the solid-state right-handed helical propensity of the 413-helix of L-α/L-sulfono-γ-AA peptides that as short as 11-mer, using the high-resolution X-ray single crystallography. The atomic level folding conformation of the foldamers was also elucidated by 2D NMR and circular dichroism under various conditions. Subsequently, we show that the helical handedness of this class of foldamer is controlled by the chirality of their chiral side chains, as demonstrated by the left-handed 413-helix comprising 1:1 D-α/D-sulfono-γ-AA peptide. In addition, a heterochiral coiled-coil-like structure was also revealed for the first time, unambiguously supporting the impact of chirality on their helical handedness. Our findings enable the structure-based design of unique folding biopolymers and materials with the exclusive handedness or the racemic form of the foldamers in the future.
Monodisperse, sequence‐specific oligomers that adopt regular three‐dimensional structures, termed foldamers, have found widespread use as biomimetics, sensors, and novel materials. This review highlights recent examples in which steady state and time‐resolved fluorescence techniques have clarified foldamer structure or enabled the development of foldamers with exciting and sophisticated functions. Applications of foldamers include their development into bioactive compounds, supramolecular hosts or sensors, and materials with useful optical properties. Examples that illustrate the use of natively fluorescent and fluorophore‐modified foldamers are discussed along with studies of fluorophore interactions with varied dyes.
more » « less- Award ID(s):
- 1904991
- NSF-PAR ID:
- 10257936
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Israel Journal of Chemistry
- Volume:
- 61
- Issue:
- 3-4
- ISSN:
- 0021-2148
- Page Range / eLocation ID:
- p. 185-198
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Most constructionist efforts have focused on supporting learners with tools for designing with digital and/or physical media. Recent developments in life sciences now allow K‐12 learners to design with living materials, or to biodesign. In this paper, we report on the development of a biodesign studio activity called biocakes wherein teams of high school youth genetically modified a yeast strain to bake a nutrient fortified food product. Using a qualitative deductive analysis of classroom observations, interviews and projects, we examined high school youth experiences and reflections of these activities to answer three research questions: (1) What kind of artefacts did youth make with living media? (2) How did youth engage in biodesign? and (3) What did youth have to say about their biodesign experiences? We discuss how our analyses of biodesign applications highlight the importance of assembly practices, social engagement and imaginative design for constructionist learning. These insights provide compelling examples for designing with living media in K‐12 education.
Practitioner notes What is already known about this topic?
Constructionist perspectives shape important ideas about what we know about science learning, and notably in computer science fields.
One widely taken up example includes making, where learners use crafts to make interactive computational objects.
In life science, constructionism also provides insights about learning using digital media to model biological systems or interact with living materials.
What this paper adds?
This paper extends these perspectives by examining production and engagement when learners construct
with living materials—an approach that has only recently been possible with the development of accessible wet lab tools.We frame learning activities as a studio model—that emphasised application design, iteration and critique—to better assess the roles assembly, construction and speculative design play in production that uses living materials.
Our findings suggest that assembly is important for creating accessible points of entry to complex biological fabrication processes.
We also find that speculative design provides an opportunity for learners to extend their existing abilities beyond what is otherwise available given their expertise or access to resources, and thus expansively explore related ideas.
Implications for practice and/or policy
Assembly and speculative design have important places in constructionist‐driven production with living materials and could, therefore, be leveraged in practice.
