Structures of Helical β-Tapes and Twisted Ribbons:  The Role of Side-Chain Interactions on Twist and Bend Behavior

Fishwick, Colin W. G.; Beevers, Andrew J.; Carrick, Lisa M.; Whitehouse, Conor; Aggeli, and Amalia; Boden, N.

doi:10.1021/nl034095p

Cited by 137 publications

(124 citation statements)

References 18 publications

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“…During the self-assembly process an attractive force (hydrogen bonds and hydrophobic interactions) most likely opposes electrostatic repulsion to define the final structures of peptide self-assembly (11,26). This may explain the coexistence of flat ribbons and helical fibrils: The flattening seen in ribbons is compensated by the energy gained from the stacking of strands, which correlates well with the observation that flat ribbons need to exceed a certain height to transform into twisted fibrils (44). Mutations of individual side chains likely shift this balance and destabilize the tubes sufficiently relative to the twisted ribbons to lead to their complete elimination.…”

Section: Discussionsupporting

confidence: 59%

See 1 more Smart Citation

Coexistence of ribbon and helical fibrils originating from hIAPP _20–29 revealed by quantitative nanomechanical atomic force microscopy

Zhang

Andreasen

Nielsen

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

107

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Uncontrolled misfolding of proteins leading to the formation of amyloid deposits is associated with more than 40 types of diseases, such as neurodegenerative diseases and type-2 diabetes. These irreversible amyloid fibrils typically assemble in distinct stages. Transitions among the various intermediate stages are the subject of many studies but are not yet fully elucidated. Here, we combine high-resolution atomic force microscopy and quantitative nanomechanical mapping to determine the self-assembled structures of the decapeptide hIAPP [20][21][22][23][24][25][26][27][28][29] , which is considered to be the fibrillating core fragment of the human islet amyloid polypeptide (hIAPP) involved in type-2 diabetes. We successfully follow the evolution of hIAPP 20-29 nanostructures over time, calculate the average thickening speed of small ribbon-like structures, and provide evidence of the coexistence of ribbon and helical fibrils, highlighting a key step within the self-assembly model. In addition, the mutations of individual side chains of wide-type hIAPP 20-29 shift this balance and destabilize the helical fibrils sufficiently relative to the twisted ribbons to lead to their complete elimination. We combine atomic force microscopy structures, mechanical properties, and solid-state NMR structural information to build a molecular model containing β sheets in cross-β motifs as the basis of selfassembled amyloids.μFS | mutants | nanomechanical map | self-assembly nanostructure P rotein aggregation and amyloid deposits (1, 2) are associated with more than 40 different diseases (3) ranging from neurodegenerative diseases such as Alzheimer's disease (4) and Parkinson disease (5) to systemic amyloidosis, such as type-2 diabetes mellitus (T2D) (6). Over the last few decades, amyloid structures and amyloid assembly have been extensively studied using a variety of diffraction techniques such as X-ray scattering and electron diffraction. However, these methods only provide average structures (7). Many structures have also been resolved in great detail by solid-state NMR spectroscopy (8, 9), which mainly represents end-point structures and, unless specifically trapping intermediates, typically does not provide a clear picture of the transient structures formed during the fibrillation process. However, it is very important to resolve the dynamics of the nanostructures of amyloids at various steps during self-assembly to understand the mechanics behind amyloid initialization, formation, growth, and maturation as well as for the design of potential drugs. Atomic force microscopy (AFM) is capable of obtaining nanoscale resolution of individual molecules or supermolecular structures. This method also allows for the analysis of the selfassembly mechanism and the driving force of aggregation (10-14). Importantly, AFM, furthermore, provides the possibility to follow the dynamics to obtain a detailed picture of the amyloid assembly process (15).In the case of T2D, amyloid deposits, composed mainly of human islet amyloid polypeptide (hIA...

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Section: Discussionsupporting

confidence: 59%

“…Hence, we propose that when the thickness of the ribbon exceeds a certain threshold (Fig. S7) the ribbon may be energetically stable, and survive (44). Conversely, thinner ribbons have two possible configurations: They can either change to fibrils (Fig.…”

Section: Discussionmentioning

confidence: 99%

Coexistence of ribbon and helical fibrils originating from hIAPP _20–29 revealed by quantitative nanomechanical atomic force microscopy

Zhang

Andreasen

Nielsen

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

107

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“…Note that helical nanoribbons provide a fertile ground for such effects. Both the helicoid (a minimal surface) and helical nanoribbons are ubiquitous in nature; biomolecules in particular [1][2][3][4] . A helicoid has two chiralities ( Fig.…”

Section: Avadh Saxenamentioning

confidence: 99%

Helicoidal graphene nanoribbons: Chiraltronics

Atanasov

Saxena

2015

Phys. Rev. B

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We present a calculation of the effective geometry-induced quantum potential for the carriers in graphene shaped as a helicoidal nanoribbon. In this geometry the twist of the nanoribbon plays the role of an effective transverse electric field in graphene and this is reminiscent of the Hall effect. However, this effective electric field has a different sign for the two iso-spin states and translates into a mechanism to separate the two chiral species on the opposing rims of the nanoribbon. Iso-spin transitions are expected with the emission or absorption of microwave radiation which could be adjusted to be in the THz region.

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“…Tremendous peptides have been studied for self-assembling -sheet secondary structures. The -sheet consists of alternating hydrophilic and hydrophobic amino acids in the peptide sequence, which can provide amphiphilic property to the peptide that drives the self-assembly ofsheets [96]. The -sheet peptides also could be utilized to form many different nanostructures including nanotubes, monolayers in nanoscale order, and nanoribbons [97][98][99][100][101].…”

Section: -Sheet Peptidementioning

confidence: 99%

Peptide Self-Assembled Nanostructures for Drug Delivery Applications

Fan

Shen

et al. 2017

Journal of Nanomaterials

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Peptide self-assembled nanostructures are very popular in many biomedical applications. Drug delivery is one of the most promising applications among them. The tremendous advantages for peptide self-assembled nanostructures include good biocompatibility, low cost, tunable bioactivity, high drug loading capacities, chemical diversity, specific targeting, and stimuli responsive drug delivery at disease sites. Peptide self-assembled nanostructures such as nanoparticles, nanotubes, nanofibers, and hydrogels have been investigated by many researchers for drug delivery applications. In this review, the underlying mechanisms for the self-assembled nanostructures based on peptides with different types and structures are introduced and discussed. Peptide self-assembled nanostructures associated promising drug delivery applications such as anticancer drug and gene drug delivery are highlighted. Furthermore, peptide self-assembled nanostructures for targeted and stimuli responsive drug delivery applications are also reviewed and discussed.

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Structures of Helical β-Tapes and Twisted Ribbons: The Role of Side-Chain Interactions on Twist and Bend Behavior

Cited by 137 publications

References 18 publications

Coexistence of ribbon and helical fibrils originating from hIAPP _20–29 revealed by quantitative nanomechanical atomic force microscopy

Coexistence of ribbon and helical fibrils originating from hIAPP _20–29 revealed by quantitative nanomechanical atomic force microscopy

Helicoidal graphene nanoribbons: Chiraltronics

Peptide Self-Assembled Nanostructures for Drug Delivery Applications

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Structures of Helical β-Tapes and Twisted Ribbons: The Role of Side-Chain Interactions on Twist and Bend Behavior

Cited by 137 publications

References 18 publications

Coexistence of ribbon and helical fibrils originating from hIAPP 20–29 revealed by quantitative nanomechanical atomic force microscopy

Coexistence of ribbon and helical fibrils originating from hIAPP 20–29 revealed by quantitative nanomechanical atomic force microscopy

Helicoidal graphene nanoribbons: Chiraltronics

Peptide Self-Assembled Nanostructures for Drug Delivery Applications

Contact Info

Product

Resources

About

Coexistence of ribbon and helical fibrils originating from hIAPP _20–29 revealed by quantitative nanomechanical atomic force microscopy

Coexistence of ribbon and helical fibrils originating from hIAPP _20–29 revealed by quantitative nanomechanical atomic force microscopy