ROBUSTNESS-STRENGTH PERFORMANCE OF HIERARCHICAL ALPHA-HELICAL PROTEIN FILAMENTS

An abundant trait of biological protein materials are hierarchical nanostructures, ranging through atomistic, molecular to macroscopic scales. By utilizing the recently developed Hierarchical Bell Model, here we show that the use of hierarchical structures leads to an extended physical dimension in the material design space that resolves the conflict between disparate material properties such as strength and robustness, a limitation faced by many synthetic materials. We report materiomics studies in which we combine a large number of alpha-helical elements in all possible hierarchical combinations and measure their performance in the strength-robustness space while keeping the total material use constant. We find that for a large number of constitutive elements, most random structural combinations of elements (> 98%) lead to either high strength or high robustness, reflecting the so-called banana-curve performance in which strength and robustness are mutually exclusive properties. This banana-curve type behavior is common to most engineered materials. In contrast, for few, very specific types of combinations of the elements in hierarchies (< 2%) it is possible to maintain high strength at high robustness levels. This behavior is reminiscent of naturally observed material performance in biological materials, suggesting that the existence of particular hierarchical structures facilitates a fundamental change of the material performance. The results suggest that biological materials may have developed under evolutionary pressure to yield materials with multiple objectives, such as high strength and high robustness, a trait that can be achieved by utilization of hierarchical structures. Our results indicate that both the formation of hierarchies and the assembly of specific hierarchical structures play a crucial role in achieving these mechanical traits. Our findings may enable the development of self-assembled de novo bioinspired nanomaterials based on peptide and protein building blocks.

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Wood and Paper as Materials for the 21st Century

MRS Proceedings ◽

10.1557/proc-1187-kk04-06 ◽

2009 ◽

Vol 1187 ◽

Cited By ~ 1

Author(s):

Philip Jones ◽

Theodore H Wegner

Keyword(s):

Self Assembly ◽

Hierarchical Structures ◽

High Strength ◽

Forest Products ◽

Building Blocks ◽

Forest Products Industry ◽

Strength Performance ◽

New Science ◽

And Performance ◽

Long Fibers

AbstractWood and paper are ubiquitous in societies around the world and are largely taken for granted as part of traditional industries with no new science to learn. Many of the technologies used in the forest products industry have been gained empirically through experience. The complexities of wood are now yielding to newer tools and we are beginning to see how the mechanical, optical and other physical properties of wood are related to hierarchical structures based on 2 to 10 nm diameter several hundred nm long fibers of nanocrystalline cellulose (NCC). The liberation of these NCC’s is allowing their re-assembly into remarkably strong structures. Examples will be given of the nature of these building blocks and structures assembled from them. Examples will include nanocomposites as well as very high strength “paper”. Paper is another example of a process whereby nanofibrils are released and then re-assembled with the use of “retention, drainage and formation aides” to make substrates we call paper with remarkable strength to weight performance. Other disciplines call this process “self-assembly” and the “aids” as necessary surfactants and additives to control structure and performance. Glossy magazine papers, for example, have approximately 10 micron thick coatings of white minerals and latex binders which are increasingly of nano dimensions. The coatings are assembled in structures to provide optical barrier performance (opacity) as well as controlled ink interaction with the necessary strength to survive printing and handling. These coatings are frequently similar in structure to seashells and, from this knowledge, progress has been made in understanding the mechanisms at play in achieving higher strength coatings. More recently kaolin clays have been introduced with mean crystal thicknesses in the range 20 to 40 nm instead of the usual 100 to 140 nm. These clays show useful strength performance and represent what may be called pragmatic nanoclays. Novel chemistries based on biomimetic learnings are emerging to displace the conventional starch or latex binders. Examples will be given of protocols for moving toward higher strength systems.

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De novo design of self-assembling helical protein filaments

Science ◽

10.1126/science.aau3775 ◽

2018 ◽

Vol 362 (6415) ◽

pp. 705-709 ◽

Cited By ~ 48

Author(s):

Hao Shen ◽

Jorge A. Fallas ◽

Eric Lynch ◽

William Sheffler ◽

Bradley Parry ◽

...

Keyword(s):

De Novo ◽

Computational Design ◽

Building Blocks ◽

Repeat Units ◽

Self Assembling ◽

Wide Range ◽

Helical Protein ◽

Monomeric Proteins

We describe a general computational approach to designing self-assembling helical filaments from monomeric proteins and use this approach to design proteins that assemble into micrometer-scale filaments with a wide range of geometries in vivo and in vitro. Cryo–electron microscopy structures of six designs are close to the computational design models. The filament building blocks are idealized repeat proteins, and thus the diameter of the filaments can be systematically tuned by varying the number of repeat units. The assembly and disassembly of the filaments can be controlled by engineered anchor and capping units built from monomers lacking one of the interaction surfaces. The ability to generate dynamic, highly ordered structures that span micrometers from protein monomers opens up possibilities for the fabrication of new multiscale metamaterials.

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Design of complicated all-α protein structures

10.1101/2021.07.14.449347 ◽

2021 ◽

Author(s):

Koya Sakuma ◽

Naohiro Kobayashi ◽

Toshihiko Sugiki ◽

Toshio Nagashima ◽

Toshimichi Fujiwara ◽

...

Keyword(s):

De Novo ◽

Protein Structures ◽

Building Blocks ◽

Helical Structures ◽

Helix Loop Helix ◽

Naturally Occurring ◽

Wide Range ◽

Helical Protein ◽

Helical Proteins ◽

The Universe

A wide range of de novo protein structure designs have been achieved, but the complexity of naturally occurring protein structures is still far beyond these designs. To expand the diversity and complexity of de novo designed protein structures, we sought to develop a method for designing 'difficult-to-describe' α-helical protein structures composed of irregularly aligned α-helices, such as globins. Backbone structure libraries consisting of a myriad of α-helical structures with 5- or 6- helices were generated by combining 18 helix-loop-helix motifs and canonical α-helices, and five distinct topologies were selected for de novo design. The designs were found to be monomeric with high thermal stability in solution and fold into the target topologies with atomic accuracy. This study demonstrated that complicated α-helical proteins are created using typical building blocks. The method we developed would enable us to explore the universe of protein structures for designing novel functional proteins.

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Biomimetic Ceramics and Composites

MRS Bulletin ◽

10.1557/s0883769400046467 ◽

1992 ◽

Vol 17 (10) ◽

pp. 37-40 ◽

Cited By ~ 57

Author(s):

Paul Calvert

Keyword(s):

Composite Structures ◽

Tooth Enamel ◽

Weight Ratio ◽

High Strength ◽

Biological Materials ◽

Structure And Function ◽

Synthetic Materials ◽

Complex Architectures ◽

And Function ◽

Synthetic Work

An obvious parallel of structure and function exists between a rhinoceros and a tank, and between a beetle shell and the skin of an aircraft. We can also draw comparisons at the microstructural level between these biological and synthetic materials. Significant differences also exist, however, and the rigid biological materials such as bone and shell have much to teach us. In particular, they are distinctly composite structures. Although they bear loads in much the same way as synthetic composites or ceramics, they have far more complex architectures.The goal in considering the group of mineralized biological materials as described, for example, in the article by Fink et al. in this issue, and in devising modifications of them, which is the focus of this article and of Mann's, is to learn to devise arrangements of synthetic materials that work more efficiently than the homogeneous substances of simple composites that we use now. In addition to designing better microstructural arrangements we may also learn, again by analogy to the biological materials, how best to process these structures and how to recycle them after use.Biological structural materials are optimized for their high strength- or stiffness-to-weight ratio. Achieving this in synthetic materials for nonbiological application, for example in cars and airplanes, would be of obvious value. Our own interest here has focused on cuticle and bone as models for our synthetic work. Another property of biomineralized materials, for example biological ceramics, is their increased toughness. In this case we will discuss tooth enamel mimicking.

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Supramolecular assembly of protein building blocks: from folding to function

Nano Convergence ◽

10.1186/s40580-021-00294-3 ◽

2022 ◽

Vol 9 (1) ◽

Author(s):

Nam Hyeong Kim ◽

Hojae Choi ◽

Zafar Muhammad Shahzad ◽

Heesoo Ki ◽

Jaekyoung Lee ◽

...

Keyword(s):

Self Assembly ◽

De Novo ◽

Complex Structure ◽

Supramolecular Assembly ◽

Hierarchical Structures ◽

Computational Design ◽

Building Blocks ◽

Biological Phenomena ◽

Living Things ◽

Protein Interfaces

AbstractSeveral phenomena occurring throughout the life of living things start and end with proteins. Various proteins form one complex structure to control detailed reactions. In contrast, one protein forms various structures and implements other biological phenomena depending on the situation. The basic principle that forms these hierarchical structures is protein self-assembly. A single building block is sufficient to create homogeneous structures with complex shapes, such as rings, filaments, or containers. These assemblies are widely used in biology as they enable multivalent binding, ultra-sensitive regulation, and compartmentalization. Moreover, with advances in the computational design of protein folding and protein–protein interfaces, considerable progress has recently been made in the de novo design of protein assemblies. Our review presents a description of the components of supramolecular protein assembly and their application in understanding biological phenomena to therapeutics.

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Biomimetic materials: An introduction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100129735 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1020-1021 ◽

Cited By ~ 1

Author(s):

M. Sarikaya ◽

J. T. Staley ◽

I. A. Aksay

Keyword(s):

Self Assembly ◽

Structural Control ◽

Hierarchical Structures ◽

Ceramic Composites ◽

Advanced Materials ◽

Length Scale ◽

Spider Webs ◽

Biomimetic Materials ◽

Synthetic Materials ◽

All Ceramic

Biomimetics is an area of research in which the analysis of structures and functions of natural materials provide a source of inspiration for design and processing concepts for novel synthetic materials. Through biomimetics, it may be possible to establish structural control on a continuous length scale, resulting in superior structures able to withstand the requirements placed upon advanced materials. It is well recognized that biological systems efficiently produce complex and hierarchical structures on the molecular, micrometer, and macro scales with unique properties, and with greater structural control than is possible with synthetic materials. The dynamism of these systems allows the collection and transport of constituents; the nucleation, configuration, and growth of new structures by self-assembly; and the repair and replacement of old and damaged components. These materials include all-organic components such as spider webs and insect cuticles (Fig. 1); inorganic-organic composites, such as seashells (Fig. 2) and bones; all-ceramic composites, such as sea urchin teeth, spines, and other skeletal units (Fig. 3); and inorganic ultrafine magnetic and semiconducting particles produced by bacteria and algae, respectively (Fig. 4).

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Bacterial cellulose spheroids as building blocks for 3D and patterned living materials and for regeneration

Nature Communications ◽

10.1038/s41467-021-25350-8 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Joaquin Caro-Astorga ◽

Kenneth T. Walker ◽

Natalia Herrera ◽

Koon-Yang Lee ◽

Tom Ellis

Keyword(s):

Bacterial Cellulose ◽

Building Blocks ◽

Genetically Engineered ◽

High Yield ◽

Synthetic Materials ◽

Chemical Inputs ◽

First Time ◽

3D Shapes ◽

Promising Avenue ◽

Living Materials

AbstractEngineered living materials (ELMs) based on bacterial cellulose (BC) offer a promising avenue for cheap-to-produce materials that can be programmed with genetically encoded functionalities. Here we explore how ELMs can be fabricated in a modular fashion from millimetre-scale biofilm spheroids grown from shaking cultures of Komagataeibacter rhaeticus. Here we define a reproducible protocol to produce BC spheroids with the high yield bacterial cellulose producer K. rhaeticus and demonstrate for the first time their potential for their use as building blocks to grow ELMs in 3D shapes. Using genetically engineered K. rhaeticus, we produce functionalized BC spheroids and use these to make and grow patterned BC-based ELMs that signal within a material and can sense and report on chemical inputs. We also investigate the use of BC spheroids as a method to regenerate damaged BC materials and as a way to fuse together smaller material sections of cellulose and synthetic materials into a larger piece. This work improves our understanding of BC spheroid formation and showcases their great potential for fabricating, patterning and repairing ELMs based on the promising biomaterial of bacterial cellulose.

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