Nanomaterials Inspired from the Bacterial Adhesome and Mechanome

This project aims to translate materials design strategies seen in bacterial biofilms to formulate nanocomposites with unforeseen mechanical properties. We seek inspiration from two intriguing features of the microbial world: (1) their adhesive capability arising from intriguing molecular designs as seen in fimbrial adhesins (2) their cohesive strength, arising from extracellular polysaccharides, the most notable of which is nanocellulose fibrils that are comparable to Kevlar in strength and stiffness. The grand challenge in nanocomposite design is to create strong, dissipative interfaces between nanoparticles. Success has been limited in this regard, but matrix-free assembled hairy nanoparticles are a promising route to attain diametric properties such as strength and toughness. What distinguishes our work is the original concept of translating the hallmarks of chaperon usher fimbriae, which are (1) catch bonds, (2) fimbrial extensibility, and (3) relaxation time multiplexity, to polymeric interfaces of self-assembling hairy nanocellulose particles. We envision that successful implementation of this novel design through computational investigations would allow us to reach previously unattainable regions in the Ashby design plot nanocomposites. Our overarching objective is to establish design concepts for stronger and tougher nanocomposites by combining the strategies developed by bacteria to achieve greater adhesion and cohesion in their biofilm matrices. The three aims that will be pursued in light of this overarching objective are: • Aim 1 – Discover strong interface designs through studying fimbrial adhesins • Aim 2 – Investigate the interfacial properties of hairy nanocellulose particles • Aim 3 – Design nanocellulose composites with adhesin-inspired interfaces The proposed work will build upon our pioneering work on molecular and multi-scale modeling of nanocellulose materials, polymer-peptide conjugates, and polymers, leading to new simulation paradigms that will simultaneously benefit several fields including microbiology, mechanics and materials science. The proposed work constitutes an important step forward towards the long-term career goal of the PI, which is aimed at enabling progress towards rapid discovery and design of bioinspired materials by establishing a knowledge base of their physical behavior relevant to applications beyond the biological milieu. By tapping into the exceptional properties of bacterial adhesins, which play a key role in diseases and fouling, and utilizing the strength and stiffness of nanocellulose, we will potentially impact materials used in many Navy relevant applications such as wound healing, biomaterials, adhesives, transparent armor and structural glass. More broadly, our fundamental effort aimed at utilizing bacterial nanocellulose in high performance materials could transform our lives as we envision that nature’s most abundant biopolymer will eventually outperform and replace plastics derived from less sustainable sources. Combination of the aforementioned bioinspired strategies in nanocomposites will require a deeper understanding of the best features of the bacterial adhesome and mechanome, which this project will be able to contribute through computational modeling validated by experiments.