A de novo structural biopolymer library to predict, design and control the assembly of hierarchically mesostructured materials
Abstract
RESEARCH PROBLEM: In recent decades, many studies on the performance of natural materials have established a foundational link between biopolymers chemistry, structure and function. However, current materials design and fabrication technologies are limited by the wide use of synthetic polymers and traditional top-down fabrication processes, which present challenges for achieving well-defined structural organization, particularly at the nanoscale. Living organisms, on the other hand, attain complex hierarchical material structures by directing the assembly of biomacromolecules in mild conditions, using water-based environments as milieu for fabrication. Building the relationship between natural polymers chemistry, molecular structure, and assembly has become a source of inspiration not only for synthesizing polymeric materials, but also for developing innovative methods of advanced materials nanomanufacturing. TECHNICAL APPROACHES: This research program draws inspiration from the natural assembly process of structural biopolymers to design structural proteins capable of dynamic assembly into hierarchical structures and with tunable properties. The ultimate goal of this proposal is to investigate, predict, and control protein-protein interactions that guide the design and synthesis of de novo structural proteins used for nanofabrication of hierarchically mesostructured materials that can assemble in response to external triggers. In natural structural proteins, a combination of protein-specific, highly repetitive amino acid motifs (HRAAM) and non-repetitive amino acid sequences (NRAAS) orchestrate material assembly via: i) an extensive set of weak interactions spread over a large surface (e.g., silk fibroin), ii) protein folding-recoiling (e.g., tropoelastin), iii) metal coordination (e.g., histidine-rich and polyphenol-rich foot proteins in blue mussel) and iv) enzyme-mediated covalent crosslinking (e.g., inter-fibrillar crosslinking in collagens and elastin). We propose to create a de novo library of synthetic structural proteins consisting of HRAAM and NRAAS. These proteins will be used to predict the fundamental principles underlying structural protein assembly into complex architectures and to fabricate hierarchical mesostructured materials. ANTICIPATED OUTCOME: We will develop a conceptual framework that shows how a combination of weak interactions and metal coordination phenomena can regulate structural protein folding and assembly. We will create an extensive library of unprecedented synthetic structural materials via de novo synthesis. This will enable the nanomanufacturing of programmable materials that (i) assemble in several environments, including seawater, in response to external stimuli (ii) self-heal, (iii) adhere underwater to surfaces with different chemistry ~ including metals and ceramics, (iv) form transparent, flexible, stretchable materials and (v) can be interfaced with the biotic world. IMPACT ON DOD CAPABILITIES: The proposed work will encompass a mechanistic understanding of the composition-structure-function relationship in de novo structural proteins and will enable synthesis of new materials, where protein folding and assembly can be engineered to design dynamically controlled nanostructures relevant to the US Navy. The completion of research tasks 1-5 will be ancillary for the design of unprecedented materials and nanofabrication strategies with foreseen applications in: 1) self-healing materials in seawater, 2) underwater adhesives, 3) maritime shock absorbing materials, and 4) fractionated material, which could impact a wide range of applications of interest to the ONR. APPROVED FOR PUBLIC RELEASE.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 13, 2019
- Source ID
- N000141912317
Entities
People
- Benedetto Marelli
Organizations
- Massachusetts Institute of Technology
- Office of Naval Research
- United States Navy