Elucidating the natural fabrication process of a high performance biopolymeric fiber

• Applicant: Luca Bertinetti, Ph.D., since 6/2017
• Subject Area: Biological and Biomimetic Chemistry ; Polymer Materials
• Term: from 2017 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 343152969

The mussel byssus is an externally extruded protein-based biological material that has emerged as an important role model for sustainable bio-inspired design of high performance polymers based on its many industrially and biomedically relevant properties (e.g. high toughness, wet adhesion and self-healing capacity). Similar to recent advances in spinning of artificial silks, further breakthroughs in the field of mussel-inspired polymers hinge on the ability to elucidate the natural byssus fabrication process. Previous studies indicate that the byssus is comprised of at least ten different protein building blocks, which are synthesized and stored in an organ known as the mussel foot; yet, almost nothing is known about how these proteins are rapidly assembled into the complex micro- and nano-architectures that define the byssus. This is due to the significant experimental challenges associated with observing and tracking rapid and localized dynamic assembly of protein building blocks in situ. To overcome this challenge and gain critical new information into the byssus fabrication process, I propose an innovative research program employing a synergistic combination of traditional histological methods and cutting-edge spectroscopic imaging. The primary aim is to localize and identify the protein building blocks within the mussel foot and to spatiotemporally track structural and biochemical changes across multiple length scales as proteins transition from fluid precursors to a high performance biopolymeric fiber. In doing so, several key questions will be answered concerning the physicochemical and biological mechanisms controlling the rapid acquisition of complex hierarchical architectures from a fluid secretion of byssus proteins and how this structural order is subsequently locked in and fortified. The fundamental processing steps elucidated through this investigation will have immediate and far-reaching implications for the rapidly growing field of mussel-inspired polymers, as well as for the sustainable manufacture of polymers in general. This project idea stems from a seed grant awarded to young researchers through the DFG SPP-1568, which funded a master project in my group. The preliminary findings are already very promising.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr. Peter Fratzl
• Ehemaliger Antragsteller: Professor Dr. Matthew Harrington, until 5/2017