AFRL-AFOSR-VA-TR-2016-0036 Spider Silk: From Protein-rich Gland Fluids to Diverse Biopolymer Fibers

The primary objective of this research is to elucidate the interactions, mechanisms and biochemistry of the spider silk producing process at the molecular level. Our primary focus is to characterize the protein-rich fluid in the various spider silk producing glands. We have been using a battery of magnetic resonance methods including solution and solid-state nuclear magnetic resonance (NMR) and micro imaging (MRI) in combination with wide angle and small angle X-ray diffraction (WAXD and SAXD) techniques at Argonne National Laboratory (ANL) to probe silk protein structure and dynamics prior to and following fiber formation. We have established a number of methods for isotopically (2H/13C/15N) enriching the silk proteins during the course of our AFOSR funding that have allowed us to investigate the structure, dynamics, and organization of spider silk protein within the silk gland and in the final spun fiber with a range of magnetic resonance methods. We successfully developed magnetic resonance imaging (MRI) techniques with localized spectroscopy to probe the silk glands of spiders and map protein structure through out the silk gland. We continue to develop MRI as an in vivo tool for interrogating silk protein structure and dynamics within the different silk glands and have been moving in a direction where we are imaging and conducting localized 1H NMR spectroscopy on silkworms where the internal spinning system is considerably larger compared to spiders. This work has greatly increased our understanding of spider silk and the silk producing process. This information will be useful for scientists trying to reproduce this biologically inspired process in the laboratory. Distribution Statement This is block 12 on the SF298 form. Distribution F Further Dissemination Only as directed by the Controlling Office Explanation for Distribution Statement If this is not approved for public release, please provide a short explanation. E.g., contains proprietary information. Report contains some published and some unpublished work.