Spider Gland Fluids: From Protein-Rich Isotropic Liquid to Insoluble Super Fiber
Abstract
The objective of this research is to elucidate the interactions, mechanisms and chemistries of the spider silk producing process at the molecular level. Our primary focus is to characterize the protein-rich fluid in the major ampullate gland. We have been using a suite of magnetic resonance (NMR and MRI) spectroscopic and X-ray diffraction (XRD) methods to uncover the fundamental molecular mechanisms for converting spider gland fluids to high performance fibers. We have established a method for isotopically (H2/C13/N15) enriching the silk proteins within spider glands and conducted multidimensional, multi-nuclear high-resolution magic angle spinning (HR-MAS) NMR on excised spider glands. Our initial NMR measurements indicate that the silk proteins (MaSp1 and MaSp2) in the major ampullate gland are in a completely unstructured, random coil state prior to fiber formation. In addition, we have found that conditions for converting the isotopic gland fluid to an insoluble fibrous form rich in beta-sheet structure depend on the ratio of the two proteins. Finally, we have succeeded in imaging the major ampullate gland with MRI on a live black widow spider and conducted localized spectroscopy on the gland contents.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 17, 2013
- Accession Number
- ADA590838
Entities
People
- Gregory P. Holland
- Jeffery L Yarger
Organizations
- Arizona State University