Friday, May 12th, 2017
3:00PM – 4:15PM
Chemomechanical Aspects of Mussel Adhesive Proteins and Bioinspired Phenolic Materials
Phillip B Messersmith
Departments of Materials Science and Engineering and Bioengineering
University of California, Berkeley, California
Abstract: A number of marine organisms rely on adhesive secretions for attachment to substrates in wet, turbulent environments. In the case of mussels, adhesion is mediated by the byssus- a remarkably strong and tough tissue comprised of a collection of collagenous protein threads terminally anchored by an adhesive pad. Byssal proteins have very specialized amino acid compositions, likely related to the specific challenges of achieving adhesion in the wet marine environment. One of the unusual residues is 3,4-dihydroxy-L-alanine (DOPA), a phenolic amino acid found in high concentration in proteins found at the byssus-substrate interface where it interacts strongly with organic and inorganic substrates. DOPA is present in lower concentrations away from the interface, where it participates in cross-linking reactions leading to solidification of the adhesive and engages in noncovalent coordination bonds with transition metals (e.g. Fe, Zn and Cu) to strengthen the tissue. In the first part of this talk I will provide an overview of the molecular aspects of mussel adhesion, with an emphasis on bulk and interfacial interactions of DOPA, and the role of metals.
The underlying molecular phenomena of wet biological adhesion can be used to inform the design of synthetic materials with a variety of practical applications. Therefore, in the second half I will describe some of our translational efforts, which include the development of bioinspired polymer surgical adhesives and multifunctional coatings that employ building blocks inspired by mussel adhesive proteins. Most recently, we have developed an interest in chemically related compounds found in plant tissues. Some foods and beverages (tea, wine, chocolate, etc.) derived from plant tissues are rich in polyphenols that have interesting interfacial properties not unlike DOPA. These plant derived compounds are also being used as building blocks for functional materials and I will provide some examples of our work in this area.
Bio: Phillip B. Messersmith is the Class of 1941 Professor in the Departments of Bioengineering and Materials Science and Engineering at UC-Berkeley. He earned his B.S. degree in life sciences in 1985 from the University of Illinois at Urbana, M.S degree in bioengineering from Clemson University, and his Ph.D. degree in materials science and engineering in 1993 from the University of Illinois at Urbana. Previously, Dr. Messersmith was a postdoctoral fellow at Cornell University (1993-1994), and a faculty member at the University of Illinois at Chicago (1994-1997) and Northwestern University (1997-2014). His awards and honors include a MERIT award from the National Institutes of Health, the Langmuir Lecture Award from the American Chemical Society, and the 2013 Clemson Award for Basic Research from the Society for Biomaterials. Dr. Messersmith is a fellow of the American Institute for Medical and Biological Engineering, the Royal Society of Chemistry, and the International Union of Societies of Biomaterials Science and Engineering. The Messersmith research group is interested in understanding structure-processing-property relationships of materials in biological systems, and in using this information to inform the design, synthesis and application of biologically inspired synthetic materials used in a variety of practical applications.