The Effect of Oxidation in Mussel Protein Adhesion

Tuesday, November 9, 2010: 10:00 AM
Grand Ballroom J (Salt Palace Convention Center)
Jing Yu1, Wei Wei2, Eric W. Danner3, Jacob N. Israelachvili1 and J. Herbert Waite3, (1)Chemical Engineering, University of California, Santa Barbara, Santa Barbara, CA, (2)Materials Research Laboratory, University of California, Santa Barbara, Santa Barbara, CA, (3)Department of Molecular, Cell & Developmental Biology, University of California, Santa Barbara, Santa Barbara, CA

Underwater adhesion in the byssus of marine mussels relies on mussel foot proteins (mfps) rich in the catecholic amino acid 3, 4-dihydroxyphenylalanine (dopa). Dopa is a perplexing adhesive adaptation: as a side-chain in synthetic polymers, dopa is capable of strong interactions with a variety of surfaces, but its susceptibility to oxidation often renders it unreliable for adhesion. Using the Surface Forces Apparatus (SFA) technique, we demonstrate that the adhesion of mussel foot protein 3 (mfp-3) to mica is closely coupled to dopa redox and pH. Raising the pH from 3 to 7.5 decreases the adhesion energy of mfp-3 on mica by a factor of 20 and appears to be driven by the pH-dependent oxidation of dopa in mfp-3. Adding an artifical oxidant, periodate, at pH 3 can also decrease the adhesion of mfp-3 to mica. Our results demonstrate the importance of the oxidation of dopa in mussel protein adhesion.

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See more of this Session: Biomolecules at Interfaces
See more of this Group/Topical: Materials Engineering and Sciences Division