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Mussels attach to a variety of substrates in sea water, an environment that is ordinarily hostile to adhesion. Previous research has shown that the catechol group found on 3,4-dihydroxyphenylalanine (dopa), an amino acid found in the mussel foot, is responsible for mussel adhesion. The catechol moiety is highly susceptible to oxidation and forms a quinone that cannot participate in adhesion. This oxidation process is reversed by cysteine, another amino acid found in mussels. We believe that the dopa quinone may also tautomerize to produce α,β-dehydro-dopa, a compound that can still participate in adhesion. The tautomerization could serve as a chemical pathway to keep catechol groups present in mussel plaques despite their oxidative environment. To gather evidence for this hypothesis, we are interested in determining whether α,β -dehydro-dopa has an impact on adhesion in mussels. Two model compounds, representative of dehydro-dopa and dopa, were studied: caffeic acid and 3,4-dihydroxyhydrocinnamic acid (DHC), respectively. We studied each compounds' response to cysteine using cyclic voltammetry. We found that compared to DHC, caffeic acid reacts more readily with cysteine. If dehydro-dopa is present in mussels, cysteine may be more efficient at reducing dehydro-dopa quinones than dopa quinones, an advantageous situation for mussels. To compare the adhesive capabilities of DHC and caffeic acid, we made adhesives using coacervates and a chelating agent in addition to a model compound. We measured the force required to pull apart metal plates glued with the adhesive, and we did not find a difference in the adhesive strengths of caffeic acid and DHC.