Characterizing the Interaction of Mytilus edulis Foot Protein-5 with HY80 Steel
Brooke N Bennett
Mytilus edulis foot protein-5 (Mefp-5), an adhesive protein found in the adhesive plaque of the common blue mussel Mytilus edulis (L), contains high amounts of amino acids L-3,4-dihydroxyphenylalanine (L-dopa, 27 mol%) and lysine (20 mol%). While Mefp-5 has been shown to provide significant corrosion inhibition to a high strength low alloy steel (HY80), the mechanism of inhibition remains elusive. It has been suggested that the close proximity of L-dopa and lysine in Mefp-5 results in a synergy that plays a vital role in the adsorption of the protein to solid substrates. This proposed synergy and its effect on iron oxide films has yet to be elucidated. To characterize how Mefp-5 interacts with the HY80 steel, a variety of analytical spectroscopy techniques were implemented. Solutions of Mefp-5, L-dopa, or lysine dissolved in deionized water, 5% acetic acid, 0.05 M potassium phosphate buffer (pH 5.5), or the same buffer containing mushroom tyrosinase were adsorbed onto HY80 and glass substrates. Raman spectroscopy suggests that adsorbate, solution composition and pH play a role in the type of iron oxide formed and how the protein orients itself on the HY80 surface. At a pH of 5.5, the isoelectric point (pI) of the Fe2O3 oxide suggests the negatively charged oxide surface attracts lysine’s positively charged ε-amine group. Infrared spectroscopy indicates that L-dopa is also intimately involved in the adsorption of the protein on HY80 steel. Overall, the data suggests there is synergy between L-dopa and lysine, where lysine aids in iron availability for L-dopa complexation.
Graduate Research - Graduate
Douglas C Hansen
Primary Advisor's Department
Materials Degradation and Electrochemical Engineering (Research Institute-Materials Engineering)
Stander Symposium poster
"Characterizing the Interaction of Mytilus edulis Foot Protein-5 with HY80 Steel" (2017). Stander Symposium Posters. 970.