Inter- and intramolecular adhesion mechanisms of mussel foot proteins

Mussel foot proteins (Mfps) secreted in the byssal plaque of marine mussels are widely researched for their relevance to mussel adhesion in water. As the abundant residue in the amino acid sequences of major adhesive proteins, 3,4-dihydroxyphenylalanine (Dopa) or its catecholic moiety plays a key role in both Mfp binding to surface and cohesive cross-linking of Mfps in byssal plaques. The binding performance of an Mfp significantly depends on the content and redox state of Dopa, whereas the types of interaction vary in line with different surface chemistries and pH conditions. Thorough understanding of mussel adhesion from a molecular perspective is crucial to promote the application of synthetic mussel-bionic adhesives. This article presents a brief review of the research progress on the adhesion mechanisms of Mfps, which further emphasizes the contributions of Dopa-mediated interactions and considers other amino acids and factors. The involved inter- and intramolecular interactions are responsible for not only the diverse adhesion capacities of an adhesive byssal plaque as mussel’s adhesion precursor but also the formation and properties of the plaque structure.