Molecular dynamics simulation of mussel adhesive proteins

Marine organisms like mussels exhibit remarkable underwater adhesion, attributed mainly to the presence of the amino acid 3,4-dihydroxyphenylalanine (L-DOPA) within Mussel Foot Proteins (MFPs). This study aims to perform coarse-grained molecular dynamics (CGMD) simulations of multiple levodopa containing MFPs, using a version of the MARTINI3 force field, specifically designed for disordered biological macromolecules. Particular focus will be placed on understanding the role of protein aggregation and liquid-liquid phase separation (coacervation) in adhesion. The study will investigate how L-DOPA and pH influence protein coacervation and assess the adhesive properties when substituting L-DOPA with chemically similar species, including phenylalanine, tyrosine, and TOPA (3,4,5-trihydroxyphenylalanine). Additionally, this study will explore the effect of adding phosphoserine, a typical amino acid utilized by other organisms such as barnacles, sandcastle worms, and freshwater caddisfly larvae to achieve DOPA-free underwater adhesion. Ultimately, the goal is to elucidate the fundamental principles of wet adhesion at the molecular and mesoscopic level, providing critical insights for developing bio-inspired adhesives applicable in medical surgeries, underwater construction, marine engineering, and wearable biomedical devices.