Recombinant mussel protein Pvfp-5beta: a potential tissue bioadhesive

During their lifecycle, many marine organisms rely on natural
adhesives to attach to wet surfaces for movement and self-defense
in aqueous tidal environments. Adhesive proteins from
mussels are biocompatible and elicit only minimal immune
responses in humans. Therefore these proteins have received
increased attention for their potential applications in medicine,
biomaterials, and biotechnology. The Asian green mussel Perna
viridis secretes several byssal plaque proteins, molecules that
help anchoring the mussel to surfaces. Among these proteins,
protein-5 (Pvfp-5) initiates interactions with the substrate,
displacing interfacial water molecules before binding to the
surface. Here, we established the first recombinant expression
in Escherichia coli of Pvfp-5. We characterized recombinant
Pvfp-5, finding that despite displaying a CD spectrum
consistent with features of a random coil, the protein is
correctly folded as indicated by MS and NMR analyses.
Pvfp-5 folds as a -sheet-rich protein as expected for an
epidermal growth factor-like module. We examined the
effects of Pvfp-5 on cell viability and adhesion capacity in
NIH-3T3 and HeLa cell lines, revealing that Pvfp-5 has no
cytotoxic effects at the protein concentrations used and provides
good cell-adhesion strength on both glass and plastic
plates. Our findings suggest that the adhesive properties of
recombinant Pvfp-5 make it an efficient surface-coating
material, potentially suitable for biomedical applications
including regeneration of damaged tissues.