Production of fusion mussel adhesive fp-353 in Escherichia coli

Mussel adhesive proteins (MAPs) have a potential as environmentally friendly adhesives for use under aqueous conditions. MAPs maybe of particular value in medical applications. We previously reported the functional expression of recombinant foot protein type 5 (fp‐5) and foot protein type 3A (fp‐3A), both of which have significant adhesion abilities, in Escherichia coli. However, these proteins were produced at low levels because of post‐induction cell growth inhibition, and the proteins showed poor post‐purification solubility. Here, we design and produce a new type of recombinant MAP, fp‐353, that is a fusion protein with fp‐3A at each terminus of fp‐5. Because fp‐353 formed inclusion bodies, host cell growth inhibition did not occur. In addition, the solubility of MAP fp‐353 after purification was significantly enhanced, permitting the preparation of a viscous concentrated glue solution for large‐scale adhesion strength measurements. Together with large‐scale cowhide adhesion measurements and cell‐adhesion analyses, we successfully demonstrated that fusion mussel protein fp‐353 has potential as a practical alternative bioadhesive.