Previously, we designed and constructed a hybrid of the mussel adhesive protein (MAP) fp-151, which is a fusion protein with six type 1 (fp-1) decapeptide repeats at each type 5 (fp-5) terminus. Through various cell-adhesion analyses, we previously demonstrated that fp-151 has the potential to be used as a cell or tissue bioadhesive. In the present study, to improve the cell-adhesion properties of fp-151, we designed a new cell-adhesive protein, fp-151-RGD, which is a fusion with the GRGDSP residues, a RGD peptide sequence that has previously been identified at
the cell-attachment site of fibronectin, at the C-terminus of fp-151. Although recombinant fp-151-RGD maintained the advantages associated with fp-151, such as a high production yield in Escherichia coli and simple purification, it showed superior spreading ability, which is important for cell proliferation under serum-free conditions, as well as better cell-adhesion ability compared with other commercially produced cell-adhesion materials such as poly-L-lysine (PLL) and the naturally extracted MAP mixture Cell-Tak.