Expression and functional evaluation of Mytilus galloprovincialis foot protein type 5 (Mgfp-5), the recombinant mussel adhesive protein

Abstract

Mussel contains a variety of adhesion proteins, among which, Mytilus galloprovincialis foot protein type 5 (Mgfp-5) is one of the major proteins required for substrate adhesion. The labor-intensive nature and insufficiency of the extraction process have frequently resulted in very little purified recombinant Mgfp-5. These prompt technologies such as chemical synthesis and genetic engineering are employed to overcome these limitations. In this study, successful expression and purification of the recombinant Mgfp-5 using Escherichia coli BL21 (DE3) and affinity chromatography were reported. Production yield of 12.25% and purity of 96.92%, respectively were observed. The 3,4-dihydroxyphenylalanine (DOPA) content (9.60 pmol/g) and the adhesion (1 116 nN) in modified recombinant Mgfp-5 were 9.32 times and 1.6 times as great as those in the unmodified recombinant Mgfp-5, respectively. Recombinant Mgfp-5 at a concentration of 9.6 mg/L had little cytotoxicity on mouse L-929 fibroblast cells, which was toxic at first in cytotoxicity test, and a concentration of not more than 20 μg/mL would not lead to hemolysis of rabbit erythrocytes. In this case, recombinant Mgfp-5 is biosecure, providing the foundation for Mgfp-5 manufacturing as well as the development of clinical biological adhesive.