[An attempt at clinical applications of adhesive protein from the marine mussel, Mytilus edulis L].

Polyphenolic or adhesive protein (PPP, Mr = 125,000) from the marine mussel Mytilus edulis consists largely of tandemly repeated decapeptide sequence, ala-lys-pro/hyp-ser-tyr/dopa-hyp-hyp-thr-dopa-lys. Because of our interest in better understanding of the mechanism of under water adhesion by this protein, we have attempted to ascertain the adhesiveness of PPP to a cultured chondrocyte. About 90% of the chondrocyte were rapidly attached to the dish coated by PPP within 60 minutes. A protein with 216 amino acids and molecular weight of 24,000 has 20 repeats of decapeptide sequence (20 mer), which designed as a synthetic analogue of proto-PPP. Nearly 44% of tyrosyl group in the 20 mer were converted to dopa which is thought to play an essential role in the adhesive and cohesive properties of the protein by mushroom tyrosinase. The dopa conversion ratios of tyr-5 (-ser-tyr-pro-) and tyr-9 (-thr-tyr-lys) in the decapeptide sequence of the 20 mer were very similar to those of PPP. These findings may contribute to design a new type of adhesives for living tissues.