Self-Assembling Peptide and Peptide Gel with High Strength

Abstract

Provide are a peptide gel with practically sufficient mechanical strength and a self-assembling peptide capable of forming the peptide gel. The self-assembling peptide is formed of the following amino acid sequence: a 1 b 1 c 1 b 2 a 2 b 3 db 4 a 3 b 5 c 2 b 6 a 4 where: a 1 to a 4 each represent a basic amino acid residue; b 1 to b 6 each represent an uncharged polar amino acid residue and/or a hydrophobic amino acid residue, provided that at least five thereof each represent a hydrophobic amino acid residue; c 1 and c 2 each represent an acidic amino acid residue; and d represents a hydrophobic amino acid residue.

We claim: 
     
         1 . A self-assembling peptide, comprising an amino acid sequence:
 a 1 b 1 c 1 a 2 b 2 c 2 b 3 db 4 a 3 b 5 c 2 b 6 a 4      
       wherein a 1  to a 4  each represent a basic amino acid residue, 
       b 1  to b 6  each represent at least one amino acid residue selected from the group consisting of a hydrophobic amino acid residue, provided that at least five thereof each represent a hydrophobic amino acid residue, 
       c 1  and c 2  each represent an acidic amino acid residue, and 
       d represents a hydrophobic amino acid residue. 
     
     
         2 . The peptide of  claim 1  wherein all of b 1  to b 6  in the amino acid sequence each represent a hydrophobic amino acid residue. 
     
     
         3 . The peptide of  claim 1  wherein b 1  to b 6  in the amino acid sequence each independently represent an alanine residue, a valine residue, a leucine residue or an isoleucine residue. 
     
     
         4 . The peptide of  claim 1  wherein at least one of b 1  to b 6  in the amino acid sequence represent a leucine residue. 
     
     
         5 . A modified peptide, comprising the peptide of  claim 1 , wherein at least one selected from the group consisting of the N-terminal amino group and the C-terminal carboxyl group is modified, and wherein the modified peptide has a self-assembling ability. 
     
     
         6 . The modified peptide of  claim 5  wherein the at least one of the N-terminal amino group and the C-terminal carboxyl group has added thereto an amino acid sequence comprising RGD. 
     
     
         7 . The modified peptide of  claim 5  wherein the at least one of the N-terminal amino group and the C-terminal carboxyl group has added thereto a protective group. 
     
     
         8 . The modified peptide of  claim 5  wherein the at least one of the N-terminal amino group and the C-terminal carboxyl group has added thereto a sequence selected from the group consisting of: REDV, EILDV, YEKPGSPPREVVPRPRPGV, KNNOKSEPLIGRK, YIGSR, RNIAELLKDI, RYVVLPRPVCFEKGMNYTVR, IKVAV, and PDSGR. 
     
     
         9 . A peptide gel, which is formed from an aqueous solution comprising at least one selected from the group consisting of the peptide of  claim 1  and the modified peptide of  claim 5 .