Hemagglutinin-binding peptide
Disclosed is a hemagglutinin-binding peptide producing an anti-influenza virus effect higher than that of existing peptides. Also disclosed are hemagglutinin-binding peptides comprising a polypeptide having any of the following amino acid sequences (i) to (iv): (i) Thr-MeGly-Asp-MePhe-MePhe-Ser-MeSer-His-Tyr-Thr-Val-Pro-Arg (SEQ ID NO: 1); (ii) Arg-Val-Ser-MePhe-Thr-Tyr-MePhe-MeSer-Tyr-Thr-Pro-Ser (SEQ ID NO: 2); (iii) an amino acid sequence with deletions, additions, or substitutions of one or several amino acids in SEQ ID NO: 1 or 2; and (iv) an amino acid sequence having 90% or more sequence identity to that of SEQ ID NO: 1 or 2.
1. A peptide comprising an amino acid sequence (a) having 90% or more sequence identity to that of SEQ ID NO: 2, or (b) represented by the following formula (I):
Xaa 1 -Xaa 2 -Xaa 3 -Xaa 4 -Xaa 5 -Xaa 6 -Xaa 7 -Xaa 8 -Xaa 9 -Xaa 10 -Xaa 11 -Xaa 12 -Xaa 13 (SEQ ID NO: 3) (I)
wherein
Xaa 1 is Ser or Thr,
Xaa 2 is an N-methylamino acid,
Xaa 3 is an arbitrary amino acid,
Xaa 4 is a basic amino acid,
Xaa 5 is Val,
Xaa 6 is a basic amino acid,
Xaa 7 is Tyr,
Xaa 8 is Ser or Thr,
Xaa 9 is Val,
Xaa 10 is MePhe,
Xaa 11 is Asn,
Xaa 12 is MeAla, and
Xaa 13 is Val or Ser.
2. The peptide according to claim 1 , wherein
Xaa 2 is MePhe or MeGly,
Xaa 3 is MeGly or Thr,
Xaa 4 is His, and
Xaa 6 is His or Arg.
3. The peptide according to claim 1 , wherein said Xaa 1 -Xaa 2 -Xaa 3 -Xaa 4 -Xaa 5 -Xaa 6 -Xaa 7 -Xaa 8 -Xaa 9 -Xaa 10 -Xaa 11 -Xaa 12 -Xaa 13 is Ser-MePhe-MeGly-His-Val-His-Tyr-Ser-Val-MePhe-Asn-MeAla-Val (SEQ ID NO: 4) or Thr-MeGly-Thr-His-Val-Arg-Tyr-Thr-Val-MePhe-Asn-MeAla-Ser (SEQ ID NO: 5).
4. The peptide according to claim 1 , wherein said peptide is cyclized.
5. The peptide according to claim 4 , wherein said peptide comprises a chloroacetylated amino acid within 3 amino acids from the N-terminus; and cysteine within 3 amino acids from the C-terminus.
6. The peptide according to claim 4 , wherein said peptide comprises chloroacetyl-Trp at the N-terminus, having Cys at the C-terminus, and is cyclized via a thioether bond therebetween.
7. A pharmaceutical composition comprising the peptide according to claim 1 .
8. An influenza virus detection agent, comprising the peptide according to claim 1 .
9. An influenza virus detection kit, comprising the influenza detection agent according to claim 8 .
10. A method of treating or inhibiting an influenza infection in a subject, which comprises administering to the subject a peptide according to claim 1 .