Abstract: Provided are linkers suitable for preparing a conjugate of a nucleic acid and a peptide as a translation product thereof in a reconstituted cell-free translation system in genotype-phenotype mapping (display methods), said linkers comprising a single-stranded structure region having a side chain base pairing with the base at the 3?-end of an mRNA at one end and a peptidyl acceptor region containing an amino acid attached to an oligo RNA consisting of a nucleotide sequence of ACCA via an ester bond at the other end, characterized in that the ester bond is formed by using an artificial RNA catalyst. Also provided are display methods using [mRNA]-[linker]-[peptide] conjugates assembled via such linkers.

Abstract: [Problem] To provide a guanidine derivative (in particular, an amino acid compound having a 4-guanidino group) which has a low production cost and is less likely to cause the problem of waste liquor, a method for producing the same and an intermediate to be used in the production of the same. [Solution] A compound represented by formula (I), a tautomer thereof, an enantiomer thereof, a pharmaceutically acceptable salt thereof or a pharmaceutically acceptable solvate thereof; a method for producing a compound represented by formula (I), a tautomer thereof, an enantiomer thereof, a pharmaceutically acceptable salt thereof or a pharmaceutically acceptable solvate thereof, said method comprising a mixing step for mixing a compound represented by formula (II) with a compound represented by formula (III); and a compound represented by formula (IV) or formula (V).

Abstract: To provide a peptide, etc., capable of passing through the blood-brain barrier (BBB) by binding to a human transferrin receptor (hTfR). A peptide, etc., having the amino acid sequence shown in SEQ ID NO: 1 (Ala-Val-Phe-Val-Trp-Asn-Tyr-Tyr-Ile-Ile-Ser-Cys) or an amino acid sequence having substitutions, deletions, additions, and/or insertions of 1 to 10 amino acid residues (inclusive) in the amino acid sequence shown in SEQ ID NO: 1.

Abstract: An object of the present invention is to provide a method for producing a peptide with high efficiency, and a method for producing a peptide which comprises the following steps (1) and (2): (1) a step of mixing an N-protected amino acid or an N-protected peptide with a carboxylic acid halide represented by the formula (I) (wherein X represents a halogen atom, R1, R2 and R3 each independently represent an aliphatic hydrocarbon group which may have a substituent, and a total number of the carbon atoms in R1, R2 and R3 is 3 to 40); and (2) a step of mixing the product obtained in the step (1) and a C-protected amino acid or a C-protected peptide is provided.

Abstract: The present invention is to provide a method for producing a peptide containing an N-alkylamino acid, which comprises the following Steps (1) to (3). Step (1): a step of mixing an N-terminal protected amino acid or an N-terminal protected peptide with a carboxylic acid halide or a halogenated alkyl formate; Step (2): a step of mixing an amino acid or a peptide in which the N-terminal and the C-terminal are not protected with a trialkylsilylating agent; and Step (3): a step of mixing the product obtained in Step (1) with the product obtained in Step (2).

Abstract: The invention provides a method for producing a peptide which comprises the following steps (1) and (2): (1) a step of condensing a C-protected amino acid or a C-protected peptide to a C-terminal of an N-protected amino acid or an N-protected peptide represented by the formula (I): wherein Y represents an amino acid in which a C-terminal is unprotected or a peptide in which a C-terminal is unprotected, R1, R2 and R3 each independently represent an aliphatic hydrocarbon group which may have a substituent(s), a total number of the carbon atoms in the R1R2R3Si group is 10 or more, and the R1R2R3SiOC(O) group is bonded to the N-terminal in Y, and (2) a step of removing the protective group at the C-terminal of the peptide obtained in step (1).

Abstract: Provided is a compound that can promote angiogenesis by inhibiting the function of TSP1, and is useful for the treatment or prophylaxis of diseases such as critical limb ischemia.

Abstract: A method for producing a peptide by conducting steps (1) condensing an N-protected amino acid or an N-protected peptide to an N-terminus of a C-protected amino acid or a C-protected peptide represented by formula (II): wherein Y represents an amino acid or a peptide with an unprotected N-terminus; R1, R2 and R3 each independently represent an optionally substituted aliphatic hydrocarbon group, an optionally substituted aromatic hydrocarbon group, or —OR4 (wherein R4 represents an optionally substituted aliphatic or aromatic hydrocarbon group; two of R1, R2 and R3 may form a 5- to 7-membered ring together with the Si atom to which they are bonded; and the R1R2R3Si group has 8 or more carbon atoms and is bonded to a C-terminus of an amino acid or a peptide in Y, and (2) removing the protective group at the N-terminus of the peptide obtained in step (1).

Abstract: An object of the present invention is to provide a method of producing a peptide containing a charged non-proteinogenic amino acid in a cell-free translation system, and the like. The present invention provides a method of producing a peptide containing a charged non-proteinogenic amino acid. It includes a step of expressing a peptide in a cell-free translation system including (i) at least one tRNA to which a non-proteinogenic amino acid having a protecting-group-introduced charged group has been bound and (ii) a nucleic acid that encodes the peptide and contains at least one codon corresponding to an anticodon of the tRNA; and a step of removing the protecting group of the non-proteinogenic amino acid residue contained in the peptide.

Abstract: An object of the present invention is to provide a method for producing a peptide library capable of incorporating an arbitrary number of arbitrary proteinogenic and/or non-proteinogenic amino acids in an arbitrary site. The invention provides a method for producing a peptide library including 1×106 or more kinds of peptides containing amino acids encoded by N1N2N3, including a step of preparing an mRNA library including mRNAs which encode peptides of the peptide library and each contain at least one N1N2N3; and a step of translating each mRNA of the mRNA library in a cell-free translation system added with tRNA containing an anticodon to any one of N1N2N3 codons and charged with an amino acid corresponding to the codon (wherein, N1, N2, and N3 are each independently selected from adenine (A), guanine (G), cytosine (C), and uracil (U) and an arbitrary amino acid is reassigned to each N1N2N3).

Abstract: Provided is a compound that can promote angiogenesis by inhibiting the function of TSP1, and is useful for the treatment or prophylaxis of diseases such as critical limb ischemia.

Abstract: 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.

Abstract: Object of the present invention is to provide a hemagglutinin-binding peptide producing an anti-influenza virus effect higher than that of existing peptides. The present invention provides, for example, a hemagglutinin-binding peptide 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.

Abstract: An object of the present invention is to provide a VEGFR2 inhibitor peptide having high specificity and available at a low cost.

Abstract: An improved method used in selecting a useful protein, peptide, peptide analog by an evolution molecule engineering is provided. A transcription-linker association-translation coupling reaction system characterized by incorporation of a template DNA library to enable a step of forming translation product/linker/mRNA complexes through transcription of a template DNA library to mRNAs, association of mRNAs with linkers, translation of mRNAs, and binding with translation products to be automatically performed in a reaction system, comprising factors necessary for transcription, factors necessary for translation, and linkers.

Abstract: An object of the present invention is to provide a VEGFR2 inhibitor peptide having high specificity and available at a low cost.