Purification of recombinant proteins fused to multiple epitopes

A polypeptide for use in purifying a target peptide, said polypeptide comprising the sequence

• X20-(D-Y-K-X2-X3-D)n-X5-(D-Y-K-X7-X8-D-X9-K)-X21
• where:
• D, Y, K are their representative amino acids;
• X20 and X21 are independently hydrogen or a bond;
• each X2, X3, X7 and X8 is independently an amino acid residue selected from the group consisting of naturally occurring aromatic amino acid residues and naturally occurring hydrophilic amino acid residues;
• X5 is a bond, resulting in the linking sequence being immediately adjacent to said multiple copies of the antigenic domain, or a spacer domain, said spacer domain comprising at least one naturally occurring amino acid residue or a combination of multiple or alternating histidine residues, said combination comprising His-Gly-His, or —(His—X)m—, wherein m is 1 to 6 and X is selected from the group consisting of Gly, His, Tyr, Trp, Val, Leu, Ser, Lys, Phe, Met, Ala, Glu, Ile, Thr, Asp, Asn, Gln, Arg, Cys, and Pro;
• X9 is a bond or an aspartate residue;
• and
• n is at least 2.

A polypeptide for use in purifying a target peptide, said polypeptide comprising the sequence

• X20-X10-(D-Y-K-X2-X3-D)n-X5-(D-Y-K-X7-X8-D-X9-K)-X21
• where:
• D, Y, and K are their representative amino acids;
• X20 and X21 are independently hydrogen or a bond;
• X10 is a bond, any naturally occurring amino acid residue, or a methionine residue;
• each X2, X3, X7 and X8 is independently an amino acid residue selected from the group consisting of naturally occurring aromatic amino acid residues and naturally occurring hydrophilic amino acid residues;
• X5 is a bond, resulting in the linking sequence being immediately adjacent to said multiple copies of the antigenic domain, or a spacer domain, said spacer domain comprising at least one naturally occurring amino acid residue or a combination of multiple or alternating histidine residues, said combination comprising His-Gly-His, or —(His—X)m—, wherein m is 1 to 6 and X is selected from the group consisting of Gly, His, Tyr, Trp, Val, Leu, Ser, Lys, Phe, Met, Ala, Glu, Ile, Thr, Asp, Asn, Gln, Arg, Cys, and Pro;
• X9 is a bond or an aspartate residue;
• and
• n is at least 2.

A polypeptide for use in purifying a target peptide, said polypeptide comprising the sequence

• X20-(D-X11-Y-X12-X13)n-X14-(D-X11-Y-X12-X13-D-X15-K)-X21
• where:
• D, Y and K are their representative amino acids;
• X20 and X21 are independently hydrogen or a bond;
• each X11 is a bond, any naturally occurring amino acid residue, or a leucine residue;
• each X12 is an amino acid selected from the group consisting of naturally occurring aromatic amino acid residues and naturally occurring hydrophilic amino acid residues;
• each X13 is a bond or at least one amino acid selected from the group consisting of naturally occurring aromatic amino acid residues and naturally occurring hydrophilic amino acid residues;
• X14 is a bond, resulting in the linking sequence being immediately adjacent to said multiple copies of the antigenic domain, or a spacer domain, said spacer domain comprising at least one naturally occurring amino acid residue or a combination of multiple or alternating histidine residues, said combination comprising His-Gly-His, or —(His—X)m—, wherein m is 1 to 6 and X is selected from the group consisting of Gly, His, Tyr, Trp, Val, Leu, Ser, Lys, Phe, Met, Ala, Glu, Ile, Thr, Asp, Asn, Gln, Arg, Cys, and Pro;
• X15 is a bond or an aspartate residue;
• and
• n is at least 2.

A polypeptide for use in purifying a target peptide, said polypeptide comprising the sequence

• X20-X10-(X1-Y-K-X2-X3-D-X4)n-X5-(X1-Y-K-X7-X8-D-X9-K) -X21
• where:
• D, Y and K are their representative amino acids;
• X20 and X21 are independently hydrogen or a bond;
• X10 is a bond, any naturally occurring amino acid residue, or a methionine residue;
• each X1 and X4 is independently a bond or at least one amino acid residue selected from the group consisting of naturally occurring aromatic amino acid residues and naturally occurring hydrophilic amino acid residues;
• each X2, X3, X7 and X8 is independently an amino acid residue selected from the group consisting of naturally occurring aromatic amino acid residues and naturally occurring hydrophilic amino acid residues;
• X5 is a bond, resulting in the linking sequence being immediately adjacent to said multiple copies of the antigenic domain, or a spacer domain, said spacer domain comprising at least one naturally occurring amino acid residue or a combination of multiple or alternating histidine residues, said combination comprising His-Gly-His, or —(His—X)m—, wherein m is 1 to 6 and X is selected from the group consisting of Gly, His, Tyr, Trp, Val, Leu, Ser, Lys, Phe, Met, Ala, Glu, Ile, Thr, Asp, Asn, Gln, Arg, Cys, and Pro;
• X9 is a bond or an aspartate residue;
• and
• n is at least 2.