Patent ID: 8389676

Claim:
A biotinylation peptide comprising: a non-naturally occurring peptide sequence of 13 to 50 amino acid residues comprising the amino acid sequence: Xaa.sub.0 Xaa.sub.1 Xaa.sub.2 Xaa.sub.2.5, Xaa.sub.3 Xaa.sub.4 Xaa.sub.5 Xaa.sub.6 Lys Xaa.sub.7 Xaa.sub.8 Xaa.sub.9 Xaa.sub.10, wherein a) Xaa.sub.0 is Ile; Xaa.sub.1 is any amino acid; Xaa.sub.2 is any amino acid other than Val, Ile, Trp, Phe, or Tyr; Xaa.sub.2.5 is Leu, Ile, or Phe; Xaa.sub.3 is Phe, Leu, or Val; Xaa.sub.4 is Glu, Asp, His, Asn, or Ser; Xaa.sub.5 is Ala, Gly, Ser, or Thr; Xaa.sub.6 is Gln or Met; Xaa.sub.7 is Ile, Met, or Val; Xaa.sub.8 is Glu, Leu, Val, Tyr, or Ile; Xaa.sub.9 is Trp, Tyr, Val, Phe, Leu, or Ile; and Xaa.sub.10 is any amino acid other than Asp or Glu (SEQ ID NO:13), b) Xaa.sub.0 is Leu or Ile; Xaa.sub.1 is any amino acid; Xaa.sub.2 is Leu; Xaa.sub.2.5 is Leu, Ile, or Phe; Xaa.sub.3 is Phe, Leu, or Val; Xaa.sub.4 is Glu, Asp, His, Asn, or Ser; Xaa.sub.5 is Ala, Gly, Ser, or Thr; Xaa.sub.6 is Gln or Met; Xaa.sub.7 is Ile, Met, or Val; Xaa.sub.8 is Glu, Leu, Val, Tyr, or Ile; Xaa.sub.9 is Trp, Tyr, Val, Phe, Leu, or Ile; and Xaa.sub.10 is any amino acid other than Asp or Glu (SEQ ID NO:14), c) Xaa.sub.0 is Leu or Ile; Xaa.sub.1 is any amino acid; Xaa.sub.2 is any amino acid other than Val, Ile, Trp, Phe, or Tyr; Xaa.sub.2.5 is Leu or Phe; Xaa.sub.3 is Phe, Leu, or Val; Xaa.sub.4 is Glu, Asp, His, Asn, or Ser; Xaa.sub.5 is Ala, Gly, Ser, or Thr; Xaa.sub.6 is Gln or Met; Xaa.sub.7 is Ile, Met, or Val; Xaa.sub.8 is Glu, Leu, Val, Tyr, or Ile; Xaa.sub.9 is Trp, Tyr, Val, Phe, Leu, or Ile; and Xaa.sub.10 is any amino acid other than Asp or Glu (SEQ ID NO:15), d) Xaa.sub.0 is Leu or Ile; Xaa.sub.1 is any amino acid; Xaa.sub.2 is any amino acid other than Val, Ile, Trp, Phe, or Tyr; Xaa.sub.2.5 is Leu, Ile, or Phe; Xaa.sub.3 is Val; Xaa.sub.4 is Glu, Asp, His, Asn, or Ser; Xaa.sub.5 is Ala, Gly, Ser, or Thr; Xaa.sub.6 is Gln or Met; Xaa.sub.7 is Ile, Met, or Val; Xaa.sub.8 is Glu, Leu, Val, Tyr, or Ile; Xaa.sub.9 is Trp, Tyr, Val, Phe, Leu, or Ile; and Xaa.sub.10 is any amino acid other than Asp or Glu (SEQ ID NO:16), or e) Xaa.sub.0 is Leu or Ile; Xaa.sub.1 is any amino acid; Xaa.sub.2 is any amino acid other than Val, Ile, Trp, Phe, or Tyr; Xaa.sub.2.5 is Leu, Ile, or Phe; Xaa.sub.3 is Phe, Leu, or Val; Xaa.sub.4 is His, Asn, or Ser; Xaa.sub.5 is Ala, Gly, Ser, or Thr; Xaa.sub.6 is Gln or Met; Xaa.sub.7 is Ile, Met, or Val; Xaa.sub.8 is Glu, Leu, Val, Tyr, or Ile; Xaa.sub.9 is Trp, Tyr, Val, Phe, Leu, or Ile; and Xaa.sub.10 is any amino acid other than Asp or Glu (SEQ ID NO:17); and wherein said biotinylation peptide is capable of being biotinylated by a biotin ligase at the lysine residue adjacent to Xaa.sub.6.