Premium
A novel peptide designed for sensitization of terbium (III) luminescence
Author(s) -
Clark Ian D.,
Hill Irene,
Sikorska-Walker Marianna,
MacManus John P.,
Szabo Arthur G.
Publication year - 1993
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(93)80381-4
Subject(s) - peptide , luminescence , terbium , cysteine , chemistry , conjugate , residue (chemistry) , chelation , lanthanide , covalent bond , peptide sequence , salicylic acid , combinatorial chemistry , stereochemistry , biochemistry , materials science , inorganic chemistry , organic chemistry , mathematical analysis , ion , mathematics , optoelectronics , gene , enzyme
Several synthetic peptides, modelled from a Ca 2+ ‐binding loop of the EF‐hand family of proteins, were prepared containing cysteine residues. The peptide, GDKNADGFICFEEL, was labelled covalently at the cysteine residue (loop position 9) with iodoacetamidosalicylic acid. This novel conjugate is a metal‐binding loop containing a salicylic acid side chain that could not only chelate Tb 3+ in conjunction with the other chelating groups in the sequence, but could also sensitize Tb 3+ luminescence. The loop had a high Tb 3+ affinity, with stoichiometric binding observed under experimental conditions. The luminescence from the Tb 3+ ‐peptide complex was more than 10‐fold greater than the luminescence reported from a related peptide which contained Trp as the Tb 3+ donor at loop position 7. This peptide has significant potential for use in lanthanide‐based time‐resolved luminescence immunoassays.