Design of peptoid analogue dimers and measure of their affinity for Grb2 SH3 domains.
This paper describes the design of the highest affinity ligands for Grb2 SH3 domains reported so far. These compounds were designed by combining N-alkyl amino acid incorporation in a proline-rich sequence with subsequent dimerization of the peptoid sequence based on structural data and molecular modeling. Optimization of the linker size is discussed, and the N-alkyl amino acid incorporation into both monomeric halves is reported. Because the affinity for Grb2 of the optimized compounds was too high to be measured using the fluorescent modifications that they induce on the Grb2 emission spectrum, a competition assay was developed. In this test, Grb2 is pulled down from a cellular extract by the initial VPPPVPPRRR peptide bound to Sepharose beads. In the presence of competitors, the test quantifies the amount of Grb2 displaced from the beads. It has enabled us to determine a K(i) value in the 10(-10) M range for the highest affinity Grb2 peptoid analogue dimer.
Vidal
M
M
Département de Pharmacochimie Moléculaire et Structurale, INSERM U266, CNRS FRE 2463, UFR des Sciences Pharmaceutiques et Biologiques, 4, Avenue de l'Observatoire, 75270 Paris Cedex 06, France.
Liu
W-Q
WQ
Lenoir
C
C
Salzmann
J
J
Gresh
N
N
Garbay
C
C
D048868:Adaptor Proteins, Signal Transducing; D000478:Alkylation; D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D006224:Cricetinae; D019281:Dimerization; D051380:GRB2 Adaptor Protein; D006801:Humans; D008969:Molecular Sequence Data; D034444:Peptoids / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism*; D011392:Proline / Q000737:chemistry; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D018909:src Homology Domains / Q000187:drug effects
D048868:Adaptor Proteins, Signal Transducing; D051380:GRB2 Adaptor Protein; C495948:GRB2 protein, human; D034444:Peptoids; D011506:Proteins; D011392:Proline