Investigations using photo affinity labeled analogues confirm the binding between sCD4 and the PND of HIV-1, MN.
In previous studies we demonstrated that a synthetic peptide corresponding to the sequence in the (307-330) region of the gp120 principal neutralizing domain of the HIV-1 MN strain is able to bind sCD4 in an affinity chromatography assay and to enhance CD4 expression, CD4 affinity for gp120, and HIV-1 infection. This paper describes a photo affinity labeling experiment, designed to confirm the gp120 peptide-CD4 interaction and to locate the binding site of the synthetic peptide on the CD4 molecule. To this end two specifically marked analogues of the peptide patterned on the (307-330) region of HIV-MN-gp120, in which the TyrI residue is replaced with Phe(p-N3) or Phe(p-NO2), have been synthesized. Irradiation of CD4 solutions in the presence of both analogues produced a new component, the mass value of which confirms the formation of a covalent bond between the peptide and the protein.
Dettin
M
M
Department of Chemical Process Engineering, University of Padua, Italy.
Scarinci
C
C
Seraglia
R
R
Di Bello
C
C
D001665:Binding Sites; D015704:CD4 Antigens / Q000378:metabolism*; D015699:HIV Envelope Protein gp120 / Q000378:metabolism*; D015497:HIV-1 / Q000145:classification / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism*; D019920:Photoaffinity Labels; D011485:Protein Binding; D012995:Solubility
D015704:CD4 Antigens; D015699:HIV Envelope Protein gp120; C059762:HIV envelope protein gp120 (305-321); D010446:Peptide Fragments; D019920:Photoaffinity Labels