title: Binding site on human immunoglobulin G for the affinity ligand HWRGWV.
abstract: Affinity ligand HWRGWV has demonstrated the ability to isolate human immunoglobulin G (hIgG) from mammalian cell culture media. The ligand specifically binds hIgG through its Fc portion. This work shows that deglycosylation of hIgG has no influence on its binding to the HWRGWV ligand and the ligand does not compete with Protein A or Protein G in binding hIgG. It is suggested by the mass spectrometry (MS) data and docking simulation that HWRGWV binds to the pFc portion of hIgG and interacts with the amino acids in the loop Ser383-Asn389 (SNGQPEN) located in the C(H)3 domain. Subsequent modeling has suggested a possible three-dimensional minimized solution structure for the interaction of hIgG and the HWRGWV ligand. The results support the fact that a peptide as small as a hexamer can have specific interactions with large proteins such as hIgG.
authors.affiliation: Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA.
authors.forename: Haiou
authors.initials: H
authors.lastname: Yang
authors.forename: Patrick V
authors.initials: PV
authors.lastname: Gurgel
authors.forename: D Keith
authors.initials: DK
authors.lastname: Williams
authors.forename: Benjamin G
authors.initials: BG
authors.lastname: Bobay
authors.forename: John
authors.initials: J
authors.lastname: Cavanagh
authors.forename: David C
authors.initials: DC
authors.lastname: Muddiman
authors.forename: Ruben G
authors.initials: RG
authors.lastname: Carbonell
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D010450:Endopeptidases / Q000378:metabolism; D006801:Humans; D007141:Immunoglobulin Fc Fragments / Q000378:metabolism; D007074:Immunoglobulin G / Q000737:chemistry / Q000378:metabolism*; D008024:Ligands; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009842:Oligopeptides / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010434:Pepsin A / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D013205:Staphylococcal Protein A / Q000378:metabolism
chemical_list: C029152:G-substrate; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D008024:Ligands; D009419:Nerve Tissue Proteins; D009842:Oligopeptides; D013205:Staphylococcal Protein A; D010450:Endopeptidases; D010434:Pepsin A