Specificity of Amaranthus leucocarpus syn. hypocondriacus lectin for O-glycopeptides
Por:
Hernández P., Tetaert D., Vergoten G., Debray H., Del Carmen Jimenez M., Fernández G., Agundis C., Degand P., Zenteno E.
Publicada:
1 ene 2004
Resumen:
Amaranthus leucocarpus syn. hypochondriacus lectin (ALL) has been shown to be specific for N-acetyl-d-galactosamine (GalNAc). In this work, we determined a value of 1.0×10 -2 M for the association constant of ALL for GalNAc, calculated using fluorescence spectroscopy assays. Using neoglycopeptides obtained by in vitro O-glycosylation, we determined the main features of O-glycopeptides recognized by ALL using molecular dynamics simulations, capillary electrophoresis, and ELISA. Neo-glycopeptides were obtained by in vitro O-glycosylation reaction using microsomal preparations of murine thymocytes, human gastric fundus and colonic mucosa. ELISA assays were performed with peroxidase-labeled murine monoclonal IgG2, ? light chain (5D4) antibodies against ALL. Among the in vitro neoglycopeptides, only those of TTSAPTTS containing GalNAc at Thr in #2 and #6 reacted with ALL. Neither the TTSAPTTS glycopeptide, containing a unique GalNAc residue at Thr in #2, nor others (with more than two GalNAc residues) interacted with the lectin. Computational docking assays of the lower energy conformers for interactions between glycopeptides and lectins confirmed that ALL recognized GalNAc residues when they are spaced out in glycan structures, whereas GalNAc residues arranged in clusters prevented interaction with the lectin, indicating that ALL is specific for a special GalNAc-containing motif found in different O-glycoproteins. © 2004 Elsevier B.V. All rights reserved.
Filiaciones:
Hernández P.:
Departamento de Bioquímica, Inst. Nac. de Enferm. Respiratorias, Tlalpan, D.F., 14080, Mexico, Mexico
Ctro. Invest. Medicas-Biol. Fac. M., Univ. Auton. del Estado de Oaxaca, Benito Juarez, 68020 Oaxaca, Mex
Tetaert D.:
Inst. Natl. S. la Rech. Med. U 560, Les Mucines Epitheliales, Gene Fonction, 59045 Lille, France, France
Vergoten G.:
Unité Mixte de Recherche 8576, Glycobiologie Struct. Fonct. U., 59655 Villeneuve d'Ascq, France, France
Debray H.:
Unité Mixte de Recherche 8576, Glycobiologie Struct. Fonct. U., 59655 Villeneuve d'Ascq, France, France
Del Carmen Jimenez M.:
Ctro. Invest. Medicas-Biol. Fac. M., Univ. Auton. del Estado de Oaxaca, Benito Juarez, 68020 Oaxaca, Mex
Fernández G.:
Laboratorio de Inmunología, Departamento de Bioquímica, Fac. Med., UNAM, P.O. B., Mexico
Agundis C.:
Laboratorio de Inmunología, Departamento de Bioquímica, Fac. Med., UNAM, P.O. B., Mexico
Degand P.:
Inst. Natl. S. la Rech. Med. U 560, Les Mucines Epitheliales, Gene Fonction, 59045 Lille, France, France
Zenteno E.:
Laboratorio de Inmunología, Departamento de Bioquímica, Fac. Med., UNAM, P.O. B., Mexico
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