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A glycopeptide in complex with MHC class I uses the GalNAc residue as an anchor.

ABSTRACT: Peptides bind MHC class I molecules by anchoring hydrophobic side chains into pockets in the peptide binding groove. Here, we report an immunogenic (in vitro and in vivo) MUC1 glycopeptide (MUC1-8-5GalNAc) bound to H-2Kb, fully crossreactive with the nonglycosylated variant. Molecular modeling showed that the central P5-Thr-GalNAc residue points into the C pocket and forms van der Waals and hydrogen bond interactions with the MHC class I. As predicted, GalNAc, a modified peptide carrying an additional anchor in the central C anchor pocket, increased the affinity by approximately 100-fold compared with the native low-affinity peptide (MUC1-8). The findings demonstrate that glycopeptides associated with MHC class I molecules can use GalNAc to anchor the peptide in the groove and enable high-affinity binding.

SUBMITTER: Apostolopoulos V

PROVIDER: S-EPMC299892 | biostudies-literature | 2003 Dec

REPOSITORIES: biostudies-literature

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A glycopeptide in complex with MHC class I uses the GalNAc residue as an anchor.

Apostolopoulos Vasso V Yuriev Elizabeth E Ramsland Paul A PA Halton Jodie J Osinski Carla C Li Wenjun W Plebanski Magdalena M Paulsen Hans H McKenzie Ian F C IF

Proceedings of the National Academy of Sciences of the United States of America 20031201 25

Peptides bind MHC class I molecules by anchoring hydrophobic side chains into pockets in the peptide binding groove. Here, we report an immunogenic (in vitro and in vivo) MUC1 glycopeptide (MUC1-8-5GalNAc) bound to H-2Kb, fully crossreactive with the nonglycosylated variant. Molecular modeling showed that the central P5-Thr-GalNAc residue points into the C pocket and forms van der Waals and hydrogen bond interactions with the MHC class I. As predicted, GalNAc, a modified peptide carrying an addi ...[more]

PMID: 14657390

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