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Crystal structure of a superantigen bound to MHC class II displays zinc and peptide dependence.

ABSTRACT: The three-dimensional structure of a bacterial superantigen, Staphylococcus aureus enterotoxin H (SEH), bound to human major histocompatibility complex (MHC) class II (HLA-DR1) has been determined by X-ray crystallography to 2.6 A resolution (1HXY). The superantigen binds on top of HLA-DR1 in a completely different way from earlier co-crystallized superantigens from S.aureus. SEH interacts with high affinity through a zinc ion with the beta1 chain of HLA-DR1 and also with the peptide presented by HLA-DR1. The structure suggests that all superantigens interacting with MHC class II in a zinc-dependent manner present the superantigen in a common way. This suggests a new model for ternary complex formation with the T-cell receptor (TCR), in which a contact between the TCR and the MHC class II is unlikely.

SUBMITTER: Petersson K

PROVIDER: S-EPMC125526 | biostudies-literature | 2001 Jul

REPOSITORIES: biostudies-literature

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Crystal structure of a superantigen bound to MHC class II displays zinc and peptide dependence.

Petersson K K Håkansson M M Nilsson H H Forsberg G G Svensson L A LA Liljas A A Walse B B

The EMBO journal 20010701 13

The three-dimensional structure of a bacterial superantigen, Staphylococcus aureus enterotoxin H (SEH), bound to human major histocompatibility complex (MHC) class II (HLA-DR1) has been determined by X-ray crystallography to 2.6 A resolution (1HXY). The superantigen binds on top of HLA-DR1 in a completely different way from earlier co-crystallized superantigens from S.aureus. SEH interacts with high affinity through a zinc ion with the beta1 chain of HLA-DR1 and also with the peptide presented b ...[more]

PMID: 11432818

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