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Crystal structure of a fully glycosylated HIV-1 gp120 core reveals a stabilizing role for the glycan at Asn262.

ABSTRACT: The crystal structure of a fully glycosylated HIV-1 gp120 core in complex with CD4 receptor and Fab 17b at 4.5-Å resolution reveals 9 of the 15 N-linked glycans of core gp120 to be partially ordered. The glycan at position Asn262 had the most extensive and well-ordered electron density, and a GlcNAc(2)Man(7) was modeled. The GlcNAc stem of this glycan is largely buried in a cleft in gp120, suggesting a role in gp120 folding and stability. Its arms interact with the stems of neighboring glycans from the oligomannose patch, which is a major target for broadly neutralizing antibodies.

SUBMITTER: Kong L

PROVIDER: S-EPMC4409329 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Crystal structure of a fully glycosylated HIV-1 gp120 core reveals a stabilizing role for the glycan at Asn262.

Kong Leopold L Wilson Ian A IA Kwong Peter D PD

Proteins 20150122 3

The crystal structure of a fully glycosylated HIV-1 gp120 core in complex with CD4 receptor and Fab 17b at 4.5-Å resolution reveals 9 of the 15 N-linked glycans of core gp120 to be partially ordered. The glycan at position Asn262 had the most extensive and well-ordered electron density, and a GlcNAc(2)Man(7) was modeled. The GlcNAc stem of this glycan is largely buried in a cleft in gp120, suggesting a role in gp120 folding and stability. Its arms interact with the stems of neighboring glycans f ...[more]

PMID: 25546301

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