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Structural basis of cooperative ligand binding by the glycine riboswitch.

ABSTRACT: The glycine riboswitch regulates gene expression through the cooperative recognition of its amino acid ligand by a tandem pair of aptamers. A 3.6 Å crystal structure of the tandem riboswitch from the glycine permease operon of Fusobacterium nucleatum reveals the glycine binding sites and an extensive network of interactions, largely mediated by asymmetric A-minor contacts, that serve to communicate ligand binding status between the aptamers. These interactions provide a structural basis for how the glycine riboswitch cooperatively regulates gene expression.

SUBMITTER: Butler EB

PROVIDER: S-EPMC3076126 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Structural basis of cooperative ligand binding by the glycine riboswitch.

Butler Ethan B EB Xiong Yong Y Wang Jimin J Strobel Scott A SA

Chemistry & biology 20110301 3

The glycine riboswitch regulates gene expression through the cooperative recognition of its amino acid ligand by a tandem pair of aptamers. A 3.6 Å crystal structure of the tandem riboswitch from the glycine permease operon of Fusobacterium nucleatum reveals the glycine binding sites and an extensive network of interactions, largely mediated by asymmetric A-minor contacts, that serve to communicate ligand binding status between the aptamers. These interactions provide a structural basis for how ...[more]

PMID: 21439473

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