4w90

Crystal structure of Bacillus subtilis cyclic-di-AMP riboswitch ydaOCrystal structure of Bacillus subtilis cyclic-di-AMP riboswitch ydaO

Structural highlights 4w90 is a 2 chain structure. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: , NonStd Res: Resources: FirstGlance, OCA, RCSB, PDBsum Publication Abstract from PubMed Cyclic diadenosine monophosphate (c-di-AMP) is a second messenger that is essential for growth and homeostasis in bacteria. A recently discovered c-di-AMP-responsive riboswitch controls the expression of genes in a variety of bacteria, including important pathogens. To elucidate the molecular basis for specific binding of c-di-AMP by a gene-regulatory mRNA domain, we have determined the co-crystal structure of this riboswitch. Unexpectedly, the structure reveals an internally pseudo-symmetric RNA in which two similar three-helix-junction elements associate head-to-tail, creating a trough that cradles two c-di-AMP molecules making quasi-equivalent contacts with the riboswitch. The riboswitch selectively binds c-di-AMP and discriminates exquisitely against other cyclic dinucleotides, such as c-di-GMP and cyclic-AMP-GMP, via interactions with both the backbone and bases of its cognate second messenger. Small-angle X-ray scattering experiments indicate that global folding of the riboswitch is induced by the two bound cyclic dinucleotides, which bridge the two symmetric three-helix domains. This structural reorganization likely couples c-di-AMP binding to gene expression. Crystal structure of a c-di-AMP riboswitch reveals an internally pseudo-dimeric RNA.,Jones CP, Ferre-D'Amare AR EMBO J. 2014 Sep 30. pii: e201489209. PMID:25271255 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

spinqualitylabelsall models 4w90, resolution 3.12Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image