3eql

Crystal structure of the T. Thermophilus RNA polymerase holoenzyme in complex with antibiotic myxopyronin

spinqualitylabelsall models 3eql, resolution 2.70Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 3eql is a 12 chain structure with sequence from Thermus thermophilus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.7Å Ligands: MG, MXP, ZN Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function RPOA_THETH DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Structural studies of antibiotics not only provide a shortcut to medicine allowing for rational structure-based drug design, but may also capture snapshots of dynamic intermediates that become 'frozen' after inhibitor binding. Myxopyronin inhibits bacterial RNA polymerase (RNAP) by an unknown mechanism. Here we report the structure of dMyx--a desmethyl derivative of myxopyronin B--complexed with a Thermus thermophilus RNAP holoenzyme. The antibiotic binds to a pocket deep inside the RNAP clamp head domain, which interacts with the DNA template in the transcription bubble. Notably, binding of dMyx stabilizes refolding of the beta'-subunit switch-2 segment, resulting in a configuration that might indirectly compromise binding to, or directly clash with, the melted template DNA strand. Consistently, footprinting data show that the antibiotic binding does not prevent nucleation of the promoter DNA melting but instead blocks its propagation towards the active site. Myxopyronins are thus, to our knowledge, a first structurally characterized class of antibiotics that target formation of the pre-catalytic transcription initiation complex-the decisive step in gene expression control. Notably, mutations designed in switch-2 mimic the dMyx effects on promoter complexes in the absence of antibiotic. Overall, our results indicate a plausible mechanism of the dMyx action and a stepwise pathway of open complex formation in which core enzyme mediates the final stage of DNA melting near the transcription start site, and that switch-2 might act as a molecular checkpoint for DNA loading in response to regulatory signals or antibiotics. The universally conserved switch-2 may have the same role in all multisubunit RNAPs. Transcription inactivation through local refolding of the RNA polymerase structure.,Belogurov GA, Vassylyeva MN, Sevostyanova A, Appleman JR, Xiang AX, Lira R, Webber SE, Klyuyev S, Nudler E, Artsimovitch I, Vassylyev DG Nature. 2009 Jan 15;457(7227):332-5. Epub 2008 Oct 22. PMID:18946472 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also RNA polymerase 3D structures Sigma factor 3D structures

Proteopedia Page Contributors and Editors (what is this?)

OCA