Several new crystal structures of the 70S ribosome in complex with EFG and non-hydrolyzable GTP analogs have revealed how the ribosome directionally translocates mRNA and the tRNAs through the A, P, and E sites and how specific features of EFG and ribosomal RNA act as pawls to enforce this ratcheting mechanism. The new structures were…
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SIBYLS scientists have recently published and made available tools for generating [SAXS structural comparison maps](/saxs_similarity “SAXS structural comparison maps”). Details of the methods have been published in Nature Methods. >Biological macromolecular functions require distinct conformational states that are challenging to examine comprehensively. Current methods to quantify conformational similarities and distinguish different assembly states are underdeveloped.…
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Rob and John have a new review on SAXS and its application to systems biology published in the Annual Review of Biophysics. See if you can spot the musical theme. >Small-angle X-ray scattering (SAXS) is a robust technique for the comprehensive structural characterizations of biological macromolecular complexes in solution. Here, we present a coherent synthesis…
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Rob Rambo and John Tainer describe new SAS metrics in a paper titled “Accurate assessment of mass, models and resolution by small-angle scattering.” The paper has been published in the journal Nature. > “In SAS imaging, beams of X-rays or neutrons sent through a sample produce tiny collisions between the X-rays or neutrons and nano-…
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A manuscript highlighting the technical capabilities of the SIBYLS beamline has been published in the Journal of Applied Crystallography: > The SIBYLS beamline (12.3.1) of the Advanced Light Source at Lawrence Berkeley National Laboratory, supported by the US Department of Energy and the National Institutes of Health, is optimized for both small-angle X-ray scattering (SAXS)…
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A recent IDAT [publication](http://dx.doi.org/10.1107/S0909049512035571) from James, Chris, and Ken investigating the source of the point spread function in detectors using CCDs coupled fiber optic tapers. >The point-spread function (PSF) of a fiber-optic taper-coupled CCD area detector was measured over five decades of intensity using a 20 µm X-ray beam and 2000-fold averaging. The “tails” of…
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We bring to your attention a nice review published recently in the European Biophysics Journal describing the theoretical and practical considerations when using SAXS to characterize macromolecular flexibility. >The dynamics of macromolecular conformations are critical to the action of cellular networks. Solution X-ray scattering studies, in combination with macromolecular X-ray crystallography (MX) and nuclear magnetic…
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SAXS was used to characterize the structural effects of phosphorylation events that modulate the ability of retinoblastoma protein to associate with E2F and other proteins. This work has been published in Genes & Development in the May 8th Advanced Online Articles section. >Cyclin-dependent kinase (Cdk) phosphorylation of the Retinoblastoma protein (Rb) drives cell proliferation through…
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