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Probing Protein Secondary Structure using EPR: Investigating a Dynamic Region of Visual Arrestin. Appl Magn Reson 2012 Oct;43(3):405-419



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One key application of site-directed spin labeling (SDSL) electron paramagnetic resonance (EPR) spectroscopy is the determination of sequence-specific secondary structure in proteins. Regular secondary structure leads to a periodic variation in both side chain motion and solvent accessibility, two properties easily monitored by EPR techniques. Specifically, saturation recovery (SR) EPR spectroscopy has proven to be useful for making accessibility measurements for multiple protein structure populations by determining individual accessibilities and is therefore well suited to study the structure of proteins exhibiting multiple conformations in equilibrium. Here we employ both continuous wave and SR EPR spectroscopy in combination to examine the secondary structure of a short sequence showing conformational heterogeneity in visual rod arrestin. The EPR data presented here clearly distinguish between the unstructured loop and the helical structure formed in the crystallographic tetramer of visual arrestin and show that this region is unstructured in solution.

Author List

Francis DJ, Hubbell WL, Klug CS


Candice S. Klug PhD Professor in the Biophysics department at Medical College of Wisconsin

jenkins-FCD Prod-468 69a93cef3257f26b866d455c1d2b2d0f28382f14