You are not currently logged in.
Access JSTOR through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Determination of the Distance Between Two Spin Labels Attached to a Macromolecule
Mark D. Rabenstein and Yeon-Kyun Shin
Proceedings of the National Academy of Sciences of the United States of America
Vol. 92, No. 18 (Aug. 29, 1995), pp. 8239-8243
Published by: National Academy of Sciences
Stable URL: http://www.jstor.org/stable/2368033
Page Count: 5
You can always find the topics here!Topics: Spin labels, Spectral methods, Macromolecules, Product labeling, Electrons, Noise spectra, Impurities, Magnetism, Tensors, Biophysics
Were these topics helpful?See something inaccurate? Let us know!
Select the topics that are inaccurate.
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
An EPR "spectroscopic ruler" was developed using a series of α-helical polypeptides, each modified with two nitroxide spin labels. The EPR line broadening due to electron-electron dipolar interactions in the frozen state was determined using the Fourier deconvolution method. These dipolar spectra were then used to estimate the distances between the two nitroxides separated by 8-25 Å. Results agreed well with a simple α-helical model. The standard deviation from the model system was 0.9 Å in the range of 8-25 Å. This technique is applicable to complex systems such as membrane receptors and channels, which are difficult to access with high-resolution NMR or x-ray crystallography, and is expected to be particularly useful for systems for which optical methods are hampered by the presence of light-interfering membranes or chromophores.
Proceedings of the National Academy of Sciences of the United States of America © 1995 National Academy of Sciences