Taking as an example a set of nitroxide polyradicals of known structure we have analysed the possibilities of determining the reciprocal arrangement of the spins of the nitroxide fragments from the form and the second moment of the EPR spectra of the radicals in solid magnetodilute solutions at T77 °K. It has been shown that the EPR spectra are sensitive to the distance between the spins if it does not exceed 17-18 Å. The method of paramagnetic labels has been used to evaluate the distances between the functional groups in lysozyme (histidine, lysines), myoglobin (histidines) and myosin (sulphydryl groups). The results for lysozyme and myoglobin are in satisfactory agreement with the X-ray structural models of the proteins.
|Number of pages||8|
|Journal||Biophysics (Russian Federation)|
|State||Published - 1 Dec 1972|