help button home button Biophys. J.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS

Biophysical Journal 3: 275-297 (1963)
© 1963 the Biophysical Society

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Blois, M. S.
Right arrow Articles by Taskovich, L. T.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Blois, M. S., Jr.
Right arrow Articles by Taskovich, L. T.

On the Electron Spin Resonances in DNA

M. S. Blois, Jr., J. E. Maling and L. T. Taskovich

ABSTRACT

Iron impurities are shown to account for characteristic electron spin resonances observed in samples of DNA. Comparative e.s.r. measurements on lyophilized samples were done in conjunction with static susceptibility measurements, trace analyses, and molecular degradation experiments to establish this correlation. It has not been possible to extract this iron by treatment with a chelating agent. Such resonances were in part accounted for by ferromagnetic iron contamination during extraction and handling. By modifying the method of Kay, Simmons, and Dounce to eliminate or minimize metal contamination—ionic and ferromagnetic—from sources both internal and external to the tissues used, it was possible to prepare iron-free (< 0.0004 per cent Fe), e.s.r.-free (< 0.001 per cent Fe) DNA. The samples showed 20 per cent protein (determined by the indole method), had a molecular weight 4 x 106 and were undenatured according to the density gradient experiment.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1963 by the Biophysical Society.