Nucleic Acids Research, 1980, Vol. 8, No. 16 3721-3728
© 1980
MOLECULAR BIOLOGY |
Site-specific DNA-affinity chromatography of the lac repressor
Department of Cellular, Viral and Molecular Biology, College of Medicine, University of Utah Salt Lake City, UT 84132, USA
Received April 24, 1980. To test the feasibility of site-specific DNA-affinity chromatography E. coli lac repressor was bound to an operator-containing DNA column, and in parallel to a non-operator DNA column. Salt gradient elution show: 1) elutlon from non-operator DNA was near 250mM KCl or NaCl; interpretation of this result suggests the usefulness of the procedure for studying salt-dependence of DNA-protein affinities; 2) elution frm operator-containing DNA was delayed (average elution=1000mM salt), demonstrating a feasibility of site-specific DNA-affinity chromatography, if one provides a sufficiently favorable ratio of specific to non-specific DNA binding sites; 3) repressor eluted fr operator-containing DNA over a very broad salt range, which may represent chromatography-generated repressor heterogeneity.