Inhibition of LexA binding to the operator by operator mutants

Copyright information:Taken from "Binding of the LexA protein to the SOS operator"Nucleic Acids Research 2005;33(19):6287-6295.Published online 3 Nov 2005PMCID:PMC1277809.© The Author 2005. Published by Oxford University Press. All rights reserved Mobility shift assays were conducted as described in Materials and Methods with purified LexA, radiolabeled promoter DNA (5.0 nM) and a 100-fold molar excess of competitor operator mutant. Base changes are indicated by position from the 5′ end of the 14 bp operator, and the base substitution relative to the operator sequence. Lower and upper bands correspond to unbound and LexA-bound promoter DNA, respectively. Lanes corresponding to no addition of competitor DNA and non-specific DNA [poly(dI–dC)] are indicated. LexA concentrations given are for the total amount of LexA.