Thermodynamic parameters of AraR-DNA interaction reactions.

a<p>Dissociation constant (<i>K</i>_d) of binding of AraR and AraR mutants (Y5F, E30A) to a wild-type <i>araABDLMNPQ-abfA</i> promoter (WT) and mutants (OR_A1 T₆→G, T₁₆→G, A₁→C, G₅→T) calculated by densitometric quantification of the bands corresponding to free DNA and protein–DNA complex by EMSA (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0111802#s2" target="_blank">Materials and Methods</a>). The values represent the average and standard deviation of at least three (three to seven) independent assays, with an intrinsic error <31%.</p>b<p><i>p-value</i> (Mann Whitney U test) for each pairwise comparison, mutant DNA fragment <i>vs</i> wild-type DNA fragment. Mutated operators that did not show statistical significant variation (<i>p</i><0.05) when compared to the wild-type operator are highlighted in bold.</p>c<p>Gibbs free energy is calculated from the equilibrium association constant <i>K</i>_ass (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0111802#s2" target="_blank">Materials and Methods</a>).</p>d<p>Variation of Gibbs free energy = [Δ<i>G</i>°mutant−Δ<i>G</i>°wild-type]. ND – not determined.</p><p>Thermodynamic parameters of AraR-DNA interaction reactions.