Figure 6.

ATP/ADP Quantification of L6, L7, and Their Mutants.

The percentage of L6, L7, and mutant proteins occupied by ATP and ADP was determined after NiA purification and concentration. L6^K271M and L7^K271M P-loop mutants were used as negative controls and confirmed that other copurifying proteins did not contribute to measurements of ATP and ADP. Nucleotide occupancy measurements of all proteins were done in triplicate and recorded with error bars representing 1 sd from the mean. One-way ANOVA, Tukey’s HSD post hoc test, and tests for normality and equal variances have been run and revealed the presence of four statistically different groups for ADP values (a to d). ATP occupancy was negligible in all samples and not significantly different from each other.