Fig 1. PAP2 proteins purification and effect of the pH on their UppP activity.
The N-terminal His-tagged PAP2 proteins were purified on Ni2+-NTA-agarose beads as detailed in Materials and Methods, and 10 μL aliquots of the elution fractions were analyzed by SDS-PAGE. The proteins were revealed either (A) by Coomassie blue staining or (B) by Western blotting using anti·His tag antibody conjugated to the horseradish peroxidase (C) UppP phosphatase activity present in the purified solutions was determined at different pH (from pH 3 to pH 11). LpxE (black), HP0350 (blue), HP0851 (HupA; brown) and LpxF (red) The values are also reported in Table 2. The observed molecular weight of recombinant proteins are consistent with their calculated molecular weight: LpxE (21,2 kDa), HP0350 (24,5 kDa), HupA (25,8 kDa) and LpxF (24,6 kDa).