Mechanistic Insights Revealed by the Crystal Structure of a Histidine Kinase with Signal Transducer and Sensor Domains
Figure 5
Proline and threonine are essential for VicK phosphatase activity.
(A) VicR dephosphorylation examined in PMS. Phosphorylated VicR was treated with the same amount of VicK wt or its mutants as shown in the bottom gel. Native and phosphorylated VicR were separated in PMS as labeled on the right of the top two gels, where in one series of reactions additional 5 mM ATP was used (the top 1 gel). (B) VicK phosphatase activity analyzed by HPLC. AcP-treated VicR was incubated with VicK in the reaction buffer with 5 mM ATP (right) and without ATP (left). VicK phosphatase activity was analyzed by the phosphorylation state of VicR on HPLC.