Role of protons in the pump cycle of KdpFABC investigated by time-resolved kinetic experiments.

@article{Damnjanovi2014RoleOP,
  title={Role of protons in the pump cycle of KdpFABC investigated by time-resolved kinetic experiments.},
  author={Bojana Damnjanovi{\'c} and Hans-J{\"u}rgen Apell},
  journal={Biochemistry},
  year={2014},
  volume={53 19},
  pages={
          3218-28
        }
}
The time-resolved kinetics of the KdpFABC complex solubilized in Aminoxide WS-35 was investigated by ATP concentration jump experiments. ATP was photoreleased from its inactive precursor, caged ATP, and charge movements in the membrane domain of the KdpFABC were detected by the electrochromic dye RH421. At low ATP concentrations, the ATP binding step became rate-limiting with an apparent, pH-independent ATP binding affinity of ~70 μM. At saturating ATP concentrations, the rate-limiting step is… Expand
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