Tryptophan 121 of Subunit II Is the Electron Entry Site to Cytochrome-c Oxidase in Paracoccus denitrificans

@article{Witt1998Tryptophan1O,
  title={Tryptophan 121 of Subunit II Is the Electron Entry Site to Cytochrome-c Oxidase in Paracoccus denitrificans},
  author={Heike Witt and Francesco Malatesta and Flavia Nicoletti and Maurizio Brunori and Bernd Ludwig},
  journal={The Journal of Biological Chemistry},
  year={1998},
  volume={273},
  pages={5132 - 5136}
}
To investigate the contribution of hydrophobic residues to the molecular recognition of cytochrome c with cytochrome oxidase, we mutated several hydrophobic amino acids exposed on subunit II of the Paracoccus denitrificans oxidase.K M and k cat values and the bimolecular rate constant were determined under steady- or presteady-state conditions, respectively. We present evidence that Trp-121 which is surrounded by a hydrophobic patch is the electron entry site to oxidase. Mutations in this… Expand
Mutations in the docking site for cytochrome c on the Paracoccus heme aa3 oxidase. Electron entry and kinetic phases of the reaction.
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