Observations on the calcium dependence and reversibility of cobalamin transport across the outer membrane of Escherichia coli.

@article{Cadieux2007ObservationsOT,
  title={Observations on the calcium dependence and reversibility of cobalamin transport across the outer membrane of Escherichia coli.},
  author={Nathalie Cadieux and Nazir Barekzi and Clive Bradbeer},
  journal={The Journal of biological chemistry},
  year={2007},
  volume={282 48},
  pages={34921-8}
}
The calcium dependence of cobalamin (Cbl) binding to the BtuB protein of Escherichia coli and the reversibility of its function in the transport of Cbl across the outer membrane have been examined. The results show that the two calcium-binding sites in BtuB that were identified previously by others are responsible for the calcium dependence of high affinity Cbl binding. The affinity of the pure BtuB protein for Cbl was approximately 1000-fold higher in the presence of saturating levels of… CONTINUE READING