Structure-function relationship of bifunctional scorpion toxin BmBKTx1.

  title={Structure-function relationship of bifunctional scorpion toxin BmBKTx1.},
  author={Suming Wang and Lijun Huang and Dieter Wicher and Cheng-wu Chi and Chenqi Xu},
  journal={Acta biochimica et biophysica Sinica},
  volume={40 11},
As the first identified scorpion toxin active on both big conductance Ca2+-activated K+ channels (BK) and small conductance Ca2+-activated K+ channels (SK), BmBKTx1 has been proposed to have two separate functional faces for two targets. To investigate this hypothesis, two double mutants, K21A-Y30A and R9A-K11A, together with wild-type toxin were expressed in Escherichia coli. The recombinant toxins were tested on cockroach BK and rat SK2 channel for functional assay. Mutant K21A-Y30A had a… 

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