Structure-function relationship of bifunctional scorpion toxin BmBKTx1.

@article{Wang2008StructurefunctionRO,
  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},
  year={2008},
  volume={40 11},
  pages={
          955-63
        }
}
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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Characterization of Kbot21 Reveals Novel Side Chain Interactions of Scorpion Toxins Inhibiting Voltage-Gated Potassium Channels
TLDR
A new short polypeptide called Kbot21 has been purified to homogeneity from the venom of Buthus occitanus tunetanus scorpion, structurally related to BmBKTx1 from the Venom of the Asian scorpion Buthus martensii Karsch.

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