Recombinant Peptides Ce1 and Ce4 from the Venom of Scorpion Centruroides elegans and Their Interactions with Hybrid Channels KcsA-Kv1.x (x = 1, 3, 6)

A technique has been developed for obtaining recombinant functionally active peptides Ce1 and Ce4 from the venom of the scorpion Centruroides elegans in the Escherichia coli expression system. The yields of peptides Ce1 and Ce4 were 6.5 and 12 mg per liter of culture, respectively. The properties of the obtained peptides were studied using bioengineered systems based on hybrid channels KcsA-K v 1.x (x = 1, 3, 6) containing blocker binding sites of the corresponding eukaryotic potassium channels of K v 1-family. It has been shown that recombinant Ce1 and Ce4 do not exhibit affinity to the binding sites of K v 1.1 and K v 1.6 channels up to micromolar concentrations and, like natural peptides, selectively interact with the binding site of the K v 1.3 channel: the apparent dissociation constants of KcsA-K v 1.3 complexes with recombinant Ce1 and Ce4 are 50 ± 10 and 200 ± 30 nM (mean ± SEM), respectively.