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Fluorescent analogues of BeKm-1 with high and specific activity against the hERG channel.

ABSTRACT: Peptidic toxins that target specifically mammalian channels and receptors can be found in the venom of animals. These toxins are rarely used directly as tools for biochemical experiments, and need to be modified via the attachment of chemical groups (e.g., radioactive or fluorescent moieties). Ideally, such modifications should maintain the toxin specificity and affinity for its target. With the goal of obtaining fluorescent derivatives of BeKm-1, a toxin from the scorpion species Buthus eupeus that selectively inhibits the voltage-gated potassium ion channel hERG, we produced four active analogues using a model of BeKm-1 docking to the outer mouth of the channel. In these BeKm-1 analogues, the natural peptide was linked to the fluorescent cyanine 5 (Cy5) probe via four different linkers at Arg1 or Arg/Lys27. All analogues retained their specificity towards the hERG channel in electrophysiological experiments but displayed a lesser affinity. These results validate our strategy for designing toxin analogues and demonstrate that different chemical groups can be attached to different residues of BeKm-1.

SUBMITTER: Vasseur L

PROVIDER: S-EPMC7285999 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Fluorescent analogues of BeKm-1 with high and specific activity against the hERG channel.

Vasseur Lucie L Chavanieu Alain A Combemale Stéphanie S Caumes Cécile C Béroud Rémy R De Waard Michel M Ducrot Pierre P Boutin Jean A JA Ferry Gilles G Cens Thierry T

Toxicon: X 20190223

Peptidic toxins that target specifically mammalian channels and receptors can be found in the venom of animals. These toxins are rarely used directly as tools for biochemical experiments, and need to be modified via the attachment of chemical groups (e.g., radioactive or fluorescent moieties). Ideally, such modifications should maintain the toxin specificity and affinity for its target. With the goal of obtaining fluorescent derivatives of BeKm-1, a toxin from the scorpion species <i>Buthus eupe ...[more]

PMID: 32550567

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Fluorescent analogues of BeKm-1 with high and specific activity against the hERG channel.

Publications

Fluorescent analogues of BeKm-1 with high and specific activity against the hERG channel.

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