Characterisation of a novel A-superfamily conotoxin

Journal Publication ResearchOnline@JCU
Wilson, David;Bansal, Paramjit S.;Carter, David A.;Vetter, Irina;Nicke, Annette;Dutertre, Sébastien;Daly, Norelle
Abstract

Conopeptides belonging to the A-superfamily from the venomous molluscs, Conus, are typically α-conotoxins. The α-conotoxins are of interest as therapeutic leads and pharmacological tools due to their selectivity and potency at nicotinic acetylcholine receptor (nAChR) subtypes. Structurally, the α-conotoxins have a consensus fold containing two conserved disulfide bonds that define the two-loop framework and brace a helical region. Here we report on a novel α-conotoxin Pl168, identified from the transcriptome of Conus planorbis, which has an unusual 4/8 loop framework. Unexpectedly, NMR determination of its three-dimensional structure reveals a new structural type of A-superfamily conotoxins with a different disulfide-stabilized fold, despite containing the conserved cysteine framework and disulfide connectivity of classical α-conotoxins. The peptide did not demonstrate activity on a range of nAChRs, or Ca2+ and Na+ channels suggesting that it might represent a new pharmacological class of conotoxins.

Journal

Biomedicines

Publication Name

N/A

Volume

8

ISBN/ISSN

2227-9059

Edition

N/A

Issue

5

Pages Count

10

Location

N/A

Publisher

MDPI

Publisher Url

N/A

Publisher Location

N/A

Publish Date

N/A

Url

N/A

Date

N/A

EISSN

N/A

DOI

10.3390/biomedicines8050128