6BX9

Solution structure of conotoxin reg3b

Summary for 6BX9

• Entry DOI: 10.2210/pdb6bx9/pdb
• NMR Information: BMRB: 30385
• Descriptor: Conotoxin (1 entity in total)
• Functional Keywords: mini-m, multi-turn scaffold, toxin
• Biological source: Conus regius (Crown cone)
• Total number of polymer chains: 1
• Total formula weight: 1678.08

Authors

Mari, F.,Dovell, S. (deposition date: 2017-12-18, release date: 2018-01-24, Last modification date: 2024-10-30)

Primary citation

Franco, A.,Dovell, S.,Moller, C.,Grandal, M.,Clark, E.,Mari, F.
Structural plasticity of mini-M conotoxins - expression of all mini-M subtypes by Conus regius.
FEBS J., 285:887-902, 2018

PubMed Abstract: The mini-M conotoxins are peptidic scaffolds found in the venom of cones snails. These scaffolds are tightly folded structures held together by three disulfide bonds with a CC-C-C-CC arrangement (conotoxin framework III) and belong to the M Superfamily of conotoxins. Here, we describe mini-M conotoxins from the venom of Conus regius, a Western Atlantic worm-hunting cone snail species using transcriptomic and peptidomic analyses. These C. regius conotoxins belong to three different subtypes: M1, M2, and M3. The subtypes show little sequence homology, and their loop sizes (intercysteine amino acid chains) vary significantly. The mini-Ms isolated from dissected venom contains preferentially hydroxylated proline residues, thus augmenting the structural reach of this conotoxin class. Using 2D-NMR methods, we have determined the 3D structure of reg3b, an M2 subtype conotoxin, which shows a constrained multi-turn scaffold. The structural diversity found within mini-M conotoxin scaffolds of C. regius is indicative of structural hypervariability of the conotoxin M superfamily that is not seen in other superfamilies. These stable minimalistic scaffolds may be investigated for the development of engineered peptides for therapeutic applications.

PubMed: 29283511
DOI: 10.1111/febs.14372

Experimental method

SOLUTION NMR