2H9X

NMR structure for the CgNa toxin from the sea anemone Condylactis gigantea

Summary for 2H9X

• Entry DOI: 10.2210/pdb2h9x/pdb
• NMR Information: BMRB: 7166
• Descriptor: Toxin CgNa (1 entity in total)
• Functional Keywords: beta sheet, toxin
• Biological source: Condylactis gigantea (giant Caribbean anemone)
• Cellular location: Secreted: P0C280
• Total number of polymer chains: 1
• Total formula weight: 5056.55

Authors

Lopez-Mendez, B.,Perez-Castells, J.,Gimenez-Gallego, G.,Jimenez-Barbero, J. (deposition date: 2006-06-12, release date: 2007-06-05, Last modification date: 2022-03-09)

Primary citation

Salceda, E.,Perez-Castells, J.,Lopez-Mendez, B.,Garateix, A.,Salazar, H.,Lopez, O.,Aneiros, A.,Standker, L.,Beress, L.,Forssmann, W.G.,Soto, E.,Jimenez-Barbero, J.,Gimenez-Gallego, G.
CgNa, a type I toxin from the giant Caribbean sea anemone Condylactis gigantea shows structural similarities to both type I and II toxins, as well as distinctive structural and functional properties(1).
Biochem.J., 406:67-76, 2007

PubMed Abstract: CgNa (Condylactis gigantea neurotoxin) is a 47-amino-acid- residue toxin from the giant Caribbean sea anemone Condylactis gigantea. The structure of CgNa, which was solved by 1H-NMR spectroscopy, is somewhat atypical and displays significant homology with both type I and II anemone toxins. CgNa also displays a considerable number of exceptions to the canonical structural elements that are thought to be essential for the activity of this group of toxins. Furthermore, unique residues in CgNa define a characteristic structure with strong negatively charged surface patches. These patches disrupt a surface-exposed cluster of hydrophobic residues present in all anemone-derived toxins described to date. A thorough characterization by patch-clamp analysis using rat DRG (dorsal root ganglion) neurons indicated that CgNa preferentially binds to TTX-S (tetrodotoxin-sensitive) voltage-gated sodium channels in the resting state. This association increased the inactivation time constant and the rate of recovery from inactivation, inducing a significant shift in the steady state of inactivation curve to the left. The specific structural features of CgNa may explain its weaker inhibitory capacity when compared with the other type I and II anemone toxins.

PubMed: 17506725
DOI: 10.1042/BJ20070130

Experimental method

SOLUTION NMR