1BGK

SEA ANEMONE TOXIN (BGK) WITH HIGH AFFINITY FOR VOLTAGE DEPENDENT POTASSIUM CHANNEL, NMR, 15 STRUCTURES

Summary for 1BGK

• Entry DOI: 10.2210/pdb1bgk/pdb
• Descriptor: BGK (1 entity in total)
• Functional Keywords: neurotoxin, potassium channel inhibitor
• Biological source: Bunodosoma granulifera
• Cellular location: Secreted: P29186
• Total number of polymer chains: 1
• Total formula weight: 4291.00

Authors

Dauplais, M.,Lecoq, A.,Song, J.,Cotton, J.,Jamin, N.,Gilquin, B.,Roumestand, C.,Vita, C.,Harvey, A.,Menez, A. (deposition date: 1996-05-08, release date: 1997-01-27, Last modification date: 2024-10-30)

Primary citation

Dauplais, M.,Lecoq, A.,Song, J.,Cotton, J.,Jamin, N.,Gilquin, B.,Roumestand, C.,Vita, C.,de Medeiros, C.L.,Rowan, E.G.,Harvey, A.L.,Menez, A.
On the convergent evolution of animal toxins. Conservation of a diad of functional residues in potassium channel-blocking toxins with unrelated structures.
J.Biol.Chem., 272:4302-4309, 1997

PubMed Abstract: BgK is a K+ channel-blocking toxin from the sea anemone Bunodosoma granulifera. It is a 37-residue protein that adopts a novel fold, as determined by NMR and modeling. An alanine-scanning-based analysis revealed the functional importance of five residues, which include a critical lysine and an aromatic residue separated by 6.6 +/- 1.0 A. The same diad is found in the three known homologous toxins from sea anemones. More strikingly, a similar functional diad is present in all K+ channel-blocking toxins from scorpions, although these toxins adopt a distinct scaffold. Moreover, the functional diads of potassium channel-blocking toxins from sea anemone and scorpions superimpose in the three-dimensional structures. Therefore, toxins that have unrelated structures but similar functions possess conserved key functional residues, organized in an identical topology, suggesting a convergent functional evolution for these small proteins.

PubMed: 9020148
DOI: 10.1074/jbc.272.7.4302

Experimental method

SOLUTION NMR