Linked Life Data

9688256

Source:http://linkedlifedata.com/resource/pubmed/id/9688256

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1998-8-13
pubmed:databankReference
pubmed:abstractText
Potassium-channel-blocking scorpion toxins (alpha-K-toxins) have been shown to be valuable tools for the study of potassium channels. Here we report two toxins, cobatoxin 1 and 2, of 32 amino acids, containing three disulphide bridges, that were isolated from the venom of the Mexican scorpion Centruroides noxius. Their primary sequences show less than 40% identity to other alpha-K-toxins. It is therefore proposed that they belong to subfamily 9. The cDNA of cobatoxin 1 encodes a putative signal peptide, a putative short propeptide, the mature peptide and two amino acids that are processed to leave cobatoxin 1 amidated at the C-terminus. In rat brain synaptosomal membranes cobatoxin 1 and cobatoxin 2 bind to a common binding site of alpha-K-toxins with Ki values of 109 pM and 87 pM, respectively. Moreover, they block the Shaker and Kv1.1 K+ channels with moderate affinities, with Kd values of around 0.7 microM and 4.1 microM (Shaker) and 0.5 microM and 1.0 microM (Kv1.1), respectively. A three-dimensional model of cobatoxin 1 was generated and used to interpret the obtained functional data on a structural basis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0014-2956
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
254
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
468-79
pubmed:dateRevised
2007-7-23
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Cobatoxins 1 and 2 from Centruroides noxius Hoffmann constitute a subfamily of potassium-channel-blocking scorpion toxins.
pubmed:affiliation
Department of Molecular Recognition and Structural Biology, Institute of Biotechnology, Cuernavaca, Mexico.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't