Linked Life Data

6269580

Source:http://linkedlifedata.com/resource/pubmed/id/6269580

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
14
pubmed:dateCreated
1981-12-21
pubmed:abstractText
Fluorescent and photoactivatable fluorescent derivatives of tetrodotoxin (TTX) have been synthesized. N-Methylanthraniloylglycine hydrazide, anthraniloyl hydrazide, and 2-azidoanthraniloylglycine hydrazide were coupled to the carbonyl at C6 of oxidized tetrodotoxin to form stable fluorescent hydrazones. The C6 ketone can be reductively aminated with either ammonium or methylammonium acetate to form 6-amino- or 6-(methylamino)tetrodotoxin, which can then be acylated by a variety of fluorescent reagents. The biological activity, competitive binding with [3H]tetrodotoxin for the receptor on rat axonal membranes, and equilibrium binding isotherms obtained by fluorescence enhancement or anisotropy indicate that the derivatives are only about 2-5 times less active then tetrodotoxin itself. The 2-azidoanthraniloylglycine hydrazone of oxidized tetrodotoxin, when activated by light, generates a reactive nitrene which is capable of covalent insertion into the toxin receptor. The product of the photolysis is a highly fluorescent tetrodotoxin derivative which is irreversibly linked to the receptor site. The excitation and emission spectra of the fluorescent tetrodotoxin derivatives vary with solvent polarity, and this sensitivity has been used to determine the immediate environmental characteristics of the toxin binding site of the sodium channel. It is concluded that the toxin binding site is highly polar. Emission and excitation spectra reveal that radiationless energy is transferred from tryptophan residues of the receptor to the anthraniloyl group of the TTX derivatives.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
7
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4107-18
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1981
pubmed:articleTitle
Fluorescent and photoactivatable fluorescent derivatives of tetrodotoxin to probe the sodium channel of excitable membranes.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't