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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
30
|
| pubmed:dateCreated |
1991-8-27
|
| pubmed:abstractText |
The binding of the competitive antagonist alpha-bungarotoxin (alpha-Btx) and the noncompetitive inhibitor phencyclidine (PCP) to a synthetic peptide comprising residues 172-227 of the alpha-subunit of the Torpedo acetylcholine receptor has been characterized. 125I-alpha-Btx bound to the 172-227 peptide in a solid-phase assay and was competed by alpha-Btx (IC50 = 5.0 x 10(-8) M), d-tubocurarine (IC50 = 5.9 X 10(-5)M), and NaCl (IC50 = 7.9 x 10(-2)M). In the presence of 0.02% sodium dodecyl sulfate, 125I-alpha-Btx bound to the 56-residue peptide with a KD of 3.5 nM, as determined by equilibrium saturation binding studies. Because alpha-Btx binds to a peptide comprising residues 173-204 with the same affinity and does not bind to a peptide comprising residues 205-227, the competitive antagonist and hence agonist binding site lies between residues 173 and 204. After photoaffinity labeling, [3H]PCP was bound to the 172-227 peptide. [3H]PCP binding was inhibited by chlorpromazine (IC50 = 6.3 x 10(-5)M), tetracaine (IC50 = 4.2 x 10(-6)M), and dibucaine (IC50 = 2.7 x 10(-4)M). Equilibrium saturation binding studies in the presence of 0.02% sodium dodecyl sulfate showed that [3H]PCP bound at two sites, a major site of high affinity with an apparent KD of 0.4 microM and a minor low-affinity site with an apparent KD of 4.6 microM. High -affinity binding occurred at a single site on peptide 205-227 (KD = 0.27 microM) and was competed by chlorpromazine but not by alpha-Btx.(ABSTRACT TRUNCATED AT 250 WORDS)
|
| pubmed:grant | |
| 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 |
30
|
| pubmed:volume |
30
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
7484-91
|
| pubmed:dateRevised |
2007-11-14
|
| pubmed:meshHeading |
pubmed-meshheading:1854749-Amino Acid Sequence,
pubmed-meshheading:1854749-Animals,
pubmed-meshheading:1854749-Binding, Competitive,
pubmed-meshheading:1854749-Binding Sites,
pubmed-meshheading:1854749-Bungarotoxins,
pubmed-meshheading:1854749-Molecular Sequence Data,
pubmed-meshheading:1854749-Peptide Fragments,
pubmed-meshheading:1854749-Phencyclidine,
pubmed-meshheading:1854749-Receptors, Nicotinic,
pubmed-meshheading:1854749-Torpedo
|
| pubmed:year |
1991
|
| pubmed:articleTitle |
Binding sites for alpha-bungarotoxin and the noncompetitive inhibitor phencyclidine on a synthetic peptide comprising residues 172-227 of the alpha-subunit of the nicotinic acetylcholine receptor.
|
| pubmed:affiliation |
Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06510.
|
| pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
|