Linked Life Data

9151979

Source:http://linkedlifedata.com/resource/pubmed/id/9151979

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1997-7-3
pubmed:abstractText
Four peptidyl inhibitors of the small-conductance Ca2+-activated K+ channels (SK(Ca)) have been isolated from the venom of the Chinese scorpion Buthus martensi. These peptides were identified by screening C18 HPLC fractions of the crude venom by means of mass analysis by matrix-assisted-laser-desorption/ionization time-of-flight mass spectrometry, and toxicological tests in mice. Edman degradation analysis of the purified peptides showed sequences of 28-31 amino acids including 6 cysteine residues. Three of the sequences were similar to the P01 peptides from Androctonus scorpions, showing 76% sequence similarity for the most closely related, named BmP01, and 46% for the other two, named BmP02 and BmP03. Like the P01 peptides, these molecules showed a low toxic activity in mice after intracerebroventricular injection, and competed (K0.5 > 1 microM) with iodinated apamin for binding to its receptor site from rat brain, which has been proved to be the SK(Ca) channels. The fourth toxin was structurally related to the P05/leiurotoxin I toxin family, with 90% similarity, and was named BmP05. This toxin exhibited a high toxic activity with lethal effects in mice. Due to its small representation in the venom [less than 0.01% (by mass)], its biological properties have been assessed on the synthetic analogue of BmP05, which was assembled on a solid phase by means of Fmoc methodology. The synthetic peptide was physicochemically identical to the natural peptide, as shown by comparison of their molecular masses and amino acid compositions, and by their coelution after coinjection on capillary electrophoresis. These results confirmed the primary structure of BmP05 including an amidated C-terminus. Similarly to natural BmP05, synthetic BmP05 produced toxic and lethal effects after intracerebroventricular injection in mice (LD50 = 37 ng), and was able to compete with iodinated apamin for binding to its receptor in rat brain (K0.5 = 20 pM).
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0014-2956
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
245
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
457-64
pubmed:dateRevised
2007-7-23
pubmed:meshHeading
pubmed-meshheading:9151979-Amino Acid Sequence, pubmed-meshheading:9151979-Animals, pubmed-meshheading:9151979-Apamin, pubmed-meshheading:9151979-Chromatography, High Pressure Liquid, pubmed-meshheading:9151979-Chromatography, Ion Exchange, pubmed-meshheading:9151979-Mice, pubmed-meshheading:9151979-Molecular Sequence Data, pubmed-meshheading:9151979-Molecular Weight, pubmed-meshheading:9151979-Potassium Channels, pubmed-meshheading:9151979-Potassium Channels, Calcium-Activated, pubmed-meshheading:9151979-Rats, pubmed-meshheading:9151979-Scorpion Venoms, pubmed-meshheading:9151979-Small-Conductance Calcium-Activated Potassium Channels, pubmed-meshheading:9151979-Spectrometry, Mass, Matrix-Assisted Laser..., pubmed-meshheading:9151979-Structure-Activity Relationship, pubmed-meshheading:9151979-Synaptosomes
pubmed:year
1997
pubmed:articleTitle
Characterization of four toxins from Buthus martensi scorpion venom, which act on apamin-sensitive Ca2+-activated K+ channels.
pubmed:affiliation
Suntory Institute for Bioorganic Research, Wakayamadai, Osaka, Japan.
pubmed:publicationType
Journal Article