Purification, characterization of two peptides from Buthus martensi Karch
| Autor: | X. Xiao, Z.‐Y. Cao, D.‐Q. Yu, Pan Yp, Wang Xl, X.‐M. Liu, W.‐Q. Shen, X.‐T. Liang |
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| Rok vydání: | 2003 |
| Předmět: |
Male
Stereochemistry Buthus martensi Molecular Sequence Data Scorpion Venoms Peptide Venom Biochemistry Membrane Potentials Turn (biochemistry) Scorpions Mice Structure-Activity Relationship Endocrinology Animals Amino Acid Sequence Rats Wistar Peptide sequence chemistry.chemical_classification Chromatography Molecular mass Edman degradation Chemistry Circular Dichroism Sodium Sequence identity Rats Electrophysiology Molecular Weight Potassium Peptides |
| Zdroj: | The journal of peptide research : official journal of the American Peptide Society. 62(6) |
| ISSN: | 1397-002X |
| Popis: | A new peptide named Martentoxin I and an analogue Martentoxin were purified and characterized from the venom of Buthus martensi Karch. Martentoxin I consisted of 36 amino acid residues with molecular mass as 3908.0 Da determined by matrix-assisted laser desorption ionization time-of-flight-MS. The amino acid sequence was determined as GLIDVKCFASSECWTACKKVTGSGQGKCQNNQCRCY by Edman degradation. Martentoxin consisted of 37 amino acid residues with a molecular mass as 4055.3 Da and it showed highly sequence identity to Martentoxin I as FGLIDVKCFASSECWTACKKVTGSGQGKCQNNQCRCY. Estimation from circular dichroism spectra indicated Martentoxin I owned 18.0% alpha-helix, 53.0% beta-sheet structure and 3.9% turn while Martentoxin contained 13.3% alpha-helix, 64.3% beta-sheet structure and 1.1% turn. The toxicity assay showed both peptides had no toxic effects on mice up to the dose of 10 mg/kg. Electrophysiological studies showed that Martentoxin I and Martentoxin at the concentration of 1 microm significantly inhibited voltage-dependent Na+ current (INa) and voltage-dependent delayed rectifier K+ current (IK) but had no effects on transient K+ current (IA). Both interactions with Na+ and K+ channels were irreversible. |
| Databáze: | OpenAIRE |
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