1SIS

SPATIAL STRUCTURE OF INSECTOTOXIN I5A BUTHUS EUPEUS BY 1H NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY (RUSSIAN)

Summary for 1SIS

• Entry DOI: 10.2210/pdb1sis/pdb
• Descriptor: SCORPION INSECTOTOXIN I5A (1 entity in total)
• Functional Keywords: toxin
• Biological source: Mesobuthus eupeus (lesser Asian scorpion)
• Cellular location: Secreted: P15222
• Total number of polymer chains: 1
• Total formula weight: 3837.64

Authors

Arseniev, A.S.,Kondakov, V.I.,Lomize, A.L.,Maiorov, V.N.,Bystrov, V.F. (deposition date: 1993-11-11, release date: 1994-04-30, Last modification date: 2024-11-20)

Primary citation

Lomize, A.L.,Maiorov, V.N.,Arsen'ev, A.S.
Determination of the spatial structure of insectotoxin 15A from Buthus erpeus by (1)H-NMR spectroscopy data
Bioorg.Khim., 17:1613-1632, 1991

PubMed Abstract: The solution structure of insectotoxin 15A (35 residues) from scorpion Buthus eupeus was determined on the basis of 386 interproton distance restraints 12 hydrogen-bonding restraints and 113 dihedral angle restraints derived from 1H NMR experiments. A group of 20 structures was calculated with the distance geometry program DIANA followed by the restrained energy minimization with the program CHARMM. The atomic RMS distribution about the mean coordinate position is 0.64 +/- 0.11 A for the backbone atoms and 1.35 +/- 0.20 A for all atoms. The structure contains an alpha-helix (residues 10-20) and a three-stranded antiparallel beta-sheet (residues 2-5, 24-28 and 29-33). A pairing of the eight cysteine residues of insectotoxin 15A was established basing on NMR data. Three disulfide bridges (residues 2-19, 16-31 and 20-33) connect the alpha-helix with the beta-sheet, and the fourth one (5-26) joins beta-strands together. The spatial fold of secondary structure elements (the alpha-helix and the beta-sheet) of the insectotoxin 15A is very similar to those of the other short and long scorpion toxins in spite of a low (about 20%) sequence homology.

PubMed: 1815511

Experimental method

SOLUTION NMR