Isolation and identification of a sodium channel-inhibiting protein from eggs of black widow spiders

Int J Biol Macromol. 2014 Apr:65:115-20. doi: 10.1016/j.ijbiomac.2014.01.004. Epub 2014 Jan 9.

Abstract

The eggs of black widow spider (L. tredecimguttatus) have been demonstrated to be rich in biologically active components that exhibit great research value and application foreground. In the present study, a protein toxin, named Latroeggtoxin-II, was isolated from the eggs using the combination of gel filtration, ion exchange chromatography and reversed-phase high performance liquid chromatography. Electrospray mass spectrometric analysis indicated that the molecular weight of the protein was 28.69 kDa, and Edman degradation revealed that its N-terminal sequence was ESIQT STYVP NTPNQ KFDYE VGKDY-. After being abdominally injected into mice and P. americana, the protein could make the animals especially P. americana display a series of poisoning symptoms. Electrophysiological experiments demonstrated that the protein could selectively inhibit tetrodotoxin-resistant Na(+) channel currents in rat dorsal root ganglion neurons, without significant effect on the tetrodotoxin-sensitive Na(+) channel currents. Using multiple proteomic strategies, the purified protein was shown to have only a few similarities to the existing proteins in the databases, suggesting that it was a novel protein isolated from the eggs of black widow spiders.

Keywords: Black widow spider; Characterization; Egg; Isolation; Protein; Toxin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Arthropod Proteins / analysis
  • Arthropod Proteins / chemistry
  • Arthropod Proteins / isolation & purification*
  • Arthropod Proteins / toxicity*
  • Black Widow Spider / chemistry*
  • Mice
  • Molecular Sequence Data
  • Molecular Weight
  • Ovum / chemistry*
  • Sodium Channel Blockers / analysis
  • Sodium Channel Blockers / chemistry
  • Sodium Channel Blockers / isolation & purification*
  • Sodium Channel Blockers / toxicity*
  • Sodium Channels / metabolism*

Substances

  • Arthropod Proteins
  • Sodium Channel Blockers
  • Sodium Channels