Snake venomics of monocled cobra (Naja kaouthia) and investigation of human IgG response against venom toxins

Toxicon. 2015 Jun 1;99:23-35. doi: 10.1016/j.toxicon.2015.03.001. Epub 2015 Mar 11.

Abstract

The venom proteome of the monocled cobra, Naja kaouthia, from Thailand, was characterized by RP-HPLC, SDS-PAGE, and MALDI-TOF-TOF analyses, yielding 38 different proteins that were either identified or assigned to families. Estimation of relative protein abundances revealed that venom is dominated by three-finger toxins (77.5%; including 24.3% cytotoxins and 53.2% neurotoxins) and phospholipases A2 (13.5%). It also contains lower proportions of components belonging to nerve growth factor, ohanin/vespryn, cysteine-rich secretory protein, C-type lectin/lectin-like, nucleotidase, phosphodiesterase, metalloproteinase, l-amino acid oxidase, cobra venom factor, and cytidyltransferase protein families. Small amounts of three nucleosides were also evidenced: adenosine, guanosine, and inosine. The most relevant lethal components, categorized by means of a 'toxicity score', were α-neurotoxins, followed by cytotoxins/cardiotoxins. IgGs isolated from a person who had repeatedly self-immunized with a variety of snake venoms were immunoprofiled by ELISA against all venom fractions. Stronger responses against larger toxins, but lower against the most critical α-neurotoxins were obtained. As expected, no neutralization potential against N. kaouthia venom was therefore detected. Combined, our results display a high level of venom complexity, unveil the most relevant toxins to be neutralized, and provide prospects of discovering human IgGs with toxin neutralizing abilities through use of phage display screening.

Keywords: Human IgG response; Immunity; Monocled cobra; Naja kaouthia; Snake venom: proteomics; Toxicity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antivenins / analysis*
  • Cobra Cardiotoxin Proteins / antagonists & inhibitors
  • Cobra Cardiotoxin Proteins / chemistry
  • Cobra Cardiotoxin Proteins / isolation & purification
  • Cobra Cardiotoxin Proteins / toxicity
  • Cobra Neurotoxin Proteins / antagonists & inhibitors
  • Cobra Neurotoxin Proteins / chemistry
  • Cobra Neurotoxin Proteins / isolation & purification
  • Cobra Neurotoxin Proteins / toxicity
  • Elapid Venoms / antagonists & inhibitors
  • Elapid Venoms / chemistry
  • Elapid Venoms / toxicity*
  • Elapidae / immunology
  • Elapidae / metabolism*
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Immunoglobulin G / analysis*
  • Immunoglobulin G / isolation & purification
  • Lethal Dose 50
  • Mice
  • Molecular Sequence Data
  • Peptide Fragments / antagonists & inhibitors
  • Peptide Fragments / chemistry
  • Peptide Fragments / isolation & purification
  • Peptide Fragments / toxicity
  • Peptide Mapping
  • Phospholipases A2 / chemistry
  • Phospholipases A2 / isolation & purification
  • Phospholipases A2 / toxicity
  • Proteomics
  • Reptilian Proteins / antagonists & inhibitors
  • Reptilian Proteins / chemistry
  • Reptilian Proteins / isolation & purification
  • Reptilian Proteins / toxicity*
  • Snake Bites / blood
  • Snake Bites / immunology*
  • Snake Bites / metabolism
  • Thailand

Substances

  • Antivenins
  • Cobra Cardiotoxin Proteins
  • Cobra Neurotoxin Proteins
  • Elapid Venoms
  • Immunoglobulin G
  • Naja kaouthia venom
  • Peptide Fragments
  • Reptilian Proteins
  • Phospholipases A2