Identification and characterization of functional subunits of Clostridium botulinum type A progenitor toxin involved in binding to intestinal microvilli and erythrocytes

FEBS Lett. 2000 Feb 11;467(2-3):179-83. doi: 10.1016/s0014-5793(00)01147-9.


Clostridium botulinum type A hemagglutinin-positive progenitor toxin consists of three distinct components: neurotoxin (NTX), hemagglutinin (HA), and non-toxic non-HA (NTNH). The HA consists of four subcomponents designated HA1, 2, 3a and 3b. By employing purified toxin and GST-fusion proteins of each HA subcomponent, we found that the HA-positive progenitor toxin, GST-HA1 and GST-HA3b bind to human erythrocytes and microvilli of guinea pig upper small intestinal sections. The HA-positive progenitor toxin and GST-HA1 bind via galactose moieties, GST-HA3b binds via sialic acid moieties. GST-2 and GST-3a showed no detectable binding.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / metabolism
  • Botulinum Toxins*
  • Botulinum Toxins, Type A / chemistry*
  • Botulinum Toxins, Type A / metabolism
  • Clostridium botulinum*
  • Erythrocytes / metabolism
  • Galactose / metabolism
  • Guinea Pigs
  • Hemagglutinins / chemistry*
  • Hemagglutinins / genetics
  • Hemagglutinins / metabolism
  • Intestine, Small / metabolism
  • Microvilli / metabolism
  • N-Acetylneuraminic Acid / metabolism
  • Recombinant Fusion Proteins / metabolism


  • Bacterial Proteins
  • Hemagglutinins
  • NTNH protein, Clostridium botulinum
  • Recombinant Fusion Proteins
  • Botulinum Toxins
  • Botulinum Toxins, Type A
  • N-Acetylneuraminic Acid
  • Galactose