Clostridium botulinum type A haemagglutinin-positive progenitor toxin (HA(+)-PTX) binds to oligosaccharides containing Gal beta1-4GlcNAc through one subcomponent of haemagglutinin (HA1)

Microbiology (Reading). 2001 Apr;147(Pt 4):811-819. doi: 10.1099/00221287-147-4-811.


Haemagglutinin (HA) activity of Clostridium botulinum type A 19S and 16S toxins (HA-positive progenitor toxin; HA(+)-PTX) was characterized. HA titres against human erythrocytes of HA(+)-PTX were inhibited by the addition of lactose, D-galactose, N-acetyl-D-galactosamine and D-fucose to the reaction mixtures. A direct glycolipid binding test demonstrated that type A HA(+)-PTX strongly bound to paragloboside and some neutral glycolipids, but did not bind to gangliosides. Type A HA(+)-PTX also bound to asialoglycoproteins (asialofetuin, neuraminidase-treated transferrin), but not to sialoglycoproteins (fetuin, transferrin). Although glycopeptidase F treatment of asialofetuin abolished the binding of HA(+)-PTX, endo-alpha-N-acetylgalactosaminidase treatment did not. Thus these results can be interpreted as indicating that type A HA(+)-PTX detects and binds to Gal beta 1-4GlcNAc in paragloboside and the N-linked oligosaccharides of glycoproteins. Regardless of neuraminidase treatment, type A HA(+)-PTX bound to glycophorin A which is a major sialoglycoprotein on the surface of erythrocytes. Both native glycophorin A and neuraminidase-treated glycophorin A inhibited the binding of erythrocytes to type A HA(+)-PTX. Since the N:-linked oligosaccharide of glycophorin A is di-branched and more than 50% of this sugar chain is monosialylated, type A HA(+)-PTX probably bound to the unsialylated branch of the N-linked oligosaccharide of glycophorin A and agglutinated erythrocytes. One subcomponent of HA, designated HA1, did not agglutinate native erythrocytes, although it did bind to erythrocytes, paragloboside and asialoglycoproteins in a manner quite similar to that of HA(+)-PTX. These results indicate that type A HA(+)-PTX binds to oligosaccharides through HA1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylgalactosamine / metabolism
  • Botulinum Toxins, Type A / metabolism*
  • Chromatography
  • Clostridium botulinum / metabolism*
  • Electrophoresis, Polyacrylamide Gel
  • Globosides / metabolism
  • Glycolipids / metabolism
  • Glycoproteins / metabolism
  • Hemagglutination Inhibition Tests
  • Hemagglutination Tests
  • Hemagglutinins / metabolism*
  • Humans
  • Immunoblotting
  • Lectins
  • Oligosaccharides / metabolism*
  • Protein Binding


  • Globosides
  • Glycolipids
  • Glycoproteins
  • Hemagglutinins
  • Lectins
  • Oligosaccharides
  • hemagglutinin I
  • paragloboside
  • Botulinum Toxins, Type A
  • Acetylgalactosamine