Inactivation of gamma-hemolysin H gamma II component by addition of monosialoganglioside GM1 to human erythrocyte.
The Staphylococcal toxins leukocidin and gamma-hemolysin consist of two protein components: F and S in leukocidin and H gamma I and H gamma II in gamma-hemolysin. The two toxins share one component (F = H gamma I). We found that the H gamma II component was completely inactivated by the addition of monosialoganglioside GM1 at the molar ratio of 1:1. Disialogangliosides GD1a and GD1b had little effect on the inactivation of H gamma II. The molar ratios of GD1a and GD1b to H gamma II needed for maximum inactivation were 30:1 and 100:1, respectively. Related glycolipids caused little if any inactivation. H gamma II bound to GM1 to form H gamma II-GM1 complexes. Analysis of the intrinsic aromatic amino acid fluorescence in H gamma II and H gamma II-GM1 with 280 nm as the excitation wavelength showed that GM1 in the complex reduced the fluorescence intensity of H gamma II by 12% without changing the wavelength of maximum emission (325 nm). We concluded that GM1 is a receptor of the H gamma II component on human erythrocytes and that H gamma II takes on a different conformation when it binds to GM1.
Ozawa
T
T
Department of Applied Biological Chemistry, Faculty of Agriculture, Tohoku University, Sendai, Japan.
Kaneko
J
J
Nariya
H
H
Izaki
K
K
Kamio
Y
Y
D000595:Amino Acid Sequence; D001426:Bacterial Proteins; D001427:Bacterial Toxins / Q000037:antagonists & inhibitors*; D015153:Blotting, Western; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism*; D005677:G(M1) Ganglioside / Q000494:pharmacology*; D006460:Hemolysin Proteins / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D007956:Leukocidins / Q000032:analysis; D008969:Molecular Sequence Data; D011485:Protein Binding; D011487:Protein Conformation; D013050:Spectrometry, Fluorescence
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D006460:Hemolysin Proteins; D007956:Leukocidins; C037956:gamma-hemolysin, Staphylococcus aureus; D005677:G(M1) Ganglioside