Toxoid of Pseudomonas aeruginosa exotoxin A generated by deletion of an active-site residue.
Glutamic acid-553 of Pseudomonas aeruginosa exotoxin A (ETA), identified previously as an active-site residue, was deleted by oligonucleotide-directed mutagenesis of the cloned toxin gene in Escherichia coli. The purified mutant toxin was stable, fully immunoreactive, and capable of blocking toxin receptors. ADP-ribosyltransferase and cytotoxic activities were at least 10(6)-fold lower than those of wild-type ETA, and injection of mice with 50 micrograms (equivalent to 400 lethal doses of ETA) produced no ill effects. The mutant toxin elicited high levels of neutralizing anti-ETA antibodies in mice, which protected against a challenge with 100 micrograms of authentic ETA (greater than 600 lethal doses). The mutant protein has the attributes of a toxoid and may be useful as a component of vaccines for individuals at risk for infection by P. aeruginosa.
Lukac
M
M
Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, Massachusetts.
Pier
G B
GB
Collier
R J
RJ
D036002:ADP Ribose Transferases; D000246:Adenosine Diphosphate Ribose / Q000378:metabolism; D000937:Antigen-Antibody Reactions; D001427:Bacterial Toxins; D001665:Binding Sites; D002470:Cell Survival / Q000187:drug effects; D000939:Epitopes; D005098:Exotoxins / Q000235:genetics / Q000276:immunology* / Q000633:toxicity; D066298:In Vitro Techniques; D007739:L Cells; D009154:Mutation; D010430:Pentosyltransferases / Q000235:genetics / Q000276:immunology; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000276:immunology*; D014612:Vaccines / Q000235:genetics*; D014614:Vaccines, Synthetic / Q000235:genetics* / Q000276:immunology; D037521:Virulence Factors; D000097668:Pseudomonas aeruginosa Exotoxin A
D036002:ADP Ribose Transferases; D000246:Adenosine Diphosphate Ribose; D001427:Bacterial Toxins; D000939:Epitopes; D005098:Exotoxins; D010430:Pentosyltransferases; D014612:Vaccines; D014614:Vaccines, Synthetic; D037521:Virulence Factors; D000097668:Pseudomonas aeruginosa Exotoxin A