Isolation and characterization of Pseudomonas aeruginosa exotoxin A binding glycoprotein from mouse LM cells

A Pseudomonas aeruginosa exotoxin A (PE) binding glycoprotein was affinity purified from toxin sensitive mouse LM cells. The binding protein was solubilized with Triton X-100 or Nonidet P-40 and purified on a PE-Sepharose affinity column. Polyacrylamide gel electrophoresis yielded a single band with an estimated molecular mass of greater than 300,000 Da. N-Linked carbohydrate was present, accounting for approximately 10% of the total mass of the molecule. The purified protein specifically bound PE. Incubation of purified protein specifically bound PE. Incubation of purified PE binding protein with toxin reduced toxicity to LM cells. We speculate on the role of this toxin binding glycoprotein in the intoxication process.