DNA homology and immunological cross-reactivity between Aeromonas hydrophila cytotonic toxin and cholera toxin.
DNA colony hybridization with three 18- to 20-base-long synthetic oligonucleotide probes for cholera toxin (CT) was used to screen 12 clinical isolates of Aeromonas hydrophila. Under stringent hybridizing (overnight at 40 degrees C) and washing (1 h at 50 degrees C) conditions, nine strains reacted with the 32P-labeled CT probes. Concentrated (10x) cell-free supernatants or lysates from eight cultures, heated at 56 degrees C for 20 min, produced cytotonic effects in Y-1 mouse adrenal cells and Chinese hamster ovary (CHO) cells and caused a 1.5- to 22-fold increase in production of cyclic AMP in CHO cells. Preincubation with anti-CT reduced the CHO cell titer of cell lysates by 10-fold. In the GM1 ganglioside enzyme-linked immunosorbent assay, heated supernatants and lysates gave readings equivalent to 3.5 to 100 ng of CT. Three proteins with molecular weights of 89,900, 37,000, and 11,000 reacted with anti-CT on immunoblots of cell lysates from sodium dodecyl sulfate-polyacrylamide gels. These results suggest that there is DNA homology and immunological cross-reactivity between CT and the A. hydrophila cytotonic toxin.
Schultz
A J
AJ
Division of Microbiology, Food and Drug Administration, Washington, D.C. 20204.
McCardell
B A
BA
D000333:Aeromonas; D001427:Bacterial Toxins / Q000235:genetics* / Q000276:immunology / Q000633:toxicity; D002772:Cholera Toxin / Q000235:genetics* / Q000276:immunology / Q000633:toxicity; D003429:Cross Reactions; D000242:Cyclic AMP / Q000378:metabolism; D003603:Cytotoxins / Q000235:genetics* / Q000276:immunology / Q000633:toxicity; D004269:DNA, Bacterial / Q000235:genetics; D009693:Nucleic Acid Hybridization; D012689:Sequence Homology, Nucleic Acid
D001427:Bacterial Toxins; D003603:Cytotoxins; D004269:DNA, Bacterial; D002772:Cholera Toxin; D000242:Cyclic AMP