Bacillus thuringiensis delta-endotoxin and larval Manduca sexta midgut brush-border membrane vesicles act synergistically to cause very large increases in the conductance of planar lipid bilayers.
Brush-border membrane vesicles prepared from midguts of Manduca sexta larvae were incorporated into planar phospholipid bilayers. Addition of Bacillus thuringiensis delta-endotoxin to the buffered salt solutions bathing these bilayers resulted in large irreversible increases in conductance. At pH 9.6, the smallest toxin-dependent increase in bilayer conductance observed was 13 nS. Similar conductance increases were never observed in the absence of delta-endotoxin or in delta-endotoxin-treated bilayers not containing components of insect brush-border membranes.
Martin
F G
FG
Biology Department, Temple University, Philadelphia, PA 19122.
Wolfersberger
M G
MG
D000818:Animals; D001413:Bacillus thuringiensis; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000494:pharmacology*; D001427:Bacterial Toxins; D004553:Electric Conductivity; D004731:Endotoxins / Q000494:pharmacology*; D006460:Hemolysin Proteins; D006863:Hydrogen-Ion Concentration; D008051:Lipid Bilayers / Q000378:metabolism*; D008081:Liposomes / Q000378:metabolism*; D018402:Manduca; D008871:Microvilli / Q000502:physiology*
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; D008051:Lipid Bilayers; D008081:Liposomes; C030956:insecticidal crystal protein, Bacillus Thuringiensis