A broad-spectrum cytolytic toxin from Bacillus thuringiensis var. kyushuensis.
Bacillus thuringiensis (Bt) var. kyushuensis synthesizes a mosquitocidal crystalline inclusion containing several proteins ranging from 140 to 14 kDa. We have identified a 25 kDa protein protoxin in this inclusion which is not cytolytic, but when activated proteolytically to 23-22 kDa products is cytolytic to mosquito, lepidopteran and mammalian cells, can release entrapped glucose from liposomes and forms cation-selective channels in a planar lipid bilayer. This broad-spectrum cytolytic toxin is related antigenically to the 23 kDa toxin from Bt var. darmstadiensis strain 73-E10-2, but not to the 25 kDa CytA toxin of Bt var. israelensis. The cytolytic activity of these Bt var. kyushuensis toxins, like that of the latter two toxins, can be neutralized by incubation with liposomes containing phospholipids.
Department of Zoology, University of Cambridge, U.K.
B H
BH
Knowles
P J
PJ
White
C N
CN
Nicholls
D J
DJ
Ellar
D000330:Aedes / Q000187:drug effects*; D000818:Animals; D001413:Bacillus thuringiensis; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000302:isolation & purification / Q000494:pharmacology / Q000633:toxicity*; D001427:Bacterial Toxins / Q000633:toxicity; D002417:Cattle; D002460:Cell Line; D004591:Electrophoresis, Polyacrylamide Gel; D004731:Endotoxins; D004912:Erythrocytes / Q000187:drug effects; D006460:Hemolysin Proteins; D006461:Hemolysis; D007313:Insecta / Q000187:drug effects*; D008051:Lipid Bilayers; D008970:Molecular Weight; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; D008051:Lipid Bilayers; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; C030956:insecticidal crystal protein, Bacillus Thuringiensis