The toxic moiety of the Bacillus thuringiensis protoxin undergores a conformational change upon activation
Proteolytic processing of the 133-kDa crystal protein (protoxin) from Bacillus thuringiensis subsp. kurstaki yields a 67-kDa insecticidal toxin. Differential scanning calorimetry was used to investigate whether the toxic moiety in the protoxin molecule has the same conformation as activated toxin. C...
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Published in | Biochemical and biophysical research communications Vol. 179; no. 2 |
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Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
16.09.1991
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Subjects | |
Online Access | Get full text |
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Summary: | Proteolytic processing of the 133-kDa crystal protein (protoxin) from Bacillus thuringiensis subsp. kurstaki yields a 67-kDa insecticidal toxin. Differential scanning calorimetry was used to investigate whether the toxic moiety in the protoxin molecule has the same conformation as activated toxin. Compared to protoxin, toxin gives rise to a more complex endotherm which extends over a 10 degrees C broader temperature range and contains a component occurring at a substantially higher temperature than any unfolding transition in the protoxin endotherm. It is concluded that the toxic moiety undergoes a conformational change upon activation in which the thermal stability of at least one of its domains is significantly increased |
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Bibliography: | 9171294 H10 L72 |
ISSN: | 0006-291X 1090-2104 |