Ij. Xavier et Gg. Khachatourians, HEAT-SHOCK RESPONSE OF THE ENTOMOPATHOGENIC FUNGUS BEAUVERIA-BRONGNIARTII, Canadian journal of microbiology, 42(6), 1996, pp. 577-585
The heat-shock response of five strains of the entomopathogenic fungus
Beauveria brongniartii was studied using two-dimensional (2D) gel ele
ctrophoresis. The fungal cells were heat shocked at 45 degrees C for 1
h and the total cellular protein was subjected to 2D gel electrophore
sis. Proteins were separated in the first dimension using isoelectric
focusing (pH range of 3.0-10) and in the second dimension by sodium do
decyl sulphate - polyacrylamide gel electrophoresis. More than 150 pol
ypeptides for each strain were visualized by silver staining and have
been assigned individual numbers as polypeptide coordinates. Analysis
of the polypeptide map obtained by 2D gels indicated three patterns; s
everal unique heat-shock proteins (HSPs) were (i) induced, (ii) enhanc
ed, or (iii) repressed. Some of the HSPs induced by 45 degrees C were
unique for each of the strains tested. Identification of heat-inducibl
e protein synthesis or repression has ramifications for field survival
and performance of entomopathogenic fungi. As well, the HSPs can be u
sed as ''signature proteins'' for identification pruposes and this rai
ses the possibility of using HSPs as a diagnostic tool applicable to o
ther pest control fungi.