Popis: |
SUMMARY: The effects of temperature and the surfactant Tween 80 on the secretion of invertase by the ascomycete fungus Newospora crassa and its wall-less strain slime were investigated. Temperature acclimation dramatically affects the phospholipid fatty acid pattern in both strains. The levels of polyunsaturated fatty acids in membrane lipids of wild-type Neurospova crassa and slime increased as growth temperature decreased. Chromatogram analysis from cultures acclimated to 15 °C showed high levels of linolenic acid (18:3), and low levels of oleic acid (18:1), suggesting desaturation. Reducing the temperature during growth to 15 °C affected phospholipid fatty acid composition in both strains, which resulted in a higher level of invertase secretion. The wild-type Newospora crassa showed no difference in invertase secretion in the presence of Tween 80. However, the addition of the surfactant to slime cultures caused a 60 % increase in invertase secretion, which was more evident after 48 h incubation. |