The influence of water-soluble proteins from fungi on the energetic activity of isolated plant mitochondria

The effect of the total water-soluble fungal protein from the mycelium and fruitbodies of two Pleurotus species on the respiration activity of winter wheat mitochondria has been studied. The protein from the frozen (-12 degreesC) mycelium of P. ostreatus cold tolerant strain U2 has uncoupliung effect on the oxidation and phosphorilation in mitochondria as compared to the protein of the same strain, grown at the <<control>> temperature (21 degreesC). The protein of a less tolerant mycelium of the nemoral species had a similar effect, but to a smaller degree. The uncoupling activity of the fluitbody protein in P. ostreatus has not been found. On the contrary, those in P. citrinopileatus had a very high activity. After adding pronase E to the proteins and boiling them the uncoupling effect disappeared. It is assumed that the uncoupling of oxidation and phosphorilation also appeared in fungal mitochondria and it can have positive effect on mycelial adaptation to the freezing stress due to higher temperature of the cells and lower oxidative stress.