INFLUENCE OF ALUMINUM ON THE MEMBRANES OF MYCORRHIZAL FUNGI

The influence of Al3+ on the membrane fluidity of the mycorrhizal fung us Lactarius piperatus (L. ex. Fr.) S. F. Gray was studied. When mycel ia grew on media supplemented with 1 or 10 mM aluminum for 21 days, a significant increase in fluidity was detected, compared with the corre sponding controls. The comparisons of the EPR spectra calculated by a model, with the experimental ones showed that the spectra are superimp ositions of two components with different membrane ordering. The actio n of aluminum induced a relative enlargement of the less immobilized p ortion in the membrane. No significant alterations of fluidity were me asured after 30-minute treatment, with Al3+.