Effects of aluminum on membrane fluidity of the mycorrhizal fungus Amanita muscaria

The effect of aluminum on the ordering and dynamics of lipid molecules in plasmalemma was studied by electron paramagnetic resonance via the membrane-inserted reporter spin label molecules (methyl ester of 5-doxyl-hexadecanoic acid) in situ in mycelia of the ectomycorrhizal fungus Amanita muscaria . It was found, first, that the plasmalemma is structured into coexistent regions of lipids with different ordering and dynamics, and second, that aluminum stress is accompanied by the corresponding relative decrease of the proportion of the less ordered membrane domains. This effect is opposite to that found previously for Lactarius piperatus , where the membrane responded by an increase of the portion of the less ordered membrane domains. Such qualitatively diverse effects of aluminum at the membrane level is of interest as it coincides with the opposite effect on growth, i. e. inhibition of Amanita muscaria and stimulation of Lactarius piperatus .