Permeability and membrane lipid metabolism of Phaseolus vulgaris infected with Uromyces phaseoli II. Changes in lipid concentration and 32P incorporation into phospholipids

Abstract

Phospholipids and glycolipids of rust-infected leaf halves and uninfected halves of the same leaves were quantitatively determined and compared with the lipids of healthy primary leaves of bean plants. The phosphatidyl-choline, phosphatidyl-ethanolamine, phosphatidylinositol and sulphoquinovosyl diglyceride (SL) content of the infected halves was the same as in the control plants. The infected tissue showed a decrease in monogalactosyl diglyceride (MGG), digalactosyl diglyceride (DGG) and phosphatidyl-glycerol (PG) and an increase in phosphatidyl-serine (PS) and phosphatidic acid content. These differences were localized mainly in the region of the pustule and not in the surrounding mycelium-free tissue. The amount of all phospholipids and glycolipids in the uninfected leaf halves was slightly lower than in the controls. The ungerminated and germinated uredospores of the parasite contained no MGG, DGG, SL or PG. The infected half leaves showed an increase in 32P incorporation into all phospholipids especially into PS. The differences in 32P-incorporation between the phospholipids of the uninfected half leaves and the controls were only small. These results were discussed in relation to permeability changes of rust-infected bean tissue.