CELL-SURFACE GLYCOCONJUGATES OF EUGLENA-GRACILIS (EUGLENOZOA) - MODIFICATIONS UNDER POTASSIUM AND MAGNESIUM-DEFICIENCY

Biochemical and ultrastructural examinations on the pellicle of autotr ophically grown Euglena gracilis were carried out after three days und er potassium and magnesium deficiency Cell-surface changes were detect ed by lectin assay. Compared to cells grown in complete medium; defici ent cells become larger in shaper accompanied by rising carbohydrate, chlorophyll and protein content, bind more and other lectin molecules: an increase of mainly galactose and N-acetylgalactosamine receptors w as observed. Investigations with the mucilage stains alcian blue and r uthenium red indicated that mucilaginous material is released under de ficient conditions, whereas the control cells show a strong precipitat e of these stains well inside the cells beneath the pellicle.