Solute Uptake of <i>Acer pseudoplatanus</i> Cell Suspensions during Recovery from Gas Shock

Abstract

Abstract When the ambient atmosphere of Acer pseudoplatanus cells in suspension culture is rapidly changed by opening the culture flasks and gently stirring (‘mild gas‐shock’) or by filtering and suspending in new medium (‘strong gas‐shock’), drastic modifications of the rates of leucine, methionine, glucose, adenine, sulphate and phosphate uptake are observed. Following the gas‐shock, rates of uptake rapidly decrease within a few minutes. Subsequently the rates increase again to the intial level within several hours. The uptake of potassium, which is known to be passively distributed between the medium and the interior of many plant cells, at least at high external concentrations, is apparently independent of gas‐shock. The shock and recovery kinetics are similar for all solutes investigated (except K + ), in particular for different solutes studied in double labelling experiments with the same batch of cells. At the maximum of the after‐effect of shock, i.e. at minimum rates of uptake, uptake shows a highly reduced dependence on temperatures. Gas‐shock probably inactivates, denatures, structurally alters or releases membrane macromolecules engaged in transport. These molecules are then re‐synthesized and re‐incorporated into the membrane during recovery.