Effects of accumulation of 3-O-methylglucose on growth and osmotic regulation in Chlorella emersonii

Abstract. The effect of accumulation of 3-0- methylglucose (MG) on growth and steady-state concenttations of the endogenous osmotic solutes proline and suerose was studied in Chlorella emer.sonii grown at external osmotic ptessure (fl) of 0.08-1.64 MPa. NaCl was used as ostnoticum. The total solute content of the cells was tnanipulated by supplying 2 mol m*^ MG for 4 and 48 h. MG aceumulated to 50-230 mol m~^ within 4h and was not metabolized. Uptake of MG resulted in decteases in concenttations of pioline and sucrose, the two solutes mainly responsible for osmotic adaptation of C emer.sonii to high n. After 4 or 48 h gtowth in the presence of MG, the decreases in concentration of proline and sucrose were as predicted ftoin the eontribution of MG to the total solute content of the cell.