Accumulation of Extracellular Amino Acids by Euglena gracilis

SYNOPSIS. Normal Euglena gracilis , strain z, growing in the light in defined medium (initial nitrogen concentration 140 μ/ml) depletes the medium of all ninhydrin‐positive N by the time a cell density of 2 million per ml is reached. A further 2‐ to 3‐fold increase in the cell number takes place in the absence of exogenous N. The N content of an early log phase cell is about 100 picograms but decreases very rapidly as the culture continues to …