Protoplast induction in Chlorella vulgaris

Cells of the unicellular green alga Chlorella vulgaris formed osmotically fragile protoplasts when incubated for 4–6 h in a defined medium plus 0.4 M mannitol plus 0.5% Cellulysin. The protoplasts were extruded through breaks in the cell wall and not by dissolution of the wall. Protoplasts kept in the inducing medium remained bright green for several days and tended to adhere into chains, rings or clusters. Budding of protoplasts was also observed.