Culture of Chlamydomonas reinhardi Protoplasts in Defined Media

Abstract

The cell-wall-deficient mutant CW15-9 of C. veinhavdi was grown in defined medium in suspension culture and on agar. Plating efficiencies of up to 95 % were achieved, even at low cell densities. In suspension culture, the correlation between cell number and absorbance over a large part of the growth cycle allowed easy monitoring of cell growth and division. Colony morphology on agar was flat, allowing microscopic observation of individual cells. Protoplasts grown in the absence of mannitol as an osmotic protectant did not burst, which suggests that the osmoregulation mechanism of the wild type has been retained by CW15 cells. Algal protoplasts have advantages as a model system for the study of higher plant protoplasts and cells in culture.