Formation, growth and regeneration of incomplete cell wall in spheroplasts of the blue‐green alga Anacystis nidulans in liquid media

Abstract

Growing cells of blue-green alga, Anacystis niduluns, were treated with lysozymc in osmotically stdbilized mitrient mcdium. Thcir development and regmeration ability was studied in liquid media. During 5 -8 hrs about 95% of cells were converted to osmotically sensitive spheroplasts having a residual wall layer on their surface. The highest viability of spheroplast population was achieved using rgg-white lysozymc for spheroplast preparation and gradual dilution by nutrient medium int;tcad of centrifugation for lysozyme removd. Most of such preparcd spheroplasts survived for 3 days of cultivation in nutrient medium, and started to die gradually from 3 to 10 days. Spheroplasts were growing spherically, about 30% of them were growing for 8 days up to 40-fold increasc in volume. Multiplication of thyliikoid cisternae in growing spheroplasts was proved by freezectqhing. Electron microscopy further revedrd newly synthesized amorphous walls of isodiametrical ,zppearanre by growing sphrroplasts resembling the original cell walls of cells. In liquid media bluc-grccti alga spheroplasts of Anucyatis niduluns can grow for a number of days, however, only regcrieration of incomplete wall occur unable t o promote revcrsioii of spheroplasts to cells.