Preparation of Metabolically Active Protoplasts and Particle Preparations from the Blue-Green Alga, Phormidium luridum

A method is described for the preparation of metabolically active protoplasts from the blue-green alga, Phormidium luridum. The isolated protoplasts are stable and are capable of endogenous respiration and photoassimilation of carbon dioxide at rates not appreciably different from the untreated filaments. The protoplasts can be ruptured by dilution of the stabilizing osmoticum and, therefore, they provide a convenient starting point for the production of cell-free preparations within a biochemical reaction mixture of interest.