Protoplast isolation involves removing the cell wall from plant cells to leave only the plasma membrane and intracellular components. The isolated protoplasts can be cultured and genetically manipulated. There are two main methods for isolating protoplasts - mechanical and enzymatic. The enzymatic method uses enzymes like cellulase and pectinase to break down the cell wall. Isolated protoplasts are purified through centrifugation and cultured in an osmotic medium to prevent bursting due to the lack of a cell wall. Protoplasts are useful for studies in cell fusion and genetic transformation.