Figure 1

Cell wall poly P staining of wild type and cell wall deficient C. reinhardtii cells. The confocal microscopic pictures show wild type mt⁺ 137c (above) and cell wall deficient cw92 mt⁺ (below) C. reinhardtii cells that are stained with EcPPXc (green: poly P staining, red: chlorophyll, grayscale: corresponding scattered light picture). Specificity of the poly P staining was controlled by competition with soluble poly P (right). The other wild type strains (mt-137c and mt-CC-410) showed similar staining as wild type mt⁺ 137c (not shown). Because staining of the cell wall mutant strains cw92 mt⁺, cw15 mt⁺, cw15 mt^-, cw1 mt^-, cw14 mt⁺ and cwd mt^- led to identical signals, only the cell wall mutant cw92 mt⁺ is shown as representative.