CYTOCHEMICAL LOCALIZATION OF CATALASE IN LEAF MICROBODIES (PEROXISOMES)

摘要: Segments of mature tobacco leaves were fixed in glutaraldehyde, incubated medium containing 3,3'-diaminobenzidine (DAB) and hydrogen peroxide, postfixed osmium tetroxide. Electron microscopic observation treated tissues revealed pronounced deposition a highly electron-opaque material microbodies but not other organelles. The coarsely granular reaction product is presumably black formed by oxidized DAB with Reaction the was completely inhibited 0.02 M 3-amino-1,2,4-triazole considerably reduced 0.01 potassium cyanide. These results, when considered light recent biochemical studies, strongly suggest that catalase responsible for reaction. Sharp localization this enzyme establishes they are identical to catalase-rich "peroxisomes" recently isolated from leaf cell homogenates. A browning occurred during incubation step cyanide aminotriazole therefore could have been caused same enzyme. This slight dense within primary secondary walls ascribed oxidation soluble wall-localized peroxidases.