Figure 3.

Electron-lucent PHB granules in transgenic fibers. Cotton fibers (no. 7148, 30 DPA) were fixed with 1% paraformaldehyde/2% glutaraldehyde in 0.05 M phosphate buffer (pH 7.2) for 2 h at room temperature. After washing and fixing, they were embedded in Spurrs epoxy resin. Sections (75–90 nm thick) were then placed on nickel (300 mesh) grids and stained with 2% uranyl acetate followed by Reynolds lead citrate. Transmission electron (JEOL 100C X II) micrographs of cross sections of cotton fibers are shown. Arrows indicate clusters of granules in the range of 0.15 to 0.3 μm. (Bars = 1 μm.)