Caulobacteria were induced for 1 hour at 30 degrees C, labeled in M2G medium for 2 hours at 30 degrees C (in the presence of 1.8 micromolar ReAsH-EDT2) and photoconverted. Samples were fixed with 2.5% glutaraldehyde with 1% acrolein in 0.05M sodium cacodylate pH 7.4 with 3 mM CaCl2 and 1 % sucrose followed by conventional osmium tetroxide/potassium ferrocyanide post-fixation, dehydration and embedding, and sectioning at 4µm thickness. A single tilt series of images were acquired using a JEOL 4000, from -60 to 60° at 2° increments, magnification, 40000.0.