| Abstract: | Preparative techniques were developed for the purpose of visualizing, by negative contrast, some of the cytological characteristics of unsectioned cells of Pseudomonas aeruginosa. Concentrated fimbriae free from cells had a length of approximately 1.5 μm and a diameter of 6 nm. Pyocin-like structures ranging in length from 32-64 nm with a width of 8.6 nm were “attached” to the terminal ends of a small percentage of these fimbriae. Microtubules and ringlets having a diameter of 10-20 nm were also visualized in the bacteria. Budding or evagination of cell wall material in multiple units up to 135 nm in length was frequently observed in older cultures grown on agar media. |
