Abstract
When treated with sulbenicillin, Pseudomonas aeruginosa showed suppressed growth and its cells were elongated into filamentous profiles. These cells were examined for morphology, biochemical properties, and pathogenicity.
1) The bacterial cells underwent no prominent morphological changes, except that they became remarkably elongated.
2) The filamentous cells were less resistant to heat and ultrasonic waves and more sensitive to phenol, lysozyme, and gentamicin than the intact cells.
3) The filamentous cells were actively ingested and destroyed by phagocytes, but they intact cells were not.
4) The filamentous cells were much less pathogenic for mice than the intact cells.
5) Endotoxin of the filamentous cells produced no significant toxic effect, while endotoxin of the intact cells was markedly toxic.
6) The filamentous cells were different from the intact cells in certain biochemical properties and significantly lower in pathogenicity and toxicity than the intact ones. These findings indicate that when used for chemotherapy, sulbenicillin not only exerts a direct bactericidal effect but inhibits bacterial growth and produces additional therapeutic effects.
