Essai de differenciation des souches d’Enterob acteriaceae en fonction de leur origine

Generation times of strains belonging to the Enterobacteriaceae family were determined at 4 °C, 10 °C, 41 °C and 44 °C. Some of these strains originated from humans, the others were isolated from unpolluted media not associated with the human body. According to the generation time two types of enterobacteria could be distinquished: psychrotrophic and mesophilic; the differentiation of the strains according to these designations corresponds to that based on cosiderations of the origin and classification of the organisms. The importance of the determination of an optimal growth temperature for the differentiation of these strains is discussed.