Effects of the Salts Containing Bivalent Anions and of the Temperatures on Flagellation of Cells in Yersinia enterocolitica

Several conditions for flagellation of cells in 5 strains of Yersinia enterocolitica were investigated. Especially, temperature, culture media with salts contained the bivalent anion and incubation period were examined. The data were analyzed statistically and the results were summarized as follows : 1) The cultural temperatures at 27℃ and 37℃ showed a remarkable difference for flagellation on the nutrient agar, the former was always excellent and the latter was far worse than the former. However, addition of salts with the bivalent anion into the media had made no difference between them, showing a good result for the latter. 2) Three kinds of salts with the bivalent anion, such as Na_2CO_3, Na_2HPO_4 and Na_2SO_4 were proved to be effective for flagellation of cells of Yersinia in the culture media by adding of those, even at 37℃ of incubation temperature. 3) The optimal pH for flagellation was variable in each medium, according to the containing grade of salt and culture temperature. In general, the most optimal pH was found between 5.2 and 7.4 at 27℃, and 5.4 and 7.4 at 37℃, respectively. 4) Twenty four and 48 hours of incubation periods showed no difference for flagellation under the conditions of the two different temperatures and of contained salts. The medium with Na_2SO_4 showed some prolongation for flagellation. 5) Variable numbers of flagella were observed in each strain of Yersinia, between 1 and 3 per cell on the medium with salt. 6) Strains used in the experiment showed some differences. Especially, strains except 03B4 group, showed a decrease of the flagellated cells on the medium with Na_2SO_4.