溶血毒産生に於ける二菌の相互作用

第1編 動物通過による溶血性の変化 第2編 人工培地に於ける溶血毒産生 第3編 静止菌に於ける溶血毒産生

抄録

With the use of Staph. aureus (au), Staph. albus (al), Str. hemolyticus (hem), D. peumoniae (p), A. aerogenes (aer) and M. luteus (M), all of those were obtained from the departmental stock, the author investigated the difference in the variation of hemolytic feature of bacteria through mice passage by mean of comparison between one species inoculation of bacteria and two species mixed inoculation. The following results were obtained.
1) Mixed inoculation of au and hem into abdominal cavity of mouse showed increase of virulence, and exhibited increased asthenia of animal and higher death rate in comparison with the inoculation of either species of them. Contrarily, in the combination of au and p the virulence of bacteria was decreased, hence two species competed in their virulence.
2) After the hypodermic inoculation on the back of mouse au increased its hemolytic virulence by a short time passage of animal; however, its virulence markedlp increased when it was inoculated with hem, p, or M.
Using standard strains of the microoragnisms described, the author studied the interaction between two species of bacteria on growth in blood-added or non-added fluid media and on hemolysin production. The following results were obtained.
1) Various combinations of two species of bacteria, in which one was au or al the other was taken out of hem, p, aer, or M, were made and cultured in the fluid media described above. From the results of culture, it was noticed that the growth of bacteria in combination of two species was inhibited and the hemolysin production by them was reduced compared with pure culture of either species.
2) When a species cultured in the media contained the cell free supernatant in which the other species was cultured previously, the growth of bacteria and their function of hemolysin production generally tended to inhit compared with the controll.
3) These facts presumably showed that both species of bacteria in combination produced substances that showed the inhibitory effect on the growth and the hemolysin production of other species, and that the hemolysin produced by a species was turned inactive by other species.
Using the resting cells of the microorganisms described, the author observed the interaction of two species of bacteria on their hemolysin production, and obtained the following results.
1) When a suspension of restiing cells was shaken after the addition of peptone into the media, aur showed the increased production of hemolysin: hem, p, al showed only slight production; while aer, M did not produce it.
2) Hemolysin production in the mixed suspension of aur and hem, and of aur and p was increased compared with the single cell suspension. On the other hand, the hemolysin production was decreased in the combination of aur and aer and of aur and M.
3) The hemolysin produced by aur was turned inactive by shaking with the other bacteria; on the other hand the hemolysin production of aur was increased by the shaking with the cell free supernatant of the other bacteria.
4) Presumably, it was concluded that the interaction between two species of bacteria on hemolysin production included two ways, one was accelratory and the other inhibitory, and they could be observed only in over-all state depending on their environment.