Yurdusev N, Nicolas J L, Ladire M, Ducluzeau R, Raibaud P
Can J Microbiol. 1987 Mar;33(3):226-31. doi: 10.1139/m87-039.
Our purpose was to study bacterial antagonism between a limited number of strictly anaerobic strains and Clostridium perfringens in the intestinal tract of gnotobiotic rodents. Gnotobiotic mice harboring a Bacteroides thetaiotaomicron, a Fusobacterium necrogenes, and a Clostridium sp. strain were protected against pathogenic B, C, and D C. perfringens serotypes. A drastic antagonistic effect of this three-strain association was also observed against a nonpathogenic C. perfringens serotype A (CpA). It was less efficient in gnotobiotic rats than in mice and less efficient in gnotobiotic mice fed an autoclaved diet than in mice fed the same diet sterilized by irradiation. No diffusible inhibitory substances against CpA were detected in feces of gnotobiotic mice harboring the three antagonistic strains, and no nutrient depletion was demonstrated in filtrates prepared from 10-fold diluted feces of these mice. In vitro mixed cultures of the three antagonistic strains failed to inhibit growth of CpA, whereas CpA did not multiply in a 10-fold diluted feces from gnotobiotic mice. A reverse correlation between the initial number of antagonistic strains and the division number of CpA was determined using serially diluted fecal suspensions. Thus, large numbers of viable cells of both antagonistic strains were required to inhibit the target strain in fecal suspensions as was also found in gnotobiotic mice intestines. However, no diffusible inhibitory substance was detectable nor could depletion of growth factors be identified as causing antagonism. Whatever factors that may be responsible for antagonism were found to be influenced by the host and its diet.
我们的目的是研究在无菌啮齿动物肠道中，有限数量的严格厌氧菌菌株与产气荚膜梭菌之间的细菌拮抗作用。携带嗜热栖热放线杆菌、坏死梭杆菌和一种梭菌属菌株的无菌小鼠对致病性B、C和D型产气荚膜梭菌血清型具有抵抗力。还观察到这种三菌株组合对非致病性A 型产气荚膜梭菌（CpA）具有显著的拮抗作用。在无菌大鼠中，其效果不如在小鼠中显著；在喂食高压灭菌饮食的无菌小鼠中，其效果不如在喂食经辐照灭菌相同饮食的小鼠中显著。在携带这三种拮抗菌株的无菌小鼠粪便中，未检测到针对CpA的可扩散抑制物质，并且从这些小鼠10倍稀释粪便制备的滤液中也未证明有营养物质消耗。这三种拮抗菌株的体外混合培养未能抑制CpA的生长，而CpA在无菌小鼠10倍稀释的粪便中不会繁殖。使用连续稀释的粪便悬液确定了拮抗菌株的初始数量与CpA分裂数量之间的反向相关性。因此，在粪便悬液中，需要大量两种拮抗菌株的活细胞才能抑制目标菌株，这在无菌小鼠肠道中也得到了证实。然而，未检测到可扩散的抑制物质，也未确定生长因子的消耗是导致拮抗作用的原因。发现任何可能导致拮抗作用的因素都受宿主及其饮食的影响。
