PATHOGENICITY OF SALMONELLA IN ENVIRONMENTS

沙门氏菌是日本食源性疾病的主要病原菌之一，10多年来一直是日本食源性疾病的主要病原菌之一，在实验室和环境领域都进行了研究。对一株临床分离的致病性沙门氏菌(Salmonella typhimurium，STM)在不同组成、pH、等价性和盐度的水中的活力进行了检测，发现在静止相生长的STM比在对数生长期生长的更稳定。对东京玉马河河水的调查表明，肠炎沙门氏菌(SE)沿该河流的上游和中游受到污染，所有分离的肠炎沙门氏菌克隆均对感染P.O.的BALB/c小鼠产生毒力。此外，在养鸡场的环境中也分离到了致病性SE，如空气中的粉尘或鸡舍内的墙壁。对这些SE的分析表明，约有1/2的分离克隆对小鼠有致病性，并与大小为20-30 kDa的SE的一系列蛋白条带密切相关。这些结果表明，河水和养鸡场中的大部分(但不是全部)环境SE都具有致病性，其毒力的表达可能受一系列相对分子质量为20-30 kDa的沙门氏菌蛋白的调控，也可能受沙门氏菌的生长阶段的调控。

Pathogenicity of Salmonella, which has been one of the major microbes for food-born diseases in Japan for these more than 10 years, was studied both in laboratory and in environmental fields. Viability of a pathogenic Salmonella of a clinical isolate (Salmonella Typhimurium; STM) was examined in water of different compositions with pH, isotonicity or salt, and found that STM grown in a stationary phase was much more stable than that in a logarithmic phase. Survey of the river water of Tama River in Tokyo revealed that Salmonella Enteritidis (SE) was contaminated along with the up-and middle streams of this river, and that all of the isolated clones of SE shoed virulence to BALB/c mice infected p.o. Furthermore, pathogenic SE was also isolated in environment of chicken farms, such as dust in air or wall of the chicken house. Analysis of these SE showed that about 1/2 of the isolated clones were pathogenic to mice, with close correlation of a series of protein bands of SE of MAW 20-30 kDa. These results suggest that most, but not all, of the environmental SE either in river water or in chicken farm possess pathogenicity, and that the expression of the virulence might be regulated by a series of Salmonella proteins of MW 20-30kDa and also by growth phases of Salmonella.