鼠疫菌Pgm因子在阿拉善黄鼠体内的突变试验观察

用阿拉善黄鼠(Citellus alsachanicus)鼠疫疫源地的鼠疫菌Pgm~+和Pgm~-株,连续通过阿拉善黄鼠进行传代试验。在传代前后用阿拉善黄鼠测其毒力。Pgm~+株连续传代15代后未发现突变,其主要生化特性、抗原结构和毒力都没有发生改变。而含有0.1～0.3％Pgm~+鼠疫菌个体的Pgm~-株在连续传代5代后即突变为Pgm~+株,且毒力增强。但生化特性和抗原结构仍无改变。纯系Pgm~-株在连续传代8～11代后可突变为Pgm~+株,至20代仍未完全突变为Pgm~+,其他生化特性和抗原结构亦没有改变,但其毒力逐渐增强。作者分析鼠疫菌Pgm细胞突变与阿拉善黄鼠动物鼠疫流行和间歇有密切关系,这对研究该疫源地内鼠疫菌的保存机制及流行病学分析提供了参考资料。

IN VIVO MUTATIONS OF Pgm FACTORS OF Y.PESTIS IN CITELLUS ALASCHANICUS

Pgm+ and Pgm- strains of Y. Pestis from a plague focus were successively propagated in Citellus alaschanicus with virulent determination before and after each passage. No remarkable changes in biochemical characters, antigenic structure and virulence were found in the Pgm+ strains after 5 generations of propagation while mutation to Pgm+ and increase of virulence were found in the strains of Pgm- with 0.1-0.3% Pgm+ cells mixed in. The biochemical characters and antigenic structure of the latter, however, did not change. And the pure Pgm-strains became Pgm+- strains after 8-11 passages and they became more virulent gradually without any biochemical and antigenic changes. It is suggested that mutations of Pgm cells are closely correlated with the prevalence and intermittence of the epizootic in C. alaschanicus and this may contribute to the analysis on the existing mechanism of Y. pestis.