Cossart P, Vicente M F, Mengaud J, Baquero F, Perez-Diaz J C, Berche P
Département des Biotechnologies, Institut Pasteur, Paris, France.
Infect Immun. 1989 Nov;57(11):3629-36. doi: 10.1128/iai.57.11.3629-3636.1989.
The role of listeriolysin O in the intracellular multiplication of Listeria monocytogenes and, therefore, its pathogenicity was questioned through a genetic complementation study. A nonhemolytic mutant was generated by inserting a single copy of transposon Tn917 in the bacterial chromosome. This insertion was localized by DNA sequence analysis in hlyA, the gene coding for listeriolysin O. As was another mutant that we previously characterized, this mutant was avirulent in the mouse. It was transformed with a plasmid carrying only hlyA, able to replicate in L. monocytogenes, and stably maintained in vitro and in vivo. The complemented strain displayed a hemolytic phenotype identical to that of the wild-type strain and was fully virulent, therefore attributing a crucial role to listeriolysin O in virulence and excluding the hypothesis of a polar effect of the transposon insertion on genes adjacent to hlyA and possibly involved in virulence.
通过一项基因互补研究，对溶血素O在单核细胞增生李斯特菌细胞内增殖中的作用及其致病性提出了质疑。通过将单拷贝转座子Tn917插入细菌染色体中，产生了一个非溶血性突变体。通过DNA序列分析，该插入定位在编码溶血素O的基因hlyA中。与我们之前鉴定的另一个突变体一样，该突变体在小鼠中无致病性。用仅携带hlyA的质粒对其进行转化，该质粒能够在单核细胞增生李斯特菌中复制，并在体外和体内稳定维持。互补菌株表现出与野生型菌株相同的溶血表型，并且具有完全的致病性，因此归因于溶血素O在毒力中起关键作用，并排除了转座子插入对与hlyA相邻且可能参与毒力的基因产生极性效应的假设。
