Norel F, Robbe-Saule V, Popoff M Y, Coynault C
Institut Pasteur, Unité des Entérobactéries, Unité INSERM 199, Paris, France.
FEMS Microbiol Lett. 1992 Dec 1;78(2-3):271-6. doi: 10.1016/0378-1097(92)90039-q.
The virulence of Salmonella typhimurium for mice is dependent on a plasmid-borne gene cluster termed spv. We previously determined that both S. typhimurium and Escherichia coli bacteria grown in a rich medium preferentially express the spv genes during the stationary phase of growth. In this study we evaluated the role of KatF, a putative sigma factor for starvation- and stationary phase-induced genes, in the expression of the spvB gene. The transcription of spvB in E. coli was compared in katF and wild-type backgrounds, using cloned spvB-lacZ and spvB-cat fusions. Expression of spvB was found to be greatly affected in katF mutants. Complementation experiments performed with the cloned katF gene confirmed that KatF is required for the expression of the S. typhimurium virulence gene spvB in E. coli.
鼠伤寒沙门氏菌对小鼠的毒力取决于一个称为spv的质粒携带基因簇。我们先前确定,在丰富培养基中生长的鼠伤寒沙门氏菌和大肠杆菌在生长稳定期优先表达spv基因。在本研究中,我们评估了KatF(一种推测的饥饿和稳定期诱导基因的sigma因子)在spvB基因表达中的作用。使用克隆的spvB-lacZ和spvB-cat融合体,在katF和野生型背景下比较了大肠杆菌中spvB的转录。发现spvB的表达在katF突变体中受到极大影响。用克隆的katF基因进行的互补实验证实,KatF是大肠杆菌中鼠伤寒沙门氏菌毒力基因spvB表达所必需的。