Braz Vânia S, Marques Marilis V
Department of Microbiology, Institute of Biomedical Sciences, Universidade de São Paulo, Av. Prof. Lineu Prestes, 1374 São Paulo, SP 05508-900, Brazil.
FEMS Microbiol Lett. 2005 Oct 15;251(2):289-95. doi: 10.1016/j.femsle.2005.08.013.
A transposon library of 5700 mutants was constructed in Caulobacter crescentus strain NA1000. Thirteen mutant strains were isolated that presented growth deficiency in the presence of 20 microM cadmium chloride, and the disrupted genes were identified by DNA sequencing. Among the predicted products were found two putative transcriptional regulators, one histidine kinase/response regulator hybrid protein, two 2Fe-2S family proteins, and also members of a putative metal efflux system. Certain of these mutants also showed an increased sensitivity to zinc and copper, and the genes encoding the efflux system were induced by cadmium and zinc, indicating that this system may be important for homeostasis of both metal ions.
在新月柄杆菌NA1000菌株中构建了一个包含5700个突变体的转座子文库。分离出13个在20微摩尔氯化镉存在下生长缺陷的突变菌株，并通过DNA测序鉴定了被破坏的基因。在预测产物中发现了两个假定的转录调节因子、一个组氨酸激酶/反应调节因子杂交蛋白、两个2Fe-2S家族蛋白，以及一个假定的金属外排系统的成员。其中一些突变体对锌和铜也表现出更高的敏感性，并且编码外排系统的基因被镉和锌诱导，这表明该系统可能对两种金属离子的稳态很重要。
