Tippetts M T, Robertson D L
Department of Chemistry, Brigham Young University, Provo, Utah 84602.
J Bacteriol. 1988 May;170(5):2263-6. doi: 10.1128/jb.170.5.2263-2266.1988.
The Bacillus anthracis exotoxin is composed of a lethal factor, a protective antigen, and an edema factor (EF). EF is a calmodulin-dependent adenylate cyclase which elevates cyclic AMP levels within cells. The entire EF gene (cya) has been cloned in Escherichia coli, but EF gene expression by its own B. anthracis promoter could not be detected in E. coli. However, when the EF gene was placed downstream from the lac or the T7 promoter, enzymatically active EF was produced. The EF gene, like the protective antigen (pag) and lethal factor (lef) genes, was present on the large B. anthracis toxin plasmid pXO1.
炭疽芽孢杆菌外毒素由致死因子、保护性抗原和水肿因子（EF）组成。EF是一种钙调蛋白依赖性腺苷酸环化酶，可提高细胞内的环磷酸腺苷水平。完整的EF基因（cya）已在大肠杆菌中克隆，但在大肠杆菌中无法检测到其自身炭疽芽孢杆菌启动子驱动的EF基因表达。然而，当EF基因置于lac或T7启动子下游时，可产生具有酶活性的EF。与保护性抗原（pag）和致死因子（lef）基因一样，EF基因存在于炭疽芽孢杆菌大毒素质粒pXO1上。
