Izu H, Kawai T, Yamada Y, Aoshima H, Adachi O, Yamada M
Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Japan.
Gene. 1997 Oct 15;199(1-2):203-10. doi: 10.1016/s0378-1119(97)00368-5.
We characterized the gntT gene encoding a high-affinity gluconate permease of Escherichia coli K-12. Primer extension and lacZ-operon fusion analyses revealed that gntT has one strong and two weak promoters, all of which are regulated positively by cAMP-CRP and negatively by GntR. The weak promoters became constitutive when separated from the upstream region including the strong promoter that overlaps a putative GntR-binding sequence. Gluconate-specific uptake activity was observed with cells harboring the gntT plasmid clone, which was enhanced by the presence of gntK encoding gluconate kinase.
我们对编码大肠杆菌K-12高亲和力葡萄糖酸盐通透酶的gntT基因进行了表征。引物延伸和lacZ操纵子融合分析表明，gntT有一个强启动子和两个弱启动子，所有这些启动子均受cAMP-CRP正调控和GntR负调控。当与包括与假定的GntR结合序列重叠的强启动子的上游区域分离时，弱启动子变为组成型。用携带gntT质粒克隆的细胞观察到葡萄糖酸盐特异性摄取活性，其因编码葡萄糖酸盐激酶的gntK的存在而增强。
