Miwa Y, Fujita Y
Department of Biotechnology, Faculty of Engineering, Fukuyama University, Japan.
Nucleic Acids Res. 1990 Dec 11;18(23):7049-53. doi: 10.1093/nar/18.23.7049.
The mechanism underlying catabolite repression in Bacillus species remains unsolved. The gluconate (gnt) operon of Bacillus subtilis is one of the catabolic operons which is under catabolite repression. To identify the cis sequence involved in catabolite repression of the gnt operon, we performed deletion analysis of a DNA fragment carrying the gnt promoter and the gntR gene, which had been cloned into the promoter probe vector, pWP19. Deletion of the region upstream of the gnt promoter did not affect catabolite repression. Further deletion analysis of the gnt promoter and gntR coding region was carried out after restoration of promoter activity through the insertion of internal constitutive promoters of the gnt operon before the gntR gene (P2 and P3). These deletions revealed that the cis sequence involved in catabolite repression of the gnt operon is located between nucleotide positions +137 and +148. This DNA segment contains a sequence, ATTGAAAG, which may be implicated as a consensus sequence involved in catabolite repression in the genus Bacillus.
芽孢杆菌属中分解代谢物阻遏的潜在机制仍未解决。枯草芽孢杆菌的葡萄糖酸盐（gnt）操纵子是受分解代谢物阻遏的分解代谢操纵子之一。为了鉴定参与gnt操纵子分解代谢物阻遏的顺式序列，我们对携带gnt启动子和gntR基因的DNA片段进行了缺失分析，该片段已被克隆到启动子探针载体pWP19中。gnt启动子上游区域的缺失不影响分解代谢物阻遏。在通过在gntR基因之前插入gnt操纵子的内部组成型启动子（P2和P3）恢复启动子活性后，对gnt启动子和gntR编码区域进行了进一步的缺失分析。这些缺失表明，参与gnt操纵子分解代谢物阻遏的顺式序列位于核苷酸位置+137和+148之间。该DNA片段包含一个序列ATTGAAAG，它可能被认为是芽孢杆菌属中参与分解代谢物阻遏的共有序列。
