Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
2820270 | Gene | 2006 | 6 Pages |
The expression and regulatory properties of a propionate-regulated overexpression system (Salmonella enterica prpBCDE promoter (PprpB) and positive regulator (prpR)) were evaluated in wild-type S. enterica serovar Typhimurium TR6583 and prpB− or prpD− versions of this strain and compared with the arabinose-regulated T7 expression system. The wild-type strain showed low expression in the absence of propionate and high expression in the presence of propionate under all growth conditions. In 96-well plates and culture tubes, the wild-type strain exhibited a long delay before full induction; the time delay was significantly shorter in shake flasks. The prpD− strain exhibited low expression in the presence of glucose, highly regulatable expression over a wide range of propionate concentrations, and, in contrast to the wild-type strain, fast induction to full expression under all growth conditions. In contrast, the prpB− strain showed very high background expression in both culture tubes and shake flasks.