Part:BBa_K566001

pRM promoter from Lambda

pRM promoter from Lambda phage. It may be positively and negatively regulated according to cI protein concentration (1). Low [cI] induce it, high [cI] repress it. It needs OL region (K566000) for effective repression. Makes the biphasic switch (K566002) together with OL region.

Usage and Biology

pRM promoter transcribes CI, rexA, and rexB in a lysogen. It contains three operators named OR1, OR2 and OR3, all cI binding sites (figure 1). When bound to OR1 and OR2, cI positively regulates pRM; cI binding to OR3 repress pRM. However, due to a low binding affinity to OR3, higher concentrations of the protein are required. Furthermore, OL region -spaced 2.4kb apart- is needed to stabilize cI binding to OR3 through cooperative binding forming a DNA loop (2).

Figure 1. The λ operators OL and OR. The promoter pRM transcribes cI, rexA, and rexB in a lysogen, which sum up to size of ∼2.4Kb. Figure taken and modified from Court DL et al. (2007) J Bacteriol. 189: 298–304.

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  COMPATIBLE WITH RFC[25]
• 1000
  COMPATIBLE WITH RFC[1000]