Part:BBa_K2525021

PsrpR + RBS + PhlF + T

This part contains a promoter that is repressible by the SrpR repressor, which is a high cooperativity repressor (n = 3.2). Further, the pSrpR is placed upstream of the PhlF gene, which again codes for a repressor with high cooperativity (n = 4.5). The high cooperativity of this part is of great significance to synthetic biology, as it can be used to give steeper response curves for repression. Ideally, when we tend to look at genetic elements as digital logic tools, we require steep transitions of protein levels from 0 to 1 or 1 to 0 (representing and ON and OFF state). However, due to various limitations in biological systems, the response is often in the form of a gradient and not a steep curve. Due to its high cooperativity, repressors such as PhlF & SrpR can give a better and steeper curve than most traditional repressors. This is highly desirable. This system can be used with inducible expression of SrpR to inhibit expression of PhlF, which will basically function overall as a buffer gate (an output of 1 when input is 1, and 0 when input is 0), and can be great tools to produce near digital time delays. Further, this system has been implemented as a part of our novel 5 node ring topology square wave oscillator.

Note: This part is the same as BBa_K2525010. However, that part is in a Kanamycin resistance backbone (pSB1K3), while this is in a Chloramphenicol backbone (pSB1C3)

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  INCOMPATIBLE WITH RFC[12]

  Illegal NheI site found at 20
  
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  COMPATIBLE WITH RFC[25]
• 1000
  COMPATIBLE WITH RFC[1000]