Part:BBa_K1412600

Endow the CL-1(E.coli engineered strain) the ability of chemotaxis and quorum sensing

What it is

The composite part enables the chemotaxis of the engineering CL-1 be regulated by AHL and AiiA, which promotes the emergence of quorum sensing and oscillation.

What it does

The luxI promoter drives production of the luxI, aiiA, and CheZ genes. LuxI enzymatically produces a small molecule AHL, which can diffuse out of the cell membrane and into neighboring cells, activating the luxI promoter. AiiA negatively regulates the circuit by acting as an effective protease for AHL. At the beginning, the small colony of individual cells cannot produce enough inducer to activate expression of the luxI promoter. However, once the population reaches a critical density, there is a “burst” of transcription of the luxI promoters, resulting in increasing levels of LuxI, AiiA, and CheZ (and the bacteria will move outward). As AiiA accumulates, it begins to degrade AHL, and after a sufficient time, the promoters return to their inactivated state. The production of AiiA is then attenuated, which permits another round of AHL accumulation and another burst of the promoters.

How to use it in their project

The emergence of quorum sensing and oscillation will cause the periodic expression of CheZ, which will lead to the growth of bacteria radius present cyclical growth. Then we can use it as a biological timer.

protocol

1.Transformation

2.Extract plasmids

3.Digestion

4.DNA gel electrophoresis

5.Gel Extraction

6.Ligation

7.Transformation

8.Extract plasmids

9.Digestion

10.DNA gel electrophoresis

11.Transform the plasmid into CL-1

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  INCOMPATIBLE WITH RFC[21]

  Illegal BglII site found at 1821
  
• 23
  COMPATIBLE WITH RFC[23]
• 25
  COMPATIBLE WITH RFC[25]
• 1000
  INCOMPATIBLE WITH RFC[1000]

  Illegal BsaI.rc site found at 1101
  Illegal BsaI.rc site found at 1970
  Illegal BsaI.rc site found at 3073
  

Reference

[1] [http://www.ncbi.nlm.nih.gov/pubmed/21998392/ Sequential Establishment of Stripe Patterns in an Expanding Cell Population Chenli Liu et al.Science 334, 238 (2011);DOI: 10.1126/science.1209042]

[2] [http://www.ncbi.nlm.nih.gov/pubmed/20090747/ A synchronized quorum of genetic clocks Tal Danino et al. Nature. 2010 Jan 21;463(7279):326-30. doi: 10.1038/nature08753]