Part:BBa_K4167660

LacZ generator driven by Plac

This is a β-galactosidase protein generator with strong RBS, driven by Plac promoter. IPTG can bind to the operator site of the promoter to induce β-galactosidase expression. With the different concentration of IPTG, it can express β-galactosidase at different level. With the detection of p-Nitrophenol, the activity of β-galactosidase can be measured.

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]

BBa_K4167660 is a β-galactosidase protein generator with strong RBS, driven by Plac promoter. This promoter is mainly composed of Lac operon containing LacO site. LacI repressor, encoded by LacI gene, can bind with LacO site to inhibit the binding of RNA pol to the promoter, so the genes downstream expression is blocked. Serving as inducer, IPTG can bind with LacI inhibitor, making it detached from LacO site, which enables the transcription of downstream genes. So, the expression of β-galactosidase is regulated by IPTG induction. With the different concentration of IPTG, it can express β-galactosidase at different level.
β-galactosidase can decompose p-Nitrophenyl-β-D-Galactopyranoside to produce p-Nitrophenol. The product has a characteristic absorption peak at 400 nm. The activity of β-galactosidase can be characterized by the change of absorbance value, which is used to determine the activity of β-galactosidase.