Lambda cI QPI w/ strong RBS
Usage and Biology
Preliminary data indicates that this inverter functions well. [jb, 5/24/04]
Sequence and Features
- 10COMPATIBLE WITH RFC
- 12COMPATIBLE WITH RFC
- 21COMPATIBLE WITH RFC
- 23COMPATIBLE WITH RFC
- 25COMPATIBLE WITH RFC
- 1000COMPATIBLE WITH RFC
ECUST_China 2019 characterization
In ECUST_China 2019 characterization, we added the Plac before the CⅠgene and used mRFP as the reporter gene to measure the effectiveness of this part. In the absence of IPTG, CⅠP was constitutively expressed so that the RFP fluorescence could be observed. However, as the concentration of IPTG increasing, Plac was activated to express CⅠprotein which inhibited the transcription of CⅠP ，so the fluorescence of mRFP decreased.
Group: iGEM Team XMU-China 2020
Author: Shi Zhang
Summary: fluorescence / OD600
Quantitative Characterization from iGEM20-XMU-China
Inverter is mainly composed of cI repressor from E. coli phage lambda and pR promoter which is inhibited by cI repressor. It can reverse the inducer action of the upstream promoter. It was registered in 2003.
- Fig.1 Genetic circuits of Inverter.
For the latter circuit, cI repressor will not express in the absence of arabinose so that the fluorescence of EYFP can be observed. At the certain concentration of arabinose, PBad/araC can be activated to express cI repressor to inhibit the pR promoter，so the fluorescence of EYFP decreases.
The fluorescence/OD600 values of these two circuits were measured with or without arabinose and compared with “PBad/araC-pSB1C3” in E.coli BL21(DE3). We discovered that the downstream gene of proBAD/araC can be expressed in the presence of arabinose and decrease expression without arabinose. When the inverter is added to the circuit, the effect is reversed. The result proves that inverter can function correctly and reverse the effect of PBad/araC.