Difference between revisions of "Part:BBa K1385001"

Revision as of 00:26, 14 October 2014

Hybrid CpcG2 promoter -> TetR

This is BBa_K1385000 with a hybrid cpcG2 promoter created to make leaky/strong expression of tetR.

CpcG2 hybrid promoter: Maintains Upstream region of promoter with G-box, the binding site of CcaR to the promoter. A Phosphorylated CcaR binds to the G-box and transcribes the cpcg2 gene. G-box is a conserved sequence located -108 upstream of TSS

In this case, the g-box works as an activator for the light sensor mechanism.

Replaced downstream (including -35 and -10 regions) with TetR.

Usage and Biology

PcpcG2 is a promoter from the genome of Synechocystis sp. PCC6803. The promoter comes from Jeffrey Tabor's plasmid pJT122 plasmid, contains the entire region upstream of cpcG2 and downstream of ccaR (Tabor et al. 2011). PcpcG2 is regulated by the light-activation of ccaS/ccaR. The gene downstream to this promoter is transcribed upon activation by ccaS/ccaR, via green light.

In our experimental plasmid, the CcaR/CcaS/ CpcG2 promoter/ tetR/Tet promoter/EYFP are all on the same plasmid. I was not able to clone the entire plasmid since it is a modified version of Tabor's PJT122 and the CcaR/CcaS genes had illegal restriction sites, so I decided only to biobrick the promoter with tetR. CcaR/CcaS genes can be found on the registry, as well as tet promoters driving reporter proteins; in my case I decided to use EYFP.

The light activation system is as follows:

This promoter needs to be used in conjunction with the Phycocyanobilin (PCB) which converts Heme and PcyA and Ho1 into the chromophore (why you need to use it with https://parts.igem.org/Part:BBa_K1017726). It also needs the CcaR and CcaS genes in order to function. Therefore you need a part such as https://parts.igem.org/Part:BBa_K360051 to work.

When activated by light, this promoter transcribes an output gene, in this case TetR, creating an inverter mechanism for a gene driven by pTet. In our experimental plasmids we had this in conjunction with a pTet promoter driving a reporter protein.

Sequence and Features

Functional Parameters