Difference between revisions of "Part:BBa K1025006"

Revision as of 16:56, 18 September 2013

_ Bitter Defender Part （RBS_B0030）

iGEM bitter pressure part(RBS_B0030) is a plasmid constructed by 2013 iGEM Tsinghua-E team which is used for providing of selection pressure for the evolution and enrichment of tryptophan overproduction microorganism phenotype. It is almost the same with iGEM bitter pressure part(RBS_B0032)（BBa_K1025007） except for the second RBS.

Usage and Biology

This selection pressure was based on the tryptophan dependent tetracycline antiporter expression which functioned in tetracycline culture condition. It is achieved by cloning E.coli tetracycline antiporter gene (tetA) downstream of our previously constructed tryptophan biosensor which is controlled by tac promoter between NcoI and BamHI restriction sites in pTrc99A vector. We constructed three bitter pressure part by utilizing three different RBS upstream of tetA gene. We transformed these vectors into three previously engineered E.coli with different tryptophan productivity (unpublished data).

Functional Parameters

The tryptophan productivity of these nine strains (three RBS and three previous productivities) was further confirmed by HPLC after culture in M9YE medium for nearly 25h after 0.1mM IPTG induction.

Sequence and Features