Difference between revisions of "Part:BBa K2016005"

BBa_K2016005 is a composite biobrick, which encodes a strong promoter driving constitutive expression of our GFP (BBa_K2016000), followed by an incorporated RyhB binding site contaning the ribosomal binding site, followed by a fully functioning superfolder GFP. Our superfolder GFP was cloned to be operated by RyhB on the RNA interference level. RhyB is an srRNA that is expressed in E.coli and several other bacteria under low iron conditions, it is therefore responsive to iron concentrations within the cell and provides us with a viable tool needed for iron detection. RyhB causes downregulation of sfGFP in low iron conditions, which we see in the form of lowered florescence. Strong or medium promoters were used for expression of gfp on different levels. However, due to difficulties with cloning, only the GFP under control of strong promoter was submitted to the iGEM registry (Medium-RyhB-GFP cloned into pSB1C3 between EcoRI and SpeI sites available upon request). The gene was cloned into pSB1C3 vector as shown on the right.

Usage and Biology

Our composite biobrick was used for detection of changes in concentration of intracellular iron in E. coli. Our part showed to be responsive to changes in iron concentrations in WT (W3110) E. coli, as well as siderophore-production deficient mutant - JC28 (∆entC). In the figure below we can see differences in the GFP fluorescence when expressed using a medium promoter (J23106 derivative) or strong promoter (J23100 derivative) in two different strains: W3110 (WT) and JC28 (∆entC).

In another experiment we showed changes in GFP fluorescence after addition or iron and followed its expression for 1.5h. In a figure below we show that GFP is significantly overexpressed after addition of iron in all RyhB-GFP strains. Read in detail about our experiments.

Sequence and Features

Functional Parameters