Difference between revisions of "Part:BBa K1051208"

Revision as of 04:42, 3 October 2013

The degradation tag in E. coil ,M0052 with TAATAA.

Purpose

SsrA degradation tag in E. coli, add TAATAA to C-terminal of Biobrick M0052.

Principle

SsrA degradation tag. In E. coli, the adaptor SspB tethers ssrAtagged substrates to the ClpXP protease, causing a modest increase in their rate of degradation. Which means, a variation of the WT SsrA tag sequence will accelerate the degradation of proteins when fused to their C-terminal. Thus the degradation rates are dependent on concentration of proteases and binding mediators. In order to fuse degradation tags freely on the C-terminal of protein, we add TAATAA to the tail of M0052 to construnt this part.
We constructed the measurement pathway of tag K1051259(contains J04500, K1051000 and K1051208) to test the rates of degradation of tagged proteins. J04450 was used as positive control because of the same promoter and fluorescent protein.

Measurement

The growth curve of E. coli. From right to left, the negative control,BBa_K1051257, BBa_K1051258, BBa_K1051259, J04450 as Positive Control. As the pictures showed, the lights of RFP within three degradation tags are decreasing. The test results of BBa_K1051258. A:No exciting lights; B. Powerful exciting lights; C. Weak exciting lights. In picture, there are only obvious lights in the picture B, indicated the degradation rates are working The test results of BBa_K1051258 in chip. A,LB medium,O minuts; B, IPTG medium,9minutes; C,IPTG medium, 15 minutes

The average fluorescence intensity of K1051258 when added IPTG after specific time.
The fluorescence intensity and degradation rate of E. coli.
The data we calculated from microscope and microfluidic mate very well.

Sequence and Features

References

[1]McGinness, Baker, Sauer. 2006. Mol. Cell. 22:701.
[2]Flynn et al 2003. Mol. Cell. 11: 671. Flynn et al. 2001. PNAS 98(19): 10584. Anderson et al 1998. App. Env. Microbiol. 64(6):2240