Difference between revisions of "Team:SCAU-China/Improve"

Improve

(4) BBa_K2559005 /BBa_K2559009

The part BBa_K2559006 has a sequence improvement on the basic part submitted by iGEM07_Peking (BBa_l714891) which encodes the SDY_eGFP. However, we found out a 16 bp nucleotides redundancy in the eGFP starting coding region in BBa_I714891, after checking the sequence of BBa_I714891 from NCBI. Therefore, we decided to delete the redundant 16 bp nucleotides in BBa_I714891 to amend the length of eGFP coding sequence. The amended eGFP coding biobrick is the BBa_K2559005.

To test the function of BBa_K2559005, we designed a new E.coli expression vector containing our new part termed as BBa_K2559003under a strong E.coli endogenous promoter (PrplJ). Therefore, the amended eGFP in BBa_K2559005 was driven by PrplJ promoter, and expressed in DH10B. In addition, we also applied the BBa_K2559005 in the promoter intensity analysis of our other two new parts, the BBa_K2559004 and BBa_K2559011 which are relatively weaker E.coli endogenous promoters (PdapA and PcaiF) (Figure 1).

Figure 1: Fluorescent intensity of amended eGFP driven by by PrplJ, PdapA, PcaiF promoter.

We summarized that our improvedpart, the amended eGFP coding biobrick BBa_K2559005 worked well in DH10B. We also hoped that our improvement on the BBa_I714891 can help their future applications by other groups in the future. However, it is difficult for us to perform additional experiments with BBa_K2559005 and BBa_I714891 due to the unavailable BBa_I714891.

To expand the application of BBa_K2559005, we searched theBBa_J04450stored in registry and do another improvement in the BBa_J04450. The BBa_J04450 is a strong RFP expression vector in E.coli. As the main page of BBa_J04450 mentioned, the E.coli colonies with BBa_J04450 were in red color under normal light after about 18 hour culture on LB plate (Figure 2). We used the BBa_K2559005 to replace the RFP region in BBa_J04450, the modified part is BBa_K2559009. We transferred the BBa_K2559009 to DH5α by heat-shock, and found that the fluorescence signal can be observed under the UV (Figure 2).

Figure 2 Colonies with BBa_J04450 (red colony) and BBa_K2559009 (green colony) visualized under UV lightbox.

So, we confirm that our improved part BBa_K2559005 can work in different E.coli expression system. We are also looking forward to more application of the BBa_K2559009!