Regulatory
lacI+pL

Part:BBa_R0011

Designed by: Neelaksh Varshney, Grace Kenney, Daniel Shen, Samantha Sutton   Group: Antiquity   (2003-01-31)

Promoter (lacI regulated, lambda pL hybrid)

Inverting regulatory region controlled by LacI (BBa_C0010, BBa_C0012, etc.) The PLlac 0-1 promoter is a hybrid regulatory region consisting of the promoter P(L) of phage lambda with the cI binding sites replaced with lacO1. The hybrid design allows for strong promotion that can nevertheless be:

  • repressed by LacI, the Lac inhibitor (i.e. repressor) (BBa_C0012) ([LUTZ97]).
  • induced by IPTG in E.Coli DH5-alpha-Z1 (same paper reference) over a >600-fold range

Intrinsic Noise Value: 0.0040 (compare with R0010: 0.0707; R0051: 0.0869). See William_and_Mary iGEM 2015


>Internal Priming Screening Characterization of BBa_R0011: Has no possible internal priming sites between this BioBrick part and the VF2 or the VR primer.

The 2018 Hawaii iGEM team evaluated the 40 most frequently used BioBricks and ran them through an internal priming screening process that we developed using the BLAST program tool. Out of the 40 BioBricks we evaluated, 10 of them showed possible internal priming of either the VF2 or VR primers and sometime even both. The data set has a range of sequence lengths from as small as 12 bases to as large as 1,210 bases. We experienced the issue of possible internal priming during the sequence verification process of our own BBa_K2574001 BioBrick and in the cloning process to express the part as a fusion protein. BBa_K2574001 is a composite part containing a VLP forming Gag protein sequence attached to a frequently used RFP part (BBa_E1010). We conducted a PCR amplification of the Gag-RFP insert using the VF2 and VR primers on the ligation product (pSB1C3 ligated to the Gag + RFP). This amplicon would serve as template for another PCR where we would add the NcoI and BamHI restriction enzyme sites through new primers for ligation into pET14b and subsequent induced expression. Despite gel confirming a rather large, approximately 2.1 kb insert band, our sequencing results with the VR primer and BamHI RFP reverse primer gave mixed results. Both should have displayed the end of the RFP, but the VR primer revealed the end of the Gag. Analysis of the VR primer on the Gag-RFP sequence revealed several sites where the VR primer could have annealed with ~9 - 12 bp of complementarity. Internal priming of forward and reverse primers can be detrimental to an iGEM project because you can never be sure if the desired construct was correctly inserted into the BioBrick plasmid without a successful sequence verification.


Usage and Biology

Strong promoter. [jb, 5/24/04]

R0011 will be on in strains without lacI, off in strains that are lacIq (ie. Part:BBa_V1003) and medium in strains that are lacI

Sequence and Features

Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    COMPATIBLE WITH RFC[1000]


[edit]
Categories
//rnap/prokaryote/ecoli/sigma70
//direction/forward
//chassis/prokaryote/ecoli
//promoter
//regulation/negative
//classic/regulatory/uncategorized
Parameters
negative_regulators1
positive_regulators