a bacteria population-control device with lux pR-3 driven by lacl+pL
This device is made up of three subparts: a LuxI producer, a LuxR producer and a killer protein producer. It is designed to build a programmed bacterial death circuit, which is based on the quorum sensing system of Vibrio fischeri. iGEM-Team XMU-China has generated 7 bacteria population-control devices using RBSs of different strength and different lux pR mutants. This device has the ability to maintain cell density of the bacteria population at a relatively low value compared with bacteria without this circuit and extends the stable state. Lux pR-3(BBa_K658006) was used to regulate the expression of killer protein LacZalpha-ccdB.
This device is based on BBa_K658001. The mutated promoter lux pR-3 in the killer protein producer regulate the expression of killer protein LacZalpha-ccdB. The strength of promoters lux pR and its 3 mutants lux pR-3, lux pR-5, lux pR-3/5 were tested before they were used as regulators in a circuit. The strength of the lux pR-3 is related to the expression of the killer protein LacZalpha-ccdB. The higher strength a lux pR has, the lower cell density may be got in the steady state.
RBS (Elowitz 1999) -- defines RBS efficiency
Varies from -6 to +1 region from original sequence to accomodate BioBricks suffix. No secondary structures are formed in the given RBS region. Users should check for secondary structures induced in the RBS by upstream and downstream elements in the +50 to -50 region, as such structures will greatly affect the strength of the RBS. Contact info for this part: Brian Chow
Vinay S Mahajan, Voichita D. Marinescu, Brian Chow, Alexander D Wissner-Gross and Peter Carr IAP, 2003.
Derived from the TE terminator of T7 bacteriophage between Genes 1.3 and 1.4 <genbank>V01146</genbank>.
Transcription terminator for the E.coli RNA polymerase.
Suggested by Sri Kosuri and Drew Endy as a high efficiency terminator. The 5' end cutoff was placed immediately after the TAA stop codon and the 3' end cutoff was placed just prior to the RBS of Gene 1.4 (before AAGGAG). Use anywhere transcription should be stopped when the gene of interest is upstream of this terminator.
Transcriptional terminator consisting of a 64 bp stem-loop.
RBS.1 (strong) -- modified from R. Weiss
Strong RBS based on Ron Weiss thesis. Strength is considered relative to <bb_part>BBa_B0031</bb_part>, <bb_part>BBa_B0032</bb_part>, <bb_part>BBa_B0033</bb_part>.
Varies from -6 to +1 region from original sequence to accomodate BioBricks suffix ("orig" in figure 4-14 of Ron Weiss thesis). No secondary structures are formed in the given RBS region. Users should check for secondary structures induced in the RBS by upstream and downstream elements in the +50 to -50 region, as such structures will greatly affect the strength of the RBS. Contact info Brian Chow
V. fischeri <genbank>AF170104</genbank>
In complex with HSL, LuxR binds to the Lux promoter, activating transcription from Pr <bb_part>BBa_R0062</bb_part>, and repressing transcription from Pl <bb_part>BBa_R0063</bb_part>. The lux cassette of V. fischeri contains a left and a right promoter. The right promoter gives weak constitutive expression of downstream genes.This expression is up-regulated by the action of the Lux activator, LuxR complexed to HSL. Two molecules of LuxR protein form a complex with two molecules the signalling compound homoserine lactone (HSL). This complex binds to a palindromic site on the promoter, increasing the rate of transcription.
2 silent point mutants were introduced in the coding sequence to remove internal XbaI and PstI sites. Mutation sites were chosen to replace codons commonly used in E. coli with codons used at a similar frequency.
Vinay S Mahajan, Voichita D. Marinescu, Brian Chow, Alexander D Wissner-Gross and Peter Carr
Promoter (lacI regulated, lambda pL hybrid)
represillator of Elowitz and Leibler (2000)
Inverting regulatory region controlled by LacI (<bb_part>BBa_C0010</bb_part>, <bb_part>BBa_C0011</bb_part>, 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 tightly repressed by LacI, the Lac inhibitor (i.e. repressor) (<bb_part>BBa_C0010</bb_part>) ([LUTZ97]). The activity of the promoter can be regulated over a >600-fold range by IPTG in E.Coli DH5-alpha-Z1 (same paper reference).
hybrid promoter design to create strong promoter that is, at the same time, highly repressible. note that the upstream operator installed in this hybrid is slightly different than the one in the original source (Lutz and Bujard, 1997). the most upstream operator region is slightly truncated in the represillator version, so that both operators in the hybrid are the same sequence. see references for details. also, the sequence has been truncated after the transcriptional start site. LacI binds to this regulator. This part is incompatible with species containing active LacI coding regions. Lactose and IPTG disable the operation of LacI and increase transcription. This part is incompatible with environments containing lactose or lactose analogs.
Neelaksh Varshney, Grace Kenney, Daniel Shen, Samantha Sutton
This device accepts PoPS as input and produces the LuxI enzyme. This enzyme produces 3OC6HSL.
position 3 mutated promoter lux pR-3 (luxR & HSL regulated)
The position 3 mutated promoter lux pR-3 is based on promoter lux pR (BBa_R0062).
The position 3 mutated promoter lux pR-3 is a product of site-directed mutagenesis of promoter lux pR (BBa_R0062). The promoter lux pR is based on the Vibrio fischeri quorum sensing gene promoters. The position 3 mutated promoter lux pR-3 gives a higher expression of downstream genes in an autoinduction system. In another word, the lux pR-3 has a higher efficiency than the lux pR. Similar to promoter lux pR, the expression is up-regulated by the action of LuxR protein combined with the signal molecule HSL.
In the promoter lux pR's sequence, the C residue of position 3 was changed to a T using PCR method.
Double terminator consisting of BBa_B0010 and BBa_B0012
PCR from the plasmid pluxCcdB3(a gift from Prof. Lingchong You). Forward Primer: GTTTCT TCTAG ATG accatgattacgg attcactggccgtcgttttac Reverse Primer: GTTTCTTC CTGCAG CGGCCGC T ACTAGT A TTATTA tattccccagaacatcaggtta Digest with XbaI and SpeI, ligate into pSB1A3.
A fusion protein of lacZalpha(I732006) and ccdB(K145151). It should have the function of ccdB to cause E. coli cells to die, but have less toxicity because of the lacZalpha part. It should also have the function of lacZalpha as a reporter for measurement. This part is similar to J32026 but the multiple cloning sites are eliminated. It is constructed by PCR from the plasmid pluxCcdB3(a gift from Prof. Lingchong You).
The part is similar to BBa_J32026 and the original coding sequence in pluxCcdB3, but the multiple cloning sites are eliminated in order to avoid site-specific mutagenesis. The multiple cloning sites are from lacZalpha in pZErO-2. After eliminate the MCS, the lacZalpha part is identical to the N-terminal of the wild type gene(BBa_I732006 & BBa_I732005), and fused with the ccdB part (BBa_K145151) with a 3aa linker.
Synthesizes 3OC6HSL, which binds to LuxR. The lux cassette of V. fischeri contains a left and a right promoter. The right promoter gives weak constitutive expression of downstream genes.This expression is up-regulated by the action of the Lux repressor, LuxR. Two molecules of LuxR protein form a complex with two molecules the signalling compound HSL. This complex binds to a palindromic site on the promoter, increasing the rate of transcription.
An LVA tail (sequence: AANDENYALVA) was added to increase protein degradation. .
Conversion of the iGEM parts registry to SBOL2.1