Tetracycline/aTc inducible promoter with GFP reporter tagged with NYADAS-ssrA degradation tag followed by terminator. The tagged GFP is actively degraded within cell, thus provides better temporal resolution of green fluorescence and promoter activity.
Part was assembled using BrickClip assembly (BBF RFC104) using other biobrick parts as templates. BrickClip assembly is a special case of more general Paperclip assembly method.[1]
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.
Lutz, R., Bujard, H., Nucleic Acids Research (1997) 25, 1203-1210.
Sequence for pTet inverting regulator driven by the TetR protein.
BBa_R0040 TetR-Regulated Promoter is based on a cI promoter. It has been modified to include two TetR binding sites and the BioBrick standard assembly head and tail restriction sites.
June Rhee, Connie Tao, Ty Thomson, Louis Waldman
Double terminator consisting of BBa_B0010 and BBa_B0012
GFP (mut3b) with SsrA-DAS+2 degradation tag
GFP comes from part BBa_E0040, the tag sequence was obtained from part BBa_M0051.
GFP (mut3b) (see part BBa_E0040) with added engineered NYADAS-ssrA degradation tag (see part BBa_M0050). The tag increases GFP turn-over rate, thus providing better temporal resolution of green fluorescence. In the same time, maximal fluorescence amplitudes will be lower as newly formed protein is degraded as soon as it is formed. SsrA tags encode peptide sequence that and is recognized by ClpA and ClpX unfoldases and ClpX mediator SspB.[1] ClpA and ClpX then form a proteosome-like complex with ClpP protease and the protein is degraded.[1] The final three residues of the tag determines the strength of interaction with ClpX and thus the final protein degradation rate.[2] The NYADAS tag encodes peptide sequence AANDENYNYDAS is reported to have low affinity to ClpX thus its mediated degradation very much depends on the concentration of SspB (ClpX mediator).[1] The two additional residues ???NY??? extends tag between SspB and ClpX binding site, thus preventing clash when both these protein are bound to tag.[3] However, be aware that exact protein degradation rate is influenced by multiple other factors: ClpXP and ClpAP protease concentrations, protein stability, Km of binding to the protease, temperature [4]. ===References=== [1] Flynn, J. M. et al. Overlapping recognition determinants within the ssrA degradation tag allow modulation of proteolysis. Proc. Natl. Acad. Sci. U. S. A. 98, 10584???9 (2001). [2] Andersen, J. B. et al. New unstable variants of green fluorescent protein for studies of transient gene expression in bacteria. Appl. Environ. Microbiol. 64, 2240???6 (1998). [3] McGinness, K. E., Baker, T. a & Sauer, R. T. Engineering controllable protein degradation. Mol. Cell 22, 701???7 (2006). [4] Purcell, O., Grierson, C. S., Bernardo, M. Di & Savery, N. J. Temperature dependence of ssrA-tag mediated protein degradation. J. Biol. Eng. 6, 10 (2012).
The tag was attached to GFP using PCR and MABEL (mutagenesis with blunt-end ligation), thus avoiding introduction of additional residues and restriction site. Different parts of the tag are recognized by different proteins, for example, the final 3 residues (DAS in this case) are recognized by ClpX, whereas first 4 residues of the tag are required for efficient SspB binding.[1] Thus modifications of these critical residues alter the efficacy with what different proteases bind to it.
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.
Conversion of the iGEM parts registry to SBOL2.1