Product Name: pSF-OXB20-BetaGal_(previously_(pSF-RecA-BetaGal)
Product Code: OG207
Size (bp): 6969 bp
Bacterial Antibiotic Selection: KanR
Origin and Compatibility: pUC high copy derived from pBR322
Bacterial Copy Number: 500-700 per cell
Promoter: OXB20 strong constitutive bacterial promoter
The expression of the beta galactosidase (beta gal) reporter gene under the control of the RecA constitutive bacterial promoter. This plasmid can be used for monitoring reporter gene activity in bacterial cells or colonies using X-Gal which will produce a blue colouration. The reporter gene has been inserted thin the primary multiple cloning site. X-Gal is not membrane permeable and so cells must be lysed prior to detect when screening for blue colonies on an agar plate sufficient cells will naturally lyse on the plate to allow blue colony detection.Promoter Expression Level:
This plasmid contains a constitutive bacterial promoter that does not require induction. It is the strongest bacterial promoter we sell and this can cause solubility and expression problems with some proteins. We also offer a range of other bacterial promoters that are compatible with this plasmid and are available on request.
This plasmid contains three alternative transcription terminators for mammalian bacterial and bacteriophage (T7) expression. This means that only the promoter needs to be changed to alter the expression system you are using. We sell multiple promoters that can be used in each of these systems. The presence of each terminator does not reduce expression in the alternative systems.
This plasmid contains a gene within the main multiple cloning site (NotI-ClaI). Any plasmid that we sell where the gene is this configuration will be located in the exact same position in relation to the start and stop codon of the gene. The only exceptions to this rule are fusions proteins where the fusion gene may be positioned at the front or end of the MCS to allow gene fusion.
By positioning all of our genes in the same location it allows them to be transferred between plasmids using the same cloning method and restriction sites regardless of the plasmid being used from our product range. Inserting a new gene into this plasmid should be easily possible using a range of standard restriction enzyme sites that flank the gene currently in the vector.Multiple cloning site notes:
In the multiple cloning site there are two important restriction sites called BsgI and BseRI sites. These sites both cut the DNA at the same position and cleave the stop codon of the gene in the multiple cloning site in this plasmid thereby producing a TA overhang. This overhang is compatible with any of our peptide or reporter fusion tag plasmids also cut with either of these enzymes. This allows seamless C-terminal fusions to be made with the gene in this multiple cloning site using a single cloning step from our C-terminal peptide and reporter tag product range. Normally the easiest method is to clone the C-terminal tag from our other plasmid products into this plasmid using BsgI or BseRI and the downstream ClaI restriction site.
BseRI and BsgI sites are non-palindromic and cleave a defined number of bases away from their binding sites. This allows them to cut the upstream stop codon in the gene in this plasmid regardless of the gene sequence.