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Bacterial Signal Peptide Vector Set

plasmid vectors for molecular cloning

cloning vector, expression vector, molecular cloning vector, plasmid, plasmid vector, snapfast vector, vector


6-His tagged


buffered aqueous solution

bacteria selection


Origin of replication

pUC (500 copies)

Peptide cleavage

no cleavage

Peptide tag location



Promoter name: OXB20
Promoter activity: constitutive
Promoter type: bacterial

Secretion signal


shipped in


storage temp.


General description

Molecular cloning often benefits from optimizing the vector used for expression.

This pack allows you to compare the activity of eleven different bacterial secretory tags (signal peptides) to identify which is most efficient for the secretion of your protein of interest. This can be very important in influencing yields in bacterial cultures. The most efficient tag seems to depend on the protein of interest and also on the cells used, hence we consider it important to compare several tags in order to select the best. Inserting your gene of interest into the MCS of these plasmids will place it downstream of the signal peptide, under regulatory control of the strong constitutive OXB20 bacterial promoter.This plasmid set has been designed to be compatible with a range of cloning techniques. The multiple cloning site contains a range of standard commonly used restriction sites for cloning. Using these sites genes can be inserted using standard cloning methods with DNA ligase. Other methods such as ligase independent cloning (LIC) Gibson Assembly InFusionHD or Seamless GeneArt can also be used and because all of our plasmids are based on the same backbone the same method can be used for cloning into all of our catalogue vectors.

Multiple cloning site notes: There are a few important sites within the MCS. These include the NcoI site the XbaI site and the BsgI and BseRI sites. The NcoI site contains a start codon that is immediately downstream of both a Kozak and Shine-Dalgarno ribosomal binding site. These allow for optimal positioning of genes when the start codon is placed in this location. If this is not required and you wish to use a downstream site for gene cloning you can remove the NcoI site by cleaving the plasmid with KpnI. The XbaI site contains a stop codon. This stop codon is positioned in a specific position in relation to the BsgI and BseRI sites that are immediately downstream. When either BseRI or BsgI cleave the plasmid they produce a TA overhang from the stop codon in the XbaI site that is compatible with all of our peptide tag plasmids cut with the same sites. BseRI and BsgI sites are non-palindromic and cleave a defined number of bases away from their binding site. Whenever we clone a gene into our multiple cloning site we always position the start and stop codon in the same positions in the MCS. If the start and ends of the genes are not compatible with NcoI and XbaI we extend the sequence to the nearest external sites but keep the start and stop codons locations consistent.

Transcription Termination: These plasmids 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.


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Analysis Note

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Legal Information

These plasmids are sold free of reach-through rights and can be used to make commercial products. However the plasmids themselves (or derivatives) cannot be sold.

Kit Components Only

Product No.

  • PSF-OXB20-NH2-GIII - GIII SECRETION PLASMID, plasmid vector for molecular cloning

Kit Components Also Available Separately

Product No.

  • OGS3042PSF-OXB20-NH2-OMPA-6HIS-TEV - OMPA SECRETION AND 6 HIS TAG PLASMID, plasmid vector for molecular cloningSDS

  • OGS3157PSF-OXB20-NH2-PELB - PELB SECRETION PLASMID, plasmid vector for molecular cloningSDS

  • OGS3158PSF-OXB20-NH2-DSBA - DSBA SECRETION PLASMID, plasmid vector for molecular cloningSDS

  • OGS3160PSF-OXB20-NH2-OMPC - OMPC SECRETION PLASMID, plasmid vector for molecular cloningSDS

  • OGS3161PSF-OXB20-NH2-OMPT - OMPT SECRETION PLASMID, plasmid vector for molecular cloningSDS

  • OGS3162PSF-OXB20-NH2-PHOA - PHOA SECRETION PLASMID, plasmid vector for molecular cloningSDS

  • OGS3163PSF-OXB20-NH2-SUFI - SUFI SECRETION PLASMID, plasmid vector for molecular cloningSDS

  • OGS3164PSF-OXB20-NH2-TORA - TORA SECRETION PLASMID, plasmid vector for molecular cloningSDS

  • OGS3165PSF-OXB20-NH2-TORT - TORT SECRETION PLASMID, plasmid vector for molecular cloningSDS

  • OGS3166PSF-OXB20-NH2-MALE - MALE SECRETION PLASMID, plasmid vector for molecular cloningSDS

See All (10)

Storage Class Code

12 - Non Combustible Liquids

Flash Point(C)

Not applicable

Certificate of Analysis

Enter Lot Number to search for Certificate of Analysis (COA).

Certificate of Origin

Enter Lot Number to search for Certificate of Origin (COO).

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