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(Plasmid #89880)


Item Catalog # Description Quantity Price (USD)
Plasmid 89880 Standard format: Plasmid sent in bacteria as agar stab 1 $85

This material is available to academics and nonprofits only.


  • Vector backbone
  • Backbone manufacturer
  • Backbone size w/o insert (bp) 5400
  • Total vector size (bp) 5802
  • Vector type
    Bacterial Expression

Growth in Bacteria

  • Bacterial Resistance(s)
    Ampicillin, 100 μg/mL
  • Growth Temperature
  • Growth Strain(s)
  • Growth instructions
    DH5alpha for propagation of the plasmid. Bl21[DE3] or similar required for protein expression.
  • Copy number
    Low Copy


  • Gene/Insert name
  • Alt name
  • Species
    E. coli
  • Insert Size (bp)
  • Mutation
  • Tag / Fusion Protein
    • 6 glutamate tag (C terminal on insert)

Cloning Information

Terms and Licenses

  • Academic/Nonprofit Terms
  • Industry Terms
    • Not Available to Industry
  • Zeocin® is an InvivoGen trademark.

Depositor Comments

The residue numbering is based 1986 paper from Charles Cantor: (see Figure 3)
In the original sequence, there is a signal peptide and N-terminal sequence that are proteolytically processed. Thus, the most common version is Core Streptavidin, which starts at residue 13 and ends at residue 139, as shown here: (see Figure 1)

How to cite this plasmid ( Back to top)

These plasmids were created by your colleagues. Please acknowledge the Principal Investigator, cite the article in which the plasmids were described, and include Addgene in the Materials and Methods of your future publications.

  • For your Materials & Methods section:

    pET21-Streptavidin-K121R was a gift from Mark Howarth (Addgene plasmid # 89880 ; ; RRID:Addgene_89880)
  • For your References section:

    Amine Landscaping to Maximize Protein-Dye Fluorescence and Ultrastable Protein-Ligand Interaction. Jacobsen MT, Fairhead M, Fogelstrand P, Howarth M. Cell Chem Biol. 2017 Jul 17. pii: S2451-9456(17)30229-5. doi: 10.1016/j.chembiol.2017.06.015. 10.1016/j.chembiol.2017.06.015 PubMed 28757182