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  • pBR322 Vector


    pBR322 DNA is a commonly used plasmid cloning vector in E. coli (1). The molecule is a double-stranded circle 4,361* base pairs in length (2). pBR322 contains the genes for resistance to ampicillin and tetracycline, and can be amplified with chloramphenicol. The molecular weight is 2.83 x 106 daltons.

    *Sequencing data from Watson (confirmed at New England Biolabs, Inc.) has shown pBR322 to be 4,361 base pairs, not 4,363 base pairs as previously reported.

    DNASU is a central repository for plasmid clones and collections that may also be helpful.

    Product Source

    pBR322 is isolated from E. coli ER2272 (dam +dcm + EcoK M-) by a standard plasmid purification procedure.


    Properties and Usage

    Copy Number

    Medium (10-100)

    Origin of Replication

    • pMB1

    Storage Temperature


    Storage Conditions

    10 mM Tris-HCl
    1 mM EDTA
    pH 8.0 @ 25°C


    1. Bolivar, F., Rodriguez, R.L., Greene, P.J., Betlach, M.C., Heynecker, H.L. and Boyer, H.W. (1977). Gene. 2, 95-113.
    2. Watson, N. (1988). Gene. 70, 399-403.

    Supporting Documents

    Material Safety Datasheets

    The following is a list of Material Safety Data Sheets (MSDS) that apply to this product to help you use it safely. The following file naming structure is used to name these document files: [Product Name] MSDS. For international versions please contact us at info@neb.com.


    The Product Summary Sheet, or Data Card, includes details for how to use the product, as well as details of its formulation and quality controls. The following file naming structure is used to name the majority of these document files: [Catalog Number]Datasheet-Lot[Lot Number]. For those product lots not listed below, please contact NEB at info@neb.com or fill out the Technical Support Form for appropriate document.
    1. How homogeneous is the DNA/ how much is supercoiled?
    2. Are the plasmids cesium purified?

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