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  • E. coli K12 ER1793

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    Catalog #SizeConcentrationPriceQtyAdd to Cart
    E4101S200 μl$0.00Add to Cart
    Strain Products


    A suspension of E. coli ER1793 which has been grown in rich medium and brought to 50% glycerol. ER1370 background; McrA- McrBC- Mrr- EcoK r- m-


    F- fhuA2 Δ(lacZ)r1 glnV44 e14-(McrA-) trp-31 his-1 rpsL104 xyl-7 mtl-2 metB1 Δ(mcrC-mrr)114::IS10

    Properties and Usage

    Storage Temperature


    Antibiotic Resistance

    • str

    Growth Media


    Growth Temperature

    37 °C


    1. Restriction Defects: McrA, McrBC, and Mrr all restrict methylcytosine-containing DNA methylated by the CpG methylase (M.Sss I) (1). In addition, McrA and McrBC specifically restrict DNA modified by different sets of more sequence-specific cytosine methylases (2).
    2. Mrr also restricts many methyladenine-containing sequences (3,4). Restriction by each of these three restriction systems individually (tested with λ DNA modified with the Sss I methylase and then packaged into phage) is: McrA, 250-fold; McrBC, 100-fold; Mrr, 200-fold. Cumulative restriction when all three are present in the same cell is 5,000-fold (1). In addition, EcoK restricts DNA not modified at K sites by 10-fold to 5,000-fold, depending on the number of sites (5). ER1793 is deficient in all four systems (1). This strain was reported to yield good quality libraries of Helicobacter pylori chromosomal DNA (6).


    1. Kelleher, J.E. and Raleigh, E.A. (1991). J. Bacteriol.. 173, 5220-5223.
    2. Raleigh, E.A. and Wilson, G. (1986). Proc. Natl. Acad. Sci. USA. 83, 9070-9074.
    3. Waite-Rees, P.A. et al. (1991). J. Bacteriol.. 173, 5207-5219.
    4. Heitman, J. and Model, P. (1987). J. Bacteriol.. 169, 3243-3250.
    5. Murray, N.E. et al. (1973). Mol. Gen. Genet.. 120, 261-281.
    6. Phadnis, S.H. et al. (1993). Mol. Microbiol.. 10, 1151.

    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.