CGSC Strain#: 12504
Strain Designation: BL21(DE3)     
Source of Strain: Sex: F-
Chromosomal Markers: lon-11,
Δ(ompT-nfrA)885,
Δ(galM-ybhJ)884,
λDE3 [lacI, lacUV5-T7 gene 1, ind1, sam7, nin5],
Δ46,
[mal+]K-12(λ
S)
,
hsdS10Strain Comments: - lon-11-- is a mutation of an E. coli B gene caused by an IS186 insertion in the promoter. All derivatives of Witkin's B wildtype carry this lon mutation.
- Δ(ompT-nfrA)885-- This deletions actually spans from distal region of the DLP12 prophage to an Rhs element just downstream of nfrA in the E. coli B genome. Actual genes deleted are appY, ompT, envY, ybcH, and nfrA.
- Δ(galM-ybhJ)884-- Deletion from base 769,048 to 786,294 in the REL606 genome and includes the following genes: galMKTE, modFE, acrZ, modABC, ybhA, pgl, ybhD, ybhH, ybhI, and ybhJ
- λDE3 [lacI, lacUV5-T7 gene 1, ind1, sam7, nin5]-- Lambda DE3 has the phage T7 RNA polymerase under the control of the lacUV5 promoter inserted into the BamHI site of the Lambda cloning vector D69.
- Δ46-- : cured of defective P2-like prophage found in wildtype E.coli B.
- [mal+]K-12(λS)-- The malK, lamB, malM region was transduced in from E. coli K-12.
- Δ(galM-ybhJ)884 was formerly called
- LamS = Lambda sensitive
References: - Wood, W.B. 1966. Host specificity of DNA produced by Escherichia coli: bacterial mutations affecting the restriction and modification of DNA. J.Mol.Biol. 16:118-133