Common E. coli Strains

E.coli Strain Genotypes

Commonly Used Escherichia coli Strains

Straina Genotype
AR58 sup0 galK2 galE::Tn10 (λcI857 ΔH1 bio- uvrB kil- cIII-) Strr
AR120 sup0 galK2 nad::Tn10 (Tetr) (λcI+ ind+ PL-lacZfusion) Strr
ASIb endA1 thi-1 hsdR17(rK-mK+) supE44cI+)
BNN102b C600 hflA150 chr::Tn10 mcrA1 mcrB
BW313c Hfr lysA- dut ung thi-1 recA spoT1
C600 thi-1 thr-1 leuB6 lacY1 tonA21 supE44 mcrA
CJ236c dut1 ung1 thi-1 relA1/pCJ105 (Cmr)
DH1 recA1 endA1 thi-1 hsdR17 supE44 gyrA96 (Na1r) relA1
DH5alpha F'd F'/endA1 hsdR17(rK-mK+) supE44 thi-1 recA1 gyrA (Na1r) relA1 Δ(lacZYA-argF)U169(m80lacZΔM15)
DK1 hsdR2 hsdM+ hsdS+ araD139 Δ(ara-leu)7697Δ(lac)X74 galU galK rpsL (Strr) mcrA mcrB1 Δ(srl-recA)306
ER1451 F' traD36 proAB laclq Δ(lacZ)M15/endA gyrA96 thi-1 hsdR2 (or hsdR17) supE44 Δ(lac-proAB) mcrB1 mcrA
HB101e Δ(gpt-proA)62 leuB6 thi-1 lacY1 hsdSB20 recA rpsL20 (Strr) ara-14 galK2 xyl-5 mtl-1 supE44 mcrBB
JM101f F' traD36 proA+ proB+ laclq lacZΔM15/supE thi Δ(lac-proAB)
JM105f F' traD36 proA+ proB+ laclq lacZΔM15/Δ(lac-pro)X111 thi rpsL (Strr) endA sbcB supE hsdR
JM107f F' traD36 proA+ proB+ laclq lacZΔM15/endA1 gyrA96 (Nalr) thi hsdR17 supE44 relA1 Δ(lac-proAB) mcrA
JM109g F' traD36 proA+ proB+ laclq lacZΔM15/recA1 endA1 gyrA96 (Nalr) thi hsdR17 supE44 relA1 Δ(lac-proAB) mcrA
K38 HfrC (λ)
KM392 hsdR514(rK-mK+) supE44 supF58lacY galK2 galT22 metB1 trp55 mcrA ΔlacU169 proC::Tn5
LE392 hsdR514(rK-mK+) supE44 supF58lacY galK2 galT22 metB1 trp55 mcrA
MC1061 hsdR2 hsdM+ hsdS+ araD139 Δ(ara-leu)7697D(lac)X74 galE15 galK16 rpsL (Strr) mcrA mcrB1
MM294 endA thiA hsdR17 supE44
NM539h supF hsdR (P2cox3)
P2392 hsdR514 (rK-mK+ ) supE44 supF58 lacY galK2 galT22 metB trp55 mcrA (P2)
PR722 F' Δ(lacIZ)E65 pro+/proC::Tn5 Δ(lacIZYA)U169 hsdS20 ara-14 galK2 rpsL20 (Strr) xyl-5 mtl-1 supE44 leu
Q359 hsdR- hsdM+ supE tonA (φ80r) (P2)
RR1 Δ(gpt-proA)62 leuB6 thi-1 lacY1 hsdSB20 rpsL20 (Strr) ara-14 galK2 xyl-5 mtl-1 supE44 mcrBB
Y1088h supE supF metB trpR hsdR- hsdM+ tonA21 strA ΔlacU169 mcrA proC::Tn5/pMC9
Y1089h ΔlacU169 proA+ Δ(lon) araD139 strA hflA150 chr::Tn10/pMC9
Y1090h ΔlacU169 proA+ Δ(lon) araD139 strA supF trpC22::Tn10 mcrA/pMC9

a The original E. coli K-12 strain was an F + λ lysogen, but most K-12 derivatives in common use have been cured of the F factor and prophage and these are indicated only when present. All other genes in these strains are presumed to be wild-type except for the genotype markers noted in the second column.

b AS1 is also known as MM294cI +, BNN102 is also known as C600 hflA.

c Both CJ236 and BW313 are commonly used in oligonucleotide-directed mutagenesis, pCJ105, the plasmid CJ236 carries, is not relevant for this application.

d Three strains are in circulation. DH5 is a derivative of DH1 that transforms at higher efficiency. DH5α and DH5αF’ are derivatives that carry a deletion of the lac operon and φ80 prophage that directs synthesis of the omega fragment of β-galactosidase. DH5αF’ carries an F’ factor as well. DH5α and DH5αF’ are proprietary strains and the cells are prepared in some way that allows them to be transformed with slightly higher efficiency than DH5.

e In this strain, the area of the chromosome that contains the hsd genes was derived from the related B-strain of E. coli.

f The continued presence of the F’ factor in JM strains can be insured by starting cultures only from single colonies grown on minimal plates that do not contain proline. These strains encode the omega fragment of lacZ and are frequently used with vectors that direct the synthesis of the lacZ alpha fragment. These strains are frequently used with M13 vectors for DNA sequencing.

g It is not known whether this strain has markers other than those listed.
h pMC9, the plasmid in the Y strains listed here, directs the synthesis of large amounts of lac repressor It also confers resistance to tetracycline and ampicillin (Miller et al., 1984, EMBO.J.3:3117-3121).

Adapted from Current Protocols in Molecular Biology, Ausubel, Brent, Kingston, Moore, Seidman, Smith, and Struhl eds.