|Genotype||gyrA462 endA1 ∆(sr1-recA) mcrB mrr hsdS20 glnV44 (=supE44) ara14 galK2 lacY1 proA2 rpsL20 xyl5 leuB6 mtl1|
|Phenotype||Streptomycin resistant, ccdB resistant|
DB3.1 is a HB101 derivative containing the gyrA462 allele which renders the strain resistant to the toxic effects of the ccdB gene.
Original Invitrogen catalogue number: 11782-018. However, this strain is no longer available at Invitrogen.
Alternative: ccdB-resistant One Shot® ccdB Survival™ 2 T1R Competent Cells, of which the ccdB-resistance mechanism is not known; it is based on empirical results and the success or failure of the transformation of the cells is plasmid-dependent.