Ultra competent cells of DH5a and DB3.1 prepared and stored at -80 degrees Celsius.
OD for Dh5a was 0.4 and 0.9 for DB3.1 (protocol states that it should be about 0.3 to 0.5); LB was used as blank whereas media used for inoculation of cells was SOB.
Transformation of DB3.1 with the following 5 Plasmid backbones :