Transformation of a toxic mammalian clone into E. coli hosts A T7 expression plasmid and the same plasmid containing a gene encoding a toxic mammalian protein were transformed into each host. Comparison of the relative transformation efficiencies demonstrates that the T7 Express hosts provide the levels of control necessary for transformation of potentially toxic clones. BL21(DE3) could not be transformed with the toxic clone.T7-controlled expression of a non-toxic protein in E. coli hosts A T7 expression plasmid containing a gene encoding an E. coli protein was transformed into each host, grown to 0.6 OD and induced for 3 hours. Comparison of soluble extracts from uninduced (-) and induced (+) cells shows superior control of basal expression in the T7 Express hosts while maintaining high levels of induced expression. Effect of heat shock time on T7 Express competent E. coli transformation efficiency50 μl of competent cells were transformed with 100 pg of pUC19 control DNA following the provided High Efficiency Transformation Protocol except heat shock time varied from 0 to 80 seconds..Effect of DNA incubation time on T7 Express competent E. coli transformation efficiency 50 μl of competent cells were transformed with 100 pg of pUC19 control DNA following the provided High Efficiency Transformation Protocol except DNA incubation time varied from 0 to 40 minutes.
CAUTION: This product contains DMSO, a hazardous material. Review the MSDS before handling.
STORAGE AND HANDLING: Competent cells should be stored at -80°C. Storage at -20°C will result in a significant decrease in transformation efficiency. Cells lose efficiency whenever they are warmed above -80°C, even if they do not thaw.
Anton, B.P., Fomenkov, A., Raleigh, E.A. and Berkmen, M. (2016) Complete Genome Sequence of the Engineered Escherichia coli SHuffle Strains and Their Wild-Type Parents Genome Announc; Mar 31;4(2), PubMedID: 27034504, DOI: 10.1128/genomeA.00230-16.
Publications
Anton, B.P., Fomenkov, A., Raleigh, E.A. and Berkmen, M. (2016) Complete Genome Sequence of the Engineered Escherichia coli SHuffle Strains and Their Wild-Type Parents Genome Announc; Mar 31;4(2), PubMedID: 27034504, DOI: 10.1128/genomeA.00230-16.
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