Figure 3From: Optimization of an E. coli L-rhamnose-inducible expression vector: test of various genetic module combinationsComparison of plasmid-DNA amounts in the E. coli strain JM109. Cells were grown at 37°C in LB with ampicillin for 16 h, plasmid DNA was isolated by a boiling preparation [37] and the supernatants were analyzed by electrophoresis on a 0.5% agarose-gel and visualized by EtBr staining. Lanes 1 and 11: 1 Kb DNA Ladder (Invitrogen).Back to article page