E. coli were grown under antibiotic selection to maintain expression vectors for GST-6xHis, GST-6xHis-melittin, or no expression vector control and were grown in the presence and absence of 0.1 mM IPTG. Doubling times were found to be dependent upon the plasmid and IPTG treatment (2-way ANOVA, p-value < 0.05 for the interaction, [IPTG], and plasmid). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)