QIAprep Spin Miniprep Kit was used to purify DNA from 1.5 ml LB overnight cultures of DH5a containing pUC19, or pVMG or pVO155. Elution was performed according to the standard protocol (50 μl Buffer EB and 1 min incubation). Use of the recommended LB composition (with 10 g/liter NaCl) and Nm resistance provides optimal plasmid yield. Time spent was < 15 min. Costs per μg DNA was 7 cents.