FIG 1.

Plasmid stability of the TnKRM and TnFLX series. Restriction digests of individually isolated plasmids from colonies isolated from a clonal E. coli culture grown overnight at 37°C in LB amp were resolved on a 1% agarose gel. (A) pTnKRM kan (pKB178) was digested with NheI and EcoRI. Fragment sizes of approximately 3,900, 2,850, and 1,450 bp are expected. (B) pTnFLX kan (pFK131) was digested with EcoRV. Fragments sizes of approximately 7,650, 1,050, 750, and 200 bp are expected. A 1-kb DNA ladder (New England Biolabs) was provided for size determination, with marker sizes indicated in kbp. Arrowheads indicate expected fragment sizes.