Fig. 6.
In vitro methylation by M.EcoRI allows for transformation of plasmid DNA. (A) Plasmid map of pJMB202 with pertinent features denoted. KanR refers to a kanamycin resistance cassette. It is inserted in astA. Red lines indicate EcoRI sites (GAATTC) that are methylated by M.EcoRI. Green lines indicate CtsM sites (RAATTY) that cannot be methylated by M.EcoRI. (B) WT cells were transformed with various types of DNA as indicated. These DNA fragments were then used to transform WT cells. Transformation efficiency was calculated as described previously. The data represent three biological replicates, each of which contained three technical replicates. n.d. indicates that colonies were not detected. Error bars indicate SD. *P < 0.001; **P < 0.001, one-way ANOVA with Tukey’s posttest. ns, not significant.