Figure 4. Seven inner bases of DUS are critical for enhancement of transformation.

Competence for DNA transformation in N. meningitidis 8013 was quantified after transformation with 100 ng of ΔpilN PCR fragments containing a series of DUS mutants in which each base of the DUS was mutated. The specific transversion mutations are indicated in each case. As a control, the WT strain transformed with DUS and no DUS was included. Results are expressed as percentages of recipient cells transformed, and are the mean ± standard deviation of six independent experiments.