TABLE 3.
Strain | Relevant genotype | Amt (pg) of DNA/5 × 108 cells (n)b
|
|
---|---|---|---|
Bound | Taken up | ||
LO15 | Wild type | 144 ± 42 (11) | 55 ± 20 (10) |
Tf59 | pilT | 210 ± 36 (3) | 20 ± 2 (3)c |
Tf591 | pilU | 135 ± 26 (4) | 36 ± 10 (4) |
Tf700 | pilT pilU | 228 ± 59 (5) | 14 ± 9 (4)c |
Tf591(pKTpilU)d | pilU/pilU+Pa | 119 ± 33 (6) | 43 ± 13 (6) |
The cells were from the late logarithmic growth phase, in which LO15 cells (wild type) are at the competence maximum (0.5 × 109 to 1 × 109 cells per ml).
n, number of experiments. Data are averages with standard deviations.
The DNA uptake by Tf59 and Tf700 was found by t test to be significantly lower than that of LO15 (P = 0.015 and 0.002, respectively).
The plasmid pKTpilU expresses the pilU+ gene of P. aeruginosa (Pa) (42).