TABLE 5.
HPK1 (Specr Rifr) | HPK5 (Strepr pHP1 Kanr) | Treatment with DNase I (285 μg/ml) | Specr/Strepr CFU/107 bacterial pairsa | Relative %b |
---|---|---|---|---|
Cellsc | —e | − | 0 | 0 |
Supernatantd | — | − | 0 | 0 |
— | Cells | − | 0 | 0 |
— | Supernatant | − | 0 | 0 |
Cells | Cells | − | 112 ± 22 | 100 |
Cells | Cells | + | 12 ± 5 | 11f |
Supernatant | Cells | − | 67 ± 24 | 60g |
Supernatant | Cells | + | 0 | 0 |
Cells | Supernatant | − | 10 ± 2 | 9f |
Cells | Supernatant | + | 0 | 0 |
Mean ± SEM of three replicate experiments.
In comparison to cell-cell mating in the absence of DNase I.
H. pylori cells from 48-h cultures on two TSA plates were resuspended in 250 μl of 0.9% saline, and 25 μl of the suspension was used as the source of cells.
H. pylori cells from 48-h cultures on two TSA plates were suspended in 1 ml of 0.9% saline. The suspension was centrifuged at 8,500 × g for 5 min. The supernatant was saved and either passed through a 0.2-μm-pore-size filter or treated with 5% CHCl3.
—, no exogenous DNA source.
P < 0.01 compared to cell-cell mating in the absence of DNase (Mann-Whitney test).
P > 0.05 compared to cell-cell mating in the absence of DNase (Mann-Whitney test).