TABLE 3.
Segregation patterns of coresident pRAS3 plasmids and derivatives in an E. coli host
| pRAS3 plasmid | Coresident plasmida |
% colonies with resistance to the following antibiotic(s)b: |
Direction and strength of segregation biasc | ||||
|---|---|---|---|---|---|---|---|
| pRAS3.2.Km | pRAS3.1.35.Km | pRAS3.1.Km | Tet only | Km only | Tet and Km | ||
| pRAS3.2 | • | 0 ± 0 | 98 ± 3 | 2 ± 3 | 3 iterons and 4 6-bp repeats <<< 4 iterons and 5 6-bp repeats | ||
| pRAS3.1 | • | 98 ± 0 | 0 ± 0 | 2 ± 0 | 4 iterons and 5 6-bp repeats >>> 3 iterons and 4 6-bp repeats | ||
| • | 79 ± 4 | 0 ± 0 | 21 ± 4 | 4 iterons >>> 3 iterons | |||
| • | 23 ± 7 | 20 ± 8 | 57 ± 11 | Tet ≈ Km | |||
| pRAS3.1.35 | • | 0 ± 0 | 87 ± 10 | 12 ± 8 | 3 iterons <<< 4 iterons | ||
| • | 24 ± 3 | 13 ± 1 | 62 ± 3 | Tet > Km | |||
| pRAS3.1.34 | • | 14 ± 0 | 18 ± 14 | 66 ± 14 | 4 6-bp repeats ≈ 5 6-bp repeats | ||
| pRAS3.1.44 | • | 30 ± 6 | 8 ± 6 | 60 ± 17 | 4 6-bp repeats > 5 6-bp repeats | ||
a
The small black circles indicate the plasmid in the cell in addition to the pRAS3 plasmid used in each experiment. Each plasmid was completely stable on its own for the duration of the assay in the absence of antibiotic.
b
Tet, tetracycline; Km, kanamycin.
c
Direction and strength of segregation bias as a result of iteron and/or 6-bp repeat copy number, as well as the influence of the antibiotic resistance genes. Arrowheads indicate the direction of plasmid displacement, and the number of arrowheads is an indication of the strength of displacement. Tet, tetracycline resistance gene; Km, kanamycin resistance gene.