Table 6.
The contribution of the Salmonella spvB-virulence plasmid on exclusion of IncF plasmids in natural S. enterica isolates.
| Plasmid | Recipient staina | Plasmid transfer frequencyb | P-valuec | |
|---|---|---|---|---|
| Average | ±SEM | |||
| FI (pOX38-km) | S. Typhimurium LT2 pSLT+ | 2.69 × 10−3 | ±1.49 × 10−3 | 0.042 |
| S. Typhimurium LT2 pSLT− | 3.14 × 10−2 | ±1.13 × 10−2 | ||
| S. Typhimurium 98A-28238R (spvB-virulence plasmid−) | 3.42 × 10−5 | ±0.55 × 10−5 | ||
| S. Typhimurium 98A-33516R (spvB-virulence plasmid+, pSLT traS−) | 9.25 × 10−6 | ±1.21 × 10−6 | 0.034, 0.006d | |
| S. Dublin 564R (spvB-virulence plasmid+, pSLT traS−) | 1.22 × 10−4 | ±0.56 × 10−4 | 0.035 | |
| S. Choleraesuis 10708R (spvB-virulence plasmid+) | 3.64 × 10−6 | ±1.46 × 10−4 | 0.035 | |
| E. coli DH5α | 2.23 × 10−1 | ±0.50 × 10−1 | ||
| FII (R100) | S. Typhimurium LT2 pSLT+ | 8.35 × 10−6 | ±1.38 × 10−6 | 0.049 |
| S. Typhimurium LT2 pSLT− | 2.28 × 10−3 | ±1.28 × 10−3 | ||
| S. Typhimurium 98A-28238R (spvB-virulence plasmid−) | 1.69 × 10−6 | ±0.30 × 10−6 | ||
| S. Typhimurium 98A-33516R (spvB-virulence plasmid+, pSLT traS−) | 1.71 × 10−5 | ±0.51 × 10−5 | 0.014, 0.164d | |
| S. Dublin 564R (spvB-virulence plasmid+, pSLT traS−) | 2.44 x10−3 | ±1.22 × 10−3 | 0.466 | |
| S. Choleraesuis 10708R (spvB-virulence plasmid+) | 7.85 × 10−7 | ±1.00 × 10−7 | 0.163 | |
| E. coli DH5α | 6.77 × 10−2 | ±4.80 × 10−2 | ||
a
pSLT, S. Typhimurium LT2 spvB-virulence plasmid.
b
Plasmid transfer frequency was calculated as total number of transconjugants /total number of recipients.
c
Student T-test comparisons between S. Typhimurium LT2 pSLT− strain and other Salmonella isolates.
d
Student T-test comparison between spvB-virulence plasmid−, S. Typhimurium isolate 98A-23238R, and virulence positive isolate 98A-33516R.