TABLE 3.
Straina | Plasmidb | Log 10 no. of transformants/μg plasmid DNAc |
|
---|---|---|---|
Without in vivo methylation | With in vivo methylation | ||
Bacteroides fragilis NCTC9343 | pLYL05 | 5.36 ± 0.04 | 7.23 ± 0.05 |
Bacteroides fragilis YCH46 | pLYL05 | 4.42 ± 0.34 | 6.25 ± 0.08 |
Bacteroides thetaiotaomicron VPI-5482 | pNLY1 | 3.43 ± 0.65 | 4.45 ± 0.25 |
Bacteroides vulgatus ATCC 8482 | pLYL05 | 3.15 ± 0.16 | 2.56 ± 0.11 |
Competent cells were prepared from 48-h cultures and electroporated with 0.45 μg DNA of each plasmid indicated. After 3 h of postpulse incubation, cells were spread onto GAM agar plates containing selective antibiotics corresponding to the plasmid used.
All plasmids were purified from E. coli laboratory strain HB101. pNLY1 was used for B. thetaiotaomicron strain VPI-5482 as this strain is cefoxitin resistant.
The data are means ± standard deviations calculated from three independent experiments.