TABLE 2.
Transformation of S. typhimurium with chromosomal DNA
| Straina | rec mut genotype | No. of transformants/109 CFUb
|
|
|---|---|---|---|
| S. typhimurium | S. typhi | ||
| MA2290 | rec+ mut+ | 0 | 0 |
| MA5114 | rec+ mutS | 0 | 1 |
| MA5133 | recD mut+ | 21 | 0 |
| MA5116 | recD mutS | 12 | 4 |
| MA5031 | recBD sbcE mut+ | 41 | 1 |
| MA5145 | recBD sbcE mutS | 33 | 17 |
a
Strains MA5114, MA5116, and MA5145 were derived from S. typhimurium strains MA2290, MA5133 and MA5031, respectively (Table 1), upon introducing the mutS171::Tn10dCm insertion.
b
Chromosomal DNA (1 to 5 μg), mildly sheared by vortexing for 1 to 2 min, was used for transformation (carried out as described for Table 1). Selection was to prototrophy (Leu+). Data are the averages of three independent determinations.