TABLE 2.
Lethality of lexA null mutations in strain LT2
| Transductional recipient
|
No. of selected transductants obtained with indicated donor (constant phage input, 3 × 109 PFU)
|
||||
|---|---|---|---|---|---|
| Strain | Relevant genotype | Genetic background if other than LT2 | lexA40::Kan (TT17653)a | lexA41::Cam (TT22613)b | (Cam)lexA33(Ind−) (TT22964)b |
| TR10000 | Wild type (LT2) recA+lexA+ | 1c | 3c | 444 | |
| TT23205 | sulA46::Spc | 12d | 22d | 524 | |
| TT23204 | sulA46::Spc (no Fels-2 or Gifsy-1 or -2) | SLT2 | 476 | 368 | 492 |
| TT22888 | Duplication (lexA+/lexA+) | 348 | 396 | 532 | |
| TT23203 | sulA46::Spc duplication (lexA+/lexA+) | 460 | 364 | 428 | |
| TT23296 | sulA46::Spc (no Fels-2 or Gifsy-1 or -2) | DB9071 | 480 | 512 | 500 |
| TT23298 | sulA46::Spc (no Gifsy-2) | ATCC 14028 | 43d | 6d | 552 |
| TT23299 | sulA46::Spc (no Gifsy-1 or -2) | ATCC 14028 | 20d | 10d | 548 |
| TT23379 | sulA46::Spc (no Fels-2) | DB7000 | 340e | 516e | 515 |
| TT23649 | tum(Fels-2)::Cam(sw) sulA+ | 3c | (656)f | ||
| TT23650 | tum(Fels-2)::Cam(sw) sulA46::Spc | 306e | (678)f | ||
a
Selection was for resistance to kanamycin on NB containing 50 μg of kanamycin per ml.
b
Selection was for resistance to chloramphenicol (Cam) on NB containing 25 μg of chloramphenicol per ml.
c
Healthy colonies that contained a duplication of the lexA gene.
d
Mixture of healthy colonies and flat, small colonies. Healthy colonies contained a duplication of the lexA gene.
e
Colonies were virtually all flat and small.
f
Since this recipient was already Camr, a hisC::Kan (TT16803) marker strain was used as the donor instead of (Cam)lexA33; transductants were selected on NB containing kanamycin (50 μg/ml).