Table 2.

rep recA dnaK mutant cells present a plating defect at 30°Ca

StrainMutant genotypeExponential culturesOvernight cultures
CFU/mlRelative valueCFU/mlRelative value
MC1061Wild type1.1 × 108 ± 3.5 × 107 13.8 × 109 ± 7 × 107 1
JJC526 rep 1.3 × 108 ± 1.1 × 107 1.22.8 × 109 ± 4.7 × 108 0.74
JJC527 recA 4.7 × 107 ± 1.5 × 107 0.432.4 × 109 ± 2.5 × 108 0.63
TS154 dnaK306 1.4 × 108 ± 5.8 × 107 1.32 × 109 ± 2 × 108 0.5
JJC529 dnaK306 recA 2 × 107 ± 1.3 × 107 0.181.2 × 109 ± 8 × 108 0.3
JJC528 dnaK306 rep 4 × 107 ± 3.7 × 107 0.366.6 × 108 ± 2.5 × 108 0.17
JJC530 rep recA 2.4 × 107 ± 1.8 × 106 0.238.7 × 108 ± 3.7 × 108 0.22
JJC531 dnaK306 rep recA 3.4 × 106 ± 4.4 × 106 0.0312.9 × 108 ± 1.4 × 108 0.07
CAG9270Wild type1.3 × 108 ± 1.8 × 107 11.8 × 109 ± 8 × 108 1
JJC634 rep 8 × 107 ± 3.4 × 107 0.611.6 × 109 ± 1.4 × 108 0.9
JJC633 recA 1 × 108 ± 2.3 × 107 0.772.5 × 109 ± 2 × 108 1.4
CAG9271 dnaK756 1.4 × 108 ± 4.5 × 107 1.11.3 × 109 ± 2 × 108 0.72
JJC546 dnaK756 recA 7 × 107 ± 3.4 × 107 0.539.5 × 108 ± 3.4 × 108 0.52
JJC547 dnaK756 rep 2.8 × 107 ± 2.3 × 107 0.215 × 108 ± 5 × 107 0.28
JJC636 rep recA 4.5 × 106 ± 2 × 106 0.034 × 108 ± 3 × 108 0.22
JJC677 dnaK756 rep recA 1.2 × 106 ± 1.2 × 106 0.0091.4 × 107 ± 9 × 106 0.008
  • a Results are the average of three or four independent experiments. Cells were grown at 30°C and plated at the same temperature. Cells in exponential phase were harvested at an OD of 0.3 to 0.6 (most often at 0.4 to 0.5). Saturated cultures reached an OD of 1.5 to 4, depending on the strain. In order to compare the different cultures, results normalized for an OD of 0.4 (exponential cultures) or 2 (overnight cultures) were calculated.