Table 2

Pre-rRNA and mature rRNA quantitation during E. coli growth phases

Time point (min)OD600CFU/mlRateaDoublingbGeneration time (min)rRNAcPre-rRNAcRatioGrowth phase
Overnight culture2.3076.67E + 096,00922,720Stationary phase
005.90E + 055,94211054Lag phase
3005.70E + 0528,42745762
600.0038.63E + 050.181.2050.0855,27869679Log phase
900.0082.30E + 060.432.8321.1978,74197081
1200.0246.20E + 060.432.8621.0091,049120076
1500.0681.91E + 070.493.2418.5198,782523189
1800.1756.53E + 070.533.5516.8861,571235262
2100.4092.30E + 080.553.6416.5038,033208183
2400.7075.27E + 080.362.3925.1429,801114260Early stationary phase
2701.0951.17E + 090.352.3026.1419,61042466
3001.4662.33E + 090.302.0030.0013,16225536
3301.6863.23E + 090.140.9463.747,60811665Stationary phase
3601.8344.43E + 090.140.9165.875,7348723
3901.9575.03E + 090.060.37163.814,8997706
4202.0515.73E + 090.060.38159.686,23061,049
  • a Growth rate in log units per 30 min.

  • b Doublings per hour.

  • c Copies per cell.