Table 1.

Viability of B. subtilis cultures at 20 and 37°Ca

Strainb20°C37°C
No. of cells/ml in stationary phasecNo. of cells/ml in late stationary phasedNo. of cells/ml in stationary phaseeNo. of cells/ml in late stationary phasef
JH6421.0 × 1085 × 1071.0 × 1091.4 × 107
AK6711.0 × 1081 × 1069.5 × 1082.0 × 106
AK671/pDM101.0 × 1085.6 × 1071.0 × 1091.5 × 107
  • a The data are means of at least three experiments with a mean cell concentration error of less than 10%. Numbers of viable cells were determined at various times by dilution and plating on LB plates.

  • b Strain AK671 is a des null mutant constructed as described in Materials and Methods.

  • c Cells were grown in LB medium at 37°C to an optical density at 600 nm of 0.45 and then shifted to 20°C. The cell concentration was determined after 16 h of growth at 20°C, when the cells had reached an optical density at 600 nm of 2.8.

  • d Numbers of viable cells were determined 14 days after the cells reached stationary phase by dilution and plating on LB plates.

  • e Cells were grown in LB medium at 37°C to an optical density at 600 nm of 2.8.

  • f Numbers of viable cells were determined 72 h after the cells reached stationary phase.