Table 2.

Sporulation of the shaA mutant and the wild type

StrainRelevant genotypeMediumaNo. (CFU/ml) of:Frequency (%)
Viable cellsSpores
UOT1285 shaA+ 2× SG1.3 × 109 5.3 × 108 41
UOT1285 shaA+ 2× SG + 30 mM NaCl7.8 × 108 5.0 × 108 64
UOT1285 shaA+ 2× SG + 50 mM NaCl7.7 × 108 5.5 × 108 71
SK6 shaA::neo 2× SG5.2 × 108 1.1 × 107b 2.1
SK6 shaA::neo 2× SG + 30 mM NaCl4.5 × 108 <10<2 × 10−6
SK6 shaA::neo 2× SG + 50 mM NaCl1.4 × 108 <10<7 × 10−6
UOT1285 shaA+ S7K3.6 × 108 2.5 × 108 69
UOT1285 shaA+ S7K + 20 mM NaCl3.6 × 108 2.1 × 108 58
UOT1285 shaA+ S7K + 50 mM NaCl3.4 × 108 2.0 × 108 59
UOT1285 shaA+ S7K + 100 mM NaCl4.1 × 108 2.0 × 108 49
UOT1285 shaA+ S7K + 50 mM KCl3.0 × 108 2.7 × 108 90
SK6 shaA::neo S7K3.0 × 108 1.1 × 108 37
SK6 shaA::neo S7K + 20 mM NaCl3.2 × 108 3.5 × 107 11
SK6 shaA::neo S7K + 50 mM NaCl1.1 × 107 6.8 × 105 6.2
SK6 shaA::neo S7K + 100 mM NaCl1.5 × 107 5.0 × 102.9 × 10−4
SK6 shaA::neo S7K + 50 mM KCl2.2 × 108 1.3 × 108 59
  • a The 2× SG liquid medium (0.1% glucose) contains 18 mM contaminating Na+. The S7K liquid medium (0.1% glucose) contains less than 1 mM contaminating Na+.

  • b The spore production fluctuated between 105 and 107.