Table 3.

Comparison of specific activity of sspF-lacZproduct from spores of different B. subtilis strains

StrainMajor SASPaSp act of sspF-lacZproductb
PS848α and β1.8 ± 0.3
PS850None5.6 ± 1.2
PS1612α, β, and SspCw t 1.7 ± 0.3
PS1613SspCw t 1.8 ± 0.3
PS1614α, β, and SspCa l a 2.2 ± 0.4
PS1615SspCa l a 6.8 ± 1.5
  • a The major SASP noted are only the α/β-type SASP.

  • b Aliquots of 36-h cultures in 2× SG medium were extracted with urea and sodium dodecyl sulfate to remove spore coats and inactivate enzymes not in spores. Spores were then disrupted with lysozyme, and extracts were assayed for β-galactosidase and glucose dehydrogenase. The sspF-lacZ product-specific activities are given as the ratio of the ΔOD420/30 min/0.3 ml extract in the β-galactosidase assay to the ΔOD340/2 min/0.1 ml extract in the glucose dehydrogenase assay and are averages of duplicate assays on spores from three separate experiments. Values for β-galactosidase in spores without alacZ fusion have been subtracted from those for β-galactosidase-specific activity; in all cases this value was less than 10% of that in spores with an sspF-lacZ fusion.