TABLE 2.

Colony formation efficiency of prpE mutants^a

Strain	IPTG concn (mM)		No. of spores	No. of colonies	Efficiency of colony formation (%)
	In medium	On plates
168 (wild-type)			1.9 × 109	1.8 × 109	95
MM1325 (ΔprpE)			2.8 × 109	1.7 × 108	6
MM1503 (prpE-gfp)			5.3 × 107	4.7 × 107	89
MM1502 (ΔprpE amyE::pSpac-prpE)			1.2 × 109	4.0 × 108	33
	0.5	1.3 × 109	5.5 × 108	42
	0.5	1.6 × 109	1.3 × 109	80
	0.5	0.5	8.0 × 109	5.8 × 109	73
	0.5	1	1.2 × 109	1.1 × 109	92

^aCells were induced to sporulate in Sterlini-Mandelstam sporulation medium, and spore suspensions were prepared as described in Materials and Methods. Spores were counted in a Thoma cell and plated on LB medium. After a 5-day incubation at 37°C, colonies were counted, and the efficiency of colony formation was calculated.