FIG. 3.

Transcription of sporulation sigma factor genes in C. perfringens SM101, KM1 (sigK mutant), and KM2 (sigE mutant) strains. RT-PCR of the four sporulation sigma factor genes in strains SM101, KM1, and KM2. Samples were collected during early log phase (EL) (OD₆₀₀ of 0.1) and early stationary phase (ES) (OD₆₀₀ of 1.0). + indicates reactions in which reverse transcriptase was added to the reaction. − indicates those reactions in which reverse transcriptase was not included in the reaction (negative control). Products were viewed on an ethidium bromide-stained 2% agarose gel.