Fluorescence of a P<i>spoIIR</i>-SNAP fusion in strain 630Δerm and in a <i>spo0A</i>, <i>sigF</i> or <i>sigE</i> mutant.

<p>Cells of the <i>C. difficile</i> 630Δerm strain, and of the <i>spo0A</i>, <i>sigF</i> and <i>sigE</i> mutants carrying a P<i>_spoIIR</i>-SNAP^Cd transcriptional fusion in a multicopy plasmid were collected 24 h of following inocculation in SM broth. Cells were labelled with the fluorescent substrate TMR to allow localization of SNAP^Cd production driven by the <i>spoIIR</i> promoter, stained with the DNA marker DAPI and the membrane dye MTG and examined by phase contrast and fluorescence microscopy.