In the present study we have for the first time demonstrated direct binding of the DNA binding domain of C. difficile Spo0A to putative target DNA. This work has revealed that aspects of Spo0A binding are conserved between Bacillus and C. difficile (0A box, possible auto-regulation and binding to early sporulation promoters), whereas others are not (the absence of abrB as a direct target in C. difficile, binding to DNA upstream of lplA, ssuA). The effects of Spo0A on toxin production may be similar to those observed for B. thuringiensis [18, 21] . Future work will be aimed at determining the effect of Spo0A on the transcription of the putative target genes, and carry out a comprehensive analysis of Spo0A binding in vivo. The identification of genes affected by Spo0A in C. difficile may shed light on the role of the protein in virulence and pathogenesis of this organism.