2010 Volume 73 Issue 1 Pages 12-18
Our group recently determined the complete genome sequence of Rothia mucilaginosa strain DY-18, a clinical isolate from a persistent periapical periodontitis lesion. We bioinformatically determined that this strain possesses two sigma factors, one of which is a primary sigma factor that recognizes housekeeping promoters, and the other is an additional sigma factor whose promoter-binding activity may be regulated in response to physiolosical and environmental cues. Furthermore, the gene encoding the additional sigma factor is arranged in an operon-like structure with its cognate anti-sigma factor gene. Through multiple alignment analysis of the anti-sigma factor and its homologs, we found a conserved redox motif within these proteins. On the basis of these results, it was suggested that this sigma-antisigma regulatory system is a response to oxidative stress.
