In a new study appearing in PNAS this week, Brandeis Molecular and Cell Biology graduate student Houra Merrikh and co-workers from the Lovett lab identified the E.coli gene iraD as a regulator of the response to oxidative DNA damage in exponentially growing bacteria. Interestingly, the mechanism seems to involve the alternative RNA polymerase sigma factor RpoS, previously characterized as a regulator of expression during the “stationary phase”. Merrikh et al. argue that this response works in parallel with the previously characterized SOS response in protecting growing bacteria from DNA damage.
Sigma factors
January 8, 2009 By