A. Oxidative Stress
The Synechocystis microrrays provided a great deal of information on the impact of oxidative stress on this organism. We determined that gene slr1738 encoded a protein similar to PerR in Bacillus subtilis and was induced significantly by peroxide. We constructed a PerR knockout strain and use it to help identify components of the PerR regulon. PerR was next to sll1621 which codes for a peroxiredoxin and share a divergent promoter that is regulated by PerR. We also found that isiA was strongly upregulated by hydrogen peroxide. In addition, slr1894 encoded a protein similar to MrgA in B. subtilis and was also upregulated by peroxide. In addition, we determined that a DMrgA knockout mutation was highly sensitive to peroxide. These results are detailed in publications Li et al.(2004) and Singh et al. (2004).