The peroxide stress response of Bacillus licheniformis.

The oxidative stress response of Bacillus licheniformis after treatment with hydrogen peroxide was investigated at the transcriptome, proteome and metabolome levels. In this comprehensive study, 84 proteins and 467 transcripts were found to be up or downregulated in response to the stressor. Among the upregulated genes were many that are known to have important functions in the oxidative stress response of other organisms, such as catalase, alkylhydroperoxide reductase or the thioredoxin system. Many of these genes could be grouped into putative regulons by genomic mining. The occurrence of oxidative damage to proteins was analyzed by a 2-DE-based approach. In addition, we report the induction of genes with hitherto unknown functions, which may be important for the specific oxidative stress response of B. licheniformis. The genes BLi04114 and BLi04115, that are located adjacent to the catalase gene, were massively induced during peroxide stress. Furthermore, the genes BLi04207 and BLi04208, which encode proteins homologous to glyoxylate cycle enzymes, were also induced by peroxide. Metabolomic analyses support the induction of the glyoxylate cycle during oxidative stress in B. licheniformis.