Multi omics based characterization of various stress responses in Bacillus subtilis Bacillus subtilis Multi omics SRM (single reaction monitoring) Osmostress Zentralkohlenstoffmetabolismus Anpassungsreaktionen Central carbon metabolism adaptational responses The soil bacterium Bacillus subtilis is capable of surviving most of the ensuing environmental stress conditions. The dynamic nature of the soil habitat is manifested with varying amounts of nutrients frequent flooding drying and variation of other growth parameters like temperature acidity aeration etc. In order to survive in these conditions B. subtilis has evolved to employ very complex adaptational responses. These adaptational responses are often multi faceted; hence comprehensive understanding of the adaptational responses requires generation and integration of data on multi omics level. Hence multi omics based detailed analysis was performed for the molecules involved in the central carbon metabolism (CCM) and proline biosynthesis pathway. In the current study two major stress conditions were extensively investigated: 1) energy limitation starvation which is achieved by limiting glucose in the growth medium 2) osmostress resulting from frequent drying out of soil which is simulated by adding 1.2 M NaCl to the growth medium. In addition to osmostress the naturally available osmoprotectant glycine betaine (GB) was supplemented to understand the simultaneous influence of osmostress and osmoprotection on cellular physiology. To measure absolute protein abundances by mass spectrometry a targeted approach (SRM single reaction monitoring) using stable heavy isotope labeled artificial standard proteins known as QconCATs was optimized and implemented in the current ...