Global impact of protein arginine phosphorylation on the physiology of Bacillus subtilis. Bacillus subtilis subsp. subtilis str. 168

Reversible protein phosphorylation is an important and ubiquitous protein modification in all living cells. We report that protein arginine phosphorylation plays a physiological significant role for the regulation of protein activity. We detected 121 arginine phospho-sites for 87 proteins in the Gram-positive model organism Bacillus subtilis in vivo. Moreover, we provide evidences that arginine phosphorylations are involved in the fine-tuned signal transduction of many critical cellular processes, such as protein degradation, motility, competence, stringent and stress response. Our results suggest that in B. subtilis the activity of a protein arginine phosphatase allows a fast regulation of protein activity by protein arginine kinases and that protein arginine phosphorylations play an important role as a reversible post-translational modification in bacteria. Overall design: Cells were grown under vigorous agitation at 37 °C in a defined medium (Stülke et al., 1993, J Gen Microbiol 139, 2041-2045). Samples were taken at OD500 0.4 and 1h upon entry into stationary phase. Microarray hybridizations were performed with RNA from three biological replicates. The individual samples were labeled with Cy5; a reference pool containing equal amounts of RNA from all 10 samples was labeled with Cy3.