Widespread bacterial protein histidine phosphorylation revealed by mass spectrometry-based proteomics.

For decades, major difficulties in analyzing histidine phosphorylation have limited the study of phosphohistidine signaling. Here we report a method revealing widespread and abundant protein histidine phosphorylation in Escherichia coli. We generated an extensive E. coli phosphoproteome data set, in which a remarkably high percentage (∼10%) of phosphorylation sites are phosphohistidine sites. This resource should help enable a better understanding of the biological function of histidine phosphorylation.