Tyrosine phosphorylation as a widespread regulatory mechanism in prokaryotes.

Abstract

Phosphorylation events modify bacterial and archaeal proteomes, imparting cells with rapid and reversible responses to specific environmental stimuli or niches. Phosphorylated proteins are generally modified at one or more serine, threonine, or tyrosine residues. Within the last ten years, increasing numbers of global phosphoproteomic surveys of prokaryote species has revealed an abundance of tyrosine phosphorylated proteins. In some cases, novel phosphorylation-dependent regulatory paradigms for cell division, gene transcription, and protein translation have been identified suggesting that a wide scope of prokaryotic physiology remains to be characterized. Recent observations of bacterial proteins with putative phosphotyrosine binding pockets or SH2-like domains suggest the presence of phosphotyrosine- dependent protein interaction networks. Herein, in this minireview we focus on protein tyrosine phosphorylation, a post-translational modification once thought to be rare in prokaryotes yet has emerged as an important regulatory facet in microbial biology.