Ser/Thr/Tyr protein phosphorylation in the archaeon Halobacterium salinarum--a representative of the third domain of life

PLoS One. 2009;4(3):e4777. doi: 10.1371/journal.pone.0004777. Epub 2009 Mar 10.

Abstract

In the quest for the origin and evolution of protein phosphorylation, the major regulatory post-translational modification in eukaryotes, the members of archaea, the "third domain of life", play a protagonistic role. A plethora of studies have demonstrated that archaeal proteins are subject to post-translational modification by covalent phosphorylation, but little is known concerning the identities of the proteins affected, the impact on their functionality, the physiological roles of archaeal protein phosphorylation/dephosphorylation, and the protein kinases/phosphatases involved. These limited studies led to the initial hypothesis that archaea, similarly to other prokaryotes, use mainly histidine/aspartate phosphorylation, in their two-component systems representing a paradigm of prokaryotic signal transduction, while eukaryotes mostly use Ser/Thr/Tyr phosphorylation for creating highly sophisticated regulatory networks. In antithesis to the above hypothesis, several studies showed that Ser/Thr/Tyr phosphorylation is also common in the bacterial cell, and here we present the first genome-wide phosphoproteomic analysis of the model organism of archaea, Halobacterium salinarum, proving the existence/conservation of Ser/Thr/Tyr phosphorylation in the "third domain" of life, allowing a better understanding of the origin and evolution of the so-called "Nature's premier" mechanism for regulating the functional properties of proteins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / metabolism*
  • Archaea
  • Biological Evolution*
  • Genome, Bacterial
  • Halobacterium salinarum / genetics
  • Halobacterium salinarum / metabolism*
  • Phosphorylation
  • Proteomics / methods*
  • Serine / metabolism
  • Signal Transduction*
  • Threonine / metabolism
  • Tyrosine / metabolism

Substances

  • Amino Acids
  • Threonine
  • Tyrosine
  • Serine