Histidine and aspartate phosphorylation: two-component systems and the limits of homology

Trends Biochem Sci. 1994 Nov;19(11):485-90. doi: 10.1016/0968-0004(94)90135-x.


Autophosphorylating histidine kinase and response-regulator domains constitute the building blocks of two-component signaling systems. These systems use a unique phosphotransfer chemistry to regulate many aspects of bacterial physiology. Homologous systems are now being found in eukaryotes. Despite their common mechanism of phosphotransfer, the two-component systems display an extensive diversity in the arrangement of their domains, and flexibility in their roles in different signal transduction circuits.

Publication types

  • Review

MeSH terms

  • Animals
  • Aspartic Acid / metabolism*
  • Histidine / metabolism*
  • Phosphorylation
  • Sequence Homology, Amino Acid
  • Signal Transduction / physiology


  • Aspartic Acid
  • Histidine