[Signal transduction systems of prokaryotes].

The main components of chemosignaling systems of prokaryotes are multifunctional receptor molecules that include both sensor domains specifically recognizing external signals and effector domains converting these signals into an adequate cell response. This review summarizes and analyzes data of structural-functional organization, molecular mechanisms of action, and regulation of receptor forms of histidine kinases, adenylyl cyclases, diguanylyl cyclases, and phosphodiesterases. These enzymes have been shown to be precursors of the receptor and effector components of the eukaryote hormonal signaling systems. This confirms the hypothesis developed by the authors about formation of the main archetypes of chemosignaling systems at the early evolution stages and about the evolutionary relationship of the signaling systems of prokaryotes and eukaryotes.