Two-component systems (TCSs) are modular signaling circuits that regulate diverse aspects of microbial physiology in response to environmental cues. These molecular circuits comprise a sensor histidine kinase (HK) protein that contains a conserved histidine residue, and an effector response regulator (RR) protein with a conserved aspartate residue. HKs play a major role in bacterial signaling, since they perceive specific stimuli, transmit the message across the cytoplasmic membrane, and catalyze their own phosphorylation, and the trans-phosphorylation and dephosphorylation of their cognate response regulator. The molecular mechanisms by which HKs co-ordinate these functions have been extensively analyzed by genetic, biochemical, and structural approaches. Here, we describe the most common modular architectures found in bacterial HKs, and address the operation mode of the individual functional domains. Finally, we discuss the use of these signaling proteins as drug targets or as sensing devices in whole-cell biosensors with medical and biotechnological applications.
Many dietary plants possess high levels of 18-carbon containing lipids from both omega-6 and omega-3 unsaturated fatty acids (e.g., linoleic and alpha-linolenic acid, respectively). These dietary lipids can be metabolized to lipid mediators collectively termed octadecanoids, which can in turn interact with immune cells (e.g., macrophages, eosinophils) to exert a number of potent biological effects. These octadecanoid lipid mediators have been little studied and represent an exciting new area of lipid biochemistry. For further information, see the review in this issue by Quaranta and colleagues (pages 1569–1582). Cover image credit: Emmanuelle Chevallier.
The role of sensory kinase proteins in two-component signal transduction
Adrián F. Alvarez, Dimitris Georgellis; The role of sensory kinase proteins in two-component signal transduction. Biochem Soc Trans 16 December 2022; 50 (6): 1859–1873. doi: https://doi.org/10.1042/BST20220848
Download citation file: