New Insights into the Non-orthodox Two Component Rcs Phosphorelay System.

Xiao-Peng Guo,Yi-Cheng Sun

doi:10.3389/fmicb.2017.02014

Abstract

The Rcs phosphorelay system, a non-orthodox two-component regulatory system, integrates environmental signals, regulates gene expression, and alters the physiological behavior of members of the Enterobacteriaceae family of Gram-negative bacteria. Recent studies of Rcs system focused on protein interactions, functions, and the evolution of Rcs system components and its auxiliary regulatory proteins. Herein we review the latest advances on the Rcs system proteins, and discuss the roles that the Rcs system plays in the environmental adaptation of various Enterobacteriaceae species.

Highlights

The Regulator of Capsule Synthesis phosphorelay system was originally identified as a positive regulator of colanic acid capsule in Escherichia coli (Gottesman et al, 1985)
Studies have shown that Rcs phosphorelay system is a non-orthodox two-component signal transduction system (TCS) present in members of the Enterobacteriaceae family of Gram-negative bacteria (Gottesman et al, 1985; Allen et al, 1987; Brill et al, 1988; Majdalani and Gottesman, 2005; Huang et al, 2006)
The response regulator RcsB and the membrane-localized hybrid sensor kinase RcsC represent the classical members of bacterial TCS (Stout and Gottesman, 1990), whereas the membranebound sensor RcsD lacks kinase activity (Majdalani and Gottesman, 2005; Clarke, 2010)

Summary

Introduction

The Regulator of Capsule Synthesis phosphorelay system was originally identified as a positive regulator of colanic acid capsule in Escherichia coli (Gottesman et al, 1985). RcsB can form homodimer or heterodimers with the auxiliary proteins, which interact with a conserved motif in target genes to modulate their transcription. The involvement of a hybrid sensor kinase, additional functional domains, multiple phosphodonors, several acceptor sites, and a variety of auxiliary proteins results in a high complex signaling system, which likely increases the flexibility of the Rcs system and provides multiple checkpoints to facilitate precise regulation of gene expression.

Results

Conclusion