Title: Divergent distribution of the sensor kinase CosS in non-thermophilic Campylobacter species and its functional incompatibility with the Campylobacter jejuni CosR
Authors: Hwang S, Miller WG, Ryu S, Jeon B
Journal: PLoS One
Accepted date: 2014 Jan 27
Interpretive summary: In bacteria, genes are often regulated through two component systems. A two component system is composed of two proteins, a sensor and regulator. The sensor protein detects an environmental signal and in response adds a phosphate group to the regulator protein. The phosphorylated regulator protein then turns on one or more genes. The food-borne pathogen Campylobacter contains several two component systems, whose signal and regulated genes are as yet unknown. One of these is the CosRS system. CosRS is unusual in that the sensor protein in the pair, CosS, described here for the first time, is only found in campylobacters that grow at lower temperatures, the so-called non-thermophilic campylobacter group. In this study it was determined that the CosS sensor protein did indeed add a phosphate group to its CosR counterpart but not to CosR proteins of the other campylobacter group, the “thermophilic” campylobacters. Although there is a clear distinction between the two types of CosR proteins between campylobacters that grow under different temperatures, mutation analysis indicated that the CosR protein was not responsible for this growth temperature difference. Additionally, CosR mutations did not affect sensitivity of campylobacters to oxygen compounds. Thus, the role of the CosRS system remains to be determined.
Related projects: Molecular Biology of Human Pathogens Associated with Food