Open AccessRegulation of C u( I )/ A g( I ) efflux genes in E scherichia coli by the sensor kinase CusS
Author(s) -
Gudipaty Swapna Aravind,
Larsen Andrew S.,
Rensing Christopher,
McEvoy Megan M.
Publication year - 2012
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2012.02529.x
Subject(s) - periplasmic space , escherichia coli , histidine kinase , biology , efflux , gene , biochemistry , mutant
Two‐component systems are widely used by bacteria to mediate adaptive responses to a variety of environmental stimuli. The CusR / CusS two‐component system in E scherichia coli induces expression of genes involved in metal efflux under conditions of elevated C u( I ) and A g( I ) concentrations. As seen in most prototypical two‐component systems, signal recognition and transmission is expected to occur by ligand binding in the periplasmic sensor domain of the histidine kinase CusS . Although discussed in the extant literature, little experimental evidence is available to establish the role of CusS in metal homeostasis. In this study, we show that the cusS gene is required for C u( I ) and A g( I ) resistance in E . coli and that CusS is linked to the expression of the cusCFBA genes. These results show a metal‐dependent mechanism of CusS activation and suggest an absolute requirement for CusS in C u( I )‐ and A g( I )‐dependent upregulation of cusCFBA expression in E . coli .