@ARTICLE{10.3389/fmicb.2016.01888, AUTHOR={Armitano, Joshua and Redder, Peter and GuimarĂ£es, Vanessa A. and Linder, Patrick}, TITLE={An Essential Factor for High Mg2+ Tolerance of Staphylococcus aureus}, JOURNAL={Frontiers in Microbiology}, VOLUME={7}, YEAR={2016}, URL={https://www.frontiersin.org/articles/10.3389/fmicb.2016.01888}, DOI={10.3389/fmicb.2016.01888}, ISSN={1664-302X}, ABSTRACT={Internal bacterial concentration of Mg2+, the most abundant divalent cation in living cells, is estimated to be in the single millimolar range. However, many bacteria will thrive in media with only micromolars of Mg2+, by using a range of intensely studied and highly efficient import mechanisms, as well as in media with very high magnesium concentration, presumably mediated by currently unknown export mechanisms. Staphylococcus aureus has a particularly high Mg2+ tolerance for a pathogen, growing unimpaired in up to 770 mM Mg2+, and we here identify SA0657, a key factor in this tolerance. The predicted domain structure of SA0657 is shared with a large number of proteins in bacteria, archaea and even eukarya, for example CorB from Salmonella and the human CNNM protein family. One of the shared domains, a CBS pair potentially involved in Mg2+ sensing, contains the conserved Glycine326 which we establish to be a key residue for SA0657 function. In light of our findings, we propose the name MpfA, Magnesium Protection Factor A, for SA0657.} }