Perspective of ions and messengers: an intricate link between potassium, glutamate, and cyclic di-AMP
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Potassium and glutamate are the most abundant ions in every living cell. Whereas potassium plays a major role to keep the cellular turgor and to buffer the negative charges of the nucleic acids, the major function of glutamate is to serve as the universal amino group donor. In addition, both ions are involved in osmoprotection in bacterial cells. Here, we discuss how bacterial cells maintain the homeostasis of both ions and how adaptive evolution allows them to live even at extreme potassium limitation. Interestingly, positively charged amino acids are able to partially replace potassium, likely by buffering the negative charge of DNA. A major factor involved in the control of potassium homeostasis in Gram-positive bacteria is the essential second messenger cyclic di-AMP. This nucleotide is synthesized in response to the potassium concentration and in turn controls the expression and activity of potassium transporters. We discuss the link between the two major ions, DNA and the second messenger c-di-AMP.
KeywordsBacillus subtilis Escherichia coli PH homeostasis Cyclic di-AMP Potassium
We are grateful to Christina Herzberg for helpful discussions. This work was supported by the Deutsche Forschungsgemeinschaft (STU 214/16-1 and CO 1139/2-1) (to JS and FMC, respectively).
- Gundlach J, Herzberg C, Kaever V, Gunka K, Hoffmann T, Weiß M, Gibhardt J, Thürmer A, Hertel D, Daniel R, Bremer E, Commichau FM, Stülke J (2017b) Control of potassium homeostasis is an essential function of the second messenger cyclic di-AMP in Bacillus subtilis. Sci Signal 10:eaal3011CrossRefPubMedGoogle Scholar
- Gunka K, Newman J, Commichau FM, Herzberg C, Rodrigues C, Hewitt L, Lewis RJ, Stülke J (2010) Functional dissection of a trigger enzyme: mutations of the Bacillus subtilis glutamate dehydrogenase RocG that affect catalytic activity and regulatory properties differentially. J Mol Biol 400:815–827CrossRefPubMedGoogle Scholar
- Moscoso JA, Schramke H, Zhang Y, Tosi T, Dehbi A, Jung K, Gründling A (2015) Binding of cyclic di-AMP to the Staphylococcus aureus sensor kinase KdpD occurs via the universal stress protein domain and downregulates the expression of the Kdp potassium transporter. J Bacteriol 198:98–110CrossRefPubMedPubMedCentralGoogle Scholar
- Sambrook J, Fritsch EF, Maniatis T (1989) Molecular cloning: a laboratory manual, 2nd edn. Cold Spring Harbor Laboratory, New YorkGoogle Scholar
- Saum SH, Sydow JF, Palm P, Pfeiffer F, Oesterhelt D, Müller V (2006) Biochemical and molecular characterization of the biosynthesis of glutamine and glutamate, two major compatible solutes in the moderately halophilic bacterium Halobacillus halophilus. J Bacteriol 188:6808–6815CrossRefPubMedPubMedCentralGoogle Scholar