Coping with an Essential Poison: a Genetic Suppressor Analysis Corroborates a Key Function of c-di-AMP in Controlling Potassium Ion Homeostasis in Gram-Positive Bacteria

J Bacteriol. 2018 May 24;200(12):e00166-18. doi: 10.1128/JB.00166-18. Print 2018 Jun 15.


Cyclic di-AMP (c-di-AMP) is an important second messenger in bacteria. In most Firmicutes, the molecule is required for growth in complex media but also toxic upon accumulation. In an article on their current study, Zarrella and coworkers present a suppressor analysis of a Streptococcus pneumoniae strain that is unable to degrade c-di-AMP (T. M. Zarrella, D. W. Metzger, and G. Bai, J Bacteriol 200:e00045-18, 2018, Their study identifies new links between c-di-AMP and potassium homeostasis and supports the hypothesis that c-di-AMP serves as a second messenger to report about the intracellular potassium concentrations.

Keywords: Streptococcus pneumoniae; diadenylate cyclase; phosphodiesterase; potassium uptake; second messenger.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cyclic AMP / metabolism*
  • Gene Expression Regulation, Bacterial
  • Gram-Positive Bacteria / genetics
  • Gram-Positive Bacteria / metabolism*
  • Homeostasis
  • Phosphoric Diester Hydrolases / genetics
  • Phosphoric Diester Hydrolases / metabolism
  • Phosphorus-Oxygen Lyases / genetics
  • Phosphorus-Oxygen Lyases / metabolism
  • Potassium / metabolism*
  • Second Messenger Systems


  • Cyclic AMP
  • Phosphoric Diester Hydrolases
  • Phosphorus-Oxygen Lyases
  • Potassium