The cyclic dinucleotide c-di-AMP is an allosteric regulator of metabolic enzyme function

Cell. 2014 Sep 11;158(6):1389-1401. doi: 10.1016/j.cell.2014.07.046.

Abstract

Cyclic di-adenosine monophosphate (c-di-AMP) is a broadly conserved second messenger required for bacterial growth and infection. However, the molecular mechanisms of c-di-AMP signaling are still poorly understood. Using a chemical proteomics screen for c-di-AMP-interacting proteins in the pathogen Listeria monocytogenes, we identified several broadly conserved protein receptors, including the central metabolic enzyme pyruvate carboxylase (LmPC). Biochemical and crystallographic studies of the LmPC-c-di-AMP interaction revealed a previously unrecognized allosteric regulatory site 25 Å from the active site. Mutations in this site disrupted c-di-AMP binding and affected catalytic activity of LmPC as well as PC from pathogenic Enterococcus faecalis. C-di-AMP depletion resulted in altered metabolic activity in L. monocytogenes. Correction of this metabolic imbalance rescued bacterial growth, reduced bacterial lysis, and resulted in enhanced bacterial burdens during infection. These findings greatly expand the c-di-AMP signaling repertoire and reveal a central metabolic regulatory role for a cyclic dinucleotide.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Allosteric Regulation
  • Amino Acid Sequence
  • Animals
  • Bacteriolysis
  • Binding Sites
  • Crystallography, X-Ray
  • Dinucleoside Phosphates / metabolism*
  • Host-Pathogen Interactions
  • Listeria monocytogenes / enzymology
  • Listeria monocytogenes / growth & development
  • Listeria monocytogenes / metabolism*
  • Listeriosis / microbiology
  • Mice
  • Models, Molecular
  • Molecular Sequence Data
  • Pyruvate Carboxylase / chemistry*
  • Pyruvate Carboxylase / metabolism*

Substances

  • Dinucleoside Phosphates
  • cyclic diadenosine phosphate
  • Pyruvate Carboxylase

Associated data

  • PDB/4QSH
  • PDB/4QSK
  • PDB/4QSL