The Cyclic di-AMP Signaling Project
Updated Jan. 2020
Cyclic di-AMP (c-di-AMP, cdA) was first discovered in 2008, and this second messenger
has crucial roles in many bacterial processes, including central
metabolism, cell wall metabolism, DNA repair, potassium homeostasis,
osmotic regulation, sporulation, stress response, antibiotic resistance,
biofilm formation and virulence. It is essential in many bacteria, and riboswitches
and proteins have been identified as its sensors.
It also has an important role in host-pathogen interactions.
Using a chemical proteomics approach, a set of proteins that interact with c-di-AMP was identified
in Listeria monocytogenes. The biochemical and physiological effects
of c-di-AMP binding to these target proteins were then
characterized. The molecular basis for the binding was also determined.
Major findings from this project
- The structure of Listeria monocytogenes pyruvate carboxylase (LmPC) in complex
with c-di-AMP has been determined, the first structure of c-di-AMP bound to a protein
c-di-AMP is bound at the dimer interface of the CT domain of LmPC, showing pi-stacking,
hydrogen-bonding and van der Waals interactions with the enzyme.
There are large conformational changes in LmPC upon c-di-AMP binding. The four monomers of
LmPC assume a single conformation in the complex, while they have large variability in the
free enzyme. This 'freezing' of the enzyme may be the molecular basis of the inhibitory
effect of c-di-AMP.
Mutations in the c-di-AMP binding site can abolish binding.
Reduced levels of c-di-AMP in Listeria causes a metabolic imbalance, which affects
the growth of this bacterium in host cells.
PC enzyzmes from other bacteria that have a conserved binding site are also sensitive
to c-di-AMP, such as that from Lactococcus lactis (LlPC).
Publications from this project
K. Sureka,* P.H. Choi,* M. Precit, M. Delince, D.A. Pensinger, T.N. Huynh, A.R. Jurado, Y.A. Goo, M. Sadilek, A.T. Iavarone, J.-D. Sauer, L. Tong$ & J.J. Woodward.$ (2014). The cyclic dinucleotide c-di-AMP is an allosteric regulator of metabolic enzyme function. Cell, 158, 1389-1401. (*-equal first authors, $-co-corresponding authors)
T.N. Huynh*, S. Luo*, D.A. Pensinger, J.-D. Sauer, L. Tong$ & J.J. Woodward.$. (2015). An HD-domain phosphodiesterase mediates cooperative hydrolysis of c-di-AMP to affect bacterial growth and virulence. Proc. Natl. Acad. Sci. USA, 112, E747-E756. (*-equal first authors, $-co-corresponding authors)
P.H. Choi*, K. Surekha*, J.J. Woodward$ & L. Tong.$ (2015). Molecular basis for the recognition of cyclic-di-AMP by PstA, a PII-like signal transduction protein. MicrobiologyOpen, 4, 361-374. (*-equal first authors, $-co-corresponding authors)
T.N. Huynh*, P.H. Choi*, K. Sureka, H.E. Ledvina, J. Campillo, L. Tong$ & J.J. Woodward.$ (2016). Cyclic di-AMP targets the cystathionine beta-synthase domain of the osmolyte transporter OpuC. Mol. Microbiol. 102, 233-243. (*-equal first authors, $-co-corresponding authors)
A.P. McFarland, S. Luo, F. Ahmed-Qadri, M. Zuck, E.F. Thayer, Y.A. Goo, K. Hybiske, L. Tong & J.J. Woodward. (2017). Sensing of bacterial cyclic dinucleotides by the oxidoreductase RECON promotes NF-kB activation and shapes a proinflammatory antibacterial state. Immunity, 46, 433-445.
A.T. Whiteley, N.E. Garelis, B.N. Peterson, P.H. Choi, L. Tong, J.J. Woodward & D.A. Portnoy. (2017). c-di-AMP modulates Listeria monocytogenes central metabolism to regulate growth, antibiotic resistance, and osmoregulation. Mol. Microbiol., 104, 212-233.
P.H. Choi, T.M.N. Vu, H.T. Pham, J.J. Woodward, M.S. Turner & L. Tong. (2017). Structural and functional studies of pyruvate carboxylase regulation by cyclic-di-AMP in lactic acid bacteria. Proc. Natl. Acad. Sci. USA, 114, E7226-E7235.
Funding for this project
NIH R01AI116669 (2015-2020)
© copyright 2019-2020, Liang Tong.