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Frontiers in Cellular and Infection... 2024This study unveils the intricate functional association between cyclic di-3',5'-adenylic acid (c-di-AMP) signaling, cellular bioenergetics, and the regulation of...
BACKGROUND
This study unveils the intricate functional association between cyclic di-3',5'-adenylic acid (c-di-AMP) signaling, cellular bioenergetics, and the regulation of lipopolysaccharide (LPS) profile in , a Gram-negative obligate anaerobe considered as a keystone pathogen involved in the pathogenesis of chronic periodontitis. Previous research has identified variations in LPS profile as a major virulence factor, yet the underlying mechanism of its modulation has remained elusive.
METHODS
We employed a comprehensive methodological approach, combining two mutants exhibiting varying levels of c-di-AMP compared to the wild type, alongside an optimized analytical methodology that combines conventional mass spectrometry techniques with a novel approach known as FLAT.
RESULTS
We demonstrate that c-di-AMP acts as a metabolic nexus, connecting bioenergetic status to nuanced shifts in fatty acid and glycosyl profiles within LPS. Notably, the predicted regulator gene , serving as a potent regulator of c-di-AMP synthesis, was found essential for producing N-acetylgalactosamine and an unidentified glycolipid class associated with the LPS profile.
CONCLUSION
The multifaceted roles of c-di-AMP in bacterial physiology are underscored, emphasizing its significance in orchestrating adaptive responses to stimuli. Furthermore, our findings illuminate the significance of LPS variations and c-di-AMP signaling in determining the biological activities and immunostimulatory potential of LPS, promoting a pathoadaptive strategy. The study expands the understanding of c-di-AMP pathways in Gram-negative species, laying a foundation for future investigations into the mechanisms governing variations in LPS structure at the molecular level and their implications for host-pathogen interactions.
Topics: Porphyromonas gingivalis; Lipopolysaccharides; Signal Transduction; Virulence Factors; Gene Expression Regulation, Bacterial; Energy Metabolism; Dinucleoside Phosphates; Fatty Acids; Humans; Bacterial Proteins
PubMed: 38933693
DOI: 10.3389/fcimb.2024.1418651 -
Bioorganic Chemistry Jul 2024Adenylate kinase (AK) plays a crucial role in the metabolic monitoring of cellular adenine nucleotide homeostasis by catalyzing the reversible transfer of a phosphate...
Adenylate kinase (AK) plays a crucial role in the metabolic monitoring of cellular adenine nucleotide homeostasis by catalyzing the reversible transfer of a phosphate group between ATP and AMP, yielding two ADP molecules. By regulating the nucleotide levels and energy metabolism, the enzyme is considered a disease modifier and potential therapeutic target for various human diseases, including malignancies and inflammatory and neurodegenerative disorders. However, lacking approved drugs targeting AK hinders broad studies on this enzyme's pathological importance and therapeutic potential. In this work, we determined the effect of a series of dinucleoside polyphosphate derivatives, commercially available (11 compounds) and newly synthesized (8 compounds), on the catalytic activity of human adenylate kinase isoenzyme 1 (hAK1). The tested compounds belonged to the following groups: (1) diadenosine polyphosphates with different phosphate chain lengths, (2) base-modified derivatives, and (3) phosphate-modified derivatives. We found that all the investigated compounds inhibited the catalytic activity of hAK1, yet with different efficiencies. Three dinucleoside polyphosphates showed IC values below 1 µM, and the most significant inhibitory effect was observed for P-(5'-adenosyl) P-(5'-adenosyl) pentaphosphate (ApA). To understand the observed differences in the inhibition efficiency of the tested dinucleoside polyphosphates, the molecular docking of these compounds to hAK1 was performed. Finally, we conducted a quantitative structure-activity relationship (QSAR) analysis to establish a computational prediction model for hAK1 modulators. Two PLS-regression-based models were built using kinetic data obtained from the AK1 activity analysis performed in both directions of the enzymatic reaction. Model 1 (AMP and ATP synthesis) had a good prediction power (R = 0.931, Q = 0.854, and MAE = 0.286), while Model 2 (ADP synthesis) exhibited a moderate quality (R = 0.913, Q = 0.848, and MAE = 0.370). These studies can help better understand the interactions between dinucleoside polyphosphates and adenylate kinase to attain more effective and selective inhibitors in the future.
Topics: Humans; Quantitative Structure-Activity Relationship; Dinucleoside Phosphates; Kinetics; Molecular Structure; Adenylate Kinase; Dose-Response Relationship, Drug; Protein Kinase Inhibitors; Enzyme Inhibitors
PubMed: 38744169
DOI: 10.1016/j.bioorg.2024.107432 -
Nature Communications May 2024c-di-AMP is an essential and widespread nucleotide second messenger in bacterial signaling. For most c-di-AMP synthesizing organisms, c-di-AMP homeostasis and the...
c-di-AMP is an essential and widespread nucleotide second messenger in bacterial signaling. For most c-di-AMP synthesizing organisms, c-di-AMP homeostasis and the molecular mechanisms pertaining to its signal transduction are of great concern. Here we show that c-di-AMP binds the N-acetylglucosamine (GlcNAc)-sensing regulator DasR, indicating a direct link between c-di-AMP and GlcNAc signaling. Beyond its foundational role in cell-surface structure, GlcNAc is attractive as a major nutrient and messenger molecule regulating multiple cellular processes from bacteria to humans. We show that increased c-di-AMP levels allosterically activate DasR as a master repressor of GlcNAc utilization, causing the shutdown of the DasR-mediated GlcNAc signaling cascade and leading to a consistent enhancement in the developmental transition and antibiotic production in Saccharopolyspora erythraea. The expression of disA, encoding diadenylate cyclase, is directly repressed by the regulator DasR in response to GlcNAc signaling, thus forming a self-sustaining transcriptional feedback loop for c-di-AMP synthesis. These findings shed light on the allosteric regulation by c-di-AMP, which appears to play a prominent role in global signal integration and c-di-AMP homeostasis in bacteria and is likely widespread in streptomycetes that produce c-di-AMP.
Topics: Acetylglucosamine; Allosteric Regulation; Signal Transduction; Bacterial Proteins; Gene Expression Regulation, Bacterial; Dinucleoside Phosphates; Saccharopolyspora
PubMed: 38714645
DOI: 10.1038/s41467-024-48063-0 -
Acta Crystallographica. Section D,... May 2024CdaA is the most widespread diadenylate cyclase in many bacterial species, including several multidrug-resistant human pathogens. The enzymatic product of CdaA, cyclic...
CdaA is the most widespread diadenylate cyclase in many bacterial species, including several multidrug-resistant human pathogens. The enzymatic product of CdaA, cyclic di-AMP, is a secondary messenger that is essential for the viability of many bacteria. Its absence in humans makes CdaA a very promising and attractive target for the development of new antibiotics. Here, the structural results are presented of a crystallographic fragment screen against CdaA from Listeria monocytogenes, a saprophytic Gram-positive bacterium and an opportunistic food-borne pathogen that can cause listeriosis in humans and animals. Two of the eight fragment molecules reported here were localized in the highly conserved ATP-binding site. These fragments could serve as potential starting points for the development of antibiotics against several CdaA-dependent bacterial species.
Topics: Listeria monocytogenes; Crystallography, X-Ray; Binding Sites; Bacterial Proteins; Models, Molecular; Dinucleoside Phosphates; Anti-Bacterial Agents; Humans; Phosphorus-Oxygen Lyases; Protein Conformation
PubMed: 38682668
DOI: 10.1107/S205979832400336X -
Journal of the American Chemical Society Apr 2024Nonenzymatic template-directed RNA copying requires catalysis by divalent metal ions. The primer extension reaction involves the attack of the primer 3'-hydroxyl on the...
Nonenzymatic template-directed RNA copying requires catalysis by divalent metal ions. The primer extension reaction involves the attack of the primer 3'-hydroxyl on the adjacent phosphate of a 5'-5'-imidazolium-bridged dinucleotide substrate. However, the nature of the interaction of the catalytic metal ion with the reaction center remains unclear. To explore the coordination of the catalytic metal ion with the imidazolium-bridged dinucleotide substrate, we examined catalysis by oxophilic and thiophilic metal ions with both diastereomers of phosphorothioate-modified substrates. We show that Mg and Cd exhibit opposite preferences for the two phosphorothioate substrate diastereomers, indicating a stereospecific interaction of the divalent cation with one of the nonbridging phosphorus substituents. High-resolution X-ray crystal structures of the products of primer extension with phosphorothioate substrates reveal the absolute stereochemistry of this interaction and indicate that catalysis by Mg involves inner-sphere coordination with the nonbridging phosphate oxygen in the pro- position, while thiophilic cadmium ions interact with sulfur in the same position, as in one of the two phosphorothioate substrates. These results collectively suggest that during nonenzymatic RNA primer extension with a 5'-5'-imidazolium-bridged dinucleotide substrate the interaction of the catalytic Mg ion with the pro- oxygen of the reactive phosphate plays a crucial role in the metal-catalyzed S2(P) reaction.
Topics: RNA; Metals; Dinucleoside Phosphates; Phosphates; Catalysis; Oxygen; Ions; RNA, Catalytic
PubMed: 38579124
DOI: 10.1021/jacs.4c00323 -
International Journal of Molecular... Dec 2023To improve the chemical regulation on the activity of cyclic dinucleotides (CDNs), we here designed a reduction-responsive dithioethanol (DTE)-based dCDN prodrug...
To improve the chemical regulation on the activity of cyclic dinucleotides (CDNs), we here designed a reduction-responsive dithioethanol (DTE)-based dCDN prodrug (DTE-dCDN). Prodrug improved the cell permeability with the intracellular levels peaking in 2 h in THP-1 cells. Under the reductive substance such as GSH or DTT, prodrug could be quickly decomposed in 30 min to release the parent dCDN. In THP1-Lucia cells, prodrug also retained a high bioactivity with the EC of 0.96 μM, which was 51-, 43-, and 3-fold more than the 2',3'-cGAMP (EC = 48.6 μM), the parent compound 3',3'-c-di-dAMP (EC = 41.3 μM), and ADU-S100 (EC = 2.9 μM). The high bioactivity of prodrug was validated to be highly correlated with the activation of the STING signaling pathway. Furthermore, prodrug could also improve the transcriptional expression levels of , , and in THP-1 cells. These results will be helpful to the development of chemically controllable CDN prodrugs with a high cellular permeability and potency.
Topics: Deoxyribose; Alarmins; Dinucleoside Phosphates; Permeability; Prodrugs
PubMed: 38203256
DOI: 10.3390/ijms25010086 -
International Journal of Molecular... Nov 2023Dinucleoside polyphosphates (NpNs) are considered novel signalling molecules involved in the induction of plant defence mechanisms. However, NpN signal recognition and...
Dinucleoside polyphosphates (NpNs) are considered novel signalling molecules involved in the induction of plant defence mechanisms. However, NpN signal recognition and transduction are still enigmatic. Therefore, the aim of our research was the identification of the NpN receptor and signal transduction pathways evoked by these nucleotides. Earlier, we proved that purine and pyrimidine NpNs differentially affect the phenylpropanoid pathway in suspension-cultured cells. Here, we report, for the first time, that both diadenosine tetraphosphate (ApA) and dicytidine tetraphosphate (CpC)-induced stomatal closure in . Moreover, we showed that plasma membrane purinoreceptor P2K1/DORN1 (does not respond to nucleotide 1) is essential for ApA-induced stomata movements but not for CpC. Wild-type Col-0 and the knockout mutant were used. Examination of the leaf epidermis mutant provided evidence that P2K1/DORN1 is a part of the signal transduction pathway in stomatal closure evoked by extracellular ApA but not by CpC. Reactive oxygen species (ROS) are involved in signal transduction caused by ApA and CpC, leading to stomatal closure. ApA induced and CpC suppressed the transcriptional response in wild-type plants. Moreover, in leaves, the effect of ApA on gene expression was impaired. The interaction between P2K1/DORN1 and ApA leads to changes in the transcription of signalling hubs in signal transduction pathways.
Topics: Arabidopsis; Dinucleoside Phosphates; Signal Transduction; Cell Membrane; Receptors, Purinergic
PubMed: 38069010
DOI: 10.3390/ijms242316688 -
Biochemistry Aug 2023Adenylate kinases play a crucial role in cellular energy homeostasis through the interconversion of ATP, AMP, and ADP in all living organisms. Here, we explore how...
Adenylate kinases play a crucial role in cellular energy homeostasis through the interconversion of ATP, AMP, and ADP in all living organisms. Here, we explore how adenylate kinase (AdK) from interacts with diadenosine tetraphosphate (AP4A), a putative alarmone associated with transcriptional regulation, stress, and DNA damage response. From a combination of EPR and NMR spectroscopy together with X-ray crystallography, we found that AdK interacts with AP4A with two distinct modes that occur on disparate time scales. First, AdK dynamically interconverts between open and closed states with equal weights in the presence of AP4A. On a much slower time scale, AdK hydrolyses AP4A, and we suggest that the dynamically accessed substrate-bound open AdK conformation enables this hydrolytic activity. The partitioning of the enzyme into open and closed states is discussed in relation to a recently proposed linkage between active site dynamics and collective conformational dynamics.
Topics: Escherichia coli; Adenylate Kinase; Hydrolysis; Dinucleoside Phosphates; Catalysis; Catalytic Domain
PubMed: 37418448
DOI: 10.1021/acs.biochem.3c00189 -
Nature Communications Jun 2023Cyclic di-AMP is the only known essential second messenger in bacteria and archaea, regulating different proteins indispensable for numerous physiological processes. In...
Cyclic di-AMP is the only known essential second messenger in bacteria and archaea, regulating different proteins indispensable for numerous physiological processes. In particular, it controls various potassium and osmolyte transporters involved in osmoregulation. In Bacillus subtilis, the K/H symporter KimA of the KUP family is inactivated by c-di-AMP. KimA sustains survival at potassium limitation at low external pH by mediating potassium ion uptake. However, at elevated intracellular K concentrations, further K accumulation would be toxic. In this study, we reveal the molecular basis of how c-di-AMP binding inhibits KimA. We report cryo-EM structures of KimA with bound c-di-AMP in detergent solution and reconstituted in amphipols. By combining structural data with functional assays and molecular dynamics simulations we reveal how c-di-AMP modulates transport. We show that an intracellular loop in the transmembrane domain interacts with c-di-AMP bound to the adjacent cytosolic domain. This reduces the mobility of transmembrane helices at the cytosolic side of the K binding site and therefore traps KimA in an inward-occluded conformation.
Topics: Cyclic AMP; Protons; Bacterial Proteins; Second Messenger Systems; Membrane Transport Proteins; Potassium; Dinucleoside Phosphates
PubMed: 37344476
DOI: 10.1038/s41467-023-38944-1 -
Nucleic Acids Research Jul 2023The nonenzymatic copying of RNA is thought to have been necessary for the transition between prebiotic chemistry and ribozyme-catalyzed RNA replication in the RNA World....
The nonenzymatic copying of RNA is thought to have been necessary for the transition between prebiotic chemistry and ribozyme-catalyzed RNA replication in the RNA World. We have previously shown that a potentially prebiotic nucleotide activation pathway based on phospho-Passerini chemistry can lead to the efficient synthesis of 2-aminoimidazole activated mononucleotides when carried out under freeze-thaw cycling conditions. Such activated nucleotides react with each other to form 5'-5' 2-aminoimidazolium bridged dinucleotides, enabling template-directed primer extension to occur within the same reaction mixture. However, mononucleotides linked to oligonucleotides by a 5'-5' 2-aminoimidazolium bridge are superior substrates for nonenzymatic primer extension; their higher intrinsic reactivity and their higher template affinity enable faster template copying at lower substrate concentrations. Here we show that eutectic phase phospho-Passerini chemistry efficiently activates short oligonucleotides and promotes the formation of monomer-bridged-oligonucleotide species during freeze-thaw cycles. We then demonstrate that in-situ generated monomer-bridged-oligonucleotides lead to efficient nonenzymatic template copying in the same reaction mixture. Our demonstration that multiple steps in the pathway from activation chemistry to RNA copying can occur together in a single complex environment simplifies this aspect of the origin of life.
Topics: RNA; Oligonucleotides; RNA, Catalytic; Nucleotides; Dinucleoside Phosphates
PubMed: 37247941
DOI: 10.1093/nar/gkad439