() infection causes tuberculosis (TB). TB is one of the most intractable infectious diseases, causing over 1.13 million deaths annually.
View Article and Find Full Text PDFBackground: Non-tuberculous mycobacteria (NTM) infection presents a growing global health problem and requires new antibiotics targeting enzymes that are essential for the pathogens under various metabolic conditions, with high target specificity, good solubility and with attractive combinatory potency.
Methods: SQ31f was synthesized by a simplified synthesis protocol, and its effect on growth inhibition of fast- and slow-growing NTM and clinical isolates, whole-cell ATP depletion, ex vivo macrophages and its potency in combination with other antibiotics were evaluated. Molecular docking studies were employed to assess SQ31f's binding mode.
Priority 1: critical WHO pathogen Acinetobacter baumannii depends on ATP synthesis and ATP:ADP homeostasis and its bifunctional FF-ATP synthase. While synthesizing ATP, it regulates ATP cleavage by its inhibitory ε subunit to prevent wasteful ATP consumption. We determined cryo-electron microscopy structures of the ATPase active A.
View Article and Find Full Text PDFThe FF-ATP synthase engine is essential for viability and growth of nontuberculous mycobacteria (NTM) by providing the biological energy ATP and keeping ATP homeostasis under hypoxic stress conditions. Here, we report the discovery of the diarylquinoline TBAJ-5307 as a broad spectrum anti-NTM inhibitor, targeting the F domain of the engine and preventing rotation and proton translocation. TBAJ-5307 is active at low nanomolar concentrations against fast- and slow-growing NTM as well as clinical isolates by depleting intrabacterial ATP.
View Article and Find Full Text PDFNew drugs are needed to combat multidrug-resistant tuberculosis. The electron transport chain (ETC) maintains the electrochemical potential across the cytoplasmic membrane and allows the production of ATP, the energy currency of any living cell. The mycobacterial engine F-ATP synthase catalyzes the formation of ATP and has come into focus as an attractive and rich drug target.
View Article and Find Full Text PDFIntroduction: Tuberculosis (TB), caused by (Mtb), is the most devastating bacterial disease. Multidrug-resistant Mtb strains are spreading worldwide, underscoring the need for new anti-TB targets and inhibitors. The respiratory chain complexes, including the cytochrome oxidase (cyt-), have been identified as an attractive target for drug development.
View Article and Find Full Text PDFThe Acinetobacter baumannii F F -ATP synthase (α :β :γ:δ:ε:a:b :c ), which is essential for this strictly respiratory opportunistic human pathogen, is incapable of ATP-driven proton translocation due to its latent ATPase activity. Here, we generated and purified the first recombinant A. baumannii F -ATPase (AbF -ATPase) composed of subunits α :β :γ:ε, showing latent ATP hydrolysis.
View Article and Find Full Text PDFBiochem Biophys Res Commun
September 2023
The cases of lung disease caused by non-tuberculous mycobacterium Mycobacterium abscessus (Mab) are increasing and not reliably curable. Repurposing of anti-tuberculosis inhibitors brought the oxidative phosphorylation pathway with its final product ATP, formed by the essential FF-ATP synthase (subunits α:β:γ:δ:ε:a:b:b':c), into focus as an attractive inhibitor target against Mab. Because of the pharmacological attractiveness of this enzyme, we generated and purified a recombinant and enzymatically active Mab F-ATPase complex, including subunits α:β:γ:δ:ε (MabF-αβγδε) to achieve mechanistic, regulatory, and structural insights.
View Article and Find Full Text PDFThe architectural chromatin factor high-mobility group AT-hook 2 (HMGA2) is causally involved in several human malignancies and pathologies. HMGA2 is not expressed in most normal adult somatic cells, which renders the protein an attractive drug target. An established cell-based compound library screen identified the fibroblast growth factor receptor (FGFR) inhibitor PD173074 as an antagonist of HMGA2-mediated transcriptional reporter gene activation.
View Article and Find Full Text PDFThe mycobacterial cytochrome complex deserves the name "supercomplex" since it combines three cytochrome oxidases-cytochrome , cytochrome , and cytochrome -into one supramolecular machine and performs electron transfer for the reduction of oxygen to water and proton transport to generate the proton motive force for ATP synthesis. Thus, the complex represents a valid drug target for Mycobacterium tuberculosis infections. The production and purification of an entire M.
View Article and Find Full Text PDFThe FF-ATP synthase is required for the viability of tuberculosis (TB) and nontuberculous mycobacteria (NTM) and has been validated as a drug target. Here, we present the cryo-EM structures of the Mycobacterium smegmatis F-ATPase and the FF-ATP synthase with different nucleotide occupation within the catalytic sites and visualize critical elements for latent ATP hydrolysis and efficient ATP synthesis. Mutational studies reveal that the extended C-terminal domain (αCTD) of subunit α is the main element for the self-inhibition mechanism of ATP hydrolysis for TB and NTM bacteria.
View Article and Find Full Text PDFTuberculosis (TB) remains a leading cause of infectious disease-related mortality and morbidity. Pyrazinamide (PZA) is a critical component of the first-line TB treatment regimen because of its sterilizing activity against non-replicating Mycobacterium tuberculosis (Mtb), but its mechanism of action has remained enigmatic. PZA is a prodrug converted by pyrazinamidase encoded by pncA within Mtb to the active moiety, pyrazinoic acid (POA) and PZA resistance is caused by loss-of-function mutations to pyrazinamidase.
View Article and Find Full Text PDFCurr Res Struct Biol
September 2022
Tuberculosis (TB), the deadly disease caused by (), kills more people worldwide than any other bacterial infectious disease. There has been a recent resurgence of TB drug discovery activities, resulting in the identification of a number of novel enzyme inhibitors. Many of these inhibitors target the electron transport chain complexes and the FF-ATP synthase; these enzymes represent new target spaces for drug discovery, since the generation of ATP is essential for the bacterial pathogen's physiology, persistence, and pathogenicity.
View Article and Find Full Text PDFBackground: OctaplasLG is a frozen solvent/detergent-treated plasma product used for treating complex coagulation factor deficiencies or as substitution therapy in emergency situations where specific factor concentrates are not available. A new freeze-dried (also known as lyophilized) form of OctaplasLG, referred as OctaplasLG Lyo (Octapharma AG, Switzerland) offers rapid reconstitution and more flexible storage conditions, improving logistics and utilization. This study compared the biochemical quality of OctaplasLG Lyo with OctaplasLG and single-donor fresh frozen plasma units.
View Article and Find Full Text PDF() aspartate decarboxylase PanD is required for biosynthesis of the essential cofactor coenzyme A and targeted by the first line drug pyrazinamide (PZA). PZA is a prodrug that is converted by a bacterial amidase into its bioactive form pyrazinoic acid (POA). Employing structure-function analyses we previously identified POA-based inhibitors of PanD showing much improved inhibitory activity against the enzyme.
View Article and Find Full Text PDFMycobacterium abscessus (Mab) is a nontuberculous mycobacterium of increasing clinical relevance. The rapidly growing opportunistic pathogen is intrinsically multi-drug-resistant and causes difficult-to-cure lung disease. Adenosine triphosphate, generated by the essential F F ATP synthase, is the major energy currency of the pathogen, bringing this enzyme complex into focus for the discovery of novel antimycobacterial compounds.
View Article and Find Full Text PDFAntimicrob Agents Chemother
May 2022
New drug targets and molecules with bactericidal activity are needed against the respiratory mycobacterial pathogen Mycobacterium abscessus. Employing a lead repurposing strategy, the antituberculosis compound GaMF1 was tested against M. abscessus.
View Article and Find Full Text PDFWhile many bacteria are able to bypass the requirement for oxidative phosphorylation when grown on carbohydrates, is unable to do so. Differences of amino acid composition and structural features of the mycobacterial F-ATP synthase (α:β:γ:δ:ε::::) compared to its prokaryotic or human counterparts were recently elucidated and paved avenues for the discovery of molecules interfering with various regulative mechanisms of this essential energy converter. In this context, the mycobacterial peripheral stalk subunit δ came into focus, which displays a unique N-terminal 111-amino acid extension.
View Article and Find Full Text PDFMycobacteria regulate their energy (ATP) levels to sustain their survival even in stringent living conditions. Recent studies have shown that mycobacteria not only slow down their respiratory rate but also block ATP hydrolysis of the F-ATP synthase (α:β:γ:δ:ε::::) to maintain ATP homeostasis in situations not amenable for growth. The mycobacteria-specific α C-terminus (α533-545) has unraveled to be the major regulative of latent ATP hydrolysis.
View Article and Find Full Text PDFThe stringent response is critical for the survival of Mycobacterium tuberculosis (Mtb) under nutrient starvation. The mechanism is mediated by a GTP pyrophosphokinase known as Rel, containing N-terminal synthetase and hydrolase domains and C-terminal regulatory domains, which include the TGS domain (ThrRS, GTPase, and SpoT proteins) that has been proposed to activate the synthetase domain via interaction with deacylated tRNA. Here, we present the NMR solution structure of the Mtb Rel TGS domain (MtRel TGS), consisting of five antiparallel β-strands and one helix-loop-helix motif.
View Article and Find Full Text PDFA common strategy employed in antibacterial drug discovery is the targeting of biosynthetic processes that are essential and specific for the pathogen. Specificity in particular avoids undesirable interactions with potential enzymatic counterparts in the human host, and it ensures on-target toxicity. Synthesis of pantothenate (Vitamine B5), which is a precursor of the acyl carrier coenzyme A, is an example of such a pathway.
View Article and Find Full Text PDFCellulose is synthesized by cellulose synthases (CESAs) from the glycosyltransferase GT-2 family. In plants, the CESAs form a six-lobed rosette-shaped CESA complex (CSC). Here we report crystal structures of the catalytic domain of CESA3 (AtCESA3) in both apo and uridine diphosphate (UDP)-glucose (UDP-Glc)-bound forms.
View Article and Find Full Text PDFThe approval of bedaquiline has placed energy metabolism in the limelight as an attractive target space for tuberculosis antibiotic development. While bedaquiline inhibits the mycobacterial F F ATP synthase, small molecules targeting other components of the oxidative phosphorylation pathway have been identified. Of particular interest is Telacebec (Q203), a phase 2 drug candidate inhibitor of the cytochrome bcc:aa terminal oxidase.
View Article and Find Full Text PDFThe stringent response, regulated by the bifunctional (p)ppGpp synthetase/hydrolase Rel in mycobacteria, is critical for long-term survival of the drug-tolerant dormant state of Mycobacterium tuberculosis. During amino acid starvation, MtRel senses a drop in amino acid concentration and synthesizes the messengers pppGpp and ppGpp, collectively called (p)ppGpp. Here, we investigate the role of the regulatory 'Aspartokinase, Chorismate mutase and TyrA' (ACT) domain in MtRel.
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