The nucleoside/nucleotide derived antiviral agents have been the most important components of antiviral therapy used in clinics. Recently, the focus of the medicinal chemists within this exciting research field has been affected mainly by the lack of effective therapies for the Hepatitis C virus (HCV) infection and several other "neglected" diseases caused by viruses such as Zika or Dengue. 2'-Methyl modified nucleosides and their monophosphate prodrugs (ProTides) have revolutionized the therapies for HCV in the last few years and, according to the latest research efforts, have also brought a promise for treatment of diseases caused by other members of Flaviviridae family. Here, we report on the design and synthesis of 5'-N and S modified ProTides derived from 2'-methyladenosine. We studied potential applicability of these derivatives as prodrugs of this archetypal antiviral compound.
- MeSH
- adenosin analogy a deriváty chemie MeSH
- antivirové látky chemická syntéza chemie farmakologie MeSH
- dusík chemie MeSH
- Hepacivirus účinky léků MeSH
- lidé MeSH
- magnetická rezonanční spektroskopie MeSH
- nukleotidy chemie metabolismus farmakologie MeSH
- prekurzory léčiv chemická syntéza chemie farmakologie MeSH
- síra chemie MeSH
- virus dengue účinky léků MeSH
- virus zika účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Successful surgeries involving orthopedic implants depend on the avoidance of biofilm development on the implant surface during the early postoperative period. Here, we investigate the potential of novel antibacterial compounds-second-generation lipophosphonoxins (LPPOs II)-as additives to surgical bone cements. We demonstrate (i) excellent thermostability of LPPOs II, which is essential to withstand elevated temperatures during exothermic cement polymerization; (ii) unchanged tensile strength and elongation at the break properties of the composite cements containing LPPOs II compared to cements without additives; (iii) convenient elution kinetics on the order of days; and (iv) the strong antibiofilm activity of the LPPO II-loaded cements even against bacteria resistant to the medicinally utilized antibiotic, gentamicin. Thus, LPPOs II display promising potential as antimicrobial additives to surgical bone cements.
- Klíčová slova
- lipofosfonoxiny,
- MeSH
- antiinfekční látky * analýza terapeutické užití MeSH
- biofilmy MeSH
- grampozitivní bakterie MeSH
- hydrofobní a hydrofilní interakce MeSH
- iminosacharidy analýza terapeutické užití MeSH
- infekce spojené s protézou prevence a kontrola MeSH
- kostní cementy * analýza terapeutické užití MeSH
- lidé MeSH
- mikrobiální testy citlivosti metody MeSH
- nukleosidy analýza terapeutické užití MeSH
- organofosfonáty analýza terapeutické užití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
Nucleotides, nucleosides and their derivatives are present in all cells at varying concentrations that change with the nutritional, and energetic status of the cell. Precise measurement of the concentrations of these molecules is instrumental for understanding their regulatory effects. Such measurement is challenging due to the inherent instability of these molecules and, despite many decades of research, the reported values differ widely. Here, we present a comprehensive and easy-to-use approach for determination of the intracellular concentrations of >25 target molecular species. The approach uses rapid filtration and cold acidic extraction followed by high performance liquid chromatography (HPLC) in the hydrophilic interaction liquid chromatography (HILIC) mode using zwitterionic columns coupled with UV and MS detectors. The method reliably detects and quantifies all the analytes expected to be observed in the bacterial cell and paves the way for future studies correlating their concentrations with biological effects.
Plasmodium falciparum (Pf) and Plasmodium vivax (Pv) are the foremost causative agents of malaria. Due to the development of resistance to current antimalarial medications, new drugs for this parasitic disease need to be discovered. The activity of hypoxanthine-guanine-[xanthine]-phosphoribosyltransferase, HG[X]PRT, is reported to be essential for the growth of both of these parasites, making it an excellent target for antimalarial drug discovery. Here, we have used rational structure-based methods to design an inhibitor, [3R,4R]-4-guanin-9-yl-3-((S)-2-hydroxy-2-phosphonoethyl)oxy-1-N-(phosphonopropionyl)pyrrolidine, of PvHGPRT and PfHGXPRT that has Ki values of 8 and 7 nM, respectively, for these two enzymes. The crystal structure of PvHGPRT in complex with this compound has been determined to 2.85 Å resolution. The corresponding complex with human HGPRT was also obtained to allow a direct comparison of the binding modes of this compound with the two enzymes. The tetra-(ethyl l-phenylalanine) tetraamide prodrug of this compound was synthesized, and it has an IC50 of 11.7 ± 3.2 μM against Pf lines grown in culture and a CC50 in human A549 cell lines of 102 ± 11 μM, thus giving it a ∼10-fold selectivity index.
- MeSH
- antimalarika chemie farmakologie MeSH
- bisfosfonáty chemie farmakologie MeSH
- hypoxanthinfosforibosyltransferasa antagonisté a inhibitory chemie metabolismus MeSH
- katalytická doména MeSH
- konformace proteinů MeSH
- krystalografie rentgenová MeSH
- lidé MeSH
- molekulární modely MeSH
- pentosyltransferasy antagonisté a inhibitory chemie metabolismus MeSH
- Plasmodium vivax enzymologie MeSH
- proteiny z Escherichia coli chemie MeSH
- racionální návrh léčiv MeSH
- techniky syntetické chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The alarmone (p)ppGpp plays pivotal roles in basic bacterial stress responses by increasing tolerance of various nutritional limitations and chemical insults, including antibiotics. Despite intensive studies since (p)ppGpp was discovered over 4 decades ago, (p)ppGpp binding proteins have not been systematically identified in Escherichia coli We applied DRaCALA (differential radial capillary action of ligand assay) to identify (p)ppGpp-protein interactions. We discovered 12 new (p)ppGpp targets in E. coli that, based on their physiological functions, could be classified into four major groups, involved in (i) purine nucleotide homeostasis (YgdH), (ii) ribosome biogenesis and translation (RsgA, Era, HflX, and LepA), (iii) maturation of dehydrogenases (HypB), and (iv) metabolism of (p)ppGpp (MutT, NudG, TrmE, NadR, PhoA, and UshA). We present a comprehensive and comparative biochemical and physiological characterization of these novel (p)ppGpp targets together with a comparative analysis of relevant, known (p)ppGpp binding proteins. Via this, primary targets of (p)ppGpp in E. coli are identified. The GTP salvage biosynthesis pathway and ribosome biogenesis and translation are confirmed as targets of (p)ppGpp that are highly conserved between E. coli and Firmicutes In addition, an alternative (p)ppGpp degradative pathway, involving NudG and MutT, was uncovered. This report thus significantly expands the known cohort of (p)ppGpp targets in E. coliIMPORTANCE Antibiotic resistance and tolerance exhibited by pathogenic bacteria have resulted in a global public health crisis. Remarkably, almost all bacterial pathogens require the alarmone (p)ppGpp to be virulent. Thus, (p)ppGpp not only induces tolerance of nutritional limitations and chemical insults, including antibiotics, but is also often required for induction of virulence genes. However, understanding of the molecular targets of (p)ppGpp and the mechanisms by which (p)ppGpp influences bacterial physiology is incomplete. In this study, a systematic approach was used to uncover novel targets of (p)ppGpp in E. coli, the best-studied model bacterium. Comprehensive comparative studies of the targets revealed conserved target pathways of (p)ppGpp in both Gram-positive and -negative bacteria and novel targets of (p)ppGpp, including an alternative degradative pathway of (p)ppGpp. Thus, our discoveries may help in understanding of how (p)ppGpp increases the stress resilience and multidrug tolerance not only of the model organism E. coli but also of the pathogenic organisms in which these targets are conserved.
We describe the expression and purification of an active recombinant Zika virus RNA-dependent RNA polymerase (RdRp). Next, we present the development and optimization of an in vitro assay to measure its activity. We then applied the assay to selected triphosphate analogs and discovered that 2'-C-methylated nucleosides exhibit strong inhibitory activity. Surprisingly, also carbocyclic derivatives with the carbohydrate locked in a North-like conformation as well as a ribonucleotide with a South conformation exhibited strong activity. Our results suggest that the traditional 2'-C-methylated nucleosides pursued in the race for anti-HCV treatment can be superseded by brand new scaffolds in the case of the Zika virus.
- MeSH
- adenosintrifosfát analogy a deriváty chemie MeSH
- antivirové látky farmakologie MeSH
- inhibitory enzymů farmakologie MeSH
- lidé MeSH
- molekulární konformace MeSH
- nukleosidy chemie farmakologie MeSH
- objevování léků MeSH
- RNA-dependentní RNA-polymerasa antagonisté a inhibitory genetika izolace a purifikace MeSH
- virus zika účinky léků enzymologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The increase in the number of bacterial strains resistant to known antibiotics is alarming. In this study we report the synthesis of novel compounds termed Lipophosphonoxins II (LPPO II). We show that LPPO II display excellent activities against Gram-positive and -negative bacteria, including pathogens and multiresistant strains. We describe their mechanism of action-plasmatic membrane pore-forming activity selective for bacteria. Importantly, LPPO II neither damage nor cross the eukaryotic plasmatic membrane at their bactericidal concentrations. Further, we demonstrate LPPO II have low propensity for resistance development, likely due to their rapid membrane-targeting mode of action. Finally, we reveal that LPPO II are not toxic to either eukaryotic cells or model animals when administered orally or topically. Collectively, these results suggest that LPPO II are highly promising compounds for development into pharmaceuticals.
- MeSH
- antibakteriální látky chemická syntéza chemie farmakologie MeSH
- apoptóza účinky léků MeSH
- buněčná membrána metabolismus MeSH
- buněčné linie MeSH
- fosfolipidy chemie MeSH
- gramnegativní bakterie účinky léků MeSH
- grampozitivní bakterie účinky léků MeSH
- králíci MeSH
- lidé MeSH
- lipidové dvojvrstvy chemie MeSH
- mikrobiální testy citlivosti MeSH
- mnohočetná bakteriální léková rezistence MeSH
- myši inbrední ICR MeSH
- nádorové buněčné linie MeSH
- pyrazoly chemická syntéza chemie farmakologie MeSH
- racionální návrh léčiv MeSH
- stereoizomerie MeSH
- testy kožní dráždivosti MeSH
- uridinmonofosfát analogy a deriváty chemická syntéza chemie farmakologie MeSH
- viabilita buněk účinky léků MeSH
- vztahy mezi strukturou a aktivitou MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The advantages offered by established antibiotics in the treatment of infectious diseases are endangered due to the increase in the number of antibiotic-resistant bacterial strains. This leads to a need for new antibacterial compounds. Recently, we discovered a series of compounds termed lipophosphonoxins (LPPOs) that exhibit selective cytotoxicity towards Gram-positive bacteria that include pathogens and resistant strains. For further development of these compounds, it was necessary to identify the mechanism of their action and characterize their interaction with eukaryotic cells/organisms in more detail. Here, we show that at their bactericidal concentrations LPPOs localize to the plasmatic membrane in bacteria but not in eukaryotes. In an in vitro system we demonstrate that LPPOs create pores in the membrane. This provides an explanation of their action in vivo where they cause serious damage of the cellular membrane, efflux of the cytosol, and cell disintegration. Further, we show that (i) LPPOs are not genotoxic as determined by the Ames test, (ii) do not cross a monolayer of Caco-2 cells, suggesting they are unable of transepithelial transport, (iii) are well tolerated by living mice when administered orally but not peritoneally, and (iv) are stable at low pH, indicating they could survive the acidic environment in the stomach. Finally, using one of the most potent LPPOs, we attempted and failed to select resistant strains against this compound while we were able to readily select resistant strains against a known antibiotic, rifampicin. In summary, LPPOs represent a new class of compounds with a potential for development as antibacterial agents for topical applications and perhaps also for treatment of gastrointestinal infections.
- MeSH
- aktivní transport MeSH
- antibakteriální látky chemie farmakokinetika farmakologie MeSH
- Bacillus subtilis účinky léků růst a vývoj metabolismus MeSH
- buněčná membrána účinky léků metabolismus MeSH
- Caco-2 buňky MeSH
- Enterococcus faecalis účinky léků růst a vývoj MeSH
- grampozitivní bakterie účinky léků metabolismus MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- molekulární struktura MeSH
- myši inbrední ICR MeSH
- myši MeSH
- objevování léků MeSH
- permeabilita buněčné membrány účinky léků MeSH
- pyrimidinové nukleosidy chemie farmakokinetika farmakologie MeSH
- stabilita léku MeSH
- Streptococcus agalactiae účinky léků růst a vývoj MeSH
- transmisní elektronová mikroskopie MeSH
- vazba proteinů MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The non-hydrolyzable alkylcarbonate analogs of O-acetyl-ADP-ribose have been synthesized from the phosphorylated ribose derivatives after coupling with AMP morpholidate promoted by mechanical grinding. The analogs were assessed for their ability to inhibit the human sirtuin homolog SIRT1.
- MeSH
- inhibitory enzymů chemická syntéza chemie farmakologie MeSH
- lidé MeSH
- molekulární konformace MeSH
- O-acetyl-ADP-ribosa analogy a deriváty chemická syntéza chemie farmakologie MeSH
- sirtuin 1 antagonisté a inhibitory metabolismus MeSH
- uhličitany chemie MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
To determine the influence of internucleotide linkage and sugar ring conformation, and the role of 5'-terminal phosphate, on the activation of human RNase L, a series of 2'- and 5'-O-methylphosphonate-modified tetramers were synthesized from appropriate monomeric units and evaluated for their ability to activate human RNase L. Tetramers pAAAp(c)X modified by ribo, arabino or xylo 5'-phosphonate unit p(c)X activated RNase L with efficiency comparable to that of natural activator. Moreover, incorporation of phosphonate linkages ensured the stability against cleavage by nucleases. The substitution of 5'-terminal phosphate for 5'-terminal phosphonate in tetramer p(c)XAAA afforded tetramers with excellent activation efficiency and with complete stability against cleavage by phosphomonoesterases.
- MeSH
- adeninnukleotidy chemie MeSH
- bezbuněčný systém MeSH
- časové faktory MeSH
- chemické modely MeSH
- chemie farmaceutická metody MeSH
- dimerizace MeSH
- endoribonukleasy chemie MeSH
- kyseliny fosforité chemie MeSH
- lidé MeSH
- myši MeSH
- oligoribonukleotidy chemie MeSH
- racionální návrh léčiv MeSH
- rezonanční přenos fluorescenční energie metody MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
