Monosaccharides are added to the hydrophilic face of a self-assembled asymmetric FeII metallohelix, using CuAAC chemistry. The sixteen resulting architectures are water-stable and optically pure, and exhibit improved antiproliferative selectivity against colon cancer cells (HCT116 p53+/+ ) with respect to the non-cancerous ARPE-19 cell line. While the most selective compound is a glucose-appended enantiomer, its cellular entry is not mainly glucose transporter-mediated. Glucose conjugation nevertheless increases nuclear delivery ca 2.5-fold, and a non-destructive interaction with DNA is indicated. Addition of the glucose units affects the binding orientation of the metallohelix to naked DNA, but does not substantially alter the overall affinity. In a mouse model, the glucose conjugated compound was far better tolerated, and tumour growth delays for the parent compound (2.6 d) were improved to 4.3 d; performance as good as cisplatin but with the advantage of no weight loss in the subjects.

• Klíčová slova
• antitumor agents, glycoconjugates, metallohelices, nuclear delivery, self-assembly,
• MeSH
• glykokonjugáty chemie   MeSH
• HCT116 buňky MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací MeSH
• kovy chemie   MeSH
• lidé MeSH
• nádory patologie   MeSH
• protonová magnetická rezonanční spektroskopie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• glykokonjugáty MeSH
• kovy MeSH

A range of new water-compatible optically pure metallohelices - made by self-assembly of simple non-peptidic organic components around Fe ions - exhibit similar architecture to some natural cationic antimicrobial peptides (CAMPs) and are found to have high, structure-dependent activity against bacteria, including clinically problematic Gram-negative pathogens. A key compound is shown to freely enter rapidly dividing E. coli cells without significant membrane disruption, and localise in distinct foci near the poles. Several related observations of CAMP-like mechanisms are made via biophysical measurements, whole genome sequencing of tolerance mutants and transcriptomic analysis. These include: high selectivity for binding of G-quadruplex DNA over double stranded DNA; inhibition of both DNA gyrase and topoisomerase I in vitro; curing of a plasmid that contributes to the very high virulence of the E. coli strain used; activation of various two-component sensor/regulator and acid response pathways; and subsequent attempts by the cell to lower the net negative charge of the surface. This impact of the compound on multiple structures and pathways corresponds with our inability to isolate fully resistant mutant strains, and supports the idea that CAMP-inspired chemical scaffolds are a realistic approach for antimicrobial drug discovery, without the practical barriers to development that are associated with natural CAMPS.

• Publikační typ
• časopisecké články MeSH

Loss of a base in DNA leading to creation of an abasic (AP) site leaving a deoxyribose residue in the strand, is a frequent lesion that may occur spontaneously or under the action of various physical and chemical agents. Progress in the understanding of the chemistry and enzymology of abasic DNA largely relies upon the study of AP sites in synthetic duplexes. We report here on interactions of diastereomerically pure metallo-helical 'flexicate' complexes, bimetallic triple-stranded ferro-helicates [Fe2(NN-NN)3](4+) incorporating the common NN-NN bis(bidentate) helicand, with short DNA duplexes containing AP sites in different sequence contexts. The results show that the flexicates bind to AP sites in DNA duplexes in a shape-selective manner. They preferentially bind to AP sites flanked by purines on both sides and their binding is enhanced when a pyrimidine is placed in opposite orientation to the lesion. Notably, the Λ-enantiomer binds to all tested AP sites with higher affinity than the Δ-enantiomer. In addition, the binding of the flexicates to AP sites inhibits the activity of human AP endonuclease 1, which is as a valid anticancer drug target. Hence, this finding indicates the potential of utilizing well-defined metallo-helical complexes for cancer chemotherapy.

• MeSH
• 2-aminopurin analýza   MeSH
• amilorid analýza   MeSH
• antitumorózní látky chemie   MeSH
• denaturace nukleových kyselin MeSH
• DNA footprinting MeSH
• DNA-lyasa (apurinová nebo apyrimidinová) antagonisté a inhibitory   MeSH
• DNA chemie   MeSH
• inhibitory enzymů chemie   MeSH
• kalorimetrie MeSH
• poškození DNA * MeSH
• vazebná místa MeSH
• železnaté sloučeniny chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 2-aminopurin MeSH
• amilorid MeSH
• antitumorózní látky MeSH
• APEX1 protein, human MeSH Prohlížeč
• DNA-lyasa (apurinová nebo apyrimidinová) MeSH
• DNA MeSH
• inhibitory enzymů MeSH
• železnaté sloučeniny MeSH