| 1. |
- Chorell, Erik, 1980-, et al.
(författare)
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Design and synthesis of fluorescently labeled pilicides and curlicides: bioactive tools to study bacterial virulence mechanisms
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Pilicides and curlicides block formation of the E. coli virulence factors pili and curli. To facilitate studies of the interaction between these compounds and the pili and curli assembly systems, fluorescent pilicides and curlicides have been synthesized. This was achieved using a strategy where key pilicide and curlicide substituents were replaced by fluorophores having similar physicochemical properties. The resulting fluorescent compounds had improved anti-virulence activities as measured in pili- and curli-dependent biofilm assays. We created fluorescent pilicides and curlicides by introducing both coumarin and 4,4-Difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) fluorophores at two positions on the peptidomimetic pilicide and curlicide scaffold. Fluorescence images of the uropathogenic Escherichia coli (UPEC) strain UTI89 grown in the presence of these compounds shows that the compounds are strongly associated to the bacteria and seem to discriminate between different bacteria in a population.
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| 2. |
- Cegelski, Lynette, et al.
(författare)
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Small-molecule inhibitors target Escherichia coli amyloid biogenesis and biofilm formation
- 2009
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Ingår i: Nature Chemical Biology. - : Nature Publishing Group. - 1552-4450 .- 1552-4469. ; 5:12, s. 913-919
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Tidskriftsartikel (refereegranskat)abstract
- Curli are functional extracellular amyloid fibers produced by uropathogenic Escherichia coli (UPEC) and other Enterobacteriaceae. Ring-fused 2-pyridones, such as FN075 and BibC6, inhibited curli biogenesis in UPEC and prevented the in vitro polymerization of the major curli subunit protein CsgA. The curlicides FN075 and BibC6 share a common chemical lineage with other ring-fused 2-pyridones termed pilicides. Pilicides inhibit the assembly of type1pili, which are required for pathogenesis during urinary tract infection. Notably, the curlicides retained pilicide activities and inhibited both curli-dependent and type 1–dependent biofilms. Furthermore, pretreatment of UPEC with FN075 significantly attenuated virulence in a mouse model of urinary tract infection. Curli and type 1pili exhibited exclusive and independent roles in promoting UPEC biofilms, and curli provided a fitness advantage in vivo. Thus, the ability of FN075 to block the biogenesis of both curli and type 1pili endows unique anti-biofilm and anti-virulence activities on these compounds.
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| 3. |
- Chermenina, Maria, 1978-, et al.
(författare)
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A novel animal model for Parkinson's disease based on in vivo effects of small-molecule of alpha-synuclein
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Amyloid fibrils of alpha-synuclein are major constituents of Lewy bodies, the pathological hallmark of Parkinson’s disease. Monomeric α-synuclein is involved in synaptic vesicle trafficking and long-term maintenance of neurons. The underlying mechanisms of Parkinson’s disease are not known but it has been proposed that oligomers of α-synuclein, formed during the aggregation process, are toxic to neurons. To search for a new animal model of Parkinson’s disease, here we capitalized on the in vitro discovery of a small-molecule templator of α-synuclein fibrillization, the 2-pyridone, FN075. FN075 and MS382, another 2-pyridone variant that act as an inhibitor of amyloids in vitro, were injected into the striatum or substantia nigra of normal C57Bl/6 mice. No acute toxicity of the compounds was detected, as there was 100 % survival of the injected mice. At 6 months after the striatal injection, sensorimotor functions were impaired with no reduction in TH-positive neurons in the substantia nigra in mice injected with FN075, whereas mice injected with MS382 or vehicle had no dysfunctions. Injection of FN075 into the substantia nigra revealed a significant loss of TH-positive neurons already at 3 months and TH-negative inclusion-like structures were detected in substantia nigra neurons of these mice. Thus, the results suggest that injection of a templator of α-synuclein aggregation into the brain of normal mice can serve as a novel experimental design for an animal model of Parkinson’s disease.
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| 4. |
- Chorell, Erik, 1980-, et al.
(författare)
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Design and synthesis of C-2 substituted Thiazolo and Dihydrothiazolo ring-fused 2-Pyridones : pilicides with increased antivirulence activity
- 2010
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Ingår i: Journal of Medicinal Chemistry. - Washington, USA : American Chemical Society. - 0022-2623 .- 1520-4804. ; 53:15, s. 5690-5695
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Tidskriftsartikel (refereegranskat)abstract
- Pilicides block pili formation by binding to pilus chaperones and blocking their function in the chaperone/usher pathway in E. coli. Various C-2 substituents were introduced on the pilicide scaffold by design and synthetic method developments. Experimental evaluation showed that proper substitution of this position affected the biological activity of the compound. Aryl substituents resulted in pilicides with significantly increased potencies as measured in pili-dependent biofilm and hemagglutination assays. The structural basis of the PapD chaperone-pilicide interactions was determined by X-ray crystallography.
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| 5. |
- Chorell, Erik, 1980-, et al.
(författare)
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Diverse functionalization of Thiazolo ring-fused 2-Pyridones
- 2007
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Ingår i: Journal of Organic Chemistry. - Washington, DC 20036, USA : American Chemical Society. - 0022-3263 .- 1520-6904. ; 72:13, s. 4917-4924
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Tidskriftsartikel (refereegranskat)abstract
- Thiazolo ring-fused 2-pyridones have proven to be highly interesting scaffolds for the development of biologically active compounds. Many methods are today available to introduce a variety of substituents in the 2-pyridone part of the heterocycle. Herein we disclose how a diverse set of substituents can be introduced in the thiazolo ring, with possibilities to vary also the spatial arrangement of the substituents. A key intermediate is the oxidized framework 9 for which an effective synthesis is described. The thiazolo part of this system can be substituted either via conjugate additions, resulting in trans selectivity, or via microwave-assisted Heck couplings that result in unsaturated aryl-substituted analogues. The scaffold can also be lithiated followed by the addition of various electrophiles, which increases the diversification potential substantially, as exemplified with the introduction of halogens, alkyl, acyl, and amide substituents.
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| 6. |
- Chorell, Erik, 1980-, et al.
(författare)
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Improved procedure for the enantioselective synthesis of dihydrooxazolo and dihydrothiazolo ring-fused 2-pyridones
- 2010
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Ingår i: Tetrahedron Letters. - : Elsevier Ltd. - 0040-4039 .- 1359-8562. ; 51:18, s. 2461-2463
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Tidskriftsartikel (refereegranskat)abstract
- Improved procedures to synthesize enantioselectively analogues of a peptidomimetic scaffold with high biological relevance have been developed. Experimental design led to a general method for the preparation of dihydrooxazolo ring-fused 2-pyridones in good yields and high enantiomeric purity. The knowledge gained from this was also used to improve the microwave-accelerated synthesis of dihydrothiazolo ring-fused 2-pyridones to give complete stereo retention and high yields.
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| 7. |
- Chorell, Erik, 1980-
(författare)
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Pilicides and Curlicides : Design, synthesis, and evaluation of novel antibacterial agents targeting bacterial virulence
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- New strategies are needed to counter the growing problem of bacterial resistance to antibiotics. One such strategy is to design compounds that target bacterial virulence, which could work separately or in concert with conventional bacteriostatic or bactericidal antibiotics. Pilicides are a class of compounds based on a ring-fused 2-pyridone scaffold that target bacterial virulence by blocking the chaperone/usher pathway in E. coli and thereby inhibit the assembly of pili. This thesis describes the design, synthesis, and biological evaluation of compounds based on the pilicide scaffold with the goal of improving the pilicides and expanding their utility. Synthetic pathways have been developed to enable the introduction of substituents at the C-2 position of the pilicide scaffold. Biological evaluation of these compounds demonstrated that some C-2 substituents give rise to significant increases in potency. X-ray crystallography was used to elucidate the structural basis of this improved biological activity. Furthermore, improved methods for the preparation of oxygen-analogues and C-7 substituted derivatives of the pilicide scaffold have been developed. These new methods were used in combination with existing strategies to decorate the pilicide scaffold as part of a multivariate design approach to improve the pilicides and generate structure activity relationships (SARs). Fluorescent pilicides were prepared using a strategy where selected substituents were replaced with fluorophores having similar physicochemical properties as the original substituents. Many of the synthesized fluorescent compounds displayed potent pilicide activities and can thus be used to study the complex interactions between pilicide and bacteria. For example, when E. coli was treated with fluorescent pilicides, it was found that the compounds were not uniformly distributed throughout the bacterial population, suggesting that the compounds are primarily associated to bacteria with specific properties. Finally, by studying compounds designed to inhibit the aggregation of Aβ, it was found that some compounds based on the pilicide scaffold inhibit the formation of the functional bacterial amyloid fibers known as curli; these compounds are referred to as 'curlicides'. Some of the curlicides also prevent the formation of pili and thus exhibit dual pilicide-curlicide activity. The potential utility of such 'dual-action' compounds was highlighted by a study of one of the more potent dual pilicide-curlicides in a murine UTI model were the compound was found to significantly attenuate virulence in vivo.
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| 8. |
- Good, James A. D., 1985-, et al.
(författare)
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Attenuating Listeria monocytogenes virulence by targeting the regulatory protein PrfA
- 2016
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Ingår i: Cell chemical biology. - : Elsevier BV. - 2451-9448 .- 2451-9456. ; 23:3, s. 404-414
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Tidskriftsartikel (refereegranskat)abstract
- The transcriptional activator PrfA, a member of the Crp/Fnr family, controls the expression of some key virulence factors necessary for infection by the human bacterial pathogen Listeria monocytogenes. Phenotypic screening identified ring-fused 2-pyridone molecules that at low micromolar concentrations attenuate L. monocytogenes infectivity by reducing the expression of virulence genes, without compromising bacterial growth. These inhibitors bind the transcriptional regulator PrfA and decrease its affinity for the consensus DNA binding site. Structural characterization of this interaction revealed that one of the ring-fused 2-pyridones, compound 1, binds within a hydrophobic pocket, located between the C- and N-terminal domains of PrfA, and interacts with residues important for PrfA activation. This indicates that these inhibitors maintain the DNA-binding helix-turn-helix motif of PrfA in a disordered state, thereby preventing a PrfA:DNA interaction. Ring-fused 2-pyridones represent a new class of chemical probes for studying virulence in L. monocytogenes.
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| 9. |
- Pemberton, Nils, et al.
(författare)
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Microwave-assisted synthesis and functionalization of 2-pyridones, 2-quinolones and other ring-fused 2-pyridones
- 2006
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Ingår i: Microwave-assisted synthesis of hetreocycles. - Berlin, Heidelberg : Springer-Verlag. - 9783540309833 ; , s. 1-30
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- 2-pyridones are important heterocycles with great applicability in medicinal chemistry and this core structure can be found in compounds with various biological/medicinal applications. Here we show how microwave-assisted chemistry can be used to effectively synthesize and functionalize substituted monocyclic 2-pyridones, 2-quinolones and other ring-fused 2-pyridones. The chapter covers recent advancements in this field mainly describing methods developed with instruments specially designed for microwave-assisted organic synthesis (MAOS).
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| 10. |
- Åberg, Veronica, 1976-, et al.
(författare)
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Carboxylic acid isosteres improve the activity of ring-fused 2-pyridones that inhibit pilus biogenesis in E. coli
- 2008
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Ingår i: Bioorganic & Medicinal Chemistry Letters. - : Elsevier Ltd. - 0960-894X. ; 18:12, s. 3536-3540
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Tidskriftsartikel (refereegranskat)abstract
- Ring-fused 2-pyridones, termed pilicides, are small synthetic compounds that inhibit pilus assembly in uropathogenic Escherichia coli. Their biological activity is clearly dependent upon a carboxylic acid functionality. Here, we present the synthesis and biological evaluation of carboxylic acid isosteres, including, for example, tetrazoles, acyl sulfonamides, and hydroxamic acids of two lead 2-pyridones. Two independent biological evaluations show that acyl sulfonamides and tetrazoles significantly improve pilicide activity against uropathogenic E. coli.
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