Publications by authors named "Ivailo Simoff"

Here, we describe the identification of an antibiotic class acting via LpxH, a clinically unexploited target in lipopolysaccharide synthesis. The lipopolysaccharide synthesis pathway is essential in most Gram-negative bacteria and there is no analogous pathway in humans. Based on a series of phenotypic screens, we identified a hit targeting this pathway that had activity on efflux-defective strains of .

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Article Synopsis
  • A new series of benzothiazole inhibitors targeting bacterial DNA gyrase and topoisomerase IV were created, displaying strong antibacterial effects against various Gram-positive and multi-drug resistant strains.
  • The best compounds exhibited minimal inhibitory concentrations (MICs) between <0.03125-0.25 μg/mL for Gram-positive bacteria and 1-4 μg/mL for Gram-negative bacteria.
  • One lead compound was found to have favorable properties, including good solubility, metabolic stability, and selectivity for bacterial topoisomerases, and showed effective in vivo results against vancomycin-intermediate thigh infections in a mouse model.
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We have developed compounds with a promising activity against and , which are both on the WHO priority list of antibiotic-resistant bacteria. Starting from DNA gyrase inhibitor , we identified compound , featuring a 10-fold improved aqueous solubility, a 10-fold improved inhibition of topoisomerase IV from and , a 10-fold decreased inhibition of human topoisomerase IIα, and no cross-resistance to novobiocin. Cocrystal structures of in complex with GyrB24 and ()- in complex with GyrB23 and GyrB24 revealed their binding to the ATP-binding pocket of the GyrB subunit.

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Peptide drugs and biologics provide opportunities for treatments of many diseases. However, due to their poor stability and permeability in the gastrointestinal tract, the oral bioavailability of peptide drugs is negligible. Nanoparticle formulations have been proposed to circumvent these hurdles, but systemic exposure of orally administered peptide drugs has remained elusive.

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Acamprosate is an anionic drug substance widely used in treating symptoms of alcohol withdrawal. It was recently shown that oral acamprosate absorption is likely due to paracellular transport. In contrast, little is known about the eliminating mechanism clearing acamprosate from the blood in the kidneys, despite the fact that studies have shown renal secretion of acamprosate.

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Madin-Darby canine kidney (MDCK) II cells stably transfected with transport proteins are commonly used models for drug transport studies. However, endogenous expression of especially canine MDR1 (cMDR1) confounds the interpretation of such studies. Here we have established an MDCK cell line stably overexpressing the human MDR1 transporter (hMDR1; P-glycoprotein), and used CRISPR-Cas9 gene editing to knockout the endogenous cMDR1.

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Madin-Darby canine kidney II cells transfected with one or several transport proteins are commonly used models to study drug transport. In these cells, however, endogenous transporters such as canine Mdr1/P-glycoprotein (Abcb1) complicate the interpretation of transport studies. The aim of this investigation was to establish a Madin-Darby canine kidney II cell line using CRISPR-Cas9 gene-editing technology to knock out endogenous canine Mdr1 (cMdr1) expression.

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In this study we provide general information on the little studied eukaryotic ribosomal protein rpL15. Saccharomyces cerevisiae has two genes, YRPL15A and YRPL15B that could potentially code for yeast rpL15 (YrpL15). YRPL15A is essential while YRPL15B is dispensable.

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The aim of this study was to analyze the functional importance of the C-terminus of the essential yeast ribosomal protein L5 (YrpL5). Previous studies have indicated that the C-terminal region of YrpL5 forms an alpha-helix with a positively charged surface that is involved in protein-5S rRNA interaction. Formation of an YrpL5.

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