title: Insights into the Mechanism of Action of Bactericidal Lipophosphonoxins.
abstract: 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.
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic.|Institute of Microbiology, Czech Academy of Sciences v.v.i., Vídeňská 1083, 142 20 Prague 4, Czech Republic.
authors.forename: Natalya
authors.initials: N
authors.lastname: Panova
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic.
authors.forename: Eva
authors.initials: E
authors.lastname: Zborníková
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic.
authors.forename: Ondřej
authors.initials: O
authors.lastname: Šimák
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic.
authors.forename: Radek
authors.initials: R
authors.lastname: Pohl
authors.affiliation: Department of Microbiology, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 3, 775 15 Olomouc, Czech Republic.
authors.forename: Milan
authors.initials: M
authors.lastname: Kolář
authors.affiliation: Department of Microbiology, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 3, 775 15 Olomouc, Czech Republic.
authors.forename: Kateřina
authors.initials: K
authors.lastname: Bogdanová
authors.affiliation: Department of Microbiology, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 3, 775 15 Olomouc, Czech Republic.
authors.forename: Renata
authors.initials: R
authors.lastname: Večeřová
authors.affiliation: Department of Genetics and Microbiology, Faculty of Science, Charles University in Prague, Viničná 5, 128 43 Prague 2, Czech Republic.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Seydlová
authors.affiliation: Department of Genetics and Microbiology, Faculty of Science, Charles University in Prague, Viničná 5, 128 43 Prague 2, Czech Republic.
authors.forename: Radovan
authors.initials: R
authors.lastname: Fišer
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic.
authors.forename: Romana
authors.initials: R
authors.lastname: Hadravová
authors.affiliation: Institute of Microbiology, Czech Academy of Sciences v.v.i., Vídeňská 1083, 142 20 Prague 4, Czech Republic.
authors.forename: Hana
authors.initials: H
authors.lastname: Šanderová
authors.affiliation: Institute of Microbiology, Czech Academy of Sciences v.v.i., Vídeňská 1083, 142 20 Prague 4, Czech Republic.
authors.forename: Dragana
authors.initials: D
authors.lastname: Vítovská
authors.affiliation: Institute of Microbiology, Czech Academy of Sciences v.v.i., Vídeňská 1083, 142 20 Prague 4, Czech Republic.
authors.forename: Michaela
authors.initials: M
authors.lastname: Šiková
authors.affiliation: TRIOS, Ltd., Zakouřilova 142, Prague 4, 149 00, Prague, Czech Republic.
authors.forename: Tomáš
authors.initials: T
authors.lastname: Látal
authors.affiliation: University of Chemistry and Technology, Technická 5, 166 28 Prague, Czech Republic.
authors.forename: Petra
authors.initials: P
authors.lastname: Lovecká
authors.affiliation: Division of Biomolecular Physics, Institute of Physics, Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 5, 121 16 Prague 2, Czech Republic.
authors.forename: Ivan
authors.initials: I
authors.lastname: Barvík
authors.affiliation: Institute of Microbiology, Czech Academy of Sciences v.v.i., Vídeňská 1083, 142 20 Prague 4, Czech Republic.
authors.forename: Libor
authors.initials: L
authors.lastname: Krásný
authors.affiliation: Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic.
authors.forename: Dominik
authors.initials: D
authors.lastname: Rejman
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D001693:Biological Transport, Active; D018938:Caco-2 Cells; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D002463:Cell Membrane Permeability / Q000187:drug effects; D055808:Drug Discovery; D004355:Drug Stability; D013293:Enterococcus faecalis / Q000187:drug effects / Q000254:growth & development; D005260:Female; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D008826:Microbial Sensitivity Tests; D046529:Microscopy, Electron, Transmission; D015394:Molecular Structure; D011485:Protein Binding; D011741:Pyrimidine Nucleosides / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology*; D013292:Streptococcus agalactiae / Q000187:drug effects / Q000254:growth & development
chemical_list: D000900:Anti-Bacterial Agents; D011741:Pyrimidine Nucleosides