Aneta Kaczor1, Karolina Witek1,2,3,4,5, Sabina Podlewska1,6, Veronique Sinou3, Joanna Czekajewska2, Ewa Żesławska7, Agata Doroz-Płonka1, Annamaria Lubelska1, Gniewomir Latacz1, Wojciech Nitek8, Markus Bischoff4, Sandrine Alibert3, Jean-Marie Pagès3, Claus Jacob5, Elżbieta Karczewska2, Jean-Michel Bolla3, Jadwiga Handzlik1. 1. Department of Technology and Biotechnology of Drugs, Jagiellonian University, Medical College, ul. Medyczna 9, 30-688 Krakow, Poland. 2. Department of Pharmaceutical Microbiology, Jagiellonian University, Medical College, ul. Medyczna 9, 30-688 Krakow, Poland. 3. UMR_MD1, U-1261, Aix Marseille Univ, INSERM, SSA, MCT, Faculté de Pharmacie, 27 Bd Jean Moulin, 13005 Marseille, France. 4. Institute for Medical Microbiology and Hygiene, Saarland University, D-66421 Homburg/Saar, Germany. 5. Division of Bioorganic Chemistry, School of Pharmacy, Saarland University, Campus B 2.1, D-66123 Saarbruecken, Germany. 6. Maj Institute of Pharmacology, Polish Academy of Sciences, Department of Medicinal Chemistry, ul. Smętna 12, 31-343 Krakow, Poland. 7. Pedagogical University of Cracow, Institute of Biology, ul. Podchorążych 2, 30-084 Krakow, Poland. 8. Faculty of Chemistry, Jagiellonian University, ul. Gronostajowa 2, 30-387 Krakow, Poland.
Abstract
In the search for an effective strategy to overcome antimicrobial resistance, a series of new morpholine-containing 5-arylideneimidazolones differing within either the amine moiety or at position five of imidazolones was explored as potential antibiotic adjuvants against Gram-positive and Gram-negative bacteria. Compounds (7-23) were tested for oxacillin adjuvant properties in the Methicillin-susceptible S. aureus (MSSA) strain ATCC 25923 and Methicillin-resistant S. aureus MRSA 19449. Compounds 14-16 were tested additionally in combination with various antibiotics. Molecular modelling was performed to assess potential mechanism of action. Microdilution and real-time efflux (RTE) assays were carried out in strains of K. aerogenes to determine the potential of compounds 7-23 to block the multidrug efflux pump AcrAB-TolC. Drug-like properties were determined experimentally. Two compounds (10, 15) containing non-condensed aromatic rings, significantly reduced oxacillin MICs in MRSA 19449, while 15 additionally enhanced the effectiveness of ampicillin. Results of molecular modelling confirmed the interaction with the allosteric site of PBP2a as a probable MDR-reversing mechanism. In RTE, the compounds inhibited AcrAB-TolC even to 90% (19). The 4-phenylbenzylidene derivative (15) demonstrated significant MDR-reversal "dual action" for β-lactam antibiotics in MRSA and inhibited AcrAB-TolC in K. aerogenes. 15 displayed also satisfied solubility and safety towards CYP3A4 in vitro.
In the sclass="Chemical">earch for an effective stn class="Species">rategy to overcome antimicrobial resistance, a series of new morpholine-containing 5-arylideneimidazolones differing within either the amine moiety or at position five of imidazolones was explored as potential antibiotic adjuvants against Gram-positive and Gram-negative bacteria. Compounds (7-23) were tested for oxacillin adjuvant properties in the Methicillin-susceptible S. aureus (MSSA) strain ATCC 25923 and Methicillin-resistant S. aureus MRSA 19449. Compounds 14-16 were tested additionally in combination with various antibiotics. Molecular modelling was performed to assess potential mechanism of action. Microdilution and real-time efflux (RTE) assays were carried out in strains of K. aerogenes to determine the potential of compounds 7-23 to block the multidrug efflux pump AcrAB-TolC. Drug-like properties were determined experimentally. Two compounds (10, 15) containing non-condensed aromatic rings, significantly reduced oxacillin MICs in MRSA 19449, while 15 additionally enhanced the effectiveness of ampicillin. Results of molecular modelling confirmed the interaction with the allosteric site of PBP2a as a probable MDR-reversing mechanism. In RTE, the compounds inhibited AcrAB-TolC even to 90% (19). The 4-phenylbenzylidene derivative (15) demonstrated significant MDR-reversal "dual action" for β-lactam antibiotics in MRSA and inhibited AcrAB-TolC in K. aerogenes. 15 displayed also satisfied solubility and safety towards CYP3A4 in vitro.