Gallium(iii) and iron(iii) complexes of quinolone antimicrobials.
Iron is an essential nutrient for many microbes. According to the "Trojan Horse Hypothesis", biological systems have difficulties distinguishing between Fe(3+) and Ga(3+), which constitutes the antimicrobial efficacy of the gallium(iii) ion. Nine novel tris(quinolono)gallium(iii) complexes and their corresponding iron(iii) analogs have been synthesized and fully characterized. Quinolone antimicrobial agents from three drug generations were used in this study: ciprofloxacin, enoxacin, fleroxacin, levofloxacin, lomefloxacin, nalidixic acid, norfloxacin, oxolinic acid, and pipemidic acid. The antimicrobial efficacy of the tris(quinolono)gallium(iii) complexes was studied against E. faecalis and S. aureus (both Gram-positive), as well as E. coli, K. pneumonia, and P. aeruginosa (all Gram-negative) in direct comparison to the tris(quinolono)iron(iii) complexes and the corresponding free quinolone ligands at various concentrations. For the tris(quinolono)gallium(iii) complexes, no combinational antimicrobial effects between Ga(3+) and the quinolone antimicrobial agents were observed.
Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada. orvig@chem.ubc.ca.
Katja Dralle
KD
Mjos
Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada. orvig@chem.ubc.ca.
Jacqueline F
JF
Cawthray
Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada. orvig@chem.ubc.ca.
Elena
E
Polishchuk
Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada. orvig@chem.ubc.ca.
Michael J
MJ
Abrams
Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada. orvig@chem.ubc.ca.
Chris
C
Orvig
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects / Q000254:growth & development; D056831:Coordination Complexes / Q000737:chemistry / Q000494:pharmacology; D005708:Gallium / Q000737:chemistry / Q000494:pharmacology; D007501:Iron / Q000737:chemistry / Q000494:pharmacology; D015363:Quinolones / Q000737:chemistry / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D056831:Coordination Complexes; D015363:Quinolones; D005708:Gallium; D007501:Iron