Fluoroquinolone-metal complexes: A route to counteract bacterial resistance?

• Type: Article in International Scientific Journal
• Date: 2014

Authors

Maria J Feio (Author) Other; Isabel Sousa (Author) Other; Mariana Ferreira (Author) Other; Luis Cunha Silva (Author) Other; Raul G Saraiva (Author) Other; Carla Queiros (Author) Other; Jose G Alexandre (Author) Other; Vasco Claro (Author) Other; Adelia Mendes (Author) Other; Rosa Ortiz (Author) Other; Sandra Lopes (Author) Other; Ana Luisa Amaral (Author) Other; Joao Lino (Author) Other; Patricia Fernandes (Author) Other; Ana Joao Silva (Author) Other; Lisete Moutinho (Author) Other; Baltazar de Castro (Author) FCUP; Eulalia Pereira (Author) FCUP; Lourdes Perello (Author) Other; Paula Gameiro (Author) FCUP

Journal

Title: Journal of Inorganic Biochemistry

Vol. 138

Pages: 129-143

ISSN: 0162-0134

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 46 Citations

Scopus - 51 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-009-M0K

DOI: 10.1016/j.jinorgbio.2014.05.007

Abstract (EN): Microbial resistance to antibiotics is one of the biggest public health threats of the modem world. Antibiotic resistance is an area of much clinical relevance and therefore research that has the potential to identify agents that may circumvent it or treat resistant infections is paramount. Solution behavior of various fluoroquinolone (FQ) complexes with copper(II) in the presence and absence of 1,10-phenanthroline (phen) was studied in aqueous solution, by potentiometry and/or spectrophotometiy, and are herein described. The results obtained showed that under physiological conditions (micromolar concentration range and pH 7.4) only copper(II):FQ:phen ternary complexes are stable. Hence, these complexes were synthesised and characterised by means of UV-visible and IR spectroscopy, elemental analysis and single-crystal X-ray diffraction. In these complexes, the FQ acts as a bidentate ligand that coordinates the metal cation through the carbonyl and carboxyl oxygen atoms and phen coordinates through two N-atoms forming the equatorial plane of a distorted square-pyramidal geometry. The fifth position of the penta-coordinated Cu(II) centre is generally occupied axially by an oxygen atom from a water molecule or from a nitrate ion. Minimum inhibitory concentration (MIC) determinations of the complexes and comparison with free FQ in various E. coil strains indicate that the Cu-complexes are as efficient antimicrobials as the free antibiotic. Moreover, results strongly suggest that the cell intake route of both species is different supporting, therefore, the complexes' suitability as candidates for further biological testing in FQ-resistant microorganisms.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 15