Relevance of ionic effects on norfloxacin uptake by escherichia coli

Valisena, S; Palumbo, Manlio; Parolin, Cristina; Palù, Giorgio; Meloni, G. A.

doi:10.1016/0006-2952(90)90540-2

Cited by 19 publications

(17 citation statements)

References 25 publications

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“…Maximum levels of most quinolones were reached in less than 5 min. Accumulation was proportional to the external quinolone concentration between 2 and 50 ,ug/ml (data not shown), confirming published reports that uptake occurs by simple diffusion (3,29,46). Subsequently, a 10-,ug/ml quinolone concentration was used throughout the study.…”

Section: Methodssupporting

confidence: 72%

Quinolone accumulation in Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus

McCaffrey

Bertasso

Pace

et al. 1992

Antimicrob Agents Chemother

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The accumulation of quinolones by Escherichia coli JF568, Pseudomonas aeruginosa PAO1, and Staphylococcus aureus ATCC 29213 was measured by a modified fluorometric assay (J. S. Chapman and N. H. Georgopapadakou, Antimicrob. Agents Chemother. 33:27-29, 1989). The quinolones examined were fleroxacin, pefloxacin, norfloxacin, difloxacin, A56620, ciprofloxacin, ofloxacin, and Ro 09-1168. In all three organisms, uptake was complete in less than 5 min and was proportional to extracellular quinolone concentrations between 2 and 50 ;ag/ml, which is consistent with simple diffusion. Washing cells with quinolone-free buffer decreased accumulation by up Fluoroquinolones are synthetic antibacterial agents with marked bactericidal activities, broad antibacterial spectra, and favorable pharmacokinetics after oral or parenteral administration (25,36,44,48). Their molecular target is DNA gyrase, a unique and essential bacterial enzyme that catalyzes the negative supercoiling (unwinding) of doublestranded DNA and the decatenation of chromosomes after replication (15, 17-19, 23, 24). Quinolones thus interfere with a variety of processes involving DNA, such as replication, chromosomal segregation, transcription, and recombination.The ability of quinolones to enter bacterial cells is a factor contributing to their antibacterial potency (4, 41). Both the outer and cytoplasmic membranes are involved; alterations in either or both are associated with decreased quinolone accumulation and low-level resistance (2, 5-7, 10, 43, 47). In enterobacteria, quinolones diffuse across the outer membrane through the porin channels (13,21,26,27,37) and the phospholipid layer after disrupting the lipopolysaccharide (LPS) (8,20). In Pseudomonas aeruginosa, they diffuse through the D2 protein in the outer membrane and probably through the phospholipid bilayer similarly to enterobacteria (12,16,22,31,33,49). The cytoplasmic membrane is less of a barrier for quinolones, which enter by simple diffusion (2, 5, 26). However, quinolone accumulation is reduced by an active efflux system which is especially prominent in quinolone-resistant strains (11, 29, 51). Nevertheless, permeability plays a secondary role in quinolone susceptibility and resistance, in sharp contrast to the situation with ,B-lactam antibiotics (37).In this study, we have examined the accumulation of several quinolones in Escherichia coli, P. aeruginosa, and Staphylococcus aureus by using a modification of a previously described fluorometric assay (9

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Section: Methodssupporting

confidence: 72%

Quinolone accumulation in Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus

McCaffrey

Bertasso

Pace

et al. 1992

Antimicrob Agents Chemother

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“…It has been proposed that the bulge region of TAR is a metal binding site, as supported by hydrodynamic studies of the influence of metal ion (Mg 2ϩ ) binding on TAR RNA bulge region conformation (57,58). We previously demonstrated how quinolones target single-stranded nucleic acids and the essential contribution of magnesium ions to the mechanism of antibacterial activity (39,41,51,54). Given the ability of quinolones to interact with nucleic acids isolated or complexed to proteins, a similar mechanism of action on nucleic acid-protein complexes may be relevant for antiviral activity.…”

Section: Discussionmentioning

confidence: 96%

“…Physicochemical and enzymatic studies conducted by our group previously identified the quinolone moieties involved in binding to DNA and DNA gyrase (2,40,41). We demonstrated that the interaction between quinolones and the nucleic acid is mediated by magnesium ions and that the complex formation is dependent on ion concentration (39,54).…”

mentioning

confidence: 86%

New Anti-Human Immunodeficiency Virus Type 1 6-Aminoquinolones: Mechanism of Action

Parolin¹,

Gatto

Vecchio³

et al. 2003

Antimicrob Agents Chemother

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“…where Q e is the residue concentration of chemical in earthworms (μmol kg À1 worm ) at the end of the elimination period (day 19) and Q t c is the chemical concentration in earthworms (μmol kg À1 worm ) at the end of the accumulation period (day 7). t c is the time (d) at which earthworms were transferred to the clean pot, and t is the time (d) since the beginning of the experiment.…”

Section: Determination Of CD In Earthworms and Earthwormmentioning

confidence: 99%

“…The molecule in zwitterionic form exhibits the maximum permeation ability, whereas the uptake is strongly reduced when the drug bears a net charge as a result of ionization or complex formation with divalent ions. 19 However, many quinolones possess modified pharmacological and toxicological properties when administered in the form of metallic complexes. When CIP is complexed with Cu(II), Ni(II), Co(II), and Zn(II), the uptake and toxicity of the complexes increases compared to those of the free CIP.…”

Section: Possibility Of Cdàcip Complex Formation In Solutionmentioning

confidence: 99%

Effect of Complexation on the Accumulation and Elimination Kinetics of Cadmium and Ciprofloxacin in the Earthworm Eisenia fetida

Wen

Huang

Wang

et al. 2011

Environ. Sci. Technol.

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Land application of solid wastes leads to the accumulation of both metals and antimicrobials in soils. To understand the effects of metal and antibiotic interaction on their accumulation by the earthworm Eisenia fetida, uptake and elimination kinetics and subcellular distribution of cadmium (Cd) and ciprofloxacin (CIP) were determined. The kinetics was accurately described by a one-compartment first-order kinetic model. Bioaccumulation kinetics and subcellular distribution of CIP were not affected by Cd addition. However, Cd exhibited different metabolic and subcellular distribution patterns. With CIP, Cd uptake flux and elimination rate constants were about 2.2 and 9.8 times, respectively, those without CIP. In the presence of CIP, Cd redistributed from fractions D (associated with granules) and E (associated with tissue fragments and cell membranes) to fraction C (associated with cytosol). Without CIP, Cd in fraction C could not be excreted, whereas with CIP, Cd in fraction C was significantly excreted, and the excretion rate constant was consistent with that of CIP. A good relationship was found between CIP and Cd in earthworms during uptake and elimination periods (p < 0.01). Our results indicated that the CdÀCIP complex may be taken up, stored, and eliminated by earthworms.

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Relevance of ionic effects on norfloxacin uptake by escherichia coli

Cited by 19 publications

References 25 publications

Quinolone accumulation in Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus

Quinolone accumulation in Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus

New Anti-Human Immunodeficiency Virus Type 1 6-Aminoquinolones: Mechanism of Action

Effect of Complexation on the Accumulation and Elimination Kinetics of Cadmium and Ciprofloxacin in the Earthworm Eisenia fetida

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