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Baldassarri L, Montanaro L, Creti R, Arciola CR. Underestimated Collateral Effects of Antibiotic Therapy in Prosthesis-Associated Bacterial Infections. Int J Artif Organs 2018; 30:786-91. [DOI: 10.1177/039139880703000907] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Antibiotic treatment of infections associated with the use of indwelling medical devices in ageing and/or severely ill patients represents a significant healthcare problem due to the difficulty of treating such infections and to the various collateral effects that may be observed following the often aggressive therapy We summarize some effects of antibiotics on the expression of virulence factors of the microorganisms which cause such infections. These effects, particularly those resulting in a stimulation of bacterial virulence, might be usefully included among the other well-known collateral effects of antibiotic therapy
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Affiliation(s)
- L. Baldassarri
- Department of Infectious, Parasitic and Immunomediated Diseases, National Institute of Health, Rome - Italy
| | - L. Montanaro
- Research Unit on Implant Infections, Rizzoli Orthopedic Institute, Bologna - Italy
- Department of Experimental Pathology of the University of Bologna, Bologna - Italy
| | - R. Creti
- Department of Infectious, Parasitic and Immunomediated Diseases, National Institute of Health, Rome - Italy
| | - C. R. Arciola
- Research Unit on Implant Infections, Rizzoli Orthopedic Institute, Bologna - Italy
- Department of Experimental Pathology of the University of Bologna, Bologna - Italy
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2
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Subinhibitory antimicrobial concentrations: A review of in vitro and in vivo data. Can J Infect Dis 2012; 3:193-201. [PMID: 22514370 DOI: 10.1155/1992/793607] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/1990] [Accepted: 03/23/1991] [Indexed: 11/17/2022] Open
Abstract
Antimicrobial activity is not an 'all or none' effect. An increase in the rate and extent of antimicrobial action is usually observed over a wide range of antimicrobial concentrations. Subinhibitory antimicrobial concentrations are well known to produce significant antibacterial effects, and various antimicrobials at subinhibitory concentrations have been reported to inhibit the rate of bacterial growth. Bacterial virulence may be increased or decreased by subinhibitory antimicrobial concentrations by changes in the ability of bacteria to adhere to epithelial cells or by alterations in bacterial susceptibility to host immune defences. Animal studies performed in rats, hamsters and rabbits demonstrate decreased bacterial adherence, reduced infectivity and increased survival of animals treated with subinhibitory antimicrobial concentrations compared to untreated controls. The major future role of investigation of subinhibitory antimicrobial concentrations will be to define more fully, at a molecular level, how antimicrobials exert their antibacterial effects.
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3
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Mortensen NP, Fowlkes JD, Maggart M, Doktycz MJ, Nataro JP, Drusano G, Allison DP. Effects of sub-minimum inhibitory concentrations of ciprofloxacin on enteroaggregative Escherichia coli and the role of the surface protein dispersin. Int J Antimicrob Agents 2011; 38:27-34. [DOI: 10.1016/j.ijantimicag.2011.03.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Revised: 03/08/2011] [Accepted: 03/09/2011] [Indexed: 10/18/2022]
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4
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Evans JA, Adler J, Denyer SP, Cheema MS. The Use of Image Analysis to Examine the Effects of Antibiotics on the Adherence Staphylococcus Epidermidis to Hep2 Cells. J Pharm Pharmacol 2011. [DOI: 10.1111/j.2042-7158.1990.tb14475.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- JA Evans
- Department of Pharmaceutical Sciences, University of Nottingham, Nottingham NG7 2RD
| | - J Adler
- Department of Pharmaceutical Sciences, University of Nottingham, Nottingham NG7 2RD
| | - S P Denyer
- Department of Pharmaceutical Sciences, University of Nottingham, Nottingham NG7 2RD
| | - M S Cheema
- Department of Pharmaceutical Sciences, University of Nottingham, Nottingham NG7 2RD
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5
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Hacker J, Ott M, Hof H. Effects of low, subinhibitory concentrations of antibiotics on expression of a virulence gene cluster of pathogenic Escherichia coli by using a wild-type gene fusion. Int J Antimicrob Agents 2010; 2:263-70. [PMID: 18611540 DOI: 10.1016/0924-8579(93)90060-i] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/03/1993] [Indexed: 10/27/2022]
Abstract
S fimbrial adhesins (Sfa) represent virulence factors of E. coli wild-type strains causing urinary tract infections and meningitis of the new born. In order to determine the influence of subinhibitory concentration of antibiotics on the expression of the sfa gene cluster, a wild-type strain carrying the lacZ gene, coding for the enzyme beta-galactosidase fused to the sfa determinant was used. The expression of lacZ which was under the control of the sfa wild-type promoters, was now equivalent to the sfa gene expression of wild-type strain 536. With this strain the influence of subinhibitory concentrations of 28 antibiotics on the expression of the sfa determinant was studied. The expression was strongly suppressed by a treatment of the wild-type fusion strain by aztreonam, gentamicin, clindamycin and trimethoprim; the latter had a dramatic effect on sfa expression. It was further shown for clindamycin and trimethoprim that the reduction of sfa gene expression was dependent on the concentration of the antibiotics. In contrast imipinem, amphotericin B and rifampicin weakly stimulated sfa expression. We conclude that gene fusions between virulence-associated loci and indicator genes in wild-type pathogens are useful to study virulence modulation due to subinhibitory concentration of antibiotics on the genetic level.
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Affiliation(s)
- J Hacker
- Lehrstuhl für Mikrobiologie, Universität Würzburg, Würzburg, Germany
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6
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Braga PC, Dal SM, Woodnutt G. Staphylococcus aureus and Escherichia coli adhesion to human cells is reduced by sub-MICs of gemifloxacin. J Chemother 2002; 14:41-6. [PMID: 11892898 DOI: 10.1179/joc.2002.14.1.41] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
This study was designed to investigate the capacity of subinhibitory concentrations of the newly developed fluoroquinolone antibiotic gemifloxacin to interfere with the mechanism of bacterial adhesion. Human buccal epithelial cells were incubated with Staphylococcus aureus and Escherichia coli, and grown in the presence of serial dilutions of gemifloxacin from 1/2 MIC to 1/128 MIC. A significant decrease in the adhesion of both S. aureus and E. coli was observed from 1/2 MIC to 1/32 MIC. Morphological changes including filamentous forms of E. coli and cluster formation and swelling of S. aureus were also observed, mainly from 1/2 MIC to 1/8 and 1/16 MIC. These findings are discussed in terms of dose-effect relationships and the interpolation of this pharmacodynamic data with the pharmacokinetics curve of gemifloxacin.
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Affiliation(s)
- P C Braga
- Center of Respiratory Pharmacology, Department of Pharmacology, School of Medicine, University of Milan, Italy.
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7
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Abstract
The science of pharmacodynamics analyzes the relationship between an antimicrobial's bactericidal effects and its pharmacokinetics. Ideally, randomized and well-controlled clinical trials are the best way to determine pharmacodynamic properties. However, in vitro models that recapitulate in vivo drug clearance profiles represent an increasingly important technology for carrying out pharmacodynamic studies in a more cost-effective, timely, and easily controlled fashion. Although in vitro pharmacodynamic models cannot incorporate all variables seen in vivo, they do provide valuable information for the drug development process and the determination of optimal dosing regimens.
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Affiliation(s)
- R L White
- College of Pharmacy, Medical University of South Carolina, Charleston 29425, USA
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8
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Zheng CH, Ahmed K, Rikitomi N, Martinez G, Nagatake T. The effects of S-carboxymethylcysteine and N-acetylcysteine on the adherence of Moraxella catarrhalis to human pharyngeal epithelial cells. Microbiol Immunol 1999; 43:107-13. [PMID: 10229264 DOI: 10.1111/j.1348-0421.1999.tb02381.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We investigated the effects of two mucoregulating drugs, S-carboxymethylcysteine (S-CMC) and N-acetylcysteine (NAC), on the attachment of Moraxella catarrhalis (M. catarrhalis) to pharyngeal epithelial cells. The attachment of M. catarrhalis decreased (33-57%) significantly (P<0.01) in a dose-dependent manner in cells treated with mucoregulating drugs as compared to the control. There was a significant (P<0.01) decrease (35-45%) in the attachment of M. catarrhalis to pharyngeal cells after oral administration of S-CMC. By electron microscopic observation, it was found that there was a fine, granular, electron-dense, ruthenium red-positive layer on the surface of pharyngeal epithelial cells; this layer was absent on cell surfaces treated with mucoregulating drugs. Possibly, this layer contained the portion of M. catarrhalis receptor which is responsible for the attachment of this bacteria to pharyngeal epithelial cells. From the above results, it may be concluded that one of the mechanisms of mucoregulating drugs to decrease the episode of respiratory infections in patients with chronic respiratory diseases is by inhibiting the attachment of bacteria to the upper respiratory tract.
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Affiliation(s)
- C H Zheng
- Department of Internal Medicine, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
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Bisognano C, Vaudaux PE, Lew DP, Ng EY, Hooper DC. Increased expression of fibronectin-binding proteins by fluoroquinolone-resistant Staphylococcus aureus exposed to subinhibitory levels of ciprofloxacin. Antimicrob Agents Chemother 1997; 41:906-13. [PMID: 9145842 PMCID: PMC163823 DOI: 10.1128/aac.41.5.906] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Bacterial adhesion, which plays an important role in Staphylococcus aureus colonization and infection, may be altered by the presence of antibiotics or/and antibiotic resistance determinants. This study evaluated the effect of fluoroquinolone resistance determinants on S. aureus adhesion to solid-phase fibronectin, which is specifically mediated by two surface-located fibronectin-binding proteins. Five isogenic mutants, derived from strain NCTC 8325 and expressing various levels of quinolone resistance, were tested in an in vitro bacterial adhesion assay with polymethylmethacrylate coverslips coated with increasing amounts of fibronectin. These strains contained single or combined mutations in the three major loci contributing to fluoroquinolone resistance, namely, grlA, gyrA, and flqB, which code for altered topoisomerase IV, DNA gyrase, and increased norA-mediated efflux of fluoroquinolones, respectively. Adhesion characteristics of the different quinolone-resistant mutants grown in the absence of fluoroquinolone showed only minor differences from those of parental strains. However, more important changes in adhesion were exhibited by mutants highly resistant to quinolones following their exponential growth in the presence of one-quarter MIC of ciprofloxacin. Increased bacterial adhesion of the highly quinolone-resistant mutants, which contained combined mutations in grlA and gyrA, was associated with and explained by the overexpression of their fibronectin-binding proteins as assessed by Western ligand affinity blotting. These findings contradict the notion that subinhibitory concentrations of antibiotics generally decrease the expression of virulence factors by S. aureus. Perhaps the increased adhesion of S. aureus strains highly resistant to fluoroquinolones contributes in part to that emergence in clinical settings.
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Affiliation(s)
- C Bisognano
- Division of Infectious Diseases, University Hospital, Geneva, Switzerland
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10
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Vranes J, Zagar Z, Kurbel S. Influence of subinhibitory concentrations of ceftazidime, ciprofloxacin and azithromycin on the morphology and adherence of P-fimbriated escherichia coli. J Chemother 1996; 8:254-60. [PMID: 8873829 DOI: 10.1179/joc.1996.8.4.254] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The influence of subinhibitory concentrations (1/2, 1/4, 1/8, 1/16 and 1/32 x MIC) of ceftazidime, ciprofloxacin and azithromycin on the morphology and adherence of 29 wild-type P-fimbriated strains of Escherichia coli was studied. Bacterial adherence to the Buffalo green monkey (BGM) cell line was tested before and after treatment with antibiotics and detected by means of an immunofluorescence staining. Significant dose dependent reduction of bacterial adherence was observed, which correlated with the alterations in bacterial cell morphology. After exposure of strains to sub-MICs of antibiotics, normal shapes, spherical forms and filaments were noted. The greatest filamentation and the greatest loss of adherence ability occurred at 1/2 x MIC of ceftazidime. Treatment with sub-MICs of ciprofloxacin resulted in shorter filaments, while filamentation did not occur after bacterial exposure to sub-MICs of azithromycin. Azithromycin was least damaging to the adherence ability of E. coli and at a concentration of 1/2 x MIC caused globoid cell formation.
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Affiliation(s)
- J Vranes
- Department of Microbiology and Parasitology, University of Zagreb, Medical School, Croatia
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11
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Coe CJ, Doss SA, Tillotson GS, Amyes SG. Interaction of sub-inhibitory concentrations of ciprofloxacin and rifampicin against Staphylococcus aureus. Int J Antimicrob Agents 1995; 5:135-9. [PMID: 18611661 DOI: 10.1016/0924-8579(95)90674-l] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/1994] [Accepted: 09/15/1994] [Indexed: 10/18/2022]
Abstract
The frequency of the emergence of ciprofloxacin-resistant mutants to sub-inhibitory concentrations of ciprofloxacin, rifampicin, and ciprofloxacin plus rifampicin were compared in a subcutaneous abscess model of experimental Staphylococcus aureus infection in mice. The in vitro findings showed that the combination of ciprofloxacin and rifampicin was bacteriostatically additive for all strains tested when the combination was examined by the chequer-board technique and fractional inhibitory concentration indices determined. Animals were infected with ciprofloxacin-sensitive and ciprofloxacin-resistant test strains (6989S and 6989R) and left untreated for nine days, which showed that ciprofloxacin resistance had no effect on the pathogenicity of the organisms. In treated animals, ciprofloxacin plus rifampicin was found to be at least as effective as ciprofloxacin alone. However, in the murine model, the combination therapy produced significantly fewer high-level ciprofloxacin-resistant mutants than ciprofloxacin alone (p<0.0005). We conclude that a combination of ciprofloxacin and rifampicin was at least as efficient as either drug alone, and the additional presence of rifampicin reduced the emergence of high level ciprofloxacin-resistant sub-populations in the case of S. aureus subcutaneous abscesses in mice and so the combination may prove to be more efficient than ciprofloxacin alone.
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Affiliation(s)
- C J Coe
- Department of Medical Microbiology, The Medical School, University of Edinburgh, Teviot Place, Edinburgh EH8 9AG, UK
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12
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Wu Q, Wang Q, Taylor KG, Doyle RJ. Subinhibitory concentrations of antibiotics affect cell surface properties of Streptococcus sobrinus. J Bacteriol 1995; 177:1399-401. [PMID: 7868618 PMCID: PMC176750 DOI: 10.1128/jb.177.5.1399-1401.1995] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Several antibiotics, at subinhibitory concentrations, caused an increase in the ability of Streptococcus sobrinus to bind alpha-1,6-glucans, whereas other antibiotics decreased glucan binding. In every case, glucan binding was inversely proportional to cell surface hydrophobicity. High levels of glucan-binding activity resulted in low levels of hydrophobicity, whereas low levels of glucan binding caused high levels of cellular hydrophobicity. The results show that low concentrations of antibiotics may modulate lectin and hydrophobin adhesins in streptococci.
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Affiliation(s)
- Q Wu
- Department of Microbiology and Immunology, University of Louisville, Kentucky 40292
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13
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Piatti G. Bacterial adhesion to respiratory mucosa and its modulation by antibiotics at sub-inhibitory concentrations. Pharmacol Res 1994; 30:289-99. [PMID: 7716103 DOI: 10.1016/1043-6618(94)80009-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Respiratory infections develop after contact and successive adhesion of micro-organisms to airway mucosa. In fact, the bacterial adhesins are able to interact with a 'lock and key' mechanism with the analogous structures on epithelial surfaces when permissive conditions occur. It was observed that antibiotics at subinhibitory concentrations (sub-MICs) can modify bacterial ability of adhesion to host cells, in various ways. Bacterial adhesion is generally inhibited by antibiotics that, at these concentrations, do not kill bacteria but can change the surface architecture of the micro-organisms.
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Affiliation(s)
- G Piatti
- Department of Pharmacology, School of Medicine, University of Milan, Italy
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14
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Nordström KM, Mozes N. Analysis of wild-type and plasmid-cured Thermus spp. by X-ray photoelectron spectroscopy. Colloids Surf B Biointerfaces 1994. [DOI: 10.1016/0927-7765(94)80019-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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15
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Braga PC, Piatti G. Sub-lethal concentrations of clarithromycin interfere with the expression of Staphylococcus aureus adhesiveness to human cells. J Chemother 1993; 5:159-63. [PMID: 8371124 DOI: 10.1080/1120009x.1993.11739226] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
It has been known for some time that some antibiotics, generally at sub-lethal concentrations, are able to alter the morphology and the shape of bacteria. However, more subtle molecular alterations can also be present, such as disorganization of bacterial surface architecture, which leads to changes in the surface electrical charge that can influence the forces of attraction or repulsion responsible for interaction of bacterial surfaces with environmental surfaces. Bacterial adhesion to epithelial cells is a phenomenon regulated by these mechanisms. Clarithromycin, a new macrolide, at sub-inhibitory concentrations from 1/2 to 1/16 of the MIC, that is to say, from 0.12 to 0.015 microgram/ml, significantly reduces adhesion of Staphylococcus aureus to human buccal epithelial cells. Clarithromycin, as other antibiotics that interfere with the bacterial protein synthesis, should also be able to disturb the synthesis of adhesins. These are ligand molecules located on the surface of bacteria, and thus reduce the ability of bacteria to bind specifically to complementary molecules on the surfaces of epithelial cells which is necessary for host colonization.
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Affiliation(s)
- P C Braga
- Center for Respiratory Pharmacology, School of Medicine, University of Milan, Italy
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16
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Gold BD, Huesca M, Sherman PM, Lingwood CA. Helicobacter mustelae and Helicobacter pylori bind to common lipid receptors in vitro. Infect Immun 1993; 61:2632-8. [PMID: 8500901 PMCID: PMC280894 DOI: 10.1128/iai.61.6.2632-2638.1993] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Helicobacter pylori is a recently recognized human pathogen causing chronic-active gastritis in association with duodenal ulcers and gastric cancer. Helicobacter mustelae is a closely related bacterium with similar biochemical and morphologic characteristics. H. mustelae infection of antral and fundic mucosa in adult ferrets causes chronic gastritis. An essential virulence property of both Helicobacter species is bacterial adhesion to mucosal surfaces. The aim of this study was to determine whether H. mustelae binds to the same lipids shown previously to be receptors for H. pylori adhesion in vitro. By using thin-layer chromatography overlay and a receptor-based enzyme-linked immunosorbent assay, H. mustelae was found to bind the same receptor lipids as H. pylori, namely, phosphatidylethanolamine and gangliotetraosylceramide. In addition, both H. pylori and H. mustelae bound to a deacylplasmalogen phosphatidylethanolamine. In contrast to H. pylori, H. mustelae binding to receptors was unaffected by motility or viability. Murine monoclonal and bovine polyclonal antibodies against exoenzyme S, and exoenzyme S itself (from Pseudomonas aeruginosa), inhibited binding of H. mustelae to phosphatidylethanolamine and gangliotetraosylceramide. These findings show that H. mustelae binds in vitro to the same lipid receptors as H. pylori and suggest that the adhesion of H. mustelae to such species is mediated by preformed, surface-exposed adhesins which include an exoenzyme S-like protein.
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Affiliation(s)
- B D Gold
- Division of Gastroenterology, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
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17
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Visser MR, Beumer H, Hoepelman AI, Rozenberg-Arska M, Verhoef J. Changes in adherence of respiratory pathogens to HEp-2 cells induced by subinhibitory concentrations of sparfloxacin, ciprofloxacin, and trimethoprim. Antimicrob Agents Chemother 1993; 37:885-8. [PMID: 8388203 PMCID: PMC187797 DOI: 10.1128/aac.37.4.885] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Preincubation with subinhibitory concentrations of sparfloxacin, ciprofloxacin, and trimethoprim decreased the adherence of the respiratory pathogens Klebsiella pneumoniae, Haemophilus influenzae, and Moraxella (Branhamella) catarrhalis to human larynx carcinoma HEp-2 cells. Subinhibitory concentrations of sparfloxacin did not change the adherence of Pseudomonas aeruginosa or Streptococcus pneumoniae 15.62, but adhesion of S. pneumoniae 15.42 was significantly enhanced by subinhibitory antimicrobial concentrations.
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Affiliation(s)
- M R Visser
- Department of Clinical Microbiology, University Hospital Utrecht, The Netherlands
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18
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Adhesins of uropathogenic bacteria: Properties, identification and use for new antibacterial strategies. Int Urogynecol J 1992. [DOI: 10.1007/bf00499649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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19
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Viljanen P, Boratynski J. The susceptibility of conjugative resistance transfer in gram-negative bacteria to physicochemical and biochemical agents. FEMS Microbiol Rev 1991; 8:43-54. [PMID: 1931138 DOI: 10.1111/j.1574-6968.1991.tb04956.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Over thirty years of studies have established that conjugative transfer of plasmid-encoded resistance to drugs and heavy metals can take place at high frequency between various organisms under laboratory conditions. The detected transfer frequencies in soil, in aquatic environments, and in the urogenital and respiratory tracts of healthy animals and man have generally been low. However, the conversion of bacteria from susceptible to resistant to antibiotics has been observed often during antimicrobial therapy. This has formed a challenge for the antibacterial treatment of pathogenic bacteria and called for the evaluation of the extent of conjugative transfer in various environments. Several biochemical and physicochemical factors inhibit conjugation, show preferential toxicity against plasmid-bearing cells, or stimulate plasmid curing. These factors include various agents such as detergents, anesthetics, mutagens and antibiotics which affect membrane potential, membrane permeability, protein synthesis and the processing of DNA. The application of the data on these agents, summarized in this review, might be helpful in preventing drug multi-resistance from spreading. Also these data might be valuable in studies which use conjugation as a tool or which treat the molecular mechanisms involved in conjugation.
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Affiliation(s)
- P Viljanen
- Miyazaki University, Faculty of Agriculture, Japan
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20
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Sherman P, Cockerill F, Soni R, Brunton J. Outer membranes are competitive inhibitors of Escherichia coli O157:H7 adherence to epithelial cells. Infect Immun 1991; 59:890-9. [PMID: 1671778 PMCID: PMC258344 DOI: 10.1128/iai.59.3.890-899.1991] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Escherichia coli of serotype O157:H7 are Vero cytotoxin-producing enteric pathogens that have been associated recently with sporadic cases and outbreaks of hemorrhagic colitis and with the hemolytic-uremic syndrome. Adherence of many enteropathogenic bacteria to mucosal surfaces is a critical step in the pathogenesis of diarrheal disease. We showed previously that adherence of E. coli O157:H7 strain CL-56 to epithelial cells in vitro is inhibited by outer membranes. In this study we examined whether outer membranes from a series of E. coli O157:H7 strains mediated competitive inhibition of bacterial binding to epithelial cells grown in tissue culture. We also determined which constituents of the outer membrane mediated inhibition of CL-56 adherence. Binding of six O157:H7 strains to HEp-2 cells was determined by quantitating the number of adherent bacteria in the presence and absence of outer membranes which were extracted from each strain with N-lauroyl sarcosinate (1.7%, wt/vol). After separation of outer membranes by gel electrophoresis, four bands (94, 40, 36, and 30 kDa) were collected by electroelution. Immune sera were raised in rabbits to each of the four eluted bands. Outer membrane extracts from each of the six O157:H7 strains inhibited binding of homologous organisms to the HEp-2 cells. At dilutions which did not cause bacterial agglutination, antiserum raised against the 94-kDa outer membrane protein showed maximal inhibition of bacterial adherence (17.0 +/- 7.3% adherence of control levels). Growth of bacteria in iron-depleted broth did not affect their binding to HEp-2 cells, suggesting that iron-regulated outer membranes were not involved. Fluid accumulation in ileal ligated loops of rabbits in response to E. coli O157:H7 challenge was diminished following both parenteral immunization with outer membranes extracted from the homologous strain and coincubation of organisms with immune serum which contained antibodies to outer membrane extracts. These data indicate that outer membranes are competitive inhibitors of E. coli O157:H7 adherence. Specific constituents of the outer membrane may function as bacterial attachment factors (i.e., adhesins) for E. coli O157:H7 adherence to epithelial cell surfaces.
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Affiliation(s)
- P Sherman
- Division of Gastroenterology, Hospital for Sick Children, University of Toronto, Ontario, Canada
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21
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Suerbaum S, Leying H, Meyer B, Opferkuch W. Influence of beta-lactam antibiotics on serum resistance of K1-positive blood culture isolates of Escherichia coli. Antimicrob Agents Chemother 1990; 34:628-31. [PMID: 2188587 PMCID: PMC171655 DOI: 10.1128/aac.34.4.628] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The K1-positive strains of Escherichia coli are a group with considerable clinical importance, serum resistance being a common virulence factor of these strains. In the present paper, the influences of cephaloridine, imipenem, and ceftazidime on the serum resistance of eight serum-resistant K1-positive E. coli blood culture isolates with smooth-type lipopolysaccharide were studied. All strains were rendered more serum sensitive by treatment with subinhibitory concentrations of antibiotics. The amount of the reduction of serum resistance was dependent on the concentration of the antibiotic. Amounts of K1 produced under the influence of the antibiotics were measured and were found to be reduced for almost all strains tested. To further test the hypothesis that antibiotic-induced reduction of serum resistance is mediated by inhibition of K1 expression, isogenic mutants of one strain were produced by selection for resistance against infection with K1-specific bacteriophages. These mutants were found to be highly serum sensitive. We conclude from this study that beta-lactam antibiotics can render K1-positive serum-resistant strains of E. coli highly serum sensitive and that this effect is mediated by inhibition of K1 expression.
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Affiliation(s)
- S Suerbaum
- Medizinische Mikrobiologie und Immunologie, Ruhr-Universität Bochum, Federal Republic of Germany
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Cavallero A, Eftimiadi C, Radin L, Schito GC. Suppression of tricarboxylic acid cycle in Escherichia coli exposed to sub-MICs of aminoglycosides. Antimicrob Agents Chemother 1990; 34:295-301. [PMID: 2183717 PMCID: PMC171576 DOI: 10.1128/aac.34.2.295] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The metabolic activity of Escherichia coli ATCC 25922 challenged with sub-MICs of aminoglycosides was analyzed with a batch calorimeter. High-performance and gas-liquid chromatographic techniques were utilized to evaluate the concentrations of metabolic reactants, intermediates, and end products. The data reported indicate that aminoglycosides inhibit or delay bacterial catabolism of carboxylic acids, with the following relative degrees of activity: amikacin greater than gentamicin greater than sisomicin greater than netilmicin greater than kanamycin. The decrease in total biomass production was proportional to the degree of tricarboxylic acid cycle inhibition.
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Affiliation(s)
- A Cavallero
- Institute of Microbiology, Medical School, University of Genoa, Italy
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23
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Chopra I, Hacker K. Effects of tetracyclines on the production of extracellular proteins by members of the propionibacteriaceae. FEMS Microbiol Lett 1989. [DOI: 10.1111/j.1574-6968.1989.tb03412.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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24
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Kovarik JM, Hoepelman IM, Verhoef J. Influence of fluoroquinolones on expression and function of P fimbriae in uropathogenic Escherichia coli. Antimicrob Agents Chemother 1989; 33:684-8. [PMID: 2568772 PMCID: PMC172514 DOI: 10.1128/aac.33.5.684] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
P fimbriae are the major adhesins mediating attachment of pyelonephritogenic Escherichia coli to urinary tract tissues, and they therefore constitute a recognized virulence factor. In this work, the effect of fluoroquinolones on P fimbria expression and function in E. coli SS142 and C1212 was assessed. Ciprofloxacin, fleroxacin, and norfloxacin were compared with their precursor nalidixic acid and with trimethoprim in sublethal concentrations ranging from 1/32 to 1/4 of the MIC. Fimbria function was assessed in a standard hemagglutination assay and in a parallel hemagglutination inhibition assay in which the tier of antifimbrial antiserum necessary to inhibit hemagglutination by SS142 was determined. Adhesion of antibiotic-exposed bacteria to human uroma T24 cells in suspension was also measured. Fimbria production was quantitated in an inhibition enzyme-linked immunosorbent assay. Trimethoprim produced a dose-dependent decrease of three to four hemagglutination titers for both strains and a decline in the antiserum titer from 1:16 (control) to 1:128 (1/4 MIC) for E. coli SS142. Adherence exhibited similar decrements from 130 +/- 28 (control) to 16 +/- 3 (1/4 MIC) and from 83 +/- 19 (control) to 30 +/- 11 (1/4 MIC) E. coli cells per uroepithelial cell (mean +/- standard error) for SS142 and C1212, respectively (P less than 0.015). By enzyme-linked immunosorbent assay, the inhibition following exposure decreased in a dose-dependent manner from 31% (control) to 8% (1/4 MIC). By contrast, none of the quinolones produced significant changes in the parameters assessed above. At sublethal concentrations, trimethoprim decreased fimbria production. Following exposure to fluoroquinolones, however, E. coli expressed morphologically and functionally intact P fimbriae.
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Affiliation(s)
- J M Kovarik
- Department of Medical Microbiology, University Hospital of Utrecht, The Netherlands
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25
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Schifferli DM, Beachey EH. Bacterial adhesion: modulation by antibiotics with primary targets other than protein synthesis. Antimicrob Agents Chemother 1988; 32:1609-13. [PMID: 2472773 PMCID: PMC175937 DOI: 10.1128/aac.32.11.1609] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Affiliation(s)
- D M Schifferli
- Department of Microbiology and Immunology, University of Tennessee Center for the Health Sciences, Memphis
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