201
|
Bacanlı M, Başaran N. Importance of antibiotic residues in animal food. Food Chem Toxicol 2019; 125:462-466. [DOI: 10.1016/j.fct.2019.01.033] [Citation(s) in RCA: 154] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 01/25/2019] [Accepted: 01/28/2019] [Indexed: 01/25/2023]
|
202
|
Martins KB, Ferreira AM, Pereira VC, Pinheiro L, de Oliveira A, da Cunha MDLRDS. In vitro Effects of Antimicrobial Agents on Planktonic and Biofilm Forms of Staphylococcus saprophyticus Isolated From Patients With Urinary Tract Infections. Front Microbiol 2019; 10:40. [PMID: 30745897 PMCID: PMC6360166 DOI: 10.3389/fmicb.2019.00040] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 01/11/2019] [Indexed: 12/30/2022] Open
Abstract
Bacterial biofilms play an important role in urinary tract infections (UTIs), being responsible for persistent infections that lead to recurrences and relapses. Staphylococcus saprophyticus is one of the main etiological agents of UTIs, however, little is known about biofilm production in this species and especially about its response to the antimicrobial agents used to treat UTIs when a biofilm is present. For this reason, the aim of this work was to evaluate the response of S. saprophyticus biofilms to five antimicrobial agents. Staphylococcus saprophyticus was evaluated for antimicrobial susceptibility in its planktonic form by means of minimum inhibitory concentration (MIC) and in biofilms by means of minimum inhibitory concentration in biofilm (MICB) against the following antimicrobial agents by the microdilution technique: vancomycin, oxacillin, trimethoprim/sulfamethoxazole, ciprofloxacin, and norfloxacin. Of the 169 S. saprophyticus studied, 119 produced a biofilm as demonstrated by the polystyrene plate adherence method. Biofilm cells of S. saprophyticus exhibited a considerable increase in MICB when compared to the planktonic forms, with an increase of more than 32 times in the MICB of some drugs. Some isolates switched from the category of susceptible in the planktonic condition to resistant in the biofilm state. Statistical analysis of the results showed a significant increase in MICB (p < 0.0001) for all five drugs tested in the biofilm state compared to the planktonic form. Regarding determination of the minimum bactericidal concentration in biofilm (MBCB), there were isolates for which the minimum bactericidal concentration of all drugs was equal to or higher than the highest concentration tested.
Collapse
Affiliation(s)
- Katheryne Benini Martins
- Department of Microbiology and Immunology, Institute of Biosciences, UNESP - Universidade Estadual Paulista, Botucatu, Brazil
| | - Adriano Martison Ferreira
- Department of Microbiology and Immunology, Institute of Biosciences, UNESP - Universidade Estadual Paulista, Botucatu, Brazil.,Department of Tropical Diseases, Botucatu School of Medicine University Hospital, UNESP - Universidade Estadual Paulista, Botucatu, Brazil
| | - Valéria Cataneli Pereira
- Department of Microbiology and Immunology, Institute of Biosciences, UNESP - Universidade Estadual Paulista, Botucatu, Brazil
| | - Luiza Pinheiro
- Department of Microbiology and Immunology, Institute of Biosciences, UNESP - Universidade Estadual Paulista, Botucatu, Brazil
| | - Adilson de Oliveira
- Department of Microbiology and Immunology, Institute of Biosciences, UNESP - Universidade Estadual Paulista, Botucatu, Brazil
| | | |
Collapse
|
203
|
Yasir M, Willcox MDP, Dutta D. Action of Antimicrobial Peptides against Bacterial Biofilms. MATERIALS 2018; 11:ma11122468. [PMID: 30563067 PMCID: PMC6317029 DOI: 10.3390/ma11122468] [Citation(s) in RCA: 161] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 11/30/2018] [Accepted: 12/01/2018] [Indexed: 12/22/2022]
Abstract
Microbes are known to colonize surfaces and form biofilms. These biofilms are communities of microbes encased in a self-produced matrix that often contains polysaccharides, DNA and proteins. Antimicrobial peptides (AMPs) have been used to control the formation and to eradicate mature biofilms. Naturally occurring or synthetic antimicrobial peptides have been shown to prevent microbial colonization of surfaces, to kill bacteria in biofilms and to disrupt the biofilm structure. This review systemically analyzed published data since 1970 to summarize the possible anti-biofilm mechanisms of AMPs. One hundred and sixty-two published reports were initially selected for this review following searches using the criteria ‘antimicrobial peptide’ OR ‘peptide’ AND ‘mechanism of action’ AND ‘biofilm’ OR ‘antibiofilm’ in the databases PubMed; Scopus; Web of Science; MEDLINE; and Cochrane Library. Studies that investigated anti-biofilm activities without describing the possible mechanisms were removed from the analysis. A total of 17 original reports were included which have articulated the mechanism of antimicrobial action of AMPs against biofilms. The major anti-biofilm mechanisms of antimicrobial peptides are: (1) disruption or degradation of the membrane potential of biofilm embedded cells; (2) interruption of bacterial cell signaling systems; (3) degradation of the polysaccharide and biofilm matrix; (4) inhibition of the alarmone system to avoid the bacterial stringent response; (5) downregulation of genes responsible for biofilm formation and transportation of binding proteins.
Collapse
Affiliation(s)
- Muhammad Yasir
- School of Optometry and Vision Science, University of New South Wales, Sydney, NSW 2052, Australia.
| | | | - Debarun Dutta
- School of Optometry and Vision Science, University of New South Wales, Sydney, NSW 2052, Australia.
| |
Collapse
|
204
|
Ben-Hur S, Biton M, Regev-Rudzki N. Extracellular Vesicles: A Prevalent Tool for Microbial Gene Delivery? Proteomics 2018; 19:e1800170. [PMID: 30358122 DOI: 10.1002/pmic.201800170] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 10/02/2018] [Indexed: 01/08/2023]
Abstract
Genetic plasticity of prokaryotic microbial communities is largely dependent on the ongoing exchange of genetic determinants by Horizontal Gene Transfer (HGT). HGT events allow beneficial genetic transitions to occur throughout microbial life, thus promoting adaptation to changing environmental conditions. Here, the significance of secreted vesicles in mediating HGT between microorganisms is discussed, while focusing on the benefits gained by vesicle-mediated gene delivery and its occurrence under different environmental cues. The potential use of secreted DNA-harboring vesicles as a mechanism of currently unresolved HGT events in eukaryotic microbes is further discussed.
Collapse
Affiliation(s)
- Sharon Ben-Hur
- Faculty of Biochemistry, Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Mirit Biton
- Faculty of Biochemistry, Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Neta Regev-Rudzki
- Faculty of Biochemistry, Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| |
Collapse
|
205
|
Pannekens M, Kroll L, Müller H, Mbow FT, Meckenstock RU. Oil reservoirs, an exceptional habitat for microorganisms. N Biotechnol 2018; 49:1-9. [PMID: 30502541 PMCID: PMC6323355 DOI: 10.1016/j.nbt.2018.11.006] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 11/27/2018] [Accepted: 11/27/2018] [Indexed: 01/21/2023]
Abstract
Water-containing parts within oil reservoirs extend the zone of biodegradation. Biodegradation is controlled by environmental factors. Proteobacteria and Euryarchaeota are ubiquitous in oil reservoirs over all temperature ranges. Biofilms as microbial adaption in oil reservoirs. Viruses as potential control for microbial activity and function.
Microorganisms are present in oil reservoirs around the world where they degrade oil and lead to changes in oil quality. Unfortunately, our knowledge about processes in deep oil reservoirs is limited due to the lack of undisturbed samples. In this review, we discuss the distribution of microorganisms at the oil-water transition zone as well as in water saturated parts of the oil leg and their possible physiological adaptations to abiotic and biotic ecological factors such as temperature, salinity and viruses. We show the importance of studying the water phase within the oil, because small water inclusions and pockets within the oil leg provide an exceptional habitat for microorganisms within a natural oil reservoir and concurrently enlarge the zone of oil biodegradation. Environmental factors such as temperature and salinity control oil biodegradation. Temperature determines the type of microorganisms which are able to inhabit the reservoir. Proteobacteria and Euryarchaeota, are ubiquitous in oil reservoirs over all temperature ranges, whereas some others are tied to specific temperatures. It is proposed that biofilm formation is the dominant way of life within oil reservoirs, enhancing nutrient uptake, syntrophic interactions and protection against environmental stress. Literature shows that viruses are abundant in oil reservoirs and the possible impact on microbial community composition due to control of microbial activity and function is discussed.
Collapse
Affiliation(s)
- Mark Pannekens
- University of Duisburg-Essen, Biofilm Centre, Universitätsstr. 5, 41451, Essen, Germany
| | - Lisa Kroll
- University of Duisburg-Essen, Biofilm Centre, Universitätsstr. 5, 41451, Essen, Germany
| | - Hubert Müller
- University of Duisburg-Essen, Biofilm Centre, Universitätsstr. 5, 41451, Essen, Germany
| | - Fatou Tall Mbow
- University of Duisburg-Essen, Biofilm Centre, Universitätsstr. 5, 41451, Essen, Germany
| | - Rainer U Meckenstock
- University of Duisburg-Essen, Biofilm Centre, Universitätsstr. 5, 41451, Essen, Germany.
| |
Collapse
|
206
|
Zhou G, Wang YS, Peng H, Huang XM, Xie XB, Shi QS. Role of Ttca of Citrobacter Werkmanii in Bacterial Growth, Biocides Resistance, Biofilm Formation and Swimming Motility. Int J Mol Sci 2018; 19:E2644. [PMID: 30200616 PMCID: PMC6165289 DOI: 10.3390/ijms19092644] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 08/28/2018] [Accepted: 08/30/2018] [Indexed: 01/10/2023] Open
Abstract
To screen, identify and study the genes involved in isothiazolone resistance and biofilm formation in Citrobacter werkmanii strain BF-6. A Tn5 transposon library of approximately 900 mutants of C. werkmanii strain BF-6 was generated and screened to isolate 1,2-benzisothiazolin-3-one (BIT) resistant strains. In addition, the tRNA 2-thiocytidine (32) synthetase gene (ttcA) was deleted through homologous recombination and the resulting phenotypic changes of the ΔttcA mutant were studied. A total of 3 genes were successfully identified, among which ΔttcA mutant exhibited a reduction in growth rate and swimming motility. On the other hand, an increase in biofilms formation in ΔttcA were observed but not with a significant resistance enhancement to BIT. This work, for the first time, highlights the role of ttcA gene of C. werkmanii strain BF-6 in BIT resistance and biofilm formation.
Collapse
Affiliation(s)
- Gang Zhou
- Guangdong Open Laboratory of Applied Microbiology, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, Guangdong 510070, China.
| | - Ying-Si Wang
- Guangdong Open Laboratory of Applied Microbiology, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, Guangdong 510070, China.
| | - Hong Peng
- Guangdong Open Laboratory of Applied Microbiology, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, Guangdong 510070, China.
| | - Xiao-Mo Huang
- Guangdong Open Laboratory of Applied Microbiology, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, Guangdong 510070, China.
| | - Xiao-Bao Xie
- Guangdong Open Laboratory of Applied Microbiology, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, Guangdong 510070, China.
| | - Qing-Shan Shi
- Guangdong Open Laboratory of Applied Microbiology, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangzhou, Guangdong 510070, China.
| |
Collapse
|
207
|
Biofilm Formation by Staphylococcus aureus Isolated from Food Contact Surfaces in the Dairy Industry of Jalisco, Mexico. J FOOD QUALITY 2018. [DOI: 10.1155/2018/1746139] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Staphylococcus aureus is an important food-borne pathogen able to form biofilms. This pathogen is responsible for outbreaks of food-borne illnesses associated with the consumption of milk and dairy products. The aim of this study was to evaluate the biofilm-forming ability of S. aureus isolates, recovered from food contact surfaces in the dairy industry of Jalisco, Mexico. A total of 84 S. aureus strains were evaluated. The isolates were characterized phenotypically by culture on Congo red agar plates. The ability of the strains to form biofilms was investigated in 96-well flat-bottomed microtiter polystyrene plates. Stainless-steel coupons were used as an experimental surface. Biofilm formation was observed, using epifluorescence microscopy and scanning electron microscopy. Detection of the icaADBC genes in S. aureus was performed by the PCR technique. A total of 52.3% (44/84) of the S. aureus strains contained the icaADBC gene that synthesizes polysaccharide intercellular adhesion (PIA) molecules. On Congo red agar, 75% (63/84) of the S. aureus isolates were biofilm producers, 16.6% (14/84) were non-biofilm formers, and 8.3% (7/84) showed a noncharacteristic phenotype. The biofilm production of the S. aureus strains SA-4E, SA-9, SA-13, and SA-19 on stainless-steel coupons was investigated at 25°C for 8 days, and the detected cell population density was approximately 7.15–7.82 log CFU cm−2. In addition to the ability of biofilm production, it is important to highlight that these strains are potential enterotoxin producers as se genes have been previously detected in their genomes. A part of the ability of biofilm production and the determination of the presence of virulence determinants in the genome of S. aureus can contribute to the pathogenicity of strains. Therefore, vigilant food safety practices need to be implemented in the dairy industries regarding FCS to prevent food-borne infections and intoxications due to S. aureus contamination.
Collapse
|
208
|
James GA, Chesnel L, Boegli L, deLancey Pulcini E, Fisher S, Stewart PS. Analysis of Clostridium difficile biofilms: imaging and antimicrobial treatment. J Antimicrob Chemother 2018; 73:102-108. [PMID: 29029221 DOI: 10.1093/jac/dkx353] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 08/30/2017] [Indexed: 01/05/2023] Open
Abstract
Background Clostridium difficile, a spore-forming Gram-positive anaerobic bacillus, is the most common causative agent of healthcare-associated diarrhoea. Formation of biofilms may protect C. difficile against antibiotics, potentially leading to treatment failure. Furthermore, bacterial spores or vegetative cells may linger in biofilms in the gut causing C. difficile infection recurrence. Objectives In this study, we evaluated and compared the efficacy of four antibiotics (fidaxomicin, surotomycin, vancomycin and metronidazole) in penetrating C. difficile biofilms and killing vegetative cells. Methods C. difficile biofilms grown initially for 48 or 72 h using the colony biofilm model were then treated with antibiotics at a concentration of 25 × MIC for 24 h. Vegetative cells and spores were enumerated. The effect of treatment on biofilm structure was studied by scanning electron microscopy (SEM). The ability of fidaxomicin and surotomycin to penetrate biofilms was studied using fluorescently tagged antibiotics. Results Both surotomycin and fidaxomicin were significantly more effective than vancomycin or metronidazole (P < 0.001) at killing vegetative cells in established biofilms. Fidaxomicin was more effective than metronidazole at reducing viable spore counts in biofilms (P < 0.05). Fluorescently labelled surotomycin and fidaxomicin penetrated C. difficile biofilms in < 1 h. After 24 h of treatment, SEM demonstrated that both fidaxomicin and surotomycin disrupted the biofilm structure, while metronidazole had no observable effect. Conclusions Fidaxomicin is effective in disrupting C. difficile biofilms, killing vegetative cells and decreasing spore counts.
Collapse
Affiliation(s)
- Garth A James
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
| | | | - Laura Boegli
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
| | | | - Steve Fisher
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
| | - Philip S Stewart
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
| |
Collapse
|
209
|
Bonebrake M, Anderson K, Valiente J, Jacobson A, McLean JE, Anderson A, Britt DW. Biofilms Benefiting Plants Exposed to ZnO and CuO Nanoparticles Studied with a Root-Mimetic Hollow Fiber Membrane. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:6619-6627. [PMID: 28926236 DOI: 10.1021/acs.jafc.7b02524] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Plants exist with a consortium of microbes that influence plant health, including responses to biotic and abiotic stress. While nanoparticle (NP)-plant interactions are increasingly studied, the effect of NPs on the plant microbiome is less researched. Here a root-mimetic hollow fiber membrane (HFM) is presented for generating biofilms of plant-associated microbes nurtured by artificial root exudates (AREs) to correlate exudate composition with biofilm formation and response to NPs. Two microbial isolates from field-grown wheat, a bacillus endophyte and a pseudomonad root surface colonizer, were examined on HFMs fed with AREs varying in N and C composition. Bacterial morphology and biofilm architecture were characterized using scanning electron microscopy (SEM) and atomic force microscopy (AFM) and responses to CuO and ZnO NP challenges of 300 mg/L evaluated. The bacillus isolate sparsely colonized the HFM. In contrast, the pseudomonad formed robust biofilms within 3 days. Dependent on nutrient sources, the biofilm cells produced extensive extracellular polymeric substances (EPS) and large intracellular granules. Pseudomonad biofilms were minimally affected by ZnO NPs. CuO NPs, when introduced before biofilm maturation, strongly reduced biofilm formation. The findings demonstrate the utility of the HFM root-mimetic to study rhizoexudate influence on biofilms of root-colonizing microbes but without active plant metabolism. The results will allow better understanding of how microbe-rhizoexudate-NP interactions affect microbial and plant health.
Collapse
Affiliation(s)
- Michelle Bonebrake
- Department of Biological Engineering , Utah State University , Logan , Utah 84322 , United States
| | - Kaitlyn Anderson
- Department of Biological Engineering , Utah State University , Logan , Utah 84322 , United States
| | - Jonathan Valiente
- Department of Biological Engineering , Utah State University , Logan , Utah 84322 , United States
| | - Astrid Jacobson
- Plants Soils Climate , Utah State University , Logan , Utah 84322 , United States
| | - Joan E McLean
- Utah Water Research Laboratory , Utah State University , Logan , Utah 84322 , United States
| | - Anne Anderson
- Department of Biology , Utah State University , Logan , Utah 84322 , United States
| | - David W Britt
- Department of Biological Engineering , Utah State University , Logan , Utah 84322 , United States
| |
Collapse
|
210
|
Reygaert WC. An overview of the antimicrobial resistance mechanisms of bacteria. AIMS Microbiol 2018; 4:482-501. [PMID: 31294229 PMCID: PMC6604941 DOI: 10.3934/microbiol.2018.3.482] [Citation(s) in RCA: 604] [Impact Index Per Article: 100.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 06/13/2018] [Indexed: 01/29/2023] Open
Abstract
Resistance to antimicrobial agents has become a major source of morbidity and mortality worldwide. When antibiotics were first introduced in the 1900's, it was thought that we had won the war against microorganisms. It was soon discovered however, that the microorganisms were capable of developing resistance to any of the drugs that were used. Apparently most pathogenic microorganisms have the capability of developing resistance to at least some antimicrobial agents. The main mechanisms of resistance are: limiting uptake of a drug, modification of a drug target, inactivation of a drug, and active efflux of a drug. These mechanisms may be native to the microorganisms, or acquired from other microorganisms. Understanding more about these mechanisms should hopefully lead to better treatment options for infective diseases, and development of antimicrobial drugs that can withstand the microorganisms attempts to become resistant.
Collapse
Affiliation(s)
- Wanda C Reygaert
- Department of Biomedical Sciences, Oakland University William Beaumont School of Medicine, Rochester, MI, USA
| |
Collapse
|
211
|
Bellich B, Lagatolla C, Tossi A, Benincasa M, Cescutti P, Rizzo R. Influence of Bacterial Biofilm Polysaccharide Structure on Interactions with Antimicrobial Peptides: A Study on Klebsiella pneumoniae. Int J Mol Sci 2018; 19:ijms19061685. [PMID: 29882774 PMCID: PMC6032227 DOI: 10.3390/ijms19061685] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 05/18/2018] [Accepted: 06/01/2018] [Indexed: 11/20/2022] Open
Abstract
Biofilms are complex systems produced by bacteria and constituted by macromolecular matrix embedding cells. They provide advantages to bacteria including protection against antimicrobials. The protection given by biofilms produced by Klebsiella pneumoniae strains towards antimicrobial peptides of the innate immune system was investigated. In particular, the role of matrix bacterial exopolysaccharides was explored. Three clinical strains producing exopolysaccharides with different chemistry were selected and the interaction of purified biofilm polysaccharides with two bovine cathelicidins was studied by circular dichroism spectroscopy and microbiological assays to establish their influence on the peptide’s antimicrobial activity. The spectroscopic data indicated a different extent of interaction with the two peptides, in a manner dependent on their sugar composition, and in particular the presence of rhamnose residues correlated with a lower interaction. The extent of interaction was then related to the protection towards antimicrobial peptides, conferred by the addition of the different exopolysaccharides, in minimum inhibitory concentration (MIC) assays against a reference Escherichia coli strain. Microbiological results were in very good agreement with spectroscopic data, confirming the active role of matrix polysaccharides in determining a biofilm’s protective capacity and indicating lower protection levels afforded by rhamnose containing exopolysaccharides.
Collapse
Affiliation(s)
- Barbara Bellich
- Department of Life Sciences, University of Trieste, Via Licio Giorgieri 1, 34127 Trieste, Italy.
| | - Cristina Lagatolla
- Department of Life Sciences, University of Trieste, Via Licio Giorgieri 1, 34127 Trieste, Italy.
| | - Alessandro Tossi
- Department of Life Sciences, University of Trieste, Via Licio Giorgieri 1, 34127 Trieste, Italy.
| | - Monica Benincasa
- Department of Life Sciences, University of Trieste, Via Licio Giorgieri 1, 34127 Trieste, Italy.
| | - Paola Cescutti
- Department of Life Sciences, University of Trieste, Via Licio Giorgieri 1, 34127 Trieste, Italy.
| | - Roberto Rizzo
- Department of Life Sciences, University of Trieste, Via Licio Giorgieri 1, 34127 Trieste, Italy.
| |
Collapse
|
212
|
Wang YC, Huang TW, Yang YS, Kuo SC, Chen CT, Liu CP, Liu YM, Chen TL, Chang FY, Wu SH, How CK, Lee YT. Biofilm formation is not associated with worse outcome in Acinetobacter baumannii bacteraemic pneumonia. Sci Rep 2018; 8:7289. [PMID: 29740176 PMCID: PMC5940913 DOI: 10.1038/s41598-018-25661-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 04/20/2018] [Indexed: 02/07/2023] Open
Abstract
The effect of biofilm formation on bacteraemic pneumonia caused by A. baumannii is unknown. We conducted a 4-year multi-center retrospective study to analyze 71 and 202 patients with A. baumannii bacteraemic pneumonia caused by biofilm-forming and non-biofilm-forming isolates, respectively. The clinical features and outcomes of patients were investigated. Biofilm formation was determined by a microtitre plate assay. The antimicrobial susceptibilities of biofilm-associated cells were assessed using the minimum biofilm eradication concentration (MBEC) assay. Whole-genome sequencing was conducted to identify biofilm-associated genes and their promoters. Quantitative reverse transcription polymerase chain reaction was performed to confirm the expression difference of biofilm-associated genes. There was no significant difference in the clinical characteristics or the outcomes between patients infected with biofilm-forming and non-biofilm-forming strains. Compared with non-biofilm-forming isolates, biofilm-forming isolates exhibited lower resistance to most antimicrobials tested, including imipenem, meropenem, ceftazidime, ciprofloxacin and gentamicin; however, the MBEC assay confirmed the increased antibiotic resistance of the biofilm-embedded bacteria. Biofilm-associated genes and their promoters were detected in most isolates, including the non-biofilm-forming strains. Biofilm-forming isolates showed higher levels of expression of the biofilm-associated genes than non-biofilm-forming isolates. The biofilm-forming ability of A. baumannii isolates might not be associated with worse outcomes in patients with bacteraemic pneumonia.
Collapse
Affiliation(s)
- Yung-Chih Wang
- Division of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.,Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Tzu-Wen Huang
- Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Ya-Sung Yang
- Division of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Shu-Chen Kuo
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institute, Maoli County, Taiwan
| | - Chung-Ting Chen
- Department of Emergency Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Chang-Pan Liu
- Division of Infectious Diseases, Department of Internal Medicine, Mackay Memorial Hospital, Taipei, Taiwan.,Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan
| | - Yuag-Meng Liu
- Division of Infectious Diseases, Department of Internal Medicine, Changhua Christian Hospital, Changhua, Taiwan
| | - Te-Li Chen
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan.,Division of Infectious Diseases, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Feng-Yee Chang
- Division of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Shih-Hsiung Wu
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Chorng-Kuang How
- Department of Emergency Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Yi-Tzu Lee
- Department of Emergency Medicine, Taipei Veterans General Hospital, Taipei, Taiwan. .,Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
| |
Collapse
|
213
|
Pseudomonas aeruginosa Biofilm Antibiotic Resistance Gene ndvB Expression Requires the RpoS Stationary-Phase Sigma Factor. Appl Environ Microbiol 2018; 84:AEM.02762-17. [PMID: 29352081 DOI: 10.1128/aem.02762-17] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 01/11/2018] [Indexed: 01/21/2023] Open
Abstract
Chronic, biofilm-based bacterial infections are exceptionally difficult to eradicate due to the high degree of antibiotic recalcitrance exhibited by cells in biofilm communities. In the opportunistic pathogen Pseudomonas aeruginosa, biofilm recalcitrance is multifactorial and arises in part from the preferential expression of resistance genes in biofilms compared to exponential-phase planktonic cells. One such mechanism involves ndvB, which we have previously shown to be expressed specifically in biofilms. In this study, we investigated the regulatory basis of this lifestyle-specific expression by developing an unstable green fluorescent protein (GFP) transcriptional reporter to observe the expression pattern of ndvB We found that in addition to its expression in biofilms, ndvB was upregulated in planktonic cells as they enter stationary phase. The transcription of ndvB in both growth phases was shown to be dependent on the stationary-phase sigma factor RpoS, and mutation of a putative RpoS binding site in the ndvB promoter abolished the activity of the promoter in stationary-phase cells. Overall, we have expanded our understanding of the temporal expression of ndvB in P. aeruginosa and have uncovered a regulatory basis for its growth phase-dependent expression.IMPORTANCE Bacterial biofilms are more resistant to antibiotics than free-living planktonic cells, and understanding the mechanistic basis of this resistance can inform treatments of biofilm-based infections. In addition to chemical and structural barriers that can inhibit antibiotic entry, the upregulation of specific genes in biofilms contributes to the resistance. We investigated this biofilm-specific gene induction by examining expression patterns of ndvB, a gene involved in biofilm resistance of the opportunistic pathogen Pseudomonas aeruginosa We characterized ndvB expression in planktonic and biofilm growth conditions with an unstable green fluorescent protein (GFP) reporter and found that the expression of ndvB in biofilms is dependent on the stationary-phase sigma factor RpoS. Overall, our results support the physiological similarity between biofilms and stationary-phase cells and suggest that the induction of some stationary-phase genes in biofilms may contribute to their increased antibiotic resistance.
Collapse
|
214
|
Von Borowski RG, Macedo AJ, Gnoatto SCB. Peptides as a strategy against biofilm-forming microorganisms: Structure-activity relationship perspectives. Eur J Pharm Sci 2018; 114:114-137. [DOI: 10.1016/j.ejps.2017.11.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 10/20/2017] [Accepted: 11/08/2017] [Indexed: 10/18/2022]
|
215
|
Subramenium GA, Swetha TK, Iyer PM, Balamurugan K, Pandian SK. 5-hydroxymethyl-2-furaldehyde from marine bacterium Bacillus subtilis inhibits biofilm and virulence of Candida albicans. Microbiol Res 2018; 207:19-32. [DOI: 10.1016/j.micres.2017.11.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 10/20/2017] [Accepted: 11/04/2017] [Indexed: 01/09/2023]
|
216
|
Dos Santos Ramos MA, Da Silva PB, Spósito L, De Toledo LG, Bonifácio BV, Rodero CF, Dos Santos KC, Chorilli M, Bauab TM. Nanotechnology-based drug delivery systems for control of microbial biofilms: a review. Int J Nanomedicine 2018; 13:1179-1213. [PMID: 29520143 PMCID: PMC5834171 DOI: 10.2147/ijn.s146195] [Citation(s) in RCA: 148] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Since the dawn of civilization, it has been understood that pathogenic microorganisms cause infectious conditions in humans, which at times, may prove fatal. Among the different virulent properties of microorganisms is their ability to form biofilms, which has been directly related to the development of chronic infections with increased disease severity. A problem in the elimination of such complex structures (biofilms) is resistance to the drugs that are currently used in clinical practice, and therefore, it becomes imperative to search for new compounds that have anti-biofilm activity. In this context, nanotechnology provides secure platforms for targeted delivery of drugs to treat numerous microbial infections that are caused by biofilms. Among the many applications of such nanotechnology-based drug delivery systems is their ability to enhance the bioactive potential of therapeutic agents. The present study reports the use of important nanoparticles, such as liposomes, microemulsions, cyclodextrins, solid lipid nanoparticles, polymeric nanoparticles, and metallic nanoparticles, in controlling microbial biofilms by targeted drug delivery. Such utilization of these nanosystems has led to a better understanding of their applications and their role in combating biofilms.
Collapse
Affiliation(s)
- Matheus Aparecido Dos Santos Ramos
- São Paulo State University (UNESP), School of Pharmaceutical Sciences, Campus Araraquara, Department of Biological Sciences, Araraquara, SP, Brazil
| | - Patrícia Bento Da Silva
- São Paulo State University (UNESP), School of Pharmaceutical Sciences, Campus Araraquara, Department of Drugs and Medicines. Araraquara, SP, Brazil
| | - Larissa Spósito
- São Paulo State University (UNESP), School of Pharmaceutical Sciences, Campus Araraquara, Department of Biological Sciences, Araraquara, SP, Brazil
| | - Luciani Gaspar De Toledo
- São Paulo State University (UNESP), School of Pharmaceutical Sciences, Campus Araraquara, Department of Biological Sciences, Araraquara, SP, Brazil
| | - Bruna Vidal Bonifácio
- São Paulo State University (UNESP), School of Pharmaceutical Sciences, Campus Araraquara, Department of Biological Sciences, Araraquara, SP, Brazil
| | - Camila Fernanda Rodero
- São Paulo State University (UNESP), School of Pharmaceutical Sciences, Campus Araraquara, Department of Drugs and Medicines. Araraquara, SP, Brazil
| | - Karen Cristina Dos Santos
- São Paulo State University (UNESP), School of Pharmaceutical Sciences, Campus Araraquara, Department of Drugs and Medicines. Araraquara, SP, Brazil
| | - Marlus Chorilli
- São Paulo State University (UNESP), School of Pharmaceutical Sciences, Campus Araraquara, Department of Drugs and Medicines. Araraquara, SP, Brazil
| | - Taís Maria Bauab
- São Paulo State University (UNESP), School of Pharmaceutical Sciences, Campus Araraquara, Department of Biological Sciences, Araraquara, SP, Brazil
| |
Collapse
|
217
|
Hall CW, Mah TF. Molecular mechanisms of biofilm-based antibiotic resistance and tolerance in pathogenic bacteria. FEMS Microbiol Rev 2018; 41:276-301. [PMID: 28369412 DOI: 10.1093/femsre/fux010] [Citation(s) in RCA: 849] [Impact Index Per Article: 141.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 02/22/2017] [Indexed: 02/06/2023] Open
Abstract
Biofilms are surface-attached groups of microbial cells encased in an extracellular matrix that are significantly less susceptible to antimicrobial agents than non-adherent, planktonic cells. Biofilm-based infections are, as a result, extremely difficult to cure. A wide range of molecular mechanisms contribute to the high degree of recalcitrance that is characteristic of biofilm communities. These mechanisms include, among others, interaction of antimicrobials with biofilm matrix components, reduced growth rates and the various actions of specific genetic determinants of antibiotic resistance and tolerance. Alone, each of these mechanisms only partially accounts for the increased antimicrobial recalcitrance observed in biofilms. Acting in concert, however, these defences help to ensure the survival of biofilm cells in the face of even the most aggressive antimicrobial treatment regimens. This review summarises both historical and recent scientific data in support of the known biofilm resistance and tolerance mechanisms. Additionally, suggestions for future work in the field are provided.
Collapse
|
218
|
Feng J, Liu B, Xu J, Wang Q, Huang L, Ou W, Gu J, Wu J, Li S, Zhuo C, Zhou Y. In vitro effects of N-acetylcysteine alone and combined with tigecycline on planktonic cells and biofilms of Acinetobacter baumannii. J Thorac Dis 2018; 10:212-218. [PMID: 29600051 DOI: 10.21037/jtd.2017.11.130] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Background Acinetobacter baumannii (A. baumannii), as a common opportunistic pathogen, has strong ability to form biofilms, which has led to drug resistance and chronic infections. The combination of N-acetylcysteine (NAC) and tigecycline (TGC) was demonstrated to synergistically inhibit biofilm-associated bacterial infections, including methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis. The purpose of this study is to investigate the effect of NAC and TGC on planktonic cells and biofilms of A. baumannii. Methods Minimum inhibitory concentrations (MICs) of NAC were determined by broth microdilution method. Biofilm susceptibility was assessed by crystal violet stain. Interactive effects of NAC and TGC on planktonic cells were determined by checkerboard MIC assay. Viable cell count was used to evaluate the combined effect of NAC and TGC on biofilm-embedded bacteria. Results MICs of NAC against 25 A. baumannii isolates ranged from 16 to 128 mg/mL. NAC alone (0.5-128 mg/mL) significantly inhibited biofilm formation and disrupted preformed biofilms. The combination of NAC and TGC induced a partial synergistic effect (60%) and additive effect (28%) on planktonic bacteria. For biofilm-embedded bacteria, treatment with 16 mg/mL NAC alone or 2 µg/mL TGC alone resulted in significant bactericidal effects (P<0.01 and P<0.05, respectively); synergistic bactericidal effect was found at 4 mg/mL NAC combined with 0.5 µg/mL TGC (P<0.01). Conclusions NAC alone significantly inhibited biofilm formation of A. baumannii. The combination of NAC and TGC induced partial synergistic effect against planktonic cells and synergistic effect against biofilm-embedded A. baumannii, which might be a therapeutic option for biofilm-related infections of A. baumannii.
Collapse
Affiliation(s)
- Jinlun Feng
- Department of Respiratory Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Baomo Liu
- Department of Respiratory Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Junwen Xu
- Department of Respiratory Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Qinqin Wang
- Department of Respiratory Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Lixia Huang
- Department of Respiratory Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Weijun Ou
- Center of Organ Transplantation, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Jincui Gu
- Department of Respiratory Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Jian Wu
- Department of Respiratory Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Shaoli Li
- Department of Respiratory Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| | - Chao Zhuo
- State Key Laboratory of Respiratory Diseases, Guangzhou Medical College, Guangzhou 511436, China
| | - Yanbin Zhou
- Department of Respiratory Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China
| |
Collapse
|
219
|
Bogdan M, Drenjancevic D, Harsanji Drenjancevic I, Bedenic B, Zujic Atalic V, Talapko J, Vukovic D. In vitro effect of subminimal inhibitory concentrations of antibiotics on the biofilm formation ability of Acinetobacter baumannii clinical isolates. J Chemother 2017; 30:16-24. [PMID: 28956494 DOI: 10.1080/1120009x.2017.1378835] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The ability of A cinetobacter baumannii strains to form biofilm is one of the most important virulence factor which enables bacterial survival in a harsh environment and decreases antibiotic concentration as well. Subminimal inhibitory concentrations (subMICs) of antibiotics may change bacterial ultrastructure or have an influence on some different molecular mechanisms resulting in morphological or physiological changes in bacteria itself. The aim of this study was to determine effects of 1/2, 1/4, 1/8 and 1/16 minimal inhibitory concentrationsof imipenem, ampicillin-sulbactam, azithromycin, rifampicin and colistin on biofilm formation ability of 22 biofilm non-producing and 46 biofilm producing A. baumannii strains (30 weak producing strains and 16 moderate producing strains). Results of this study indicate that 1/2-1/16 MICs of imipenem, azithromycin, and rifampicin can reduce bacterial biofilm formation ability in moderate producing strains (p < 0.05), whereas 1/16 MIC of imipenem and 1/4-1/8 MICs of rifampicin reduce the biofilm formation in weak producing strains (p < 0.05). Statisticaly significant effect was detected among biofilm non-producing strains after their exposure to 1/16 MIC of azithromycin (p = 0.039). SubMICs of ampicillin-sulbactam and colistin did not have any significant effect on biofilm formation among tested A. baumannii strains.
Collapse
Affiliation(s)
- Maja Bogdan
- a Microbiology Service , Institute of Public Health Osijek-Baranja County , Osijek , Croatia.,b Faculty of Medicine, Department of Microbiology and Parasitology , University of Osijek , Osijek , Croatia
| | - Domagoj Drenjancevic
- b Faculty of Medicine, Department of Microbiology and Parasitology , University of Osijek , Osijek , Croatia.,c Department of Transfusion Medicine , Osijek University Hospital , Osijek , Croatia
| | - Ivana Harsanji Drenjancevic
- d Department of Anesthesiology, Reanimatology and Intensive Medicine , Osijek University Hospital , Osijek , Croatia.,e Faculty of Medicine, Department of Anesthesiology, Reanimatology and Intensive Medicine , University of Osijek , Osijek , Croatia
| | - Branka Bedenic
- f Department of Clinical and Molecular Microbiology , University Hospital Center Zagreb , Zagreb , Croatia.,g Department of Microbiology and Parasitology , School of Medicine, University of Zagreb , Zagreb , Croatia
| | - Vlasta Zujic Atalic
- a Microbiology Service , Institute of Public Health Osijek-Baranja County , Osijek , Croatia.,b Faculty of Medicine, Department of Microbiology and Parasitology , University of Osijek , Osijek , Croatia
| | - Jasminka Talapko
- b Faculty of Medicine, Department of Microbiology and Parasitology , University of Osijek , Osijek , Croatia
| | - Dubravka Vukovic
- a Microbiology Service , Institute of Public Health Osijek-Baranja County , Osijek , Croatia
| |
Collapse
|
220
|
Dutta Sinha S, Das S, Tarafdar S, Dutta T. Monitoring of Wild Pseudomonas Biofilm Strain Conditions Using Statistical Characterization of Scanning Electron Microscopy Images. Ind Eng Chem Res 2017. [DOI: 10.1021/acs.iecr.7b01106] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Suparna Dutta Sinha
- Condensed Matter Physics Research Centre, Department of Physics, Jadavpur University, Kolkata−700032, India
| | - Saptarshi Das
- Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, U.K
- Department of Power
Engineering, Jadavpur University, Salt Lake Campus, LB-8, Sector 3, Kolkata−700098, India
| | - Sujata Tarafdar
- Condensed Matter Physics Research Centre, Department of Physics, Jadavpur University, Kolkata−700032, India
| | - Tapati Dutta
- Physics Department, St. Xavier’s College, Kolkata−700016, India
| |
Collapse
|
221
|
Taylor PK, Van Kessel ATM, Colavita A, Hancock REW, Mah TF. A novel small RNA is important for biofilm formation and pathogenicity in Pseudomonas aeruginosa. PLoS One 2017; 12:e0182582. [PMID: 28771593 PMCID: PMC5542712 DOI: 10.1371/journal.pone.0182582] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 07/20/2017] [Indexed: 01/08/2023] Open
Abstract
The regulation of biofilm development requires multiple mechanisms and pathways, but it is not fully understood how these are integrated. Small RNA post-transcriptional regulators are a strong candidate as a regulatory mechanism of biofilm formation. More than 200 small RNAs in the P. aeruginosa genome have been characterized in the literature to date; however, little is known about their biological roles in the cell. Here we describe the identification of the novel regulatory small RNA, SrbA. This locus was up-regulated 45-fold in P. aeruginosa strain PA14 biofilm cultures. Loss of SrbA expression in a deletion strain resulted in a 66% reduction in biofilm mass. Furthermore, the mortality rate over 72 hours in C. elegans infections was reduced to 39% when infected with the srbA deletion strain compared to 78% mortality when infected with the parental wild-type P. aeruginosa strain. There was no significant effect on culture growth or adherence to surfaces with loss of SrbA expression. Also loss of SrbA expression had no effect on antibiotic resistance to ciprofloxacin, gentamicin, and tobramycin. We conclude that SrbA is important for biofilm formation and full pathogenicity of P. aeruginosa.
Collapse
Affiliation(s)
- Patrick K. Taylor
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Antonius T. M. Van Kessel
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Antonio Colavita
- Neuroscience Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - Robert E. W. Hancock
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Thien-Fah Mah
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| |
Collapse
|
222
|
Flemming HC, Wingender J, Szewzyk U, Steinberg P, Rice SA, Kjelleberg S. Biofilms: an emergent form of bacterial life. Nat Rev Microbiol 2017; 14:563-75. [PMID: 27510863 DOI: 10.1038/nrmicro.2016.94] [Citation(s) in RCA: 2762] [Impact Index Per Article: 394.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Bacterial biofilms are formed by communities that are embedded in a self-produced matrix of extracellular polymeric substances (EPS). Importantly, bacteria in biofilms exhibit a set of 'emergent properties' that differ substantially from free-living bacterial cells. In this Review, we consider the fundamental role of the biofilm matrix in establishing the emergent properties of biofilms, describing how the characteristic features of biofilms - such as social cooperation, resource capture and enhanced survival of exposure to antimicrobials - all rely on the structural and functional properties of the matrix. Finally, we highlight the value of an ecological perspective in the study of the emergent properties of biofilms, which enables an appreciation of the ecological success of biofilms as habitat formers and, more generally, as a bacterial lifestyle.
Collapse
Affiliation(s)
- Hans-Curt Flemming
- University of Duisburg-Essen, Faculty of Chemistry, Biofilm Centre, Universitätsstrasse 5, D-45141 Essen, Germany
| | - Jost Wingender
- University of Duisburg-Essen, Faculty of Chemistry, Biofilm Centre, Universitätsstrasse 5, D-45141 Essen, Germany
| | - Ulrich Szewzyk
- Technical University of Berlin, Department of Environmental Microbiology, Ernst-Reuter-Platz 1, D-10587 Berlin, Germany
| | - Peter Steinberg
- The School of Biological, Earth and Environmental Sciences and The Centre for Marine Bio-Innovation, University of New South Wales, Sydney, NSW 2052, Australia
| | - Scott A Rice
- The Singapore Centre for Environmental Life Sciences Engineering and the School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Staffan Kjelleberg
- The Singapore Centre for Environmental Life Sciences Engineering and the School of Biological Sciences, Nanyang Technological University, Singapore 637551
| |
Collapse
|
223
|
Salem WM, Shibat El-Hamed DMW, Sayed WF, Elamary RB. Alterations in virulence and antibiotic resistant genes of multidrug-resistant Salmonella serovars isolated from poultry: The bactericidal efficacy of Allium sativum. Microb Pathog 2017; 108:91-100. [PMID: 28479511 DOI: 10.1016/j.micpath.2017.05.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Revised: 04/27/2017] [Accepted: 05/02/2017] [Indexed: 12/13/2022]
Affiliation(s)
- W M Salem
- South Valley University, Faculty of Science, Botany Department, 83523, Qena, Egypt.
| | | | - W F Sayed
- South Valley University, Faculty of Science, Botany Department, 83523, Qena, Egypt
| | - R B Elamary
- South Valley University, Faculty of Science, Botany Department, 83523, Qena, Egypt
| |
Collapse
|
224
|
Sun Y, Ye J, Hou Y, Chen H, Cao J, Zhou T. Predation Efficacy of Bdellovibrio bacteriovorus on Multidrug-Resistant Clinical Pathogens and Their Corresponding Biofilms. Jpn J Infect Dis 2017; 70:485-489. [PMID: 28367880 DOI: 10.7883/yoken.jjid.2016.405] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The aim of the present study was to evaluate the predation efficacy of Bdellovibrio bacteriovorus on multidrug-resistant (MDR) or extensive drug resistant (XDR) gram-negative pathogens and their corresponding biofilms. In this study, we examined the ability of B. bacteriovorus to prey on MDR and XDR gram-negative clinical bacteria, including Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii. Results showed that B. bacteriovorus was able to prey on all planktonic cultures, among which the most efficient predation was observed for drug-resistant E. coli, with a 3.11 log10 reduction in viability. Furthermore, B. bacteriovorus demonstrated promising efficacy in preventing biofilm formation and dispersing the established biofilm. Reductions in biofilm formation of E. coli, K. pneumoniae, P. aeruginosa, and A. baumannii co-cultured with B. bacteriovorus were 65.2%, 37.1%, 44.7%, and 36.8%, respectively. Meanwhile, the established biofilms of E. coli, K. pneumoniae, P. aeruginosa, and A. baumannii were significantly reduced by 83.4%, 81.8%, 83.1%, and 79.9%, respectively. A visual analysis supported by scanning electron microscopy demonstrated the role of B. bacteriovorus in removing the established biofilms. This study highlights the potential use of B. bacteriovorus as a biological control agent with the capability to prey on MDR/XDR gram-negative pathogens and eradicate biofilms.
Collapse
Affiliation(s)
- Yao Sun
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University
| | - Jianzhong Ye
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, The First Affiliated Hospital, College of Medicine.,Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University
| | - Yuanbo Hou
- School of Laboratory Medicine and Life Science, Wenzhou Medical University
| | - Huale Chen
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University
| | - Jianming Cao
- School of Laboratory Medicine and Life Science, Wenzhou Medical University
| | - Tieli Zhou
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University
| |
Collapse
|
225
|
Attaran B, Falsafi T, Ghorbanmehr N. Effect of biofilm formation by clinical isolates of Helicobacter pylori on the efflux-mediated resistance to commonly used antibiotics. World J Gastroenterol 2017; 23:1163-1170. [PMID: 28275296 PMCID: PMC5323441 DOI: 10.3748/wjg.v23.i7.1163] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 11/11/2016] [Accepted: 01/04/2017] [Indexed: 02/06/2023] Open
Abstract
AIM To evaluate the role of biofilm formation on the resistance of Helicobacter pylori (H. pylori) to commonly prescribed antibiotics, the expression rates of resistance genes in biofilm-forming and planktonic cells were compared.
METHODS A collection of 33 H. pylori isolates from children and adult patients with chronic infection were taken for the present study. The isolates were screened for biofilm formation ability, as well as for polymerase chain reaction (PCR) reaction with HP1165 and hp1165 efflux pump genes. Susceptibilities of the selected strains to antibiotic and differences between susceptibilities of planktonic and biofilm-forming cell populations were determined. Quantitative real-time PCR (qPCR) analysis was performed using 16S rRNA gene as a H. pylori-specific primer, and two efflux pumps-specific primers, hp1165 and hefA.
RESULTS The strains were resistant to amoxicillin, metronidazole, and erythromycin, except for one strain, but they were all susceptible to tetracycline. Minimum bactericidal concentrations of antibiotics in the biofilm-forming cells were significantly higher than those of planktonic cells. qPCR demonstrated that the expression of efflux pump genes was significantly higher in the biofilm-forming cells as compared to the planktonic ones.
CONCLUSION The present work demonstrated an association between H. pylori biofilm formation and decreased susceptibility to all the antibiotics tested. This decreased susceptibility to antibiotics was associated with enhanced functional activity of two efflux pumps: hp1165 and hefA.
Collapse
|
226
|
Beaudoin T, Kennedy S, Yau Y, Waters V. Visualizing the Effects of Sputum on Biofilm Development Using a Chambered Coverglass Model. J Vis Exp 2016. [PMID: 28060284 DOI: 10.3791/54819] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Biofilms consist of groups of bacteria encased in a self-secreted matrix. They play an important role in industrial contamination as well as in the development and persistence of many health related infections. One of the most well described and studied biofilms in human disease occurs in chronic pulmonary infection of cystic fibrosis patients. When studying biofilms in the context of the host, many factors can impact biofilm formation and development. In order to identify how host factors may affect biofilm formation and development, we used a static chambered coverglass method to grow biofilms in the presence of host-derived factors in the form of sputum supernatants. Bacteria are seeded into chambers and exposed to sputum filtrates. Following 48 hr of growth, biofilms are stained with a commercial biofilm viability kit prior to confocal microscopy and analysis. Following image acquisition, biofilm properties can be assessed using different software platforms. This method allows us to visualize key properties of biofilm growth in presence of different substances including antibiotics.
Collapse
Affiliation(s)
- Trevor Beaudoin
- Physiology and Experimental Medicine, Hospital for Sick Children;
| | - Sarah Kennedy
- Department of Clinical Microbiology, Royal College of Surgeons in Ireland
| | - Yvonne Yau
- Department of Laboratory Medicine and Pathobiology, University of Toronto
| | | |
Collapse
|
227
|
Santos-Beneit F, Ordóñez-Robles M, Martín JF. Glycopeptide resistance: Links with inorganic phosphate metabolism and cell envelope stress. Biochem Pharmacol 2016; 133:74-85. [PMID: 27894856 DOI: 10.1016/j.bcp.2016.11.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 11/15/2016] [Indexed: 10/20/2022]
Abstract
Antimicrobial resistance is a critical health issue today. Many pathogens have become resistant to many or all available antibiotics and limited new antibiotics are in the pipeline. Glycopeptides are used as a 'last resort' antibiotic treatment for many bacterial infections, but worryingly, glycopeptide resistance has spread to very important pathogens such as Enterococcus faecium and Staphylococcus aureus. Bacteria confront multiple stresses in their natural environments, including nutritional starvation and the action of cell-wall stressing agents. These stresses impact bacterial susceptibility to different antimicrobials. This article aims to review the links between glycopeptide resistance and different stresses, especially those related with cell-wall biosynthesis and inorganic phosphate metabolism, and to discuss promising alternatives to classical antibiotics to avoid the problem of antimicrobial resistance.
Collapse
Affiliation(s)
- Fernando Santos-Beneit
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Medical School, Newcastle University, NE2 4AX Newcastle upon Tyne, UK
| | - María Ordóñez-Robles
- Department of Biotechnology, Faculty of Natural Sciences and Technology, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Juan F Martín
- Microbiology Area, Department of Molecular Biology, University of León, 24071 León, Spain.
| |
Collapse
|
228
|
Marioni J, da Silva MA, Cabrera JL, Montoya SCN, Paraje MG. The anthraquinones rubiadin and its 1-methyl ether isolated from Heterophyllaea pustulata reduces Candida tropicalis biofilms formation. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2016; 23:1321-1328. [PMID: 27765351 DOI: 10.1016/j.phymed.2016.07.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 07/05/2016] [Accepted: 07/19/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND Candida tropicalis is increasingly becoming among the most commonly isolated pathogens causing fungal infections with an important biofilm-forming capacity. PURPOSE This study addresses the antifungal effect of rubiadin (AQ1) and rubiadin 1-methyl ether (AQ2), two photosensitizing anthraquinones (AQs) isolated from Heterophyllaea pustulata, against C. tropicalis biofilms, by studying the cellular stress and antioxidant response in two experimental conditions: darkness and irradiation. The combination with Amphotericin B (AmB) was assayed to evaluate the synergic effect. STUDY DESIGN/METHODS Biofilms of clinical isolates and reference strain of Candida tropicalis were treated with AQs (AQ1 or AQ2) and/or AmB, and the biofilms depletion was studied by crystal violet and confocal scanning laser microscopy (CSLM). The oxidant metabolites production and the response of antioxidant defense system were also evaluated under dark and irradiation conditions, being the light a trigger for photo-activation of the AQs. The Reactive Oxygen Species (ROS) were detected by the reduction of Nitro Blue Tetrazolium test, and Reactive Nitrogen Intermediates (RNI) by the Griess assay. ROS accumulation was also detected inside biofilms by using 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) probe, which was visualized by CSLM. Superoxide dismutase (SOD) activity and the total antioxidant capacity of biofilms were measured by spectrophotometric methods. The minimun inhibitory concentration for sessile cells (SMIC) was determined for each AQs and AmB. The fractional inhibitory concentration index (FICI) was calculated for the combinations of each AQ with AmB by the checkerboard microdilution method. RESULTS Biofilm reduction of both strains was more effective with AQ1 than with AQ2. The antifungal effect was mediated by an oxidative and nitrosative stress under irradiation, with a significant accumulation of endogenous ROS detected by CSLM and an increase in the SOD activity. Thus, the prooxidant-antioxidant balance was altered especially by AQ1. The best synergic combination with AmB was also obtained with AQ1 (80.5%) (FICI=0.74). CONCLUSION Under irradiation, the oxidative stress was the predominant effect, altering the prooxidant-antioxidant balance, which may be the cause of the irreversible cell injury in the biofilm. Our results showed synergism of these natural AQs with AmB. Therefore, the photosensitizing AQ1 could be an alternative for the Candida infections treatment, which deserves further investigation.
Collapse
Affiliation(s)
- Juliana Marioni
- Instituto Multidisciplinario de Biología Vegetal (IMBIV) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Departamento de Farmacia, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina. Haya de la Torre y Medina Allende, X5000HUA Córdoba, Argentina
| | - María Angel da Silva
- Instituto Multidisciplinario de Biología Vegetal (IMBIV) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Cátedra de Microbiología, Facultad de Ciencias Exactas Físicas y Naturales. Universidad Nacional de Córdoba, Argentina. Av. Vélez Sarsfield 299, Córdoba, Argentina
| | - José Luis Cabrera
- Instituto Multidisciplinario de Biología Vegetal (IMBIV) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Departamento de Farmacia, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina. Haya de la Torre y Medina Allende, X5000HUA Córdoba, Argentina
| | - Susana C Núñez Montoya
- Instituto Multidisciplinario de Biología Vegetal (IMBIV) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Departamento de Farmacia, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina. Haya de la Torre y Medina Allende, X5000HUA Córdoba, Argentina
| | - María Gabriela Paraje
- Instituto Multidisciplinario de Biología Vegetal (IMBIV) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Cátedra de Microbiología, Facultad de Ciencias Exactas Físicas y Naturales. Universidad Nacional de Córdoba, Argentina. Av. Vélez Sarsfield 299, Córdoba, Argentina.
| |
Collapse
|
229
|
Klančnik A, Šikić Pogačar M, Trošt K, Tušek Žnidarič M, Mozetič Vodopivec B, Smole Možina S. Anti-Campylobacter activity of resveratrol and an extract from waste Pinot noir grape skins and seeds, and resistance of Camp. jejuni planktonic and biofilm cells, mediated via the CmeABC efflux pump. J Appl Microbiol 2016; 122:65-77. [PMID: 27709726 DOI: 10.1111/jam.13315] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 08/05/2016] [Accepted: 09/22/2016] [Indexed: 12/20/2022]
Abstract
AIMS To define anti-Campylobacter jejuni activity of an extract from waste skins and seeds of Pinot noir grapes (GSS), resveratrol and possible resistance mechanisms, and the influence of these on Camp. jejuni morphology. METHODS AND RESULTS Using gene-specific knock-out Camp. jejuni mutants and an efflux pump inhibitor, we showed CmeABC as the most active efflux pump for extrusion across the outer membrane of GSS extract and resveratrol. Using polystyrene surface and pig small intestine epithelial (PSI) and human foetal small intestine (H4) cell lines, GSS extract shows an efficient inhibition of adhesion of Camp. jejuni to these abiotic and biotic surfaces. CONCLUSIONS Low doses of GSS extract can inhibit Camp. jejuni adhesion to polystyrene surfaces and to PSI and H4 cells, and can thus modulate Camp. jejuni invasion and intracellular survival. SIGNIFICANCE AND IMPACT OF THE STUDY An understanding of the activities of GSS extract and resveratrol as bacterial growth inhibitors and the specific mechanisms of cell accumulation is crucial for our understanding of Camp. jejuni resistance. GSS extract inhibition of Camp. jejuni adhesion to abiotic and biotic surfaces provides a further step towards the application of new innovative strategies to control Campylobacter contamination and infection via the food chain.
Collapse
Affiliation(s)
- A Klančnik
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - M Šikić Pogačar
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia.,Medical Faculty, University of Maribor, Maribor, Slovenia
| | - K Trošt
- Wine Research Centre, University of Nova Gorica, Vipava, Slovenia
| | - M Tušek Žnidarič
- Department of Biotechnology and System Biology, National Institute of Biology, Ljubljana, Slovenia
| | | | - S Smole Možina
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| |
Collapse
|
230
|
Li Y, Cao S, Zhang L, Lau GW, Wen Y, Wu R, Zhao Q, Huang X, Yan Q, Huang Y, Wen X. A TolC-Like Protein of Actinobacillus pleuropneumoniae Is Involved in Antibiotic Resistance and Biofilm Formation. Front Microbiol 2016; 7:1618. [PMID: 27822201 PMCID: PMC5075564 DOI: 10.3389/fmicb.2016.01618] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/28/2016] [Indexed: 11/13/2022] Open
Abstract
Actinobacillus pleuropneumoniae is the etiologic agent of porcine contagious pleuropneumonia, a significant disease that causes serious economic losses to the swine industry worldwide. Persistent infections caused by bacterial biofilms are recalcitrant to treat because of the particular drug resistance of biofilm-dwelling cells. TolC, a key component of multidrug efflux pumps, are responsible for multidrug resistance (MDR) in many Gram-negative bacteria. In this study, we identified two TolC-like proteins, TolC1 and TolC2, in A. pleuropneumoniae. Deletion of tolC1, but not tolC2, caused a significant reduction in biofilm formation, as well as increased drug sensitivity of both planktonic and biofilm cells. The genetic-complementation of the tolC1 mutation restored the competent biofilm and drug resistance. Besides, biofilm formation was inhibited and drug sensitivity was increased by the addition of phenylalanine-arginine beta-naphthylamide (PAβN), a well-known efflux pump inhibitor (EPI), suggesting a role for EPI in antibacterial strategies toward drug tolerance of A. pleuropneumoniae. Taken together, TolC1 is required for biofilm formation and is a part of the MDR machinery of both planktonic and biofilm cells, which could supplement therapeutic strategies for resistant bacteria and biofilm-related infections of A. pleuropneumoniae clinical isolate SC1516.
Collapse
Affiliation(s)
- Ying Li
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Sanjie Cao
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Luhua Zhang
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural UniversityChengdu, China; Department of Pathobiology, University of Illinois at Urbana-ChampaignUrbana, IL, USA
| | - Gee W Lau
- Department of Pathobiology, University of Illinois at Urbana-Champaign Urbana, IL, USA
| | - Yiping Wen
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Rui Wu
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Qin Zhao
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Xiaobo Huang
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Qigui Yan
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Yong Huang
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| | - Xintian Wen
- Research Center of Swine Diseases, College of Veterinary Medicine, Sichuan Agricultural University Chengdu, China
| |
Collapse
|
231
|
Viszwapriya D, Prithika U, Deebika S, Balamurugan K, Pandian SK. In vitro and in vivo antibiofilm potential of 2,4-Di- tert -butylphenol from seaweed surface associated bacterium Bacillus subtilis against group A streptococcus. Microbiol Res 2016; 191:19-31. [DOI: 10.1016/j.micres.2016.05.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Revised: 04/11/2016] [Accepted: 05/20/2016] [Indexed: 02/08/2023]
|
232
|
Abstract
The genus Burkholderia comprises metabolically diverse and adaptable Gram-negative bacteria, which thrive in often adversarial environments. A few members of the genus are prominent opportunistic pathogens. These include Burkholderia mallei and Burkholderia pseudomallei of the B. pseudomallei complex, which cause glanders and melioidosis, respectively. Burkholderia cenocepacia, Burkholderia multivorans, and Burkholderia vietnamiensis belong to the Burkholderia cepacia complex and affect mostly cystic fibrosis patients. Infections caused by these bacteria are difficult to treat because of significant antibiotic resistance. The first line of defense against antimicrobials in Burkholderia species is the outer membrane penetration barrier. Most Burkholderia contain a modified lipopolysaccharide that causes intrinsic polymyxin resistance. Contributing to reduced drug penetration are restrictive porin proteins. Efflux pumps of the resistance nodulation cell division family are major players in Burkholderia multidrug resistance. Third and fourth generation β-lactam antibiotics are seminal for treatment of Burkholderia infections, but therapeutic efficacy is compromised by expression of several β-lactamases and ceftazidime target mutations. Altered DNA gyrase and dihydrofolate reductase targets cause fluoroquinolone and trimethoprim resistance, respectively. Although antibiotic resistance hampers therapy of Burkholderia infections, the characterization of resistance mechanisms lags behind other non-enteric Gram-negative pathogens, especially ESKAPE bacteria such as Acinetobacter baumannii, Klebsiella pneumoniae and Pseudomonas aeruginosa.
Collapse
Affiliation(s)
- Katherine A Rhodes
- Department of Molecular Genetics and Microbiology, College of Medicine, Emerging Pathogens Institute and Institute for Therapeutic Innovation, University of Florida, Gainesville, FL, USA; Department of Microbiology Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Herbert P Schweizer
- Department of Molecular Genetics and Microbiology, College of Medicine, Emerging Pathogens Institute and Institute for Therapeutic Innovation, University of Florida, Gainesville, FL, USA.
| |
Collapse
|
233
|
Individual or Combined Effects of Meropenem, Imipenem, Sulbactam, Colistin, and Tigecycline on Biofilm-Embedded Acinetobacter baumannii and Biofilm Architecture. Antimicrob Agents Chemother 2016; 60:4670-6. [PMID: 27216052 DOI: 10.1128/aac.00551-16] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 05/12/2016] [Indexed: 11/20/2022] Open
Abstract
Acinetobacter baumannii biofilms are difficult to eradicate. We investigated the effects of meropenem (2 mg/liter), imipenem (2 mg/liter), sulbactam (4 mg/liter), colistin (2 mg/liter), and tigecycline (2 mg/liter), alone or in combination, on biofilm-embedded carbapenem-resistant and carbapenem-susceptible A. baumannii (CRAb and CSAb, respectively) cells, as well as on the architecture of the biofilms. A. baumannii ATCC 15151 (Ab15151) and its OXA-82-overproducing transformant, along with two clinical CSAb and two clinical CRAb isolates of differing clonalities, were used. The minimal bactericidal concentrations for biofilm-embedded cells of the six tested isolates were >50-fold those of their planktonic cells. When used individually, meropenem exhibited a higher killing effect than the other four antimicrobials on biofilm-embedded CSAb cells in the colony biofilm assay. For two clinical CRAb isolates, meropenem plus sulbactam or sulbactam plus tigecycline showed >100-fold the bactericidal effect exhibited by these agents used alone after 48 h of treatment. The effect of antimicrobials on the architecture of Ab15151 biofilm emitting green fluorescence was determined by confocal laser scanning microscopy using COMSTAT software. Significant decreases in the maximum biofilm thickness were observed after exposure to meropenem and imipenem. Meropenem plus sulbactam significantly decreased the biomass and mean thickness and increased the roughness coefficient of biofilms, but sulbactam plus tigecycline only decreased the maximum and mean biofilm thickness compared to any of these agents used alone. Meropenem was active against biofilm-embedded CSAb, whereas meropenem plus sulbactam exhibited synergism against biofilm-embedded CRAb and caused significantly more damage to the biofilm architecture than did any of the agents used alone.
Collapse
|
234
|
Satpathy S, Sen SK, Pattanaik S, Raut S. Review on bacterial biofilm: An universal cause of contamination. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2016. [DOI: 10.1016/j.bcab.2016.05.002] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
235
|
Yang X, Sha K, Xu G, Tian H, Wang X, Chen S, Wang Y, Li J, Chen J, Huang N. Subinhibitory Concentrations of Allicin Decrease Uropathogenic Escherichia coli (UPEC) Biofilm Formation, Adhesion Ability, and Swimming Motility. Int J Mol Sci 2016; 17:ijms17070979. [PMID: 27367677 PMCID: PMC4964365 DOI: 10.3390/ijms17070979] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Revised: 06/08/2016] [Accepted: 06/15/2016] [Indexed: 11/16/2022] Open
Abstract
Uropathogenic Escherichia coli (UPEC) biofilm formation enables the organism to avoid the host immune system, resist antibiotics, and provide a reservoir for persistent infection. Once the biofilm is established, eradication of the infection becomes difficult. Therefore, strategies against UPEC biofilm are urgently required. In this study, we investigated the effect of allicin, isolated from garlic essential oil, on UPEC CFT073 and J96 biofilm formation and dispersal, along with its effect on UPEC adhesion ability and swimming motility. Sub-inhibitory concentrations (sub-MICs) of allicin decreased UPEC biofilm formation and affected its architecture. Allicin was also capable of dispersing biofilm. Furthermore, allicin decreased the bacterial adhesion ability and swimming motility, which are important for biofilm formation. Real-time quantitative polymerase chain reaction (RT-qPCR) revealed that allicin decreased the expression of UPEC type 1 fimbriae adhesin gene fimH. Docking studies suggested that allicin was located within the binding pocket of heptyl α-d-mannopyrannoside in FimH and formed hydrogen bonds with Phe1 and Asn135. In addition, allicin decreased the expression of the two-component regulatory systems (TCSs) cognate response regulator gene uvrY and increased the expression of the RNA binding global regulatory protein gene csrA of UPEC CFT073, which is associated with UPEC biofilm. The findings suggest that sub-MICs of allicin are capable of affecting UPEC biofilm formation and dispersal, and decreasing UPEC adhesion ability and swimming motility.
Collapse
Affiliation(s)
- Xiaolong Yang
- Research Unit of Infection and Immunity, Department of Pathophysiology, West China School of Preclinical & Forensic Medicine, Sichuan University, Chengdu 610000, Sichuan, China.
| | - Kaihui Sha
- Research Unit of Infection and Immunity, Department of Pathophysiology, West China School of Preclinical & Forensic Medicine, Sichuan University, Chengdu 610000, Sichuan, China.
| | - Guangya Xu
- Research Unit of Infection and Immunity, Department of Pathophysiology, West China School of Preclinical & Forensic Medicine, Sichuan University, Chengdu 610000, Sichuan, China.
| | - Hanwen Tian
- Research Unit of Infection and Immunity, Department of Pathophysiology, West China School of Preclinical & Forensic Medicine, Sichuan University, Chengdu 610000, Sichuan, China.
| | - Xiaoying Wang
- Research Unit of Infection and Immunity, Department of Pathophysiology, West China School of Preclinical & Forensic Medicine, Sichuan University, Chengdu 610000, Sichuan, China.
| | - Shanze Chen
- Research Unit of Infection and Immunity, Department of Pathophysiology, West China School of Preclinical & Forensic Medicine, Sichuan University, Chengdu 610000, Sichuan, China.
| | - Yi Wang
- Research Unit of Infection and Immunity, Department of Pathophysiology, West China School of Preclinical & Forensic Medicine, Sichuan University, Chengdu 610000, Sichuan, China.
| | - Jingyu Li
- Research Unit of Infection and Immunity, Department of Pathophysiology, West China School of Preclinical & Forensic Medicine, Sichuan University, Chengdu 610000, Sichuan, China.
| | - Junli Chen
- Research Unit of Infection and Immunity, Department of Pathophysiology, West China School of Preclinical & Forensic Medicine, Sichuan University, Chengdu 610000, Sichuan, China.
| | - Ning Huang
- Research Unit of Infection and Immunity, Department of Pathophysiology, West China School of Preclinical & Forensic Medicine, Sichuan University, Chengdu 610000, Sichuan, China.
| |
Collapse
|
236
|
Li W, Yao Z, Sun L, Hu W, Cao J, Lin W, Lin X. Proteomics Analysis Reveals a Potential Antibiotic Cocktail Therapy Strategy for Aeromonas hydrophila Infection in Biofilm. J Proteome Res 2016; 15:1810-20. [DOI: 10.1021/acs.jproteome.5b01127] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
| | | | | | | | - Jijuan Cao
- Liaoning Entry−Exit Inspection and Quarantine Bureau, Dalian 116000, PR China
| | | | | |
Collapse
|
237
|
Kroning IS, Iglesias MA, Sehn CP, Valente Gandra TK, Mata MM, da Silva WP. Staphylococcus aureus isolated from handmade sweets: Biofilm formation, enterotoxigenicity and antimicrobial resistance. Food Microbiol 2016; 58:105-11. [PMID: 27217365 DOI: 10.1016/j.fm.2016.04.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2015] [Revised: 03/17/2016] [Accepted: 04/01/2016] [Indexed: 11/25/2022]
Abstract
Staphylococcus aureus is the second most important pathogen involved in foodborne outbreaks in Brazil. Because of their widespread distribution and biofilm forming ability, handmade sweets are easily contaminated with S. aureus. The aim of this study was to isolate and identify coagulase-positive staphylococci (CPS) from handmade sweets produced in Pelotas City/Brazil. The virulence potential was checked by evaluating the presence of the staphylococcal enterotoxin genes, icaA and icaD genes, the biofilm forming potential and antimicrobial resistance of the isolates. It was find just S. aureus among the CPS isolates. All the S. aureus isolates had biofilm forming ability on stainless steel and more than half of them on polystyrene surfaces. The majority of the isolates carried the icaA (66.6%) and icaD (58.4%) genes and some of them had the genes encoding enterotoxins A (33.4%) and B (16.6%). Furthermore, the majority of the isolates (83%) were resistant to at least one of the tested antimicrobials and multidrug resistance was observed in 8.4% of the isolates. The isolates had virulence potential, and half of them were enterotoxigenic. In addition, the ability of all the isolates to produce biofilms highlights the danger posed by these potentially virulent microorganisms persisting in food manufacturing environments.
Collapse
Affiliation(s)
- Isabela Schneid Kroning
- Science and Agroindustrial Technology Department, Federal University of Pelotas, Pelotas, RS, Brazil.
| | - Mariana Almeida Iglesias
- Biotechnology Unit, Technology Development Center, Federal University of Pelotas, Pelotas, RS, Brazil.
| | | | | | - Marcia Magalhães Mata
- Science and Agroindustrial Technology Department, Federal University of Pelotas, Pelotas, RS, Brazil.
| | - Wladimir Padilha da Silva
- Science and Agroindustrial Technology Department, Federal University of Pelotas, Pelotas, RS, Brazil; Biotechnology Unit, Technology Development Center, Federal University of Pelotas, Pelotas, RS, Brazil.
| |
Collapse
|
238
|
Molina-Manso D, Del-Prado G, Gómez-Barrena E, Cordero-Ampuero J, Fernandez-Roblas R, Esteban J. Effect of different agents with potential antibiofilm activity on antimicrobial susceptibility of biofilms formed by Staphylococcus spp. isolated from implant-related infections. J Antibiot (Tokyo) 2016; 69:686-8. [DOI: 10.1038/ja.2016.9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 12/14/2015] [Accepted: 01/11/2016] [Indexed: 02/06/2023]
|
239
|
Haddad PA, Mah TF, Mussivand T. In Vitro Assessment of Electric Currents Increasing the Effectiveness of Vancomycin Against Staphylococcus epidermidis Biofilms. Artif Organs 2015; 40:804-10. [PMID: 26713750 DOI: 10.1111/aor.12678] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Biofilms are communities of bacteria that can cause infections which are resistant to the immune system and antimicrobial treatments, posing a significant threat for patients with implantable and indwelling medical devices. The purpose of our research was to determine if utilizing specific parameters for electric currents in conjunction with antibiotics could effectively treat a highly resistant biofilm. Our study evaluated the impact of 16 μg/mL of vancomycin with or without 22 or 333 μA of direct electric current (DC) generated by stainless steel electrodes against 24-, 48-, and 72-h-old Staphylococcus epidermidis biofilms formed on titanium coupons. An increase in effectiveness of vancomycin was observed with the combination of 333 μA of electric current against 48-h-old biofilms (P value = 0.01) as well as in combination with 22 μA of electric current against 72-h-old biofilms (P value = 0.04); 333 μA of electric current showed the most significant impact on the effectiveness of vancomycin against S. epidermidis biofilms demonstrating a bioelectric effect previously not observed against this strain of bacteria.
Collapse
Affiliation(s)
- Peter A Haddad
- University of Ottawa, Ottawa, Ontario, Canada.,University of Ottawa Heart Institute, Ottawa, Ontario, Canada.,Medical Devices Innovation Institute, Ottawa, Ontario, Canada
| | | | - Tofy Mussivand
- University of Ottawa, Ottawa, Ontario, Canada.,University of Ottawa Heart Institute, Ottawa, Ontario, Canada.,Medical Devices Innovation Institute, Ottawa, Ontario, Canada
| |
Collapse
|
240
|
Antibiotic regimen based on population analysis of residing persister cells eradicates Staphylococcus epidermidis biofilms. Sci Rep 2015; 5:18578. [PMID: 26687035 PMCID: PMC4685274 DOI: 10.1038/srep18578] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 11/20/2015] [Indexed: 12/21/2022] Open
Abstract
Biofilm formation is a major pathogenicity strategy of Staphylococcus epidermidis causing various medical-device infections. Persister cells have been implicated in treatment failure of such infections. We sought to profile bacterial subpopulations residing in S. epidermidis biofilms, and to establish persister-targeting treatment strategies to eradicate biofilms. Population analysis was performed by challenging single biofilm cells with antibiotics at increasing concentrations ranging from planktonic minimum bactericidal concentrations (MBCs) to biofilm MBCs (MBCbiofilm). Two populations of “persister cells” were observed: bacteria that survived antibiotics at MBCbiofilm for 24/48 hours were referred to as dormant cells; those selected with antibiotics at 8 X MICs for 3 hours (excluding dormant cells) were defined as tolerant-but-killable (TBK) cells. Antibiotic regimens targeting dormant cells were tested in vitro for their efficacies in eradicating persister cells and intact biofilms. This study confirmed that there are at least three subpopulations within a S. epidermidis biofilm: normal cells, dormant cells, and TBK cells. Biofilms comprise more TBK cells and dormant cells than their log-planktonic counterparts. Using antibiotic regimens targeting dormant cells, i.e. effective antibiotics at MBCbiofilm for an extended period, might eradicate S. epidermidis biofilms. Potential uses for this strategy are in antibiotic lock techniques and inhaled aerosolized antibiotics.
Collapse
|
241
|
Acinetobacter baumannii Is Dependent on the Type II Secretion System and Its Substrate LipA for Lipid Utilization and In Vivo Fitness. J Bacteriol 2015; 198:711-9. [PMID: 26668261 DOI: 10.1128/jb.00622-15] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 12/01/2015] [Indexed: 12/21/2022] Open
Abstract
UNLABELLED Gram-negative bacteria express a number of sophisticated secretion systems to transport virulence factors across the cell envelope, including the type II secretion (T2S) system. Genes for the T2S components GspC through GspN and PilD are conserved among isolates of Acinetobacter baumannii, an increasingly common nosocomial pathogen that is developing multidrug resistance at an alarming rate. In contrast to most species, however, the T2S genes are dispersed throughout the genome rather than linked into one or two operons. Despite this unique genetic organization, we show here that the A. baumannii T2S system is functional. Deletion of gspD or gspE in A. baumannii ATCC 17978 results in loss of secretion of LipA, a lipase that breaks down long-chain fatty acids. Due to a lack of extracellular lipase, the gspD mutant, the gspE mutant, and a lipA deletion strain are incapable of growth on long-chain fatty acids as a sole source of carbon, while their growth characteristics are indistinguishable from those of the wild-type strain in nutrient-rich broth. Genetic inactivation of the T2S system and its substrate, LipA, also has a negative impact on in vivo fitness in a neutropenic murine model for bacteremia. Both the gspD and lipA mutants are outcompeted by the wild-type strain as judged by their reduced numbers in spleen and liver following intravenous coinoculation. Collectively, our findings suggest that the T2S system plays a hitherto-unrecognized role in in vivo survival of A. baumannii by transporting a lipase that may contribute to fatty acid metabolism. IMPORTANCE Infections by multidrug-resistant Acinetobacter baumannii are a growing health concern worldwide, underscoring the need for a better understanding of the molecular mechanisms by which this pathogen causes disease. In this study, we demonstrated that A. baumannii expresses a functional type II secretion (T2S) system that is responsible for secretion of LipA, an extracellular lipase required for utilization of exogenously added lipids. The T2S system and the secreted lipase support in vivo colonization and thus contribute to the pathogenic potential of A. baumannii.
Collapse
|
242
|
Zhang WH, Ren SQ, Gu XX, Li W, Yang L, Zeng ZL, Liu YH, Jiang HX. High frequency of virulence genes among Escherichia coli with the bla CTX-M genotype from diarrheic piglets in China. Vet Microbiol 2015; 180:260-7. [DOI: 10.1016/j.vetmic.2015.08.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 08/12/2015] [Accepted: 08/26/2015] [Indexed: 02/06/2023]
|
243
|
Peralta MA, da Silva MA, Ortega MG, Cabrera JL, Paraje MG. Antifungal activity of a prenylated flavonoid from Dalea elegans against Candida albicans biofilms. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2015; 22:975-980. [PMID: 26407939 DOI: 10.1016/j.phymed.2015.07.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Revised: 06/19/2015] [Accepted: 07/04/2015] [Indexed: 06/05/2023]
Abstract
BACKGROUND The continuing emergence of infections with antifungal resistant Candida strains requires a constant search for new antifungal drugs, with the plant kingdom being an important source of chemical structures. PURPOSE The present study investigated the antifungal effect of 2',4'-dihydroxy-5'-(1''',1'''-dimethylallyl)-8-prenylpinocembrin (8PP, formerly 6PP), a natural prenylflavonoid, on Candida albicans biofilms, and compared this with an azole antifungal (fluconazole) by studying the cellular stress and antioxidant response. STUDY DESIGN/METHODS The fluconazole sensitive (SCa) and azole-resistant (RCa) C. albicans strains were used, with biofilm formation being studied using crystal violet (CV) and confocal scanning laser microscopy (CSLM). The minimal inhibitory concentration for sessile cells (SMIC) was defined as the concentration of antifungal that caused a 50% (SMIC 50) and 80% (SMIC 80) reduction of treated biofilms. The reactive oxygen species (ROS) were detected by the reduction of nitro blue tetrazolium (NBT), and reactive nitrogen intermediates (RNI) were determined by the Griess assay. The activities of the superoxide dismutase (SOD) and catalase (CAT) antioxidant enzymes and the total antioxidant capacity of the biofilms were measured by spectrophotometric methods. ROS accumulation was also detected inside biofilms by using the fluorogenic dye 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA), which was visualized by CSLM. RESULTS The SCa and RCa biofilms were strongly inhibited by 8PP at 100 µM (SMIC 80). We observed that cellular stress affected biofilms growth, resulting in an increase of ROS and also of reactive nitrogen intermediates (RNI), with SOD and CAT being increased significantly in the presence of 8PP. The basal level of the biofilm total antioxidant capacity was higher in RCa than SCa. Moreover, in SCa, the total antioxidant capacity rose considerably in the presence of both 8PP and fluconazole. CONCLUSION Our data suggest that 8PP may be useful for the treatment of biofilm-related Candida infections, through an accumulation of endogenous ROS and RNI that can induce an adaptive response based on a coordinated increase in antioxidant defenses. 8PP may also have a therapeutic potential in C. albicans infections.
Collapse
Affiliation(s)
- Mariana Andrea Peralta
- Departamento de Farmacia, Facultad de Ciencias Químicas, Instituto Multidisciplinario de Biología Vegetal (IMBIV) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, 5000 Córdoba, Argentina
| | - María Angel da Silva
- Facultad de Ciencias Exactas Físicas y Naturales, Instituto Multidisciplinario de Biología Vegetal (IMBIV) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Cátedra de Microbiología, Universidad Nacional de Córdoba, Av. Vélez Sarsfield 299, Córdoba, Argentina
| | - María Gabriela Ortega
- Departamento de Farmacia, Facultad de Ciencias Químicas, Instituto Multidisciplinario de Biología Vegetal (IMBIV) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, 5000 Córdoba, Argentina
| | - José Luis Cabrera
- Departamento de Farmacia, Facultad de Ciencias Químicas, Instituto Multidisciplinario de Biología Vegetal (IMBIV) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, 5000 Córdoba, Argentina
| | - María Gabriela Paraje
- Facultad de Ciencias Exactas Físicas y Naturales, Instituto Multidisciplinario de Biología Vegetal (IMBIV) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET); Cátedra de Microbiología, Universidad Nacional de Córdoba, Av. Vélez Sarsfield 299, Córdoba, Argentina.
| |
Collapse
|
244
|
Warner CJA, Cheng AT, Yildiz FH, Linington RG. Development of benzo[1,4]oxazines as biofilm inhibitors and dispersal agents against Vibrio cholerae. Chem Commun (Camb) 2015; 51:1305-8. [PMID: 25479128 PMCID: PMC4288701 DOI: 10.1039/c4cc07003h] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Synthesis of a library of natural product-inspired biofilm inhibitors has revealed a compound with selective and potent anti-biofilm activity against V. cholerae.
Bacterial biofilms are estimated to be associated with over 65 percent of all nosocomial infections. However, no therapeutics have been approved by the FDA which directly mediate biofilm formation or persistence. Herein we report oxazine 25 as a highly potent inhibitor, disperser and in the presence of the appropriate antibiotic eradicator of V. cholerae biofilms.
Collapse
Affiliation(s)
- Christopher J A Warner
- Department of Chemistry and Biochemistry, University of California Santa Cruz, California, 95064, USA.
| | | | | | | |
Collapse
|
245
|
Mittal R, Lisi CV, Gerring R, Mittal J, Mathee K, Narasimhan G, Azad RK, Yao Q, Grati M, Yan D, Eshraghi AA, Angeli SI, Telischi FF, Liu XZ. Current concepts in the pathogenesis and treatment of chronic suppurative otitis media. J Med Microbiol 2015; 64:1103-1116. [PMID: 26248613 DOI: 10.1099/jmm.0.000155] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Otitis media (OM) is an inflammation of the middle ear associated with infection. Despite appropriate therapy, acute OM (AOM) can progress to chronic suppurative OM (CSOM) associated with ear drum perforation and purulent discharge. The effusion prevents the middle ear ossicles from properly relaying sound vibrations from the ear drum to the oval window of the inner ear, causing conductive hearing loss. In addition, the inflammatory mediators generated during CSOM can penetrate into the inner ear through the round window. This can cause the loss of hair cells in the cochlea, leading to sensorineural hearing loss. Pseudomonas aeruginosa and Staphylococcus aureus are the most predominant pathogens that cause CSOM. Although the pathogenesis of AOM is well studied, very limited research is available in relation to CSOM. With the emergence of antibiotic resistance as well as the ototoxicity of antibiotics and the potential risks of surgery, there is an urgent need to develop effective therapeutic strategies against CSOM. This warrants understanding the role of host immunity in CSOM and how the bacteria evade these potent immune responses. Understanding the molecular mechanisms leading to CSOM will help in designing novel treatment modalities against the disease and hence preventing the hearing loss.
Collapse
Affiliation(s)
- Rahul Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Christopher V Lisi
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Robert Gerring
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Jeenu Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Kalai Mathee
- Department of Human and Molecular Genetics, Herbert Wertheim College of Medicine, Florida International University, Miami, FL, USA
| | - Giri Narasimhan
- Bioinformatics Research Group (BioRG), School of Computing and Information Sciences, Florida International University, Miami, FL, USA
| | - Rajeev K Azad
- Department of Biological Sciences and Mathematics, University of North Texas, Denton, TX, USA
| | - Qi Yao
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - M'hamed Grati
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Denise Yan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Adrien A Eshraghi
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Simon I Angeli
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Fred F Telischi
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Xue-Zhong Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| |
Collapse
|
246
|
Shousha A, Awaiwanont N, Sofka D, Smulders FJM, Paulsen P, Szostak MP, Humphrey T, Hilbert F. Bacteriophages Isolated from Chicken Meat and the Horizontal Transfer of Antimicrobial Resistance Genes. Appl Environ Microbiol 2015; 81:4600-6. [PMID: 25934615 PMCID: PMC4551174 DOI: 10.1128/aem.00872-15] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 04/22/2015] [Indexed: 02/07/2023] Open
Abstract
Antimicrobial resistance in microbes poses a global and increasing threat to public health. The horizontal transfer of antimicrobial resistance genes was thought to be due largely to conjugative plasmids or transposons, with only a minor part being played by transduction through bacteriophages. However, whole-genome sequencing has recently shown that the latter mechanism could be highly important in the exchange of antimicrobial resistance genes between microorganisms and environments. The transfer of antimicrobial resistance genes by phages could underlie the origin of resistant bacteria found in food. We show that chicken meat carries a number of phages capable of transferring antimicrobial resistance. Of 243 phages randomly isolated from chicken meat, about a quarter (24.7%) were able to transduce resistance to one or more of the five antimicrobials tested into Escherichia coli ATCC 13706 (DSM 12242). Resistance to kanamycin was transduced the most often, followed by that to chloramphenicol, with four phages transducing tetracycline resistance and three transducing ampicillin resistance. Phages able to transduce antimicrobial resistance were isolated from 44% of the samples of chicken meat that we tested. The statistically significant (P = 0.01) relationship between the presence of phages transducing kanamycin resistance and E. coli isolates resistant to this antibiotic suggests that transduction may be an important mechanism for transferring kanamycin resistance to E. coli. It appears that the transduction of resistance to certain antimicrobials, e.g., kanamycin, not only is widely distributed in E. coli isolates found on meat but also could represent a major mechanism for resistance transfer. The result is of high importance for animal and human health.
Collapse
Affiliation(s)
- Amira Shousha
- Institute of Meat Hygiene, Meat Technology and Food Science, University of Veterinary Medicine, Vienna, Austria
| | - Nattakarn Awaiwanont
- Institute of Meat Hygiene, Meat Technology and Food Science, University of Veterinary Medicine, Vienna, Austria
| | - Dmitrij Sofka
- Institute of Meat Hygiene, Meat Technology and Food Science, University of Veterinary Medicine, Vienna, Austria
| | - Frans J M Smulders
- Institute of Meat Hygiene, Meat Technology and Food Science, University of Veterinary Medicine, Vienna, Austria
| | - Peter Paulsen
- Institute of Meat Hygiene, Meat Technology and Food Science, University of Veterinary Medicine, Vienna, Austria
| | - Michael P Szostak
- Institute of Microbiology, University of Veterinary Medicine, Vienna, Austria
| | - Tom Humphrey
- Medical Microbiology and Infectious Diseases Group, College of Medicine, Swansea University, Swansea, Wales, United Kingdom
| | - Friederike Hilbert
- Institute of Meat Hygiene, Meat Technology and Food Science, University of Veterinary Medicine, Vienna, Austria
| |
Collapse
|
247
|
Frank KL, Vergidis P, Brinkman CL, Greenwood Quaintance KE, Barnes AMT, Mandrekar JN, Schlievert PM, Dunny GM, Patel R. Evaluation of the Enterococcus faecalis Biofilm-Associated Virulence Factors AhrC and Eep in Rat Foreign Body Osteomyelitis and In Vitro Biofilm-Associated Antimicrobial Resistance. PLoS One 2015; 10:e0130187. [PMID: 26076451 PMCID: PMC4467866 DOI: 10.1371/journal.pone.0130187] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 05/18/2015] [Indexed: 02/01/2023] Open
Abstract
Enterococcus faecalis can cause healthcare-associated biofilm infections, including those of orthopedic devices. Treatment of enterococcal prosthetic joint infection is difficult, in part, due to biofilm-associated antimicrobial resistance. We previously showed that the E. faecalis OG1RF genes ahrC and eep are in vitro biofilm determinants and virulence factors in animal models of endocarditis and catheter-associated urinary tract infection. In this study, we evaluated the role of these genes in a rat acute foreign body osteomyelitis model and in in vitro biofilm-associated antimicrobial resistance. Osteomyelitis was established for one week following the implantation of stainless steel orthopedic wires inoculated with E. faecalis strains OG1RF, ΩahrC, and ∆eep into the proximal tibiae of rats. The median bacterial loads recovered from bones and wires did not differ significantly between the strains at multiple inoculum concentrations. We hypothesize that factors present at the infection site that affect biofilm formation, such as the presence or absence of shear force, may account for the differences in attenuation in the various animal models we have used to study the ΩahrC and ∆eep strains. No differences among the three strains were observed in the planktonic and biofilm antimicrobial susceptibilities to ampicillin, vancomycin, daptomycin, linezolid, and tetracycline. These findings suggest that neither ahrC nor eep directly contribute to E. faecalis biofilm-associated antimicrobial resistance. Notably, the experimental evidence that the biofilm attachment mutant ΩahrC displays biofilm-associated antimicrobial resistance suggests that surface colonization alone is sufficient for E. faecalis cells to acquire the biofilm antimicrobial resistance phenotype.
Collapse
Affiliation(s)
- Kristi L. Frank
- Department of Microbiology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Paschalis Vergidis
- Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Cassandra L. Brinkman
- Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Kerryl E. Greenwood Quaintance
- Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Aaron M. T. Barnes
- Department of Microbiology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Jayawant N. Mandrekar
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Patrick M. Schlievert
- Department of Microbiology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Gary M. Dunny
- Department of Microbiology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Robin Patel
- Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, United States of America
- Division of Infectious Diseases, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail:
| |
Collapse
|
248
|
Dharmaprakash A, Thandavarayan R, Joseph I, Thomas S. Development of broad-spectrum antibiofilm drugs: strategies and challenges. Future Microbiol 2015; 10:1035-48. [DOI: 10.2217/fmb.15.14] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
ABSTRACT The severity of many chronic bacterial infections is mainly due to the biofilm mode of life adapted by pathogenic bacteria. The bacteria in biofilm-stage exhibit high resistance to host immune responses and antimicrobials, which complicates the treatment process and results in life threatening conditions. Most of the chronic infections are polymicrobial in nature. In order to combat the polymicrobial biofilm infections and to increase the efficiency of antimicrobials, there is an urgent need for broad-spectrum antibiofilm drugs. This review discusses the clinical needs and current status of broad-spectrum antibiofilm drugs with special emphasis on prospective strategies and hurdles in the process of new drug discovery.
Collapse
Affiliation(s)
- Akhilandeswarre Dharmaprakash
- Cholera & Biofilm Research Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram – 695 014, Kerala, India
| | | | - Iype Joseph
- Pathogen Biology Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram – 695 014, Kerala, India
| | - Sabu Thomas
- Cholera & Biofilm Research Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram – 695 014, Kerala, India
| |
Collapse
|
249
|
Statins and Antimicrobial Effects: Simvastatin as a Potential Drug against Staphylococcus aureus Biofilm. PLoS One 2015; 10:e0128098. [PMID: 26020797 PMCID: PMC4447369 DOI: 10.1371/journal.pone.0128098] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 04/23/2015] [Indexed: 12/11/2022] Open
Abstract
Statins are important lipid-lowering agents with other pleiotropic effects. Several studies have explored a possible protective effect of statins to reduce the morbidity and mortality of many infectious diseases. Staphylococcus aureus is one of the main pathogens implicated in nosocomial infections; its ability to form biofilms makes treatment difficult. The present study observed the MIC of atorvastatin, pravastatin and simvastatin against S. aureus, Pseudomonas aeruginosa, Escherichia coli and Enterococcus faecalis. Simvastatin was the only agent with activity against clinical isolates and reference strains of methicilin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA). Thus, the effects of simvastatin on the growth, viability and biofilm formation of S. aureus were tested. In addition, a possible synergistic effect between simvastatin and vancomycin was evaluated. Simvastatin’s MIC was 15.65 µg/mL for S. aureus 29213 and 31.25 µg/mL for the other strains of S. aureus. The effect of simvastatin was bactericidal at 4xMIC and bacteriostatic at the MIC concentration. No synergistic effect was found between simvastatin and vancomycin. However, the results obtained against S. aureus biofilms showed that, in addition to inhibiting adhesion and biofilm formation at concentrations from 1/16xMIC to 4xMIC, simvastatin was also able to act against mature biofilms, reducing cell viability and extra-polysaccharide production. In conclusion, simvastatin showed pronounced antimicrobial activity against S. aureus biofilms, reducing their formation and viability.
Collapse
|
250
|
Ghasemian A, Najar Peerayeh S, Bakhshi B, Mirzaee M. Several Virulence Factors of Multidrug-Resistant Staphylococcus aureus Isolates From Hospitalized Patients in Tehran. INTERNATIONAL JOURNAL OF ENTERIC PATHOGENS 2015. [DOI: 10.17795/ijep25196] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|