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Alrouji M, Kuriri FA, Alqasmi MH, AlSudais H, Alissa M, Alsuwat MA, Asad M, Joseph B, Almuhanna Y. A Simple In-Vivo Method for Evaluation of Antibiofilm and Wound Healing Activity Using Excision Wound Model in Diabetic Swiss Albino Mice. Microorganisms 2023; 11:microorganisms11030692. [PMID: 36985266 PMCID: PMC10051147 DOI: 10.3390/microorganisms11030692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 02/27/2023] [Accepted: 03/07/2023] [Indexed: 03/30/2023] Open
Abstract
The study developed a simple and inexpensive method to induce biofilm formation in-vivo for the evaluation of the antibiofilm activity of pharmacological agents using Swiss albino mice. Animals were made diabetic using streptozocin and nicotinamide. A cover slip containing preformed biofilm along with MRSA culture was introduced into the excision wound in these animals. The method was effective in developing biofilm on the coverslip after 24 h incubation in MRSA broth which was confirmed by microscopic examination and a crystal violet assay. Application of preformed biofilm along with microbial culture induced a profound infection with biofilm formation on excision wounds in 72 h. This was confirmed by macroscopic, histological, and bacterial load determination. Mupirocin, a known antibacterial agent effective against MRSA was used to demonstrate antibiofilm activity. Mupirocin was able to completely heal the excised wounds in 19 to 21 days while in the base-treated group, healing took place between 30 and 35 days. The method described is robust and can be reproduced easily without the use of transgenic animals and sophisticated methods such as confocal microscopy.
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Affiliation(s)
- Mohammed Alrouji
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Shaqra University, Shaqra 11961, Saudi Arabia
| | - Fahd A Kuriri
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Shaqra University, Shaqra 11961, Saudi Arabia
| | - Mohammed Hussein Alqasmi
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Shaqra University, Shaqra 11961, Saudi Arabia
| | - Hamood AlSudais
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Saud University, Riyadh 12372, Saudi Arabia
| | - Mohammed Alissa
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia
| | - Meshari A Alsuwat
- Clinical Laboratory Sciences Department, College of Applied Medical Sciences, Taif University, Al-Taif 21974, Saudi Arabia
| | - Mohammed Asad
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Shaqra University, Shaqra 11961, Saudi Arabia
| | - Babu Joseph
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Shaqra University, Shaqra 11961, Saudi Arabia
| | - Yasir Almuhanna
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Shaqra University, Shaqra 11961, Saudi Arabia
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Pseudomonas aeruginosa and Staphylococcus aureus Display Differential Proteomic Responses to the Silver(I) Compound, SBC3. Antibiotics (Basel) 2023; 12:antibiotics12020348. [PMID: 36830259 PMCID: PMC9952281 DOI: 10.3390/antibiotics12020348] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 01/27/2023] [Accepted: 02/03/2023] [Indexed: 02/10/2023] Open
Abstract
The urgent need to combat antibiotic resistance and develop novel antimicrobial therapies has triggered studies on novel metal-based formulations. N-heterocyclic carbene (NHC) complexes coordinate transition metals to generate a broad range of anticancer and/or antimicrobial agents, with ongoing efforts being made to enhance the lipophilicity and drug stability. The lead silver(I) acetate complex, 1,3-dibenzyl-4,5-diphenylimidazol-2-ylidene (NHC*) (SBC3), has previously demonstrated promising growth and biofilm-inhibiting properties. In this work, the responses of two structurally different bacteria to SBC3 using label-free quantitative proteomics were characterised. Multidrug-resistant Pseudomonas aeruginosa (Gram-negative) and Staphylococcus aureus (Gram-positive) are associated with cystic fibrosis lung colonisation and chronic wound infections, respectively. SBC3 increased the abundance of alginate biosynthesis, the secretion system and drug detoxification proteins in P. aeruginosa, whilst a variety of pathways, including anaerobic respiration, twitching motility and ABC transport, were decreased in abundance. This contrasted the affected pathways in S. aureus, where increased DNA replication/repair and cell redox homeostasis and decreased protein synthesis, lipoylation and glucose metabolism were observed. Increased abundance of cell wall/membrane proteins was indicative of the structural damage induced by SBC3 in both bacteria. These findings show the potential broad applications of SBC3 in treating Gram-positive and Gram-negative bacteria.
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Characterization of Uropathogenic Pseudomonas aeruginosa: Serotypes, Resistance Phenotypes, and Virulence Genotypes. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2022. [DOI: 10.22207/jpam.16.2.57] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas aeruginosa is a major cause of urinary tract infections. This organism has extended resistance to antimicrobials along with multiple virulence factors, making it difficult to treat. In this study, 49 isolates from urine samples were identified as P. aeruginosa and serotyped by the slide agglutination method. The sensitivity of isolates against 10 antipseudomonal drugs was determined. Phenotypically, lipase, protease, hemolysin, and biofilm production were detected. Genes for the type III secretion system, elastase B, and exotoxin A were detected by PCR. Serotype O11 was the most predominant serotype among test isolates. High levels of resistance were observed against ceftazidime, cefepime, piperacillin, and piperacillin/tazobactam while 10.2% of isolates were resistant to amikacin. MDR was detected in 20.4% of the isolates and was significantly associated with strong biofilm producers. About 95.9% and 63.3% of P. aeruginosa isolates had proteolytic and lipolytic activity, respectively. Among the genes detected, the exoY gene was the most prevalent gene (79.6%), while the exoU gene was the least frequent one (10.2%). toxA and lasB genes were amplified in 63.27% and 75.5% of the isolates, respectively. In addition, the exoU gene was significantly associated with MDR isolates. The high incidence of exoS, exoT, exoY, lasB, and toxA genes in uropathogenic P. aeruginosa implies that these genes can be considered markers for virulent isolates. Furthermore, the coexistence of exoU and exoS genes, even in 6% of isolates, poses a significant treatment challenge because those isolates possess both the invasive and cytotoxic properties of both effector proteins.
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Honarmand T, Sharif AP, Salehzadeh A, Jalali A, Nikokar I. Does Conjugation of Silver Nanoparticles with Thiosemicarbazide Increase Their Antibacterial Properties? Microb Drug Resist 2022; 28:293-305. [PMID: 35005985 DOI: 10.1089/mdr.2020.0557] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The opportunistic pathogen, Pseudomonas aeruginosa, uses different mechanisms as well as biofilm production to acquire antibiotic resistance. The polysaccharide synthesis locus (psl) genes play an important role in P. aeruginosa biofilm formation. Therefore, targeting the expression of psl genes can be a suitable strategy to prevent the formation of biofilms by antibiotic-resistant strains. Today, advances in nanotechnology provide a novel potential strategy to combat antibiotic-resistant bacteria. In this study, the silver nanoparticles (Ag NPs) synthesized using a chemical co-precipitation method and, after conjugation with thiosemicarbazide, their effect on the biofilm-forming ability are studied in P. aeruginosa isolates. Chemical properties of synthesized nanoparticles were determined by scanning and transmission electron microscopy, Fourier transform infrared spectroscopy, diffuse reflectance spectroscopy, ultraviolet-visible spectroscopy, X-ray diffraction, and energy dispersive X-ray spectroscopy. The results confirmed the spherical/cubic morphology, solution stability, and good dispersion of Ag@Glu-TSC NPs with an average size of 40-60 nm. In addition, minimum inhibitory concentration values of functionalized Ag NPs were at least twofold lower than the Ag NPs (alone). The quantitative PCR data analysis showed a decrease in the expression of the pslA gene in the presence of Ag@Glu-TSC NPs, up to 60%, which was associated with a reduction of biofilm formation compared to control. In conclusion, the Ag@Glu-TSC NPs can be considered a new inhibitor of biofilm production in antibiotic-resistant bacteria.
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Affiliation(s)
- Tayebeh Honarmand
- Department of Biology, Rasht Branch, Islamic Azad University, Rasht, Iran
| | - Ardalan Panahi Sharif
- Department of Medical Sciences, Faculty of Medicine, Ondokuz Mayis University, Samsun, Turkey
| | - Ali Salehzadeh
- Department of Biology, Rasht Branch, Islamic Azad University, Rasht, Iran
| | - Amir Jalali
- Department of Biology, Faculty of Sciences, Arak University, Arak, Iran
| | - Iraj Nikokar
- Department of Microbiology, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
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Bai X, Nakatsu CH, Bhunia AK. Bacterial Biofilms and Their Implications in Pathogenesis and Food Safety. Foods 2021; 10:2117. [PMID: 34574227 PMCID: PMC8472614 DOI: 10.3390/foods10092117] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 08/21/2021] [Accepted: 08/30/2021] [Indexed: 12/28/2022] Open
Abstract
Biofilm formation is an integral part of the microbial life cycle in nature. In food processing environments, bacterial transmissions occur primarily through raw or undercooked foods and by cross-contamination during unsanitary food preparation practices. Foodborne pathogens form biofilms as a survival strategy in various unfavorable environments, which also become a frequent source of recurrent contamination and outbreaks of foodborne illness. Instead of focusing on bacterial biofilm formation and their pathogenicity individually, this review discusses on a molecular level how these two physiological processes are connected in several common foodborne pathogens such as Listeria monocytogenes, Staphylococcus aureus, Salmonella enterica and Escherichia coli. In addition, biofilm formation by Pseudomonas aeruginosa is discussed because it aids the persistence of many foodborne pathogens forming polymicrobial biofilms on food contact surfaces, thus significantly elevating food safety and public health concerns. Furthermore, in-depth analyses of several bacterial molecules with dual functions in biofilm formation and pathogenicity are highlighted.
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Affiliation(s)
- Xingjian Bai
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN 47907, USA;
| | - Cindy H. Nakatsu
- Department of Agronomy, Purdue University, West Lafayette, IN 47907, USA;
- Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN 47907, USA
| | - Arun K. Bhunia
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN 47907, USA;
- Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN 47907, USA
- Department of Comparative Pathobiology, Purdue University, West Lafayette, IN 47907, USA
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Rizzato C, Torres J, Kasamatsu E, Camorlinga-Ponce M, Bravo MM, Canzian F, Kato I. Potential Role of Biofilm Formation in the Development of Digestive Tract Cancer With Special Reference to Helicobacter pylori Infection. Front Microbiol 2019; 10:846. [PMID: 31110496 PMCID: PMC6501431 DOI: 10.3389/fmicb.2019.00846] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 04/02/2019] [Indexed: 12/16/2022] Open
Abstract
Bacteria are highly social organisms that communicate via signaling molecules and can assume a multicellular lifestyle to build biofilm communities. Until recently, complications from biofilm-associated infection have been primarily ascribed to increased bacterial resistance to antibiotics and host immune evasion, leading to persistent infection. In this theory and hypothesis article we present a relatively new argument that biofilm formation has potential etiological role in the development of digestive tract cancer. First, we summarize recent new findings suggesting the potential link between bacterial biofilm and various types of cancer to build the foundation of our hypothesis. To date, evidence has been particularly convincing for colorectal cancer and its precursor, i.e., polyps, pointing to several key individual bacterial species, such as Bacteroides fragilis, Fusobacterium nucleatum, and Streptococcus gallolyticus subsp. Gallolyticus. Then, we further extend this hypothesis to one of the most common bacterial infection in humans, Helicobacter pylori (Hp), which is considered a major cause of gastric cancer. Thus far, there has been no direct evidence linking in vivo Hp gastric biofilm formation to gastric carcinogenesis. Yet, we synthesize the information to support an argument that biofilm associated-Hp is potentially more carcinogenic, summarizing biological characteristics of biofilm-associated bacteria. We also discuss mechanistic pathways as to how Hp or other biofilm-associated bacteria control biofilm formation and highlight recent findings on Hp genes that influence biofilm formation, which may lead to strain variability in biofilm formation. This knowledge may open a possibility of developing targeted intervention. We conclude, however, that this field is still in its infancy. To test the hypothesis rigorously and to link it ultimately to gastric pathologies (e.g., premalignant lesions and cancer), studies are needed to learn more about Hp biofilms, such as compositions and biological properties of extracellular polymeric substance (EPS), presence of non-Hp microbiome and geographical distribution of biofilms in relation to gastric gland types and structures. Identification of specific Hp strains with enhanced biofilm formation would be helpful not only for screening patients at high risk for sequelae from Hp infection, but also for development of new antibiotics to avoid resistance, regardless of its association with gastric cancer.
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Affiliation(s)
- Cosmeri Rizzato
- Department of Translation Research and of New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Javier Torres
- Unidad de Investigación en Enfermedades Infecciosas, Unidades Médicas de Alta Especialidad Pediatría, Instituto Mexicano del Seguro Social, Mexico City, Mexico
| | - Elena Kasamatsu
- Instituto de Investigaciones en Ciencias de la Salud, National University of Asunción, Asunción, Paraguay
| | - Margarita Camorlinga-Ponce
- Unidad de Investigación en Enfermedades Infecciosas, Unidades Médicas de Alta Especialidad Pediatría, Instituto Mexicano del Seguro Social, Mexico City, Mexico
| | - Maria Mercedes Bravo
- Grupo de Investigación en Biología del Cáncer, Instituto Nacional de Cancerología, Bogotá, Colombia
| | - Federico Canzian
- Genomic Epidemiology Group, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Ikuko Kato
- Department of Oncology and Pathology, Wayne State University School of Medicine, Detroit, MI, United States
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7
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Brill FHH, Gabriel H, Brill H, Klock JH, Steinmann J, Arndt A. Decolonization potential of 0.02% polyhexanide irrigation solution in urethral catheters under practice-like in vitro conditions. BMC Urol 2018; 18:49. [PMID: 29793457 PMCID: PMC5968594 DOI: 10.1186/s12894-018-0362-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 05/11/2018] [Indexed: 12/02/2022] Open
Abstract
Background Long-term use of indwelling urethral catheters is associated with high risk of urinary tract infection (UTI) and blockage, which may in turn cause significant morbidity and reduce the life of the catheter. A 0.02% polyhexanide irrigation solution has been developed for routine mechanical rinsing together with bacterial decolonization of suprapubic and indwelling urethral catheters. Methods Using a practice-like in vitro assay and standard silicon catheters, artificially contaminated with clinically relevant bacteria, experiments were carried out to evaluate the bacterial decolonization potential of polyhexanide vs. 1) no intervention (standard approach) and 2) irrigation with a saline (NaCl 0.9%) solution. Swabbing and irrigation was used to extract the bacteria. Results Irrigation with polyhexanide reduced the microbial population vs. the control catheters by a factor of 1.64 log10 (swab extraction) and by a factor of 2.56 log10 (membrane filtration). The difference in mean microbial counts between the two groups (0.90) was statistically significant in favor of polyhexanide when the liquid extraction method was used (p = 0.034). The difference between the two groups using the swab extraction method did not reach statistical significance. Conclusions The saline and polyhexanide solutions are able to reduce bacterial load of catheters, which shows a combined mechanical and antimicrobial effect. Further research is required to evaluate the long-term tolerability and efficacy of polyhexanide in clinical practice.
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Affiliation(s)
- Florian H H Brill
- Dr. Brill + Partner GmbH Institute for Hygiene and Microbiology, Stiegstück 34, 22339, Hamburg, Germany.
| | - Henrik Gabriel
- Dr. Brill + Partner GmbH Institute for Hygiene and Microbiology, Stiegstück 34, 22339, Hamburg, Germany
| | - Holger Brill
- Dr. Brill + Partner GmbH Institute for Hygiene and Microbiology, Stiegstück 34, 22339, Hamburg, Germany
| | - Jan-Hendrik Klock
- Dr. Brill + Partner GmbH Institute for Hygiene and Microbiology, Stiegstück 34, 22339, Hamburg, Germany
| | - Joerg Steinmann
- Institute of Medical Microbiology, University Hospital Essen, Essen, Germany.,Institute of Clinical Hygiene, Medical Microbiology and Infectiology, Paracelsus Medical University, Klinikum Nürnberg, Nuremberg, Germany
| | - Andreas Arndt
- Department of Research and Development, B. Braun Medical Ltd., Sempach, Switzerland
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8
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Azevedo AS, Almeida C, Melo LF, Azevedo NF. Impact of polymicrobial biofilms in catheter-associated urinary tract infections. Crit Rev Microbiol 2016; 43:423-439. [PMID: 28033847 DOI: 10.1080/1040841x.2016.1240656] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Recent reports have demonstrated that most biofilms involved in catheter-associated urinary tract infections are polymicrobial communities, with pathogenic microorganisms (e.g. Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae) and uncommon microorganisms (e.g. Delftia tsuruhatensis, Achromobacter xylosoxidans) frequently co-inhabiting the same urinary catheter. However, little is known about the interactions that occur between different microorganisms and how they impact biofilm formation and infection outcome. This lack of knowledge affects CAUTIs management as uncommon bacteria action can, for instance, influence the rate at which pathogens adhere and grow, as well as affect the overall biofilm resistance to antibiotics. Another relevant aspect is the understanding of factors that drive a single pathogenic bacterium to become prevalent in a polymicrobial community and subsequently cause infection. In this review, a general overview about the IMDs-associated biofilm infections is provided, with an emphasis on the pathophysiology and the microbiome composition of CAUTIs. Based on the available literature, it is clear that more research about the microbiome interaction, mechanisms of biofilm formation and of antimicrobial tolerance of the polymicrobial consortium are required to better understand and treat these infections.
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Affiliation(s)
- Andreia S Azevedo
- a Department of Chemical Engineering, Faculty of Engineering , Laboratory for Process Engineering, Environment, and Energy and Biotechnology Engineering (LEPABE), University of Porto , Porto , Portugal
| | - Carina Almeida
- a Department of Chemical Engineering, Faculty of Engineering , Laboratory for Process Engineering, Environment, and Energy and Biotechnology Engineering (LEPABE), University of Porto , Porto , Portugal.,b Institute for Biotechnology and Bioengineering (IBB), Centre of Biological Engineering, Universidade do Minho , Braga , Portugal
| | - Luís F Melo
- a Department of Chemical Engineering, Faculty of Engineering , Laboratory for Process Engineering, Environment, and Energy and Biotechnology Engineering (LEPABE), University of Porto , Porto , Portugal
| | - Nuno F Azevedo
- a Department of Chemical Engineering, Faculty of Engineering , Laboratory for Process Engineering, Environment, and Energy and Biotechnology Engineering (LEPABE), University of Porto , Porto , Portugal
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Rhl quorum sensing affects the virulence potential of Pseudomonas aeruginosa in an experimental urinary tract infection. Antonie Van Leeuwenhoek 2016; 109:1535-1544. [DOI: 10.1007/s10482-016-0755-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 08/16/2016] [Indexed: 11/26/2022]
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10
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Hutchison JB, Rodesney CA, Kaushik KS, Le HH, Hurwitz DA, Irie Y, Gordon VD. Single-cell control of initial spatial structure in biofilm development using laser trapping. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:4522-4530. [PMID: 24684606 DOI: 10.1021/la500128y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Biofilms are sessile communities of microbes that are spatially structured by an embedding matrix. Biofilm infections are notoriously intractable. This arises, in part, from changes in the bacterial phenotype that result from spatial structure. Understanding these interactions requires methods to control the spatial structure of biofilms. We present a method for growing biofilms from initiating cells whose positions are controlled with single-cell precision using laser trapping. The native growth, motility, and surface adhesion of positioned microbes are preserved, as we show for model organisms Pseudomonas aeruginosa and Staphylococcus aureus. We demonstrate that laser-trapping and placing bacteria on surfaces can reveal the effects of spatial structure on bacterial growth in early biofilm development.
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Affiliation(s)
- Jaime B Hutchison
- Center for Nonlinear Dynamics and Department of Physics and ‡School of Biological Sciences, The University of Texas at Austin , Austin, Texas 78712, United States
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Choosing an appropriate infection model to study quorum sensing inhibition in Pseudomonas infections. Int J Mol Sci 2013; 14:19309-40. [PMID: 24065108 PMCID: PMC3794835 DOI: 10.3390/ijms140919309] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 09/13/2013] [Accepted: 09/17/2013] [Indexed: 02/07/2023] Open
Abstract
Bacteria, although considered for decades to be antisocial organisms whose sole purpose is to find nutrients and multiply are, in fact, highly communicative organisms. Referred to as quorum sensing, cell-to-cell communication mechanisms have been adopted by bacteria in order to co-ordinate their gene expression. By behaving as a community rather than as individuals, bacteria can simultaneously switch on their virulence factor production and establish successful infections in eukaryotes. Understanding pathogen-host interactions requires the use of infection models. As the use of rodents is limited, for ethical considerations and the high costs associated with their use, alternative models based on invertebrates have been developed. Invertebrate models have the benefits of low handling costs, limited space requirements and rapid generation of results. This review presents examples of such models available for studying the pathogenicity of the Gram-negative bacterium Pseudomonas aeruginosa. Quorum sensing interference, known as quorum quenching, suggests a promising disease-control strategy since quorum-quenching mechanisms appear to play important roles in microbe-microbe and host-pathogen interactions. Examples of natural and synthetic quorum sensing inhibitors and their potential as antimicrobials in Pseudomonas-related infections are discussed in the second part of this review.
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Cerqueira L, Oliveira JA, Nicolau A, Azevedo NF, Vieira MJ. Biofilm formation with mixed cultures of Pseudomonas aeruginosa/Escherichia coli on silicone using artificial urine to mimic urinary catheters. BIOFOULING 2013; 29:829-40. [PMID: 23837894 DOI: 10.1080/08927014.2013.807913] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
In this study, single and dual species biofilms of Pseudomonas aeruginosa and Escherichia coli, two common bacteria associated with urinary tract infections, were formed in silicon coupons immersed in artificial urine medium. In single species experiments, E. coli appeared to form biofilms more easily than P. aeruginosa. In mixed biofilms, both species apparently benefited from the presence of the other, as the average Log total cells cm(-2) of mixed biofilms (7.29 cells cm(-2)) was higher than obtained for single cultures (6.99 cells cm(-2)). However, the use of selective media seemed to indicate that P. aeruginosa was the only microorganism to benefit in mixed biofilms (Log 7 CFU of P. aeruginosa cm(-2), compared to Log 6 CFU cm(-2) obtained in pure cultures). Peptide nucleic acid-fluorescence in situ hybridization combined with confocal laser scanning microscopy confirmed that E. coli was indeed being outnumbered by P. aeruginosa at 48 h. Whereas E. coli is the main causative agent of catheter-associated urinary tract infections, the results from this study indicate that the reason for the higher prevalence of this microorganism is not related to an enhanced ability to form biofilm and outcompete other species that may also be present, but rather to a better ability to form single-species biofilms possibly due to a more frequent access to the catheter surface.
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Affiliation(s)
- Laura Cerqueira
- Centre of Biological Engineering, IBB - Institute for Biotechnology and Bioengineering, University of Minho, Braga, Portugal
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13
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Elias S, Banin E. Multi-species biofilms: living with friendly neighbors. FEMS Microbiol Rev 2012; 36:990-1004. [PMID: 22229800 DOI: 10.1111/j.1574-6976.2012.00325.x] [Citation(s) in RCA: 446] [Impact Index Per Article: 37.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 11/14/2011] [Accepted: 01/03/2012] [Indexed: 01/23/2023] Open
Abstract
Our knowledge regarding the nature and development of microbial biofilms has grown significantly since the first report of these communities by Antonie van Leeuwenhoek in the late 1600s. Nevertheless, most biofilm studies examine mono-species cultures, whereas nearly all biofilm communities in nature comprise a variety of microorganisms. The species that constitute a mixed biofilm and the interactions between these microorganisms critically influence the development and shape of the community. In this review, we focus on interactions occurring within a multi-species biofilm and their effects on the nature of the mixed community. In general, interspecies interactions involve communication, typically via quorum sensing, and metabolic cooperation or competition. Interactions among species within a biofilm can be antagonistic, such as competition over nutrients and growth inhibition, or synergistic. The latter can result in the development of several beneficial phenotypes. These include the promotion of biofilm formation by co-aggregation, metabolic cooperation where one species utilizes a metabolite produced by a neighboring species, and increased resistance to antibiotics or host immune responses compared to the mono-species biofilms. These beneficial interactions in mixed biofilms have important environmental, industrial, and clinical implications. The latter, for example, impacts the course and treatment of biofilm-related infections, such as those manifested in the lungs of cystic fibrosis patients.
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Affiliation(s)
- Sivan Elias
- The Bacterial Biofilm Research Laboratory, The Institute for Nanotechnology and Advanced Materials, The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
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14
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Bacteria competing with the adhesion and biofilm formation by Staphylococcus aureus. Folia Microbiol (Praha) 2010; 55:497-501. [DOI: 10.1007/s12223-010-0082-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Revised: 12/15/2009] [Indexed: 10/19/2022]
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15
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Harjai K, Kumar R, Singh S. Garlic blocks quorum sensing and attenuates the virulence of Pseudomonas aeruginosa. ACTA ACUST UNITED AC 2009; 58:161-8. [PMID: 19878318 DOI: 10.1111/j.1574-695x.2009.00614.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen that colonizes urinary catheters, forms biofilms, and is responsible for causing persistent and recurrent nosocomial catheter-associated urinary tract infections (UTIs). These infections show increased morbidity and mortality in immunocompromised patients. Quorum sensing in P. aeruginosa plays a key role in biofilm formation, virulence factor production and antimicrobial resistance. Because of emerging antimicrobial resistance in P. aeruginosa, there is a need to find an alternate nonantibiotic agent for the control of infections caused by this organism. In the present study, garlic was evaluated as a prophylactic agent in vivo in a mouse UTI model. Oral treatment with garlic significantly lowered renal bacterial counts and protected mouse kidney from tissue destruction. In vitro data showed decreased elaboration of virulence factors and reduced production of quorum-sensing signals by P. aeruginosa in the presence of fresh garlic extract. The results suggest that decreased virulence of P. aeruginosa in garlic-fed mice can be attributed to the quorum-sensing inhibitory property of garlic. This might have contributed towards reduced production of virulence factors, as seen in vitro.
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Affiliation(s)
- Kusum Harjai
- Department of Microbiology, Basic Medical Sciences Block, Panjab University, Chandigarh, India.
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16
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Quorum sensing is necessary for the virulence of Pseudomonas aeruginosa during urinary tract infection. Kidney Int 2009; 76:286-92. [PMID: 19494801 DOI: 10.1038/ki.2009.183] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Quorum sensing is a signaling pathway used by bacteria to monitor their population density by detecting small diffusible molecules. To understand the role of quorum sensing in pathogenesis of urinary tract infections, wild type Pseudomonas aeruginosa, having both functional las and rhl quorum sensing systems, and its isogenic single and double mutants were used in a mouse model of ascending urinary tract infection. Mice were evaluated on the basis of bacteriological and histopathological examinations, detection of acyl homoserine lactone, and the pathologic index factors of renal and bladder tissue. Single as well as double mutant strains were able to reach renal tissue, but they were not able to multiply and cause tissue damage. Reduced rates of infection, mild histopathologic lesions, and decreased production of pathologic index factors like myeloperoxidase, malondialdehyde, and reactive nitrogen intermediates were found in these groups of mice as compared to mice infected with a standard strain (PAO1) possessing both functional sensing systems. Loss of any one of the quorum-sensing components significantly reduced the in vivo virulence of P. aeruginosa in this mouse model of ascending urinary tract infection. Our results suggests that quorum-sensing signals may act as virulence factors and are essential for P. aeruginosa multiplication and virulence during the course of urinary tract infection.
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de Goffau MC, Yang X, van Dijl JM, Harmsen HJM. Bacterial pleomorphism and competition in a relative humidity gradient. Environ Microbiol 2009; 11:809-22. [DOI: 10.1111/j.1462-2920.2008.01802.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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