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Malviya J, Alameri AA, Al-Janabi SS, Fawzi OF, Azzawi AL, Obaid RF, Alsudani AA, Alkhayyat AS, Gupta J, Mustafa YF, Karampoor S, Mirzaei R. Metabolomic profiling of bacterial biofilm: trends, challenges, and an emerging antibiofilm target. World J Microbiol Biotechnol 2023; 39:212. [PMID: 37256458 DOI: 10.1007/s11274-023-03651-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Accepted: 05/17/2023] [Indexed: 06/01/2023]
Abstract
Biofilm-related infections substantially contribute to bacterial illnesses, with estimates indicating that at least 80% of such diseases are linked to biofilms. Biofilms exhibit unique metabolic patterns that set them apart from their planktonic counterparts, resulting in significant metabolic reprogramming during biofilm formation. Differential glycolytic enzymes suggest that central metabolic processes are markedly different in biofilms and planktonic cells. The glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is highly expressed in Staphylococcus aureus biofilm progenitors, indicating that changes in glycolysis activity play a role in biofilm development. Notably, an important consideration is a correlation between elevated cyclic di-guanylate monophosphate (c-di-GMP) activity and biofilm formation in various bacteria. C-di-GMP plays a critical role in maintaining the persistence of Pseudomonas aeruginosa biofilms by regulating alginate production, a significant biofilm matrix component. Furthermore, it has been demonstrated that S. aureus biofilm development is initiated by several tricarboxylic acid (TCA) intermediates in a FnbA-dependent manner. Finally, Glucose 6-phosphatase (G6P) boosts the phosphorylation of histidine-containing protein (HPr) by increasing the activity of HPr kinase, enhancing its interaction with CcpA, and resulting in biofilm development through polysaccharide intercellular adhesion (PIA) accumulation and icaADBC transcription. Therefore, studying the metabolic changes associated with biofilm development is crucial for understanding the complex mechanisms involved in biofilm formation and identifying potential targets for intervention. Accordingly, this review aims to provide a comprehensive overview of recent advances in metabolomic profiling of biofilms, including emerging trends, prevailing challenges, and the identification of potential targets for anti-biofilm strategies.
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Affiliation(s)
- Jitendra Malviya
- Department of Life Sciences and Biological Sciences, IES University, Bhopal, India
| | - Ameer A Alameri
- Department of Chemistry, College of Science, University of Babylon, Babylon, Iraq
| | - Saif S Al-Janabi
- Medical Laboratory Techniques Department, Al-Maarif University College, Ramadi, Iraq
| | | | | | - Rasha Fadhel Obaid
- Department of Biomedical Engineering, Al-Mustaqbal University College, Babylon, Iraq
| | - Ali A Alsudani
- College of Science, University of Al-Qadisiyah, Al-Diwaniyah, Iraq
| | - Ameer S Alkhayyat
- Medical Laboratory Technology Department, College of Medical Technology, The Islamic University, Najaf, Iraq
| | - Jitendra Gupta
- Institute of Pharmaceutical Research, GLA University, Mathura, 281406, U. P., India
| | - Yasser Fakri Mustafa
- Department of Pharmaceutical Chemistry, College of Pharmacy, University of Mosul, Mosul, 41001, Iraq
| | - Sajad Karampoor
- Gastrointestinal and Liver Diseases Research Center, Iran University of Medical Sciences, Tehran, Iran.
| | - Rasoul Mirzaei
- Venom and Biotherapeutics Molecules Lab, Medical Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran.
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Biology and Regulation of Staphylococcal Biofilm. Int J Mol Sci 2023; 24:ijms24065218. [PMID: 36982293 PMCID: PMC10049468 DOI: 10.3390/ijms24065218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 02/15/2023] [Accepted: 03/03/2023] [Indexed: 03/11/2023] Open
Abstract
Despite continuing progress in medical and surgical procedures, staphylococci remain the major Gram-positive bacterial pathogens that cause a wide spectrum of diseases, especially in patients requiring the utilization of indwelling catheters and prosthetic devices implanted temporarily or for prolonged periods of time. Within the genus, if Staphylococcus aureus and S. epidermidis are prevalent species responsible for infections, several coagulase-negative species which are normal components of our microflora also constitute opportunistic pathogens that are able to infect patients. In such a clinical context, staphylococci producing biofilms show an increased resistance to antimicrobials and host immune defenses. Although the biochemical composition of the biofilm matrix has been extensively studied, the regulation of biofilm formation and the factors contributing to its stability and release are currently still being discovered. This review presents and discusses the composition and some regulation elements of biofilm development and describes its clinical importance. Finally, we summarize the numerous and various recent studies that address attempts to destroy an already-formed biofilm within the clinical context as a potential therapeutic strategy to avoid the removal of infected implant material, a critical event for patient convenience and health care costs.
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Yu L, Hisatsune J, Kutsuno S, Sugai M. New Molecular Mechanism of Superbiofilm Elaboration in a Staphylococcus aureus Clinical Strain. Microbiol Spectr 2023; 11:e0442522. [PMID: 36719203 PMCID: PMC10100805 DOI: 10.1128/spectrum.04425-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 01/05/2023] [Indexed: 02/01/2023] Open
Abstract
Previously, we reported a novel regulator of biofilm (rob) with a nonsense mutation in the superbiofilm-elaborating strain JP080. Intriguingly, the complementation of JP080 with wild-type rob did not completely abolish its superbiofilm-elaborating phenotype. Therefore, we searched for other possible mutation(s) using complete genome sequence data and found a missense mutation in the gene icaR, which altered its 35th amino acid (Ala35Thr). To further study the mechanism of superbiofilm elaboration in JP080, we reconstructed the same mutations of rob and icaR in the strain FK300 and analyzed the phenotypes. The mutation of rob (A331T) increased biofilm elaboration, as previously demonstrated; similarly, an icaR mutation increased poly-N-acetylglucosamine and biofilm production in strain FK300. Furthermore, our analyses indicated that the double mutant of rob and icaR produced significantly more biofilms than the single mutants. Additionally, gel shift analysis revealed that the icaR from JP080 lost its ability to bind to the ica promoter region. These findings suggest that the icaR mutation in JP080 may result in a nonfunctional protein. We compared ica operon expression in an icaR single mutant, rob single mutant, and rob and icaR double mutant to the wild type. The rob and icaR mutants showed increased ica operon transcription by approximately 19- and 79-fold, respectively. However, the rob and icaR double mutant showed an approximately 350-fold increase, indicating the synergistic effects of icaR and rob on JP080 biofilm elaboration. Consequently, we concluded that the double mutations rob and icaR synergistically increased ica operon transcription, resulting in a superbiofilm phenotype in Staphylococcus aureus. IMPORTANCE Poly-N-acetylglucosamine (PNAG) is a major component of S. aureus biofilm. PNAG production is mediated by the products of four genes, icaADBC encoded in the ica operon, and the major negative regulator of this operon is IcaR encoded just upstream of icaADBC. Previously, we reported another negative regulator, Rob, through gene expression analysis of clinically isolated superbiofilm-elaborating strain JP080. The rob gene is encoded at different loci distant from the ica operon. Here, we report that JP080 also carried a mutation in icaR and demonstrated that IcaR and Rob synergistically regulate PNAG production. We successfully reconstructed these mutations in a wild type, and the double mutant resulted in superbiofilm-elaborating phenotype. We clearly show that loss of function of both IcaR and Rob is the very reason that JP080 is showing the superbiofilm-elaborating phenotype. This study clearly demonstrated there are at least two independent regulators synergistically fine-tuning PNAG production and suggested the complex regulatory mechanism of biofilm production.
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Affiliation(s)
- Liansheng Yu
- Antimicrobial Resistance Research Centre, National Institute of Infectious Diseases, Tokyo, Japan
- Project Research Center for Nosocomial Infectious Diseases, Hiroshima University, Hiroshima, Japan
- Department of Antimicrobial Resistance, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Junzo Hisatsune
- Antimicrobial Resistance Research Centre, National Institute of Infectious Diseases, Tokyo, Japan
- Project Research Center for Nosocomial Infectious Diseases, Hiroshima University, Hiroshima, Japan
- Department of Antimicrobial Resistance, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Shoko Kutsuno
- Antimicrobial Resistance Research Centre, National Institute of Infectious Diseases, Tokyo, Japan
- Project Research Center for Nosocomial Infectious Diseases, Hiroshima University, Hiroshima, Japan
- Department of Antimicrobial Resistance, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Motoyuki Sugai
- Antimicrobial Resistance Research Centre, National Institute of Infectious Diseases, Tokyo, Japan
- Project Research Center for Nosocomial Infectious Diseases, Hiroshima University, Hiroshima, Japan
- Department of Antimicrobial Resistance, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
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Nunez C, Kostoulias X, Peleg A, Short F, Qu Y. A comprehensive comparison of biofilm formation and capsule production for bacterial survival on hospital surfaces. Biofilm 2023; 5:100105. [PMID: 36711324 PMCID: PMC9880390 DOI: 10.1016/j.bioflm.2023.100105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 01/16/2023] [Accepted: 01/20/2023] [Indexed: 01/23/2023] Open
Abstract
Biofilm formation and capsule production are known microbial strategies used by bacterial pathogens to survive adverse conditions in the hospital environment. The relative importance of these strategies individually is unexplored. This project aims to compare the contributory roles of biofilm formation and capsule production in bacterial survival on hospital surfaces. Representative strains of bacterial species often causing hospital-acquired infections were selected, including Acinetobacter baumannii, Klebsiella pneumoniae, Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa. The importance of biofilm formation and capsule production on bacterial survival was evaluated by comparing capsule-positive wild-type and capsule-deficient mutant strains, and biofilm and planktonic growth modes respectively, against three adverse hospital conditions, including desiccation, benzalkonium chloride disinfection and ultraviolet (UV) radiation. Bacterial survival was quantitatively assessed using colony-forming unit (CFU) enumeration and the 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay and qualitatively by scanning electron microscopy (SEM). Correlations between capsule production and biofilm formation were further investigated. Biofilm formation contributed significantly to bacterial survival on hospital surface simulators, mediating high resistance to desiccation, benzalkonium chloride disinfection and UV radiation. The role of capsule production was minor and species-specific; encapsulated A. baumannii but not K. pneumoniae cells demonstrated slightly increased resistance to desiccation, and neither showed enhanced resistance to benzalkonium chloride. Interestingly, capsule production sensitized K. pneumoniae and A. baumannii to UV radiation. The loss of capsule in K. pneumoniae and A. baumannii enhanced biofilm formation, possibly by increasing cell surface hydrophobicity. In summary, this study confirms the crucial role of biofilm formation in bacterial survival on hospital surfaces. Conversely, encapsulation plays a relatively minor role and may even negatively impact bacterial biofilm formation and hospital survival.
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Affiliation(s)
- Charles Nunez
- Infection Program, Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, Victoria, 3800, Australia
| | - Xenia Kostoulias
- Infection Program, Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, Victoria, 3800, Australia,Department of Infectious Diseases, The Alfred Hospital and Central Clinical School, Monash University, Melbourne, Victoria, 3004, Australia
| | - Anton Peleg
- Infection Program, Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, Victoria, 3800, Australia,Department of Infectious Diseases, The Alfred Hospital and Central Clinical School, Monash University, Melbourne, Victoria, 3004, Australia
| | - Francesca Short
- Infection Program, Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, Victoria, 3800, Australia,Corresponding author.,
| | - Yue Qu
- Infection Program, Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, Victoria, 3800, Australia,Department of Infectious Diseases, The Alfred Hospital and Central Clinical School, Monash University, Melbourne, Victoria, 3004, Australia,Corresponding author. Infection Program, Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, Victoria, 3800, Australia.
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Choi E, Wells B, Mirabella G, Atkins E, Choi S. Anti-biofilm activity of Pseudomonas fluorescens culture supernatants on biofilm formation of Staphylococcus epidermidis 1457. BMC Res Notes 2022; 15:370. [PMID: 36510276 PMCID: PMC9743590 DOI: 10.1186/s13104-022-06257-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 11/24/2022] [Indexed: 12/14/2022] Open
Abstract
OBJECTIVE Staphylococcus epidermidis is a skin colonizer and a major cause of nosocomial infections that can lead to sepsis. It causes opportunistic infections by forming biofilms on medical devices, which are hard to control with conventional antibiotics. In an attempt to develop its biofilm inhibitors, the culture supernatant (CS) of Pseudomonas fluorescens was assessed. This study examined the effect of the CS on S. epidermidis 1457 biofilm formation, the characteristics of inhibitors in the CS, and the differential gene expression of S. epidermidis when treated with the CS. RESULTS P. fluorescens CS specifically targeted the maturation stage of S. epidermidis biofilm formation while not affecting planktonic growth. RT-qPCR analysis revealed that P. fluorescens CS significantly downregulated S. epidermidis ica genes and upregulated an ica repressor, tcaR. This indicates that the CS reduced polysaccharide intercellular adhesin synthesis, a major component of the S. epidermidis 1457 biofilm matrix. Further studies are required to elucidate the specific inhibitory components in the CS and their mechanism of action. Our results indicate that inhibitors in the P. fluorescens CS may have a significant value for inhibiting S. epidermidis biofilm. Combinations of specific inhibitors from the CS and antibiotics against staphylococci may provide an effective measure to control S. epidermidis biofilm formation while avoiding antibiotic resistance and compensating the attenuated effectiveness of antibiotics on biofilms.
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Affiliation(s)
- Euna Choi
- grid.441145.10000 0004 0414 0983Biology Department, Union University, 1050 Union University Drive, Jackson, TN 38305 USA
| | - Bethany Wells
- grid.441145.10000 0004 0414 0983Biology Department, Union University, 1050 Union University Drive, Jackson, TN 38305 USA
| | - Gabrielle Mirabella
- grid.441145.10000 0004 0414 0983Biology Department, Union University, 1050 Union University Drive, Jackson, TN 38305 USA
| | - Emilee Atkins
- grid.441145.10000 0004 0414 0983Biology Department, Union University, 1050 Union University Drive, Jackson, TN 38305 USA
| | - Sunga Choi
- Department of Bioinformatics and Biosystems, Seongnam-Campus of Korea Polytechnics, Seongnam, South Korea
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Ahmad S, Rahman H, Qasim M, Nawab J, Alzahrani KJ, Alsharif KF, Alzahrani FM. Staphylococcus epidermidis Pathogenesis: Interplay of icaADBC Operon and MSCRAMMs in Biofilm Formation of Isolates from Pediatric Bacteremia in Peshawar, Pakistan. MEDICINA (KAUNAS, LITHUANIA) 2022; 58:1510. [PMID: 36363467 PMCID: PMC9696285 DOI: 10.3390/medicina58111510] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 10/16/2022] [Accepted: 10/20/2022] [Indexed: 11/04/2023]
Abstract
Background and Objective: Staphylococcus epidermidis is an opportunistic pathogen from pediatric bacteremia that is commonly isolated. Biofilm is the major virulence factor of S. epidermidis; however, the role of biofilm determinants in biofilm formation is highly contradictory and diverse. The current study aimed to investigate the role of polysaccharide-dependent and polysaccharide-independent pathogenic determinants in biofilm formation under physiological stress conditions. Materials and Methods: The isolates (n = 75) were identified and screened for the icaADBC operon, IS256, and an array of MSCRAMMs (Microbial Surface Component Recognizing Adhesive Matrix Molecules) through PCR analysis. The activity of the icaADBC operon was detected by Congo red assay, and the biofilm formation was analyzed through microtiter plate assay. Results: S. epidermidis isolates produced biofilm (n = 65; 86.6%) frequently. The icaA was the major representative module of the actively expressing icaADBC operon (n = 21; 80.7% sensitivity). The MSCRAMMs, including fbe (n = 59; 90.7%; p = 0.007), and embp (n = 57; 87.6%; p = 0.026), were highly prevalent and associated with biofilm positive S. epidermidis. The prevalence of icaADBC operon in biofilm positive and negative S. epidermidis was not significant (n = 41; 63%; p = 0.429). No significant association was found between IS256 and actively complete icaADBC operon (n = 10; 47.6%; p = 0.294). In the presence of 5% human plasma and glucose stress, S. epidermidis produced a strong biofilm (n = 55; 84.6%). Conclusion: The polysaccharide-dependent biofilm formation is significantly replaced (n = 21; 28%; p = 0.149) by a polysaccharide-independent mechanism (n = 59; 90.7%; p = 0.007), in which the MSCRAMMs might actively play their role. The fibrinogen-binding protein and extracellular matrix-binding protein might be potential anti-biofilm drug targets, markers of rapid diagnosis, and potential vaccine candidates of S. epidermidis involved in pediatric bacteremia.
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Affiliation(s)
- Saghir Ahmad
- Department of Microbiology, Abdul Wali Khan University, Mardan 23200, Pakistan
| | - Hazir Rahman
- Department of Microbiology, Abdul Wali Khan University, Mardan 23200, Pakistan
| | - Muhammad Qasim
- Department of Microbiology, Kohat University of Science and Technology, Kohat 26000, Pakistan
| | - Javed Nawab
- Department of Environmental Sciences, Kohat University of Science and Technology, Kohat 26000, Pakistan
| | - Khalid J. Alzahrani
- Department of Clinical Laboratories Sciences, College of Applied Medical Sciences, Taif University, Taif 21944, Saudi Arabia
| | - Khalaf F. Alsharif
- Department of Clinical Laboratories Sciences, College of Applied Medical Sciences, Taif University, Taif 21944, Saudi Arabia
| | - Fuad M. Alzahrani
- Department of Clinical Laboratories Sciences, College of Applied Medical Sciences, Taif University, Taif 21944, Saudi Arabia
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Huang K, Lin B, Liu Y, Ren H, Guo Q. Correlation Analysis between Chronic Osteomyelitis and Bacterial Biofilm. Stem Cells Int 2022; 2022:9433847. [PMID: 36117726 PMCID: PMC9477593 DOI: 10.1155/2022/9433847] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 07/29/2022] [Accepted: 08/01/2022] [Indexed: 11/20/2022] Open
Abstract
Objective To study the role of bacterial biofilm (BBF) in the formation of chronic osteomyelitis and its prevention and treatment. Methods In this paper, a large amount of relevant literature was searched for analysis and summary, and the key words "chronic osteomyelitis," "bacterial biofilm," "infection," and "debridement" were searched in databases, mainly CNKI, Wanfang, and Wipu. The search was conducted until December 2020. The role of bacterial biofilm formation in chronic osteomyelitis and its prevention were analyzed. Results Chronic osteomyelitis is formed mainly due to poor blood supply and drug-resistant bacteria, of which cellular biofilm is the most important cause. BBF forms on the surface of necrotic soft tissue and bone tissue, which has a protective effect on bacteria and greatly enhances their resistance to antibiotics, leading to difficulties in complete bacterial clearance and recurrent infections in osteomyelitis. Conclusion Through an in-depth study of the molecular biology and signal transduction of osteomyelitis biofilm, antibiotic biofilm treatment strategies and surgical debridement remain the focus of clinical translation of chronic osteomyelitis.
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Affiliation(s)
- Kai Huang
- Department of Orthopedics, Tongde Hospital of Zhejiang Province, China
| | - Bingyuan Lin
- Department of Orthopedics, Tongde Hospital of Zhejiang Province, China
| | - Yiyang Liu
- Department of Orthopedics, Tongde Hospital of Zhejiang Province, China
| | - Haiyong Ren
- Department of Orthopedics, Tongde Hospital of Zhejiang Province, China
| | - Qiaofeng Guo
- Department of Orthopedics, Tongde Hospital of Zhejiang Province, China
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Stamm J, Weißelberg S, Both A, Failla AV, Nordholt G, Büttner H, Linder S, Aepfelbacher M, Rohde H. Development of an artificial synovial fluid useful for studying Staphylococcus epidermidis joint infections. Front Cell Infect Microbiol 2022; 12:948151. [PMID: 35967857 PMCID: PMC9374174 DOI: 10.3389/fcimb.2022.948151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 07/04/2022] [Indexed: 11/24/2022] Open
Abstract
Staphylococcus epidermidis is a major causative agent of prosthetic joint infections (PJI). The ability to form biofilms supports this highly selective pathogenic potential. In vitro studies essentially relying on phenotypic assays and genetic approaches have provided a detailed picture of the molecular events contributing to biofilm assembly. A major limitation in these studies is the use of synthetic growth media, which significantly differs from the environmental conditions S. epidermidis encounters during host invasion. Building on evidence showing that growth in serum substantially affects S. epidermidis gene expression profiles and phenotypes, the major aim of this study was to develop and characterize a growth medium mimicking synovial fluid, thereby facilitating research addressing specific aspects related to PJI. Using fresh human plasma, a protocol was established allowing for the large-scale production of a medium that by biochemical analysis matches key characteristics of synovial fluid and therefore is referred to as artificial synovial fluid (ASF). By analysis of biofilm-positive, polysaccharide intercellular adhesion (PIA)-producing S. epidermidis 1457 and its isogenic, PIA- and biofilm-negative mutant 1457-M10, evidence is provided that the presence of ASF induces cluster formation in S. epidermidis 1457 and mutant 1457-M10. Consistent with the aggregative properties, both strains formed multilayered biofilms when analyzed by confocal laser scanning microscopy. In parallel to the phenotypic findings, expression analysis after growth in ASF found upregulation of genes encoding for intercellular adhesins (icaA, aap, and embp) as well as atlE, encoding for the major cell wall autolysin being responsible for eDNA release. In contrast, growth in ASF was associated with reduced expression of the master regulator agr. Collectively, these results indicate that ASF induces expression profiles that are able to support intercellular adhesion in both PIA-positive and PIA-negative S. epidermidis. Given the observation that ASF overall induced biofilm formation in a collection of S. epidermidis isolates from PJI, the results strongly support the idea of using growth media mimicking host environments. ASF may play an important role in future studies related to the pathogenesis of S. epidermidis PJI.
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Affiliation(s)
- Johanna Stamm
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
| | - Samira Weißelberg
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
| | - Anna Both
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
| | | | - Gerhard Nordholt
- Institute for Clinical Chemistry, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
| | - Henning Büttner
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
| | - Stefan Linder
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
| | - Martin Aepfelbacher
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
| | - Holger Rohde
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
- Deutsches Zentrum für Infektionsmedizin, Standort Hamburg-Lübeck-Borstel, Hamburg, Germany
- *Correspondence: Holger Rohde,
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A Combination of Pharmacophore-Based Virtual Screening, Structure-Based Lead Optimization, and DFT Study for the Identification of S. epidermidis TcaR Inhibitors. Pharmaceuticals (Basel) 2022; 15:ph15050635. [PMID: 35631461 PMCID: PMC9146354 DOI: 10.3390/ph15050635] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/05/2022] [Accepted: 05/18/2022] [Indexed: 02/01/2023] Open
Abstract
The transcriptional regulator (TcaR) enzyme plays an important role in biofilm formation. Prevention of TcaR-DNA complex formation leads to inhibit the biofilm formation is likely to reveal therapeutic ways for the treatment of bacterial infections. To identify the novel ligands for TcaR and to provide a new idea for drug design, two efficient drug design methods, such as pharmacophore modeling and structure-based drug design, were used for virtual screening of database and lead optimization, respectively. Gemifloxacin (FDA-approved drug) was considered to generate the pharmacophore model for virtual screening of the ZINC database, and five hits, namely ZINC77906236, ZINC09550296, ZINC77906466, ZINC09751390, and ZINC01269201, were identified as novel inhibitors of TcaR with better binding energies. Using structure-based drug design, a set of 7a–7p inhibitors of S. epidermidis were considered, and Mol34 was identified with good binding energy and high fitness score with improved pharmacological properties. The active site residues ARG110, ASN20, HIS42, ASN45, ALA38, VAL63, VAL68, ALA24, VAL43, ILE57, and ARG71 are playing a promising role in inhibition process. In addition, we performed DFT simulations of final hits to understand the electronic properties and their significant role in driving the inhibitor to adopt apposite bioactive conformations in the active site. Conclusively, the newly identified and designed hits from both the methods are promising inhibitors of TcaR, which can hinder biofilm formation.
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Low Concentration of the Neutrophil Proteases Cathepsin G, Cathepsin B, Proteinase-3 and Metalloproteinase-9 Induce Biofilm Formation in Non-Biofilm-Forming Staphylococcus epidermidis Isolates. Int J Mol Sci 2022; 23:ijms23094992. [PMID: 35563384 PMCID: PMC9102557 DOI: 10.3390/ijms23094992] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/26/2022] [Accepted: 04/28/2022] [Indexed: 12/04/2022] Open
Abstract
Neutrophils play a crucial role in eliminating bacteria that invade the human body; however, cathepsin G can induce biofilm formation in a non-biofilm-forming Staphylococcus epidermidis 1457 strain, suggesting that neutrophil proteases may be involved in biofilm formation. Cathepsin G, cathepsin B, proteinase-3, and metalloproteinase-9 (MMP-9) from neutrophils were tested on the biofilm induction in commensal (skin isolated) and clinical non-biofilm-forming S. epidermidis isolates. From 81 isolates, 53 (74%) were aap+, icaA−, icaD− genotype, and without the capacity of biofilm formation under conditions of 1% glucose, 4% ethanol or 4% NaCl, but these 53 non-biofilm-forming isolates induced biofilm by the use of different neutrophil proteases. Of these, 62.3% induced biofilm with proteinase-3, 15% with cathepsin G, 10% with cathepsin B and 5% with MMP -9, where most of the protease-induced biofilm isolates were commensal strains (skin). In the biofilm formation kinetics analysis, the addition of phenylmethylsulfonyl fluoride (PMSF; a proteinase-3 inhibitor) showed that proteinase-3 participates in the cell aggregation stage of biofilm formation. A biofilm induced with proteinase-3 and DNAse-treated significantly reduced biofilm formation at an early time (initial adhesion stage of biofilm formation) compared to untreated proteinase-3-induced biofilm (p < 0.05). A catheter inoculated with a commensal (skin) non-biofilm-forming S. epidermidis isolate treated with proteinase-3 and another one without the enzyme were inserted into the back of a mouse. After 7 days of incubation period, the catheters were recovered and the number of grown bacteria was quantified, finding a higher amount of adhered proteinase-3-treated bacteria in the catheter than non-proteinase-3-treated bacteria (p < 0.05). Commensal non-biofilm-forming S. epidermidis in the presence of neutrophil cells significantly induced the biofilm formation when multiplicity of infection (MOI) 1:0.01 (neutrophil:bacteria) was used, but the addition of a cocktail of protease inhibitors impeded biofilm formation. A neutrophil:bacteria assay did not induce neutrophil extracellular traps (NETs). Our results suggest that neutrophils, in the presence of commensal non-biofilm-forming S. epidermidis, do not generate NETs formation. The effect of neutrophils is the production of proteases, and proteinase-3 releases bacterial DNA at the initial adhesion, favoring cell aggregation and subsequently leading to biofilm formation.
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The Transcription Factor SpoVG Is of Major Importance for Biofilm Formation of Staphylococcus epidermidis under In Vitro Conditions, but Dispensable for In Vivo Biofilm Formation. Int J Mol Sci 2022; 23:ijms23063255. [PMID: 35328675 PMCID: PMC8949118 DOI: 10.3390/ijms23063255] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 03/14/2022] [Accepted: 03/16/2022] [Indexed: 12/13/2022] Open
Abstract
Staphylococcus epidermidis is a common cause of device related infections on which pathogens form biofilms (i.e., multilayered cell populations embedded in an extracellular matrix). Here, we report that the transcription factor SpoVG is essential for the capacity of S. epidermidis to form such biofilms on artificial surfaces under in vitro conditions. Inactivation of spoVG in the polysaccharide intercellular adhesin (PIA) producing S. epidermidis strain 1457 yielded a mutant that, unlike its parental strain, failed to produce a clear biofilm in a microtiter plate-based static biofilm assay. A decreased biofilm formation capacity was also observed when 1457 ΔspoVG cells were co-cultured with polyurethane-based peripheral venous catheter fragments under dynamic conditions, while the cis-complemented 1457 ΔspoVG::spoVG derivative formed biofilms comparable to the levels seen with the wild-type. Transcriptional studies demonstrated that the deletion of spoVG significantly altered the expression of the intercellular adhesion (ica) locus by upregulating the transcription of the ica operon repressor icaR and down-regulating the transcription of icaADBC. Electrophoretic mobility shift assays (EMSA) revealed an interaction between SpoVG and the icaA-icaR intergenic region, suggesting SpoVG to promote biofilm formation of S. epidermidis by modulating ica expression. However, when mice were challenged with the 1457 ΔspoVG mutant in a foreign body infection model, only marginal differences in biomasses produced on the infected catheter fragments between the mutant and the parental strain were observed. These findings suggest that SpoVG is critical for the PIA-dependent biofilm formation of S. epidermis under in vitro conditions, but is largely dispensable for biofilm formation of this skin commensal under in vivo conditions.
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Manandhar S, Singh A, Varma A, Pandey S, Shrivastava N. Phenotypic and genotypic characterization of biofilm producing clinical coagulase negative staphylococci from Nepal and their antibiotic susceptibility pattern. Ann Clin Microbiol Antimicrob 2021; 20:41. [PMID: 34059077 PMCID: PMC8166017 DOI: 10.1186/s12941-021-00447-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 05/24/2021] [Indexed: 11/21/2022] Open
Abstract
Background Coagulase-negative staphylococci (CNS) survive as commensals of skin, anterior nares and external canals of human and were regarded as non-infectious pathogens. However, they are emerging as a major cause of nosocomial infectious due to their ability to form biofilms and high resistance to several classes of antibiotics. This study examines the biofilm forming abilities of 214 clinical CNS isolates using phenotypic and genotypic methods, and determines their antibiotic susceptibility patterns. Methods A total of 214 clinical isolates collected from different clinical samples were identified as CNS and their antibiotic susceptibility determined by CLSI guidelines. The biofilm forming ability of all isolates was determined by three phenotypic methods; Congo red agar (CRA) method, tube adherence method (TM) and tissue culture plate (TCP) method and by genotypic method for the detection of icaAD genes. Results Among all the isolates, S. epidermidis (57.5%) was found the most frequently, followed by S. saprophyticus (18.7%), S. haemolyticus (11.2%), S. hominis (7%), and S. capitis (5.6%). Antibiotic susceptibility pattern demonstrated 91.6% isolates were resistant to penicillin and 66.8% to cefoxitin while 91.1% isolates were susceptible to chloramphenicol. Constitutive and inducible clindamycin resistant phenotype as measured by D-test was seen among 28% and 14.5% of isolates respectively. Tissue culture plate method detected biofilm production in 42.1% isolate followed by 31.8% through tube method while 20.1% isolates were found to produce slime in Congo red agar method. The genotypic assay revealed presence of icaA and icaD genes in 19.2% isolates. Conclusion The study shows a high prevalence of biofilm formation and inducible clindamycin resistance in CNS isolates, indicating the importance of in-vitro biofilm production test and D-test in routine laboratory diagnostics. Implementation of efficient diagnostic techniques for detection of biofilm production in clinical samples can help manage staphylococcal infections and minimize risks of treatment failures in hospitals.
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Affiliation(s)
- Sarita Manandhar
- Tri-Chandra Multiple College, Tribhuvan University, Kathmandu, Nepal. .,Amity Institute of Microbial Technology, Amity University Uttar Pradesh, Noida, UP, 201303, India.
| | - Anjana Singh
- Central Department of Microbiology, Tribhuvan University, Kathmandu, Nepal
| | - Ajit Varma
- Amity Institute of Microbial Technology, Amity University Uttar Pradesh, Noida, UP, 201303, India
| | - Shanti Pandey
- The University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - Neeraj Shrivastava
- Amity Institute of Microbial Technology, Amity University Uttar Pradesh, Noida, UP, 201303, India.
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13
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Vashchenko AO, Voronkova YS, Kulyk EE, Snisar OS, Sidashenko OI, Voronkova OS. Influence of sugars on biofilm formation of Staphylococcus epidermidis. REGULATORY MECHANISMS IN BIOSYSTEMS 2021. [DOI: 10.15421/022143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The problem of biofilm formation by clinical strains of opportunistic bacteria is one of the most significant for medicine, because in a state of biofilm bacteria become more resistant to environmental factors, including antibiotics, a situation that can cause failure of treatment. Among opportunistic pathogens staphylococci are of special interest. Knowledge about the peculiarities of biofilm formation of these strains, in particular the polysaccharide biosynthesis, can be used for creation of a strategy of prophylaxis of different lesions that bind with staphylococci. The effect of different concentrations of the most widespread sugars (glucose, sucrose, lactose, galactose) on the activity of biofilm formation by strains of Staphylococcus epidermidis was investigated. Strains of S. epidermidis (n = 7) were isolated from the reproductive tract of women with dysbiosis. The cultures were grown in universal synthetic media with concentration of one of the listed sugars (0.5–3.0%) during 72 h. Results were obtained colorimetrically. We studied the number of cells in biofilm and the index of biofilm formation. The largest number of cells in the biofilm was observed when the culture incubated in a medium with 2.0% of glucose (increase of 25.3 times compared to control). The amount of CFU in the control biofilm was 9.96 lg CFU/mL. The glucose concentration of 3.0% inhibited the biofilm formation: the number of cells in the biofilm was 569 times less compared to the control. The highest value of biofilm formation index was 7.2, which was 1.3 times higher than the control (5.4). In the presence of lactose and galactose in nutrient medium in concentrations from 1.0% a decrease in the number of cells and biofilm formation index were observed. The received data show that process of biofilm formation is significantly dependent on external sources of sugars, which can indicate the possibility of their use as antibiofilm drug compounds, which inhibit membrane transport of sugars in bacteria.
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14
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Nakamura K, O'Neill AM, Williams MR, Cau L, Nakatsuji T, Horswill AR, Gallo RL. Short chain fatty acids produced by Cutibacterium acnes inhibit biofilm formation by Staphylococcus epidermidis. Sci Rep 2020; 10:21237. [PMID: 33277548 PMCID: PMC7718897 DOI: 10.1038/s41598-020-77790-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 11/12/2020] [Indexed: 12/11/2022] Open
Abstract
Biofilm formation by bacterial pathogens is associated with numerous human diseases and can confer resistance to both antibiotics and host defenses. Many strains of Staphylococcus epidermidis are capable of forming biofilms and are important human pathogens. Since S. epidermidis coexists with abundant Cutibacteria acnes on healthy human skin and does not typically form a biofilm in this environment, we hypothesized that C. acnes may influence biofilm formation of S. epidermidis. Culture supernatants from C. acnes and other species of Cutibacteria inhibited S. epidermidis but did not inhibit biofilms by Pseudomonas aeruginosa or Bacillus subtilis, and inhibited biofilms by S. aureus to a lesser extent. Biofilm inhibitory activity exhibited chemical properties of short chain fatty acids known to be produced from C. acnes. The addition of the pure short chain fatty acids propionic, isobutyric or isovaleric acid to S. epidermidis inhibited biofilm formation and, similarly to C. acnes supernatant, reduced polysaccharide synthesis by S. epidermidis. Both short chain fatty acids and C. acnes culture supernatant also increased sensitivity of S. epidermidis to antibiotic killing under biofilm-forming conditions. These observations suggest the presence of C. acnes in a diverse microbial community with S. epidermidis can be beneficial to the host and demonstrates that short chain fatty acids may be useful to limit formation of a biofilm by S. epidermidis.
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Affiliation(s)
- Kouki Nakamura
- Department of Dermatology, University of California San Diego, 9500 Gillman Dr. #0869, La Jolla, CA, 92093, USA
| | - Alan M O'Neill
- Department of Dermatology, University of California San Diego, 9500 Gillman Dr. #0869, La Jolla, CA, 92093, USA
| | - Michael R Williams
- Department of Dermatology, University of California San Diego, 9500 Gillman Dr. #0869, La Jolla, CA, 92093, USA
| | - Laura Cau
- Department of Dermatology, University of California San Diego, 9500 Gillman Dr. #0869, La Jolla, CA, 92093, USA
- SILAB, R&D Department, Brive, France
| | - Teruaki Nakatsuji
- Department of Dermatology, University of California San Diego, 9500 Gillman Dr. #0869, La Jolla, CA, 92093, USA
| | - Alexander R Horswill
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, USA
| | - Richard L Gallo
- Department of Dermatology, University of California San Diego, 9500 Gillman Dr. #0869, La Jolla, CA, 92093, USA.
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15
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Effects of carbon sources and temperature on the formation and structural characteristics of food-related Staphylococcus epidermidis biofilms. FOOD SCIENCE AND HUMAN WELLNESS 2020. [DOI: 10.1016/j.fshw.2020.05.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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16
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The staphylococcal exopolysaccharide PIA - Biosynthesis and role in biofilm formation, colonization, and infection. Comput Struct Biotechnol J 2020. [PMID: 33240473 DOI: 10.1016/jcsbj202010027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Exopolysaccharide is a key part of the extracellular matrix that contributes to important mechanisms of bacterial pathogenicity, most notably biofilm formation and immune evasion. In the human pathogens Staphylococcus aureus and S. epidermidis, as well as in many other staphylococcal species, the only exopolysaccharide is polysaccharide intercellular adhesin (PIA), a cationic, partially deacetylated homopolymer of N-acetylglucosamine, whose biosynthetic machinery is encoded in the ica locus. PIA production is strongly dependent on environmental conditions and controlled by many regulatory systems. PIA contributes significantly to staphylococcal biofilm formation and immune evasion mechanisms, such as resistance to antimicrobial peptides and ingestion and killing by phagocytes, and presence of the ica genes is associated with infectivity. Due to its role in pathogenesis, PIA has raised considerable interest as a potential vaccine component or target.
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17
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Nguyen HTT, Nguyen TH, Otto M. The staphylococcal exopolysaccharide PIA - Biosynthesis and role in biofilm formation, colonization, and infection. Comput Struct Biotechnol J 2020; 18:3324-3334. [PMID: 33240473 PMCID: PMC7674160 DOI: 10.1016/j.csbj.2020.10.027] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 10/23/2020] [Accepted: 10/25/2020] [Indexed: 12/20/2022] Open
Abstract
PIA is a key extracellular matrix component in staphylococci and other bacteria. PIA is a cationic, partially deacetylated N-acetylglucosamine polymer. PIA has a major role in bacterial biofilms and biofilm-associated infection.
Exopolysaccharide is a key part of the extracellular matrix that contributes to important mechanisms of bacterial pathogenicity, most notably biofilm formation and immune evasion. In the human pathogens Staphylococcus aureus and S. epidermidis, as well as in many other staphylococcal species, the only exopolysaccharide is polysaccharide intercellular adhesin (PIA), a cationic, partially deacetylated homopolymer of N-acetylglucosamine, whose biosynthetic machinery is encoded in the ica locus. PIA production is strongly dependent on environmental conditions and controlled by many regulatory systems. PIA contributes significantly to staphylococcal biofilm formation and immune evasion mechanisms, such as resistance to antimicrobial peptides and ingestion and killing by phagocytes, and presence of the ica genes is associated with infectivity. Due to its role in pathogenesis, PIA has raised considerable interest as a potential vaccine component or target.
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Affiliation(s)
- Hoai T T Nguyen
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, 50 South Drive, Bethesda 20814, MD, USA.,School of Biotechnology, International University, Vietnam National University of Ho Chi Minh City, Khu Pho 6, Thu Duc, Ho Chi Minh City, Viet Nam
| | - Thuan H Nguyen
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, 50 South Drive, Bethesda 20814, MD, USA
| | - Michael Otto
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, U.S. National Institutes of Health, 50 South Drive, Bethesda 20814, MD, USA
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18
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Cationic conjugated polymers for enhancing beneficial bacteria adhesion and biofilm formation in gut microbiota. Colloids Surf B Biointerfaces 2020; 188:110815. [PMID: 31986332 DOI: 10.1016/j.colsurfb.2020.110815] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 12/13/2019] [Accepted: 01/19/2020] [Indexed: 11/20/2022]
Abstract
It is important to develop efficient therapeutic methods to maintain a healthy balance among gut microbiota by increasing the beneficial bacteria and decreasing the harmful bacteria. In this work, a cationic polythiophene derivative poly(3-(3'-N,N,N-triethylamino-1'-propyloxy)-4-methyl-2,5-thiophene hydrochloride) (PMNT) with quaternary ammonium groups as side chains has been used for efficiently promoting the initial adhesion and biofilm formation of beneficial bacteria in gut microbiota. Upon addition of PMNT, three species of gut microbiota have an increased biofilm formation ability (216.5 % for Escherichia coli (E. coli), 130.7 % for Bifidobacterium infantis (B. infants) and 47.6 % for Enterococcus faecalis (E. faecalis)). As the initial adhesion of bacteria to a surface is an essential step during biofilm formation, PMNT can promote the attachment of bacteria by forming bacteria /PMNT aggregates which possess more cell-to-cell interactions. RNA sequencing results of bacteria within biofilm indicate that the utilization of carbohydrate and glycan is accelerated in the presence of PMNT, leading to enhanced quorum sensing and biofilm formation of E. coli. After forming biofilm, beneficial bacteria have an enhanced resistance to adverse environmental conditions which is significant for maintaining the balance of gut microbiota. Conjugated polymers exhibit a good potential application in modulating the balance of gut microbiota and development of new probiotics drugs.
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19
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Liu J, Li W, Zhu X, Zhao H, Lu Y, Zhang C, Lu Z. Surfactin effectively inhibits Staphylococcus aureus adhesion and biofilm formation on surfaces. Appl Microbiol Biotechnol 2019; 103:4565-4574. [PMID: 31011774 DOI: 10.1007/s00253-019-09808-w] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 03/20/2019] [Accepted: 03/26/2019] [Indexed: 11/26/2022]
Abstract
Biosurfactants are amphiphilic compounds that composed of hydrophilic and hydrophobic moieties, which possess the ability of self-organizing between phases, reducing the interfacial tension, and forming aggregates such as micelles. This spontaneous process results in significant changes in surface properties that directly influence the adherence of microorganisms. In this study, the ability of surfactin, a biosurfactant produced by Bacillus subtilis in reducing adhesion and disrupting the presence of biofilm of Staphylococcus aureus (S. aureus) on several surfaces, was investigated. Significant biofilm removal was observed on glass, polystyrene, and stainless steel surfaces. Furthermore, we explored the probable mechanism about how surfactin affected S. aureus biofilm formation. Based on our findings, surfactin had a significant effect on the polysaccharides production and especially decreased the percentage of alkali-soluble polysaccharide in biofilms. It also down-regulated the expression of icaA and icaD significantly, which are necessary for the important constituents to take shape of staphylococcal biofilm. In addition, it was found that the lipopeptide affected the quorum sensing (QS) system in S. aureus through regulating the auto inducer 2 (AI-2) activity, which has been reported to be negative for biofilm formation in S. aureus. These above properties could be applied in developing surfactin as a potential pre-coating agent on material surfaces to prevent S. aureus biofilm formation.
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Affiliation(s)
- Jin Liu
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Wei Li
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xiaoyu Zhu
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Haizhen Zhao
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yingjian Lu
- Department of Nutrition and Food Science, University of Maryland, College Park, MD, 20742, USA
- College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing, 210003, China
| | - Chong Zhang
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China
| | - Zhaoxin Lu
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China.
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20
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Soumya KR, Jishma P, Sugathan S, Mathew J, Radhakrishnan EK. Biofilm Changes of Clinically Isolated Coagulase Negative Staphylococci. ACTA ACUST UNITED AC 2019. [DOI: 10.1007/s40011-019-01096-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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21
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Evaluation of Antibacterial Activity of Zataria multiflora Against the Expression of icaADB and aap Gene and Biofilm Formation in Staphylococcus epidermidis. ARCHIVES OF CLINICAL INFECTIOUS DISEASES 2019. [DOI: 10.5812/archcid.65321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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22
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Manandhar S, Singh A, Varma A, Pandey S, Shrivastava N. Biofilm Producing Clinical Staphylococcus aureus Isolates Augmented Prevalence of Antibiotic Resistant Cases in Tertiary Care Hospitals of Nepal. Front Microbiol 2018; 9:2749. [PMID: 30538678 PMCID: PMC6277500 DOI: 10.3389/fmicb.2018.02749] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 10/26/2018] [Indexed: 11/21/2022] Open
Abstract
Staphylococcus aureus, a notorious human pathogen, is a major cause of the community as well as healthcare associated infections. It can cause a diversity of recalcitrant infections mainly due to the acquisition of resistance to multiple drugs, its diverse range of virulence factors, and the ability to produce biofilm in indwelling medical devices. Such biofilm associated chronic infections often lead to increase in morbidity and mortality posing a high socio-economic burden, especially in developing countries. Since biofilm formation and antibiotic resistance function dependent on each other, detection of biofilm expression in clinical isolates would be advantageous in treatment decision. In this premise, we attempt to investigate the biofilm formation and its association with antibiotic resistance in clinical isolates from the patients visiting tertiary health care hospitals in Nepal. Bacterial cells isolated from clinical samples identified as S. aureus were examined for in-vitro biofilm production using both phenotypic and genotypic assays. The S. aureus isolates were also examined for susceptibility patterns of clinically relevant antibiotics as well as inducible clindamycin resistance using standard microbiological techniques and D-test, respectively. Among 161 S. aureus isolates, 131 (81.4%) were methicillin resistant S. aureus (MRSA) and 30 (18.6%) were methicillin sensitive S. aureus (MSSA) strains. Although a majority of MRSA strains (69.6%) showed inducible clindamycin resistance, almost all isolates (97% and 94%) were sensitive toward chloramphenicol and tetracycline, respectively. Detection of in vitro production of biofilm revealed the association of biofilm with methicillin as well as inducible clindamycin resistance among the clinical S. aureus isolates.
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Affiliation(s)
- Sarita Manandhar
- Tri-Chandra Multiple College, Tribhuvan University, Kathmandu, Nepal.,Amity Institute of Microbial Technology, Amity University, Noida, India
| | - Anjana Singh
- Central Department of Microbiology, Tribhuvan University, Kathmandu, Nepal
| | - Ajit Varma
- Amity Institute of Microbial Technology, Amity University, Noida, India
| | - Shanti Pandey
- The University of Southern Mississippi, Hattiesburg, MS, United States
| | - Neeraj Shrivastava
- Amity Institute of Microbial Technology, Amity University, Noida, India.,Institute of Biotechnology, Zhejiang University, Hangzhou, China
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Haddad O, Merghni A, Elargoubi A, Rhim H, Kadri Y, Mastouri M. Comparative study of virulence factors among methicillin resistant Staphylococcus aureus clinical isolates. BMC Infect Dis 2018; 18:560. [PMID: 30424731 PMCID: PMC6234561 DOI: 10.1186/s12879-018-3457-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 10/23/2018] [Indexed: 01/04/2023] Open
Abstract
Background Methicillin resistant Staphylococcus aureus (MRSA) is recognized worldwide as a leading cause of hospital and community infections. Biofilm formation by MRSA is an extremely important virulence factor to be understood. Our aim was to establish phenotypic and genotypic characterization of virulence factors among 43 MRSA clinical isolates in a Tunisian hospital. Methods We investigated enzymatic profiles, biofilm production and prevalences of genes encoding intracellular adhesion molecules (icaA and icaD), Microbial Surface Components Recognizing Adhesive Matrix Molecules genes (fnbA, fnbB and cna) and exoenzymes genes (geh, sspA and sspB). Results Our findings revealed that caseinase, gelatinase, lipase and lecithinase activities were detected in 100%, 100%, 76.6% and 93.3% of cases respectively. This study showed that 23 strains (76.7%) were slime producers on Congo red medium. Furthermore, 46.5% and 53.5% of isolates were respectively highly and moderately biofilm-forming on polystyrene. Significant association was found between both biofilm tests. PCR detection showed that 74.4%, 18.6%, 69.8%, 65.1% and 74.4% of isolates harbored fnbA, fnbB, icaA, icaD and cna genes respectively. In addition, 34.9%, 18.6% and 30.2% of MRSA strains were found positive for sspA, sspB and geh genes respectively. Further, statistical data showed that the presence of the fnbA and fnbB genes was significantly associated with a high biofilm production on polystyrene. However, no statistical association was observed for the icaA, icaD and cna genes. Conclusions This study indicates that the detection of fnbA and fnbB contributing to the first step of biofilm formation has been predictable of high biofilm production. As studied factors contribute to MRSA virulence, this research could be of value in orienting towards the development of new preventive and therapeutic measures.
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Affiliation(s)
- Ons Haddad
- Laboratoire de Microbiologie, CHU Fatouma Bourguiba de Monastir, Monastir, Tunisie. .,Laboratoire des Maladies Transmissible et Substances Biologiquement Actives, LR99ES27, Faculté de Pharmacie de Monastir, Université de Monastir, Monastir, Tunisie.
| | - Abderrahmen Merghni
- Laboratoire des Maladies Transmissible et Substances Biologiquement Actives, LR99ES27, Faculté de Pharmacie de Monastir, Université de Monastir, Monastir, Tunisie
| | - Aida Elargoubi
- Laboratoire de Microbiologie, CHU Fatouma Bourguiba de Monastir, Monastir, Tunisie.,Laboratoire des Maladies Transmissible et Substances Biologiquement Actives, LR99ES27, Faculté de Pharmacie de Monastir, Université de Monastir, Monastir, Tunisie
| | - Hajer Rhim
- Laboratoire de Microbiologie, CHU Fatouma Bourguiba de Monastir, Monastir, Tunisie.,Laboratoire des Maladies Transmissible et Substances Biologiquement Actives, LR99ES27, Faculté de Pharmacie de Monastir, Université de Monastir, Monastir, Tunisie
| | - Yosr Kadri
- Laboratoire de Microbiologie, CHU Fatouma Bourguiba de Monastir, Monastir, Tunisie.,Laboratoire des Maladies Transmissible et Substances Biologiquement Actives, LR99ES27, Faculté de Pharmacie de Monastir, Université de Monastir, Monastir, Tunisie
| | - Maha Mastouri
- Laboratoire de Microbiologie, CHU Fatouma Bourguiba de Monastir, Monastir, Tunisie.,Laboratoire des Maladies Transmissible et Substances Biologiquement Actives, LR99ES27, Faculté de Pharmacie de Monastir, Université de Monastir, Monastir, Tunisie
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Kot B, Sytykiewicz H, Sprawka I. Expression of the Biofilm-Associated Genes in Methicillin-Resistant Staphylococcus aureus in Biofilm and Planktonic Conditions. Int J Mol Sci 2018; 19:ijms19113487. [PMID: 30404183 PMCID: PMC6274806 DOI: 10.3390/ijms19113487] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 10/30/2018] [Accepted: 11/02/2018] [Indexed: 11/16/2022] Open
Abstract
The role of genes that are essential for development of Staphylococcus aureus biofilm during infection is not fully known. mRNA from two methicillin-resistant S. aureus strains that formed weak and strong biofilm on polystyrene plates were isolated at five time points from cells grown in biofilm and planktonic culture. Quantitative real-time PCR analysis showed that the expression levels of investigated genes under biofilm conditions were significantly higher than under planktonic conditions. The expression levels of the gene encoding elastin binding protein (ebps) and laminin binding protein (eno) were significantly increased in biofilm at 3 h, both in strongly and weakly adhering strain. The peak expression of fib gene encoding fibrinogen binding protein was found at 6 and 8 h in the case of strongly and weakly adhering strain, respectively. The expression of icaA and icaD genes in both strains was significantly higher under biofilm conditions when comparing to planktonic cells during 12 h. The expression level of the genes encoding binding proteins and the glucosamine polymer polysaccharide intercellular adhesin (PIA) slowly decreased after 24 h. Finally, we found that the expression levels of genes encoding binding factors in weakly adhering strain were significantly lower than in strongly adhering strain.
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Affiliation(s)
- Barbara Kot
- Department of Microbiology, Faculty of Natural Sciences, Siedlce University of Natural Sciences and Humanities, 14 Bolesława Prusa Str., 08-110 Siedlce, Poland.
| | - Hubert Sytykiewicz
- Department of Biochemistry and Molecular Biology, Faculty of Natural Sciences, Siedlce University of Natural Sciences and Humanities, 14 Bolesława Prusa Str., 08-110 Siedlce, Poland.
| | - Iwona Sprawka
- Department of Biochemistry and Molecular Biology, Faculty of Natural Sciences, Siedlce University of Natural Sciences and Humanities, 14 Bolesława Prusa Str., 08-110 Siedlce, Poland.
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25
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Manandhar S, Singh A, Varma A, Pandey S, Shrivastava N. Evaluation of methods to detect in vitro biofilm formation by staphylococcal clinical isolates. BMC Res Notes 2018; 11:714. [PMID: 30305150 PMCID: PMC6180658 DOI: 10.1186/s13104-018-3820-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 10/03/2018] [Indexed: 11/29/2022] Open
Abstract
Objective Staphylococcus genus comprising both Staphylococcus aureus and coagulase negative staphylococci (CoNS) are widely distributed in nature and can infect diversity of hosts. Indeed, staphylococci are the major pathogens causing biofilm associated infections caused by contaminated hospital indwelling devices. These infections are persistent in nature being highly refractory to various stresses including antibiotics. Implementation of efficient diagnostic techniques for the biofilm production would help minimize the disease burden. Thus, early detection of pathogenic strains producing biofilms warrant the utmost importance in diagnostic laboratories especially in resource limited settings. Result Among 375 isolates collected from different clinical specimens, 214 (57%) were identified as coagulase negative staphylococci and 161 (43%) S. aureus. Detection of In-vitro biofilm formation in these isolates were carried out by three commonly used phenotypic assays and a genotypic assay. While evaluating the results, tissue-culture method with supplemented glucose and sucrose showed the best correlation with the results of genotypic assay. Electronic supplementary material The online version of this article (10.1186/s13104-018-3820-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sarita Manandhar
- Tri-Chandra Multiple College, Tribhuvan University, Kathmandu, Nepal.,Amity Institute of Microbial Technology, Amity University Uttar Pradesh, Noida, UP, 201303, India
| | - Anjana Singh
- Central Department of Microbiology, Tribhuvan University, Kathmandu, Nepal
| | - Ajit Varma
- Amity Institute of Microbial Technology, Amity University Uttar Pradesh, Noida, UP, 201303, India
| | - Shanti Pandey
- The University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - Neeraj Shrivastava
- Amity Institute of Microbial Technology, Amity University Uttar Pradesh, Noida, UP, 201303, India. .,Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, People's Republic of China.
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Lee S, Kim S, Lee H, Ha J, Lee J, Choi Y, Oh H, Yoon Y, Choi KH. icaA Gene of Staphylococcus aureus Responds to NaCl, Leading to Increased Biofilm Formation. J Food Prot 2018; 81:412-416. [PMID: 29446687 DOI: 10.4315/0362-028x.jfp-17-238] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The objective of this study was to elucidate the role of the icaA gene in biofilm formation of Staphylococcus aureus exposed to NaCl. The icaA-deletion mutant of S. aureus ATCC 13565 was constructed with the temperature-sensitive plasmid pIMAY. Microtiter plate assays were performed to confirm biofilm formation for both the wild type and the mutant at 0% (control), 2, 4, and 6% NaCl. The microtiter plate assay revealed that biofilm formation by the wild type increased ( P < 0.05) as NaCl concentration increased, but biofilm formation of the mutant was not affected by NaCl concentration. Biofilm formation by the mutant was lower ( P < 0.05) than that by the wild type. These results indicate that icaA plays an important role in biofilm formation by S. aureus when the pathogen is exposed to NaCl.
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Affiliation(s)
- Soomin Lee
- 1 Department of Food and Nutrition, Sookmyung Women's University, Seoul 04310, Korea
| | - Sejeong Kim
- 1 Department of Food and Nutrition, Sookmyung Women's University, Seoul 04310, Korea
| | - Heeyoung Lee
- 1 Department of Food and Nutrition, Sookmyung Women's University, Seoul 04310, Korea
| | - Jimyeong Ha
- 1 Department of Food and Nutrition, Sookmyung Women's University, Seoul 04310, Korea
| | - Jeeyeon Lee
- 1 Department of Food and Nutrition, Sookmyung Women's University, Seoul 04310, Korea
| | - Yukyung Choi
- 1 Department of Food and Nutrition, Sookmyung Women's University, Seoul 04310, Korea
| | - Hyemin Oh
- 1 Department of Food and Nutrition, Sookmyung Women's University, Seoul 04310, Korea
| | | | - Kyoung-Hee Choi
- 2 Department of Oral Microbiology, College of Dentistry, Wonkwang University, Iksan, Jeonbuk 54896, Korea
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27
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Harraghy N, Seiler S, Jacobs K, Hannig M, Menger MD, Herrmann M. Advances in in Vitro and in Vivo Models for Studying the Staphylococcal Factors Involved in Implant Infections. Int J Artif Organs 2018; 29:368-78. [PMID: 16705605 DOI: 10.1177/039139880602900406] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Implant infections due to staphylococci are one of the greatest threats facing patients receiving implant devices. For many years researchers have sought to understand the mechanisms involved in the adherence of the bacterium to the implanted device and the formation of the unique structure, the biofilm, which protects the indwelling bacteria from the host defence and renders them resistant to antibiotic treatment. A major goal has been to develop in vitro and in vivo models that adequately reflect the real-life situation. From the simple microtiter plate assay and scanning electron microscopy, tools for studying adherence and biofilm formation have since evolved to include specialised equipment for studying adherence, flow cell systems, real-time analysis of biofilm formation using reporter gene assays both in vitro and in vivo, and a wide variety of animal models. In this article, we discuss advances in the last few years in selected in vitro and in vivo models as well as future developments in the study of adherence and biofilm formation by the staphylococci.
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Affiliation(s)
- N Harraghy
- Institute of Medical Microbiology and Hygiene, University of Saarland, Homburg/Saar, Germany.
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28
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von Eiff C, Kohnen W, Becker K, Jansen B. Modern Strategies in the Prevention of Implant-Associated Infections. Int J Artif Organs 2018; 28:1146-56. [PMID: 16353121 DOI: 10.1177/039139880502801112] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The application of medical devices either for temporary or permanent use has become an indispensible part of almost all fields of medicine. However, foreign bodies are associated with a substantial risk of bacterial and fungal infections. Implant-associated infections significantly contribute to the still increasing problem of nosocomial infections. To reduce the incidence of such infections, specific guidelines providing evidence-based recommendations and comprising both technological and nontechnological strategies for prevention have been established. Strict adherence to hygienic rules during insertion or implantation of the device are aspects of particular importance. Besides such basic and indispensable aspects, the development of new materials which could withstand microbial adherence and colonization has become a major topic in recent years. Modification of surface by primarily physico-chemical methods may lead to a change in specific and unspecific interactions with microorganisms and, thus, to a reduction in microbial adherence. Medical devices made out of a material that would be ideally antiadhesive or at least colonization-resistant would be the most suitable candidates to avoid colonization and subsequent infection. However, it appears impossible to create a surface with an absolute “zero”-adherence due to thermodynamical reasons and due to the fact that a modified material surface is in vivo rapidly covered by plasma and connective tissue proteins. Therefore, another concept for the prevention of implant-associated infections involves the impregnation of devices with various antimicrobial substances such as antibiotics, antiseptics, and/or metals. In fact, already commercially available materials for clinical use such as antimicrobial catheters have been introduced, in part with considerable impact on subsequent infections. However, future studies are warranted to translate the knowledge on the pathogenesis of device-associated infections into applicable prevention strategies.
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Affiliation(s)
- C von Eiff
- Institute of Medical Microbiology, University of Münster Hospital and Clinics, Münster, Germany.
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29
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JÄger S, Jonas B, Pfanzelt D, Horstkotte MA, Rohde H, Mack D, Knobloch JKM. Regulation of Biofilm Formation by σB is a Common Mechanism in Staphylococcus Epidermidis and is not Mediated by Transcriptional Regulation of sarA. Int J Artif Organs 2018; 32:584-91. [DOI: 10.1177/039139880903200907] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Biofilm formation is a major pathogenetic factor of Staphylococcus epidermidis. In S. epidermidis the alternative sigma factor σB was identified to regulate biofilm formation in S. epidermidis 1457. In S. aureus σB dependent regulation plays a minor role, whereas sarA (Staphylococcus accessory regulator) is an essential regulator. Therefore, we investigated the impact of σB on sarA transcription and biofilm formation in three independent S. epidermidis isolates. Mutants with dysfunctional σB displayed a strongly reduced biofilm formation, whereas in mutants with constitutive σB activity bio film formation was increased. Transcriptional analysis revealed that IcaA transcription was down-regulated in all σB negative mutants while icaR transcription was up-regulated. However, transcriptional differences varied between individual strains, indicating that additional σB-dependent regulators are involved in biofilm expression. Interestingly, despite the presence of a σB promoter beside two σA promoters no differences, or only minor ones, were observed in sarA transcription, indicating that σB-dependent sarA transcript has no influence on the phenotypic changes. The data observed in independent clinical S. epidermidis isolates suggests that, in contrast to S. aureus, regulation of biofilm formation by σB is a general feature in S. epidermidis. Additionally, we were able to demonstrate that the sarA- dependent regulation is not involved in this regulatory pathway.
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Affiliation(s)
- Sebastian JÄger
- Department of Cardiology and Pneumology, Charité Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin - Germany
| | - Beate Jonas
- Institute for Medical Microbiology and Hygiene, University of Lübeck, Lübeck - Germany
| | - Dorothea Pfanzelt
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg - Germany
| | | | - Holger Rohde
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg - Germany
| | - Dietrich Mack
- Chair of Medical Microbiology and Infectious Diseases, The School of Medicine, University of Wales Swansea, Swansea - United Kingdom
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30
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Manandhar S, Singh A, Varma A, Pandey S, Shrivastava N. Biofilm Producing Clinical Staphylococcus aureus Isolates Augmented Prevalence of Antibiotic Resistant Cases in Tertiary Care Hospitals of Nepal. Front Microbiol 2018. [PMID: 30538678 DOI: 10.3389/fmicb.2018.02749/full] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023] Open
Abstract
Staphylococcus aureus, a notorious human pathogen, is a major cause of the community as well as healthcare associated infections. It can cause a diversity of recalcitrant infections mainly due to the acquisition of resistance to multiple drugs, its diverse range of virulence factors, and the ability to produce biofilm in indwelling medical devices. Such biofilm associated chronic infections often lead to increase in morbidity and mortality posing a high socio-economic burden, especially in developing countries. Since biofilm formation and antibiotic resistance function dependent on each other, detection of biofilm expression in clinical isolates would be advantageous in treatment decision. In this premise, we attempt to investigate the biofilm formation and its association with antibiotic resistance in clinical isolates from the patients visiting tertiary health care hospitals in Nepal. Bacterial cells isolated from clinical samples identified as S. aureus were examined for in-vitro biofilm production using both phenotypic and genotypic assays. The S. aureus isolates were also examined for susceptibility patterns of clinically relevant antibiotics as well as inducible clindamycin resistance using standard microbiological techniques and D-test, respectively. Among 161 S. aureus isolates, 131 (81.4%) were methicillin resistant S. aureus (MRSA) and 30 (18.6%) were methicillin sensitive S. aureus (MSSA) strains. Although a majority of MRSA strains (69.6%) showed inducible clindamycin resistance, almost all isolates (97% and 94%) were sensitive toward chloramphenicol and tetracycline, respectively. Detection of in vitro production of biofilm revealed the association of biofilm with methicillin as well as inducible clindamycin resistance among the clinical S. aureus isolates.
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Affiliation(s)
- Sarita Manandhar
- Tri-Chandra Multiple College, Tribhuvan University, Kathmandu, Nepal
- Amity Institute of Microbial Technology, Amity University, Noida, India
| | - Anjana Singh
- Central Department of Microbiology, Tribhuvan University, Kathmandu, Nepal
| | - Ajit Varma
- Amity Institute of Microbial Technology, Amity University, Noida, India
| | - Shanti Pandey
- The University of Southern Mississippi, Hattiesburg, MS, United States
| | - Neeraj Shrivastava
- Amity Institute of Microbial Technology, Amity University, Noida, India
- Institute of Biotechnology, Zhejiang University, Hangzhou, China
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31
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Fernández M, Morales GM, Agostini E, González PS. An approach to study ultrastructural changes and adaptive strategies displayed by Acinetobacter guillouiae SFC 500-1A under simultaneous Cr(VI) and phenol treatment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:20390-20400. [PMID: 28707241 DOI: 10.1007/s11356-017-9682-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 06/29/2017] [Indexed: 06/07/2023]
Abstract
Acinetobacter guillouiae SFC 500-1A, a native bacterial strain isolated from tannery sediments, is able to simultaneously remove high concentrations of Cr(VI) and phenol. In this complementary study, high-resolution microscopy techniques, such as atomic force microscopy (AFM) and transmission electron microscopy (TEM), were used to improve our understanding of some bacterial adaptive mechanisms that enhance their ability to survive. AFM contributed in gaining insight into changes in bacterial size and morphology. It allowed the unambiguous identification of pollutant-induced cellular disturbances and the visualization of bacterial cells with depth sensitivity. TEM analysis revealed that Cr(VI) produced changes mainly at the intracellular level, whereas phenol produced alterations at the membrane level. This strain tended to form more extensive biofilms after phenol treatment, which was consistent with microscopy images and the production of exopolysaccharides (EPSs). In addition, other exopolymeric substances (DNA, proteins) significantly increased under Cr(VI) and phenol treatment. These exopolymers are important for biofilm formation playing a key role in bacterial aggregate stability, being especially useful for bioremediation of environmental pollutants. This study yields the first direct evidences of a range of different changes in A. guillouiae SFC 500-1A which seems to be adaptive strategies to survive in stressful conditions.
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Affiliation(s)
- Marilina Fernández
- Departamento de Biología Molecular, FCEFQyN, Universidad Nacional de Río Cuarto (UNRC), Ruta 36 Km 601, 5800, Río Cuarto, Córdoba, Argentina
| | - Gustavo M Morales
- Departamento de Química-FCEFQyN, Universidad Nacional de Río Cuarto, 5800, Río Cuarto, Córdoba, Argentina
| | - Elizabeth Agostini
- Departamento de Biología Molecular, FCEFQyN, Universidad Nacional de Río Cuarto (UNRC), Ruta 36 Km 601, 5800, Río Cuarto, Córdoba, Argentina
| | - Paola S González
- Departamento de Biología Molecular, FCEFQyN, Universidad Nacional de Río Cuarto (UNRC), Ruta 36 Km 601, 5800, Río Cuarto, Córdoba, Argentina.
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32
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Jardak M, Abdelli F, Laadhar R, Lami R, Stien D, Aifa S, Mnif S. Evaluation of biofilm-forming ability of bacterial strains isolated from the roof of an old house. J GEN APPL MICROBIOL 2017; 63:186-194. [PMID: 28502956 DOI: 10.2323/jgam.2016.10.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The bacterial diversity associated with biofilm-forming ability was studied. Eighteen bacterial strains were isolated from a microbial film collected from the roof of an old house located in Sfax, Tunisia. The purity of these microorganisms was confirmed by microscopic observation after repeated streaking on a Tryptic Soy agar medium. Biofilm formation was estimated using preliminary tests including a motility test, microbial adhesion to solvents (MATS), and the Congo Red Agar method (CRA). Since these tests showed no significant result, microplate tests, such as crystal violet and resazurin assays, were used. The results obtained showed that strain S61 was able to form a biofilm within 24 h (OD570 = 4.87). The viability of the S61 biofilm with resazurin assessed with fluorescence measurement was about 1.5 × 103. The S61 strain was identified as Staphylococcus epidermidis. In the biofilm studied here, it was the most biofilm-forming bacterium and will be used as a bacterial model for studying anti-biofilm activity.
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Affiliation(s)
- Marwa Jardak
- Laboratory of Molecular and Cellular Screening Processes, Centre of Biotechnology of Sfax.,Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes (LBBM), Observatoire Océanologique
| | - Faten Abdelli
- Laboratory of Molecular and Cellular Screening Processes, Centre of Biotechnology of Sfax
| | - Rahma Laadhar
- Laboratory of Molecular and Cellular Screening Processes, Centre of Biotechnology of Sfax
| | - Raphael Lami
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes (LBBM), Observatoire Océanologique
| | - Didier Stien
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes (LBBM), Observatoire Océanologique
| | - Sami Aifa
- Laboratory of Molecular and Cellular Screening Processes, Centre of Biotechnology of Sfax
| | - Sami Mnif
- Laboratory of Molecular and Cellular Screening Processes, Centre of Biotechnology of Sfax
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33
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Ma R, Qiu S, Jiang Q, Sun H, Xue T, Cai G, Sun B. AI-2 quorum sensing negatively regulates rbf expression and biofilm formation in Staphylococcus aureus. Int J Med Microbiol 2017; 307:257-267. [PMID: 28416278 DOI: 10.1016/j.ijmm.2017.03.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Indexed: 12/11/2022] Open
Abstract
Staphylococcus aureus is an important pathogen that is capable of forming biofilms on biomaterial surfaces to cause biofilm-associated infections. Autoinducer 2 (AI-2), a universal language for interspecies communication, is involved in a variety of physiological activities, although its exact role in Gram-positive bacteria, especially in S. aureus, is not yet thoroughly characterized. Herein we demonstrate that inactivation of luxS, which encodes AI-2 synthase, resulted in increased biofilm formation and higher polysaccharide intercellular adhesion (PIA) production compared with the wild-type strain in S. aureus NCTC8325. The transcript level of rbf, a positive regulator of biofilm formation, was significantly increased in the luxS mutant. All of the parental phenotypes could be restored by genetic complementation and chemically synthesized 4,5-dihydroxy-2,3-pentanedione, the AI-2 precursor molecule, suggesting that AI-2 has a signaling function to regulate rbf transcription and biofilm formation in S. aureus. Phenotypic analysis revealed that the luxS rbf double mutant produced approximately the same amount of biofilms and PIA as the rbf mutant. In addition, real-time quantitative reverse transcription-PCR analysis showed that the icaA transcript level of the rbf mutant was similar to that of the luxS rbf double mutant. These findings demonstrate that the LuxS/AI-2 system regulates PIA-dependent biofilm formation via repression of rbf expression in S. aureus. Furthermore, we demonstrated that Rbf could bind to the sarX and rbf promoters to upregulate their expression.
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Affiliation(s)
- Ronghua Ma
- CAS Key Laboratory of Innate Immunity and Chronic Disease, University of Science and Technology of China, Hefei, Anhui 230027, China; School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Shuwan Qiu
- School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Qiu Jiang
- CAS Key Laboratory of Innate Immunity and Chronic Disease, University of Science and Technology of China, Hefei, Anhui 230027, China; School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Haipeng Sun
- CAS Key Laboratory of Innate Immunity and Chronic Disease, University of Science and Technology of China, Hefei, Anhui 230027, China; School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Ting Xue
- School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Gang Cai
- School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui 230027, China; Hefei National Laboratory for Physical Sciences at Microscale, Hefei, Anhui 230027, China.
| | - Baolin Sun
- CAS Key Laboratory of Innate Immunity and Chronic Disease, University of Science and Technology of China, Hefei, Anhui 230027, China; School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui 230027, China; Hefei National Laboratory for Physical Sciences at Microscale, Hefei, Anhui 230027, China.
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A Novel Repressor of the ica Locus Discovered in Clinically Isolated Super-Biofilm-Elaborating Staphylococcus aureus. mBio 2017; 8:mBio.02282-16. [PMID: 28143981 PMCID: PMC5285506 DOI: 10.1128/mbio.02282-16] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Staphylococcus aureus TF2758 is a clinical isolate from an atheroma and a super-biofilm-elaborating/polysaccharide intercellular adhesin (PIA)/poly-N-acetylglucosamine (PNAG)-overproducing strain (L. Shrestha et al., Microbiol Immunol 60:148–159, 2016, https://doi.org/10.1111/1348-0421.12359). A microarray analysis and DNA genome sequencing were performed to identify the mechanism underlying biofilm overproduction by TF2758. We found high transcriptional expression levels of a 7-gene cluster (satf2580 to satf2586) and the ica operon in TF2758. Within the 7-gene cluster, a putative transcriptional regulator gene designated rob had a nonsense mutation that caused the truncation of the protein. The complementation of TF2758 with rob from FK300, an rsbU-repaired derivative of S. aureus strain NCTC8325-4, significantly decreased biofilm elaboration, suggesting a role for rob in this process. The deletion of rob in non-biofilm-producing FK300 significantly increased biofilm elaboration and PIA/PNAG production. In the search for a gene(s) in the 7-gene cluster for biofilm elaboration controlled by rob, we identified open reading frame (ORF) SAOUHSC_2898 (satf2584). Our results suggest that ORF SAOUHSC_2898 (satf2584) and icaADBC are required for enhanced biofilm elaboration and PIA/PNAG production in the rob deletion mutant. Rob bound to a palindromic sequence within its own promoter region. Furthermore, Rob recognized the TATTT motif within the icaR-icaA intergenic region and bound to a 25-bp DNA stretch containing this motif, which is a critically important short sequence regulating biofilm elaboration in S. aureus. Our results strongly suggest that Rob is a long-sought repressor that recognizes and binds to the TATTT motif and is an important regulator of biofilm elaboration through its control of SAOUHSC_2898 (SATF2584) and Ica protein expression in S. aureus. During the search for molecular mechanisms underlying biofilm overproduction of Staphylococcus aureus TF2758, we found a putative transcriptional regulator gene designated rob within a 7-gene cluster showing a high transcriptional expression level by microarray analysis. The deletion of rob in non-biofilm-producing FK300, an rsbU-repaired derivative of NCTC8325-4, significantly increased biofilm elaboration and PIA/PNAG production. The search for a gene(s) in the 7-gene cluster for biofilm elaboration controlled by rob identified ORF SAOUHSC_2898. Besides binding to its own promoter region to control ORF SAOUHSC_2898 expression, Rob recognized the TATTT motif within the icaR-icaA intergenic region and bound to a 25-bp DNA stretch containing this motif, which is a critically important short sequence regulating biofilm elaboration in S. aureus. Our results strongly suggest that Rob is a long-sought repressor that recognizes and binds to the TATTT motif and is a new important regulator of biofilm elaboration through its control of SAOUHSC_2898 and Ica protein expression in S. aureus.
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35
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Overview of Genetic Background Beyond Polysaccharide Intercellular Adhesion Production in Staphylococcus epidermidis. Jundishapur J Microbiol 2016. [DOI: 10.5812/jjm.36008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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36
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Pinheiro L, Brito CI, Oliveira AD, Pereira VC, Cunha MDLRDSD. Staphylococcus epidermidis and Staphylococcus haemolyticus: detection of biofilm genes and biofilm formation in blood culture isolates from patients in a Brazilian teaching hospital. Diagn Microbiol Infect Dis 2016; 86:11-4. [PMID: 27344542 DOI: 10.1016/j.diagmicrobio.2016.06.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 05/17/2016] [Accepted: 06/04/2016] [Indexed: 11/27/2022]
Abstract
Infections with coagulase-negative staphylococci are often related to biofilm formation. This study aimed to detect biofilm formation and biofilm-associated genes in blood culture isolates of Staphylococcus epidermidis and S. haemolyticus. Half (50.6%) of the 85 S. epidermidis isolates carried the icaAD genes and 15.3% the bhp gene, while these numbers were 42.9% and 0 for S. haemolyticus, respectively. According to the plate test, 30 S. epidermidis isolates were biofilm producers and 40% of them were strongly adherent, while only one (6%) of the 17 S. haemolyticus biofilm-producing isolates exhibited a strongly adherent biofilm. The concomitant presence of icaA and icaD was significantly associated with the plate and tube test results (P ≤ 0.0004). The higher frequency of icaA in S. epidermidis and of icaD in S. haemolyticus is correlated with the higher biofilm-producing capacity of the former since, in contrast to IcaD, IcaA activity is sufficient to produce small amounts of polysaccharide. Although this study emphasizes the importance of icaAD and bhp for biofilm formation in S. epidermidis, other mechanisms seem to be involved in S. haemolyticus.
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Affiliation(s)
- Luiza Pinheiro
- Departamento de Microbiologia e Imunologia, Instituto de Biociências, Universidade Estadual Paulista, UNESP, Botucatu, SP, Brazil; Laboratório de Patologia,Instituto Lauro de Souza Lima, Bauru, SP, Brazil.
| | - Carla Ivo Brito
- Departamento de Microbiologia e Imunologia, Instituto de Biociências, Universidade Estadual Paulista, UNESP, Botucatu, SP, Brazil
| | - Adilson de Oliveira
- Departamento de Microbiologia e Imunologia, Instituto de Biociências, Universidade Estadual Paulista, UNESP, Botucatu, SP, Brazil.
| | - Valéria Cataneli Pereira
- Departamento de Microbiologia e Imunologia, Instituto de Biociências, Universidade Estadual Paulista, UNESP, Botucatu, SP, Brazil.
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37
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Van Kerckhoven M, Hotterbeekx A, Lanckacker E, Moons P, Lammens C, Kerstens M, Ieven M, Delputte P, Jorens PG, Malhotra-Kumar S, Goossens H, Maes L, Cos P. Characterizing the in vitro biofilm phenotype of Staphylococcus epidermidis isolates from central venous catheters. J Microbiol Methods 2016; 127:95-101. [PMID: 27196636 DOI: 10.1016/j.mimet.2016.05.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 05/14/2016] [Accepted: 05/14/2016] [Indexed: 01/03/2023]
Abstract
Central venous catheter (CVC)-related infections are commonly caused by Staphylococcus epidermidis that is able to form a biofilm on the catheter surface. Many studies involving biofilm formation by Staphylococcus have been published each adopting an own in vitro model. Since the capacity to form a biofilm depends on multiple environmental factors, direct comparison of results obtained in different studies remains challenging. This study characterized the phenotype (strong versus weak biofilm-producers) of S. epidermidis from CVCs in four different in vitro biofilm models, covering differences in material type (glass versus polymer) and nutrient presentation (static versus continuous flow). A good correlation in phenotype was obtained between glass and polymeric surfaces independent of nutrient flow, with 85% correspondence under static growth conditions and 80% under dynamic conditions. A 80% correspondence between static and dynamic conditions on polymeric surfaces could be demonstrated as well. Incubation time had a significant influence on the biofilm phenotype with only 55% correspondence between the dynamic models at different incubation times (48h versus 17h). Screening for the presence of biofilm-related genes only revealed that ica A was correlated with biofilm formation under static but not under dynamic conditions. In conclusion, this study highlights that a high level of standardization is necessary to interpret and compare results of different in vitro biofilm models.
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Affiliation(s)
- Marian Van Kerckhoven
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - An Hotterbeekx
- Laboratory of Medical Microbiology (LMM), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Ellen Lanckacker
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Pieter Moons
- Laboratory of Medical Microbiology (LMM), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Christine Lammens
- Laboratory of Medical Microbiology (LMM), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Monique Kerstens
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Margareta Ieven
- Laboratory of Medical Microbiology (LMM), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Peter Delputte
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Philippe G Jorens
- Intensive Care Unit, Antwerp University Hospital, University of Antwerp, Wilrijkstraat 10, 2650 Edegem, Belgium
| | - Surbhi Malhotra-Kumar
- Laboratory of Medical Microbiology (LMM), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Herman Goossens
- Laboratory of Medical Microbiology (LMM), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Louis Maes
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Paul Cos
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium.
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Budd KE, Mitchell J, Keane OM. Lineage associated expression of virulence traits in bovine-adapted Staphylococcus aureus. Vet Microbiol 2016; 189:24-31. [PMID: 27259823 DOI: 10.1016/j.vetmic.2016.04.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 03/24/2016] [Accepted: 04/18/2016] [Indexed: 10/21/2022]
Abstract
Bovine mastitis is the most costly disease to the dairy industry worldwide with Staphylococcus aureus commonly associated with intramammary infections that are persistent and refractory to treatment. The strains of S. aureus that cause mastitis predominantly belong to a number of well-described bovine-adapted lineages. The objective of this study was to determine if a variety of potential virulence traits were associated with lineage. Bovine-adapted S. aureus isolates (n=120), belonging to lineages CC97, CC151 and ST136, were tested for their ability to adhere to and internalise within cultured bovine mammary epithelial cells (bMEC), to bind bovine fibronectin, to form a biofilm in TSB, TSB+1% glucose and TSB+4% NaCl, and to induce an immune response from bMEC. There were no significant differences between the lineages in ability to adhere to or internalise within bMEC although there were significant differences between individual isolates. For lineages CC97 and ST136, mammalian cell adherence was correlated with the ability to bind bovine fibronectin, however isolates from CC151 could not bind bovine fibronectin in vitro, but adhered to bMEC in a fibronectin-independent manner. There were significant differences between the lineages in ability to form a biofilm in all three growth media with ST136 forming the strongest biofilm while CC151 formed the weakest biofilm. Lineages also differed in their ability to elicit an immune response from bMEC with CC97 eliciting a stronger immune response than CC151 and ST136. These data indicate the potential for both lineage and strain-specific virulence and a strain-specific response to infection in vivo and caution against extrapolating an effect from a single strain of S. aureus to draw conclusions regarding virulence or the host response to infection in unrelated lineages.
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Affiliation(s)
- Kathleen E Budd
- Animal & Bioscience Department, AGRIC, Teagasc, Grange, Dunsany, Co. Meath, Ireland; School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland
| | - Jennifer Mitchell
- School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland
| | - Orla M Keane
- Animal & Bioscience Department, AGRIC, Teagasc, Grange, Dunsany, Co. Meath, Ireland.
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The degree of virulence does not necessarily affect MRSA biofilm strength and response to photodynamic therapy. Microb Pathog 2016; 91:54-60. [DOI: 10.1016/j.micpath.2015.11.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 11/05/2015] [Accepted: 11/09/2015] [Indexed: 12/25/2022]
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40
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Vimberg V, Kuzma M, Stodůlková E, Novák P, Bednárová L, Šulc M, Gažák R. Hydnocarpin-Type Flavonolignans: Semisynthesis and Inhibitory Effects on Staphylococcus aureus Biofilm Formation. JOURNAL OF NATURAL PRODUCTS 2015; 78:2095-103. [PMID: 26273725 DOI: 10.1021/acs.jnatprod.5b00430] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A new, efficient, and general semisynthesis of hydnocarpin-type flavonolignans was developed and optimized, enabling gram-scale production of hydnocarpin D (2). Moreover, the syntheses of optically pure hydnocarpin isomers [(10R,11R)-hydnocarpin (1a), (10R,11R)-hydnocarpin D (2a), and (10S,11S)-hydnocarpin D (2b)], as well as the synthesis of isohydnocarpin (8), were achieved for the first time utilizing this new method. The synthesis is based on the two-step transformation of the readily available flavonolignans from milk thistle (Silybum marianum), accessible by isolation from the commercial extract silymarin. The first step relies on the regioselective formylation of the C-3 hydroxy group of the dihydroflavonol-type precursor using the Vilsmeier-Haack reagent, followed by formic acid elimination by triethylamine in the second step. The synthesized compounds were effective inhibitors of Staphylococcus aureus biofilm formation, with (10S,11S)-hydnocarpin D (2b) being the most potent inhibitor. Furthermore, the effect of glucose on biofilm formation was tested, and glucose decreased the biofilm inhibitory activity of 2b. Moreover, 2b increased the susceptibility of Staph. aureus to enrofloxacin.
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Affiliation(s)
- Vladimir Vimberg
- Institute of Microbiology of the Academy of Sciences of the Czech Republic , v.v.i., Vídeňská 1083, Prague 4, CZ 142 20, Czech Republic
| | - Marek Kuzma
- Institute of Microbiology of the Academy of Sciences of the Czech Republic , v.v.i., Vídeňská 1083, Prague 4, CZ 142 20, Czech Republic
| | - Eva Stodůlková
- Institute of Microbiology of the Academy of Sciences of the Czech Republic , v.v.i., Vídeňská 1083, Prague 4, CZ 142 20, Czech Republic
| | - Petr Novák
- Institute of Microbiology of the Academy of Sciences of the Czech Republic , v.v.i., Vídeňská 1083, Prague 4, CZ 142 20, Czech Republic
- Department of Biochemistry, Faculty of Science, Charles University in Prague , Hlavova 8, Prague 2, CZ 128 40, Czech Republic
| | - Lucie Bednárová
- Institute of Organic Chemistry and Biochemistry of the AS CR , v.v.i., Flemingovo náměstí 2, Prague 6, CZ 166 10, Czech Republic
| | - Miroslav Šulc
- Institute of Microbiology of the Academy of Sciences of the Czech Republic , v.v.i., Vídeňská 1083, Prague 4, CZ 142 20, Czech Republic
- Department of Biochemistry, Faculty of Science, Charles University in Prague , Hlavova 8, Prague 2, CZ 128 40, Czech Republic
| | - Radek Gažák
- Institute of Microbiology of the Academy of Sciences of the Czech Republic , v.v.i., Vídeňská 1083, Prague 4, CZ 142 20, Czech Republic
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Tseng SP, Lin YT, Tsai JC, Hung WC, Chen HJ, Chen PF, Hsueh PR, Teng LJ. Genotypes and phenotypes of Staphylococcus lugdunensis isolates recovered from bacteremia. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2015; 48:397-405. [DOI: 10.1016/j.jmii.2013.11.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 11/12/2013] [Accepted: 11/12/2013] [Indexed: 11/25/2022]
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42
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Cui B, Smooker PM, Rouch DA, Deighton MA. Effects of erythromycin on the phenotypic and genotypic biofilm expression in two clinical Staphylococcus capitis subspecies and a functional analysis of Ica proteins in S. capitis. J Med Microbiol 2015; 64:591-604. [DOI: 10.1099/jmm.0.000059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Bintao Cui
- School of Applied Sciences, RMIT University, Plenty Road, Bundoora, 3083 Victoria, Australia
| | - Peter M. Smooker
- School of Applied Sciences, RMIT University, Plenty Road, Bundoora, 3083 Victoria, Australia
| | - Duncan A. Rouch
- School of Applied Sciences, RMIT University, Plenty Road, Bundoora, 3083 Victoria, Australia
| | - Margaret A. Deighton
- School of Applied Sciences, RMIT University, Plenty Road, Bundoora, 3083 Victoria, Australia
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Decker R, Burdelski C, Zobiak M, Büttner H, Franke G, Christner M, Saß K, Zobiak B, Henke HA, Horswill AR, Bischoff M, Bur S, Hartmann T, Schaeffer CR, Fey PD, Rohde H. An 18 kDa scaffold protein is critical for Staphylococcus epidermidis biofilm formation. PLoS Pathog 2015; 11:e1004735. [PMID: 25799153 PMCID: PMC4370877 DOI: 10.1371/journal.ppat.1004735] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 02/06/2015] [Indexed: 12/15/2022] Open
Abstract
Virulence of the nosocomial pathogen Staphylococcus epidermidis is crucially linked to formation of adherent biofilms on artificial surfaces. Biofilm assembly is significantly fostered by production of a bacteria derived extracellular matrix. However, the matrix composition, spatial organization, and relevance of specific molecular interactions for integration of bacterial cells into the multilayered biofilm community are not fully understood. Here we report on the function of novel 18 kDa Small basic protein (Sbp) that was isolated from S. epidermidis biofilm matrix preparations by an affinity chromatographic approach. Sbp accumulates within the biofilm matrix, being preferentially deposited at the biofilm–substratum interface. Analysis of Sbp-negative S. epidermidis mutants demonstrated the importance of Sbp for sustained colonization of abiotic surfaces, but also epithelial cells. In addition, Sbp promotes assembly of S. epidermidis cell aggregates and establishment of multilayered biofilms by influencing polysaccharide intercellular-adhesin (PIA) and accumulation associated protein (Aap) mediated intercellular aggregation. While inactivation of Sbp indirectly resulted in reduced PIA-synthesis and biofilm formation, Sbp serves as an essential ligand during Aap domain-B mediated biofilm accumulation. Our data support the conclusion that Sbp serves as an S. epidermidis biofilm scaffold protein that significantly contributes to key steps of surface colonization. Sbp-negative S. epidermidis mutants showed no attenuated virulence in a mouse catheter infection model. Nevertheless, the high prevalence of sbp in commensal and invasive S. epidermidis populations suggests that Sbp plays a significant role as a co-factor during both multi-factorial commensal colonization and infection of artificial surfaces. Biofilm formation is a key phenotype allowing the otherwise harmless skin commensal S. epidermidis to establish chronic implant-associated infections, affecting millions of patients worldwide. S. epidermidis biofilm assembly relies on the production of an extracellular matrix that serves as glue to stabilize the multilayered bacterial architecture. Here we identified novel 18 kDa Small basic protein (Sbp) as a key component of the extracellular matrix that promotes pivotal steps of bacterial biofilm formation in vitro. Importantly, Sbp is deposited specifically at the interface between biofilm and substrate, as well as in larger humps interspersed within the bacterial cell architecture, thereby forming a proteinaceous biofilm scaffold. This localization enables Sbp to foster stable S. epidermidis interactions with an artificial surface and also contributes to S. epidermidis cell aggregation mechanisms, i.e., polysaccharide intercellular adhesin (PIA) and accumulation associated protein (Aap). In fact, by demonstrating direct Sbp-Aap interactions we provide the first evidence supporting the idea that specific molecular interactions between S. epidermidis and matrix components are involved in S. epidermidis biofilm accumulation. In conclusion, we here show that Sbp promotes key phenotypic features important for S. epidermidis to evolve as an opportunistic pathogen.
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Affiliation(s)
- Rahel Decker
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
| | - Christoph Burdelski
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
| | - Melanie Zobiak
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
| | - Henning Büttner
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
| | - Gefion Franke
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
| | - Martin Christner
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
| | - Katharina Saß
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
| | - Bernd Zobiak
- UKE Microscopy Imaging Facility, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
| | - Hanae A. Henke
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
| | - Alexander R. Horswill
- Department of Microbiology, Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Markus Bischoff
- Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum des Saarlandes, Homburg, Germany
| | - Stephanie Bur
- Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum des Saarlandes, Homburg, Germany
| | - Torsten Hartmann
- Institut für Medizinische Mikrobiologie und Hygiene, Universitätsklinikum des Saarlandes, Homburg, Germany
| | - Carolyn R. Schaeffer
- Department of Pathology and Microbiology, Center for Staphylococcal Research, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Paul D. Fey
- Department of Pathology and Microbiology, Center for Staphylococcal Research, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Holger Rohde
- Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Hamburg, Germany
- * E-mail:
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Xue T, Ni J, Shang F, Chen X, Zhang M. Autoinducer-2 increases biofilm formation via an ica- and bhp-dependent manner in Staphylococcus epidermidis RP62A. Microbes Infect 2015; 17:345-52. [PMID: 25637952 DOI: 10.1016/j.micinf.2015.01.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 01/14/2015] [Accepted: 01/14/2015] [Indexed: 10/24/2022]
Abstract
Staphylococcus epidermidis has become the most common cause of nosocomial bacteraemia and the principal organism responsible for indwelling medical device -associated infections. Its pathogenicity is mainly due to its ability to form biofilms on the implanted medical devices. Biofilm formation is a quorum-sensing (QS)-dependent process controlled by autoinducers, which are signalling molecules. Here, we investigated the function of the autoinducer-2 (AI-2) QS system, especially the influence of AI-2 on biofilm formation in S. epidermidis RP62A. Results showed that the addition of AI-2 leads to a significant increase in biofilm formation, in contrast with previous studies which showed that AI-2 limits biofilm formation in Staphylococci. We found that AI-2 increases biofilm formation by enhancing the transcription of the ica operon, which is a known component in the AI-2-regulated biofilm pathway. In addition, we first observed that the transcript level of bhp, which encodes a biofilm-associated protein, was also increased following the addition of AI-2. Furthermore, we found that, among the known biofilm regulator genes (icaR, sigB, rbsU, sarA, sarX, sarZ, clpP, agrA, abfR, arlRS, saeRS), only icaR can be regulated by AI-2, suggesting that AI-2 may regulate biofilm formation by an icaR-dependent mechanism in S. epidermidis RP62A.
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Affiliation(s)
- Ting Xue
- School of Life Sciences, Anhui Agricultural University, Hefei, Anhui 230036, China.
| | - Jingtian Ni
- School of Life Sciences, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Fei Shang
- School of Life Sciences, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Xiaolin Chen
- School of Life Sciences, Anhui Agricultural University, Hefei, Anhui 230036, China
| | - Ming Zhang
- School of Life Sciences, Anhui Agricultural University, Hefei, Anhui 230036, China
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45
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Carvalhais V, França A, Pier GB, Vilanova M, Cerca N, Vitorino R. Comparative proteomic and transcriptomic profile of Staphylococcus epidermidis biofilms grown in glucose-enriched medium. Talanta 2014; 132:705-12. [PMID: 25476368 DOI: 10.1016/j.talanta.2014.10.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Revised: 10/01/2014] [Accepted: 10/08/2014] [Indexed: 01/07/2023]
Abstract
Staphylococcus epidermidis is an important nosocomial agent among carriers of indwelling medical devices, due to its strong ability to form biofilms on inert surfaces. Contrary to some advances made in the transcriptomic field, proteome characterization of S. epidermidis biofilms is less developed. To highlight the relation between transcripts and proteins of S. epidermidis biofilms, we analyzed the proteomic profile obtained by two mechanical lysis methods (sonication and bead beating), associated with two distinct detergent extraction buffers, namely SDS and CHAPS. Based on gel electrophoresis-LC-MS/MS, we identified a total of 453 proteins. While lysis with glass beads provided greater amounts of protein, CHAPS extraction buffer allowed identification of a higher number of proteins compared to SDS. Our data shows the impact of different protein isolation methods in the characterization of the S. epidermidis biofilm proteome. Furthermore, the correlation between proteomic and transcriptomic profiles was evaluated. The results confirmed that proteomic and transcriptomic data should be analyzed simultaneously in order to have a comprehensive understanding of a specific microbiological condition.
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Affiliation(s)
- Virginia Carvalhais
- CEB-Centre of Biological Engineering, LIBRO - Laboratory of Research in Biofilms Rosário Oliveira, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; QOPNA, Mass Spectrometry Center, Department of Chemistry, University of Aveiro, Aveiro, Portugal; Division of Infectious diseases, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Angela França
- CEB-Centre of Biological Engineering, LIBRO - Laboratory of Research in Biofilms Rosário Oliveira, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; Division of Infectious diseases, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Gerald B Pier
- Division of Infectious diseases, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Manuel Vilanova
- ICBAS-Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal; IBMC-Instituto de Biologia Molecular e Celular, Rua do Campo Alegre 83, Porto, Portugal
| | - Nuno Cerca
- CEB-Centre of Biological Engineering, LIBRO - Laboratory of Research in Biofilms Rosário Oliveira, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Rui Vitorino
- QOPNA, Mass Spectrometry Center, Department of Chemistry, University of Aveiro, Aveiro, Portugal.
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Fischer A, Kambara K, Meyer H, Stenz L, Bonetti EJ, Girard M, Lalk M, Francois P, Schrenzel J. GdpS contributes to Staphylococcus aureus biofilm formation by regulation of eDNA release. Int J Med Microbiol 2014; 304:284-99. [DOI: 10.1016/j.ijmm.2013.10.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 10/25/2013] [Accepted: 10/27/2013] [Indexed: 11/30/2022] Open
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Mhatre E, Monterrosa RG, Kovács AT. From environmental signals to regulators: modulation of biofilm development in Gram-positive bacteria. J Basic Microbiol 2014; 54:616-32. [PMID: 24771632 DOI: 10.1002/jobm.201400175] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 03/30/2014] [Indexed: 12/22/2022]
Abstract
Bacterial lifestyle is influenced by environmental signals, and many differentiation processes in bacteria are governed by the threshold concentrations of molecules present in their niche. Biofilm is one such example where bacteria in their sessile state adapt to a lifestyle that causes several adaptive alterations in the population. Here, a brief overview is given on a variety of environmental signals that bias biofilm development in Gram-positive bacteria, including nutrient conditions, self- and heterologously produced substances, like quorum sensing and host produced molecules. The Gram-positive model organism, Bacillus subtilis is a superb example to illustrate how distinct signals activate sensor proteins that integrate the environmental signals towards global regulators related to biofilm formation. The role of reduced oxygen level, polyketides, antimicrobials, plant secreted carbohydrates, plant cell derived polymers, glycerol, and osmotic conditions are discussed during the transcriptional activation of biofilm related genes in B. subtilis.
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Affiliation(s)
- Eisha Mhatre
- Terrestrial Biofilms Group, Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany
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48
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You Y, Xue T, Cao L, Zhao L, Sun H, Sun B. Staphylococcus aureus glucose-induced biofilm accessory proteins, GbaAB, influence biofilm formation in a PIA-dependent manner. Int J Med Microbiol 2014; 304:603-12. [PMID: 24836943 DOI: 10.1016/j.ijmm.2014.04.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Revised: 03/28/2014] [Accepted: 04/19/2014] [Indexed: 10/25/2022] Open
Abstract
The Gram-positive bacteria Staphylococcus aureus and Staphylococcus epidermidis are capable of attaching to a biomaterial surface and forming resistant biofilms. The identification of biomolecular and regulatory factors involved in staphylococcal adhesion and biofilm formation is needed to understand biofilm-associated infection in humans. Here, we have identified a new operon, gbaAB (glucose induced biofilm accessory gene), that affects biofilm formation in S. aureus NCTC8325. Real-time reverse transcription PCR (RT-PCR) and electrophoretic mobility shift assay showed that GbaA and GbaB are transcribed from the same transcript, and GbaA directly inhibits the transcription of the gbaAB operon through self-repression. Our results indicated that the gbaA mutant displayed enhanced biofilm formation compared with the wild type. However, the gbaB and the gbaAB double mutant displayed reduced biofilm formation, suggesting that the gbaAB operon is involved in biofilm formation and that gbaB might be the key gene in biofilm regulation. Phenotypic analysis suggested that the gbaAB operon mediated biofilm formation of S. aureus at the multicellular aggregation stage rather than during initial attachment. In addition, real-time RT-PCR analysis showed that icaA was upregulated in the gbaA mutant and downregulated in the gbaB and gbaAB mutants compared with the wild type. In addition, the gbaA and the gbaB mutants affected the induction of biofilm formation by glucose. Our results suggest that the gbaAB operon is involved in the regulation of the multicellular aggregation step of S. aureus biofilm formation in response to glucose and that this regulation may be mediated through the ica operon.
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Affiliation(s)
- Yibo You
- Department of Microbiology and Immunology, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Ting Xue
- Department of Microbiology and Immunology, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Linyan Cao
- Department of Microbiology and Immunology, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Liping Zhao
- Department of Microbiology and Immunology, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Haipeng Sun
- Department of Microbiology and Immunology, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Baolin Sun
- Department of Microbiology and Immunology, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China.
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Fux CA, Stoodley P, Hall-Stoodley L, Costerton JW. Bacterial biofilms: a diagnostic and therapeutic challenge. Expert Rev Anti Infect Ther 2014; 1:667-83. [PMID: 15482163 DOI: 10.1586/14787210.1.4.667] [Citation(s) in RCA: 172] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Bacteria have traditionally been regarded as individual organisms growing in homogeneous planktonic populations. However, bacteria in natural environments usually form communities of surface-adherent organisms embedded in an extracellular matrix, called biofilms. Current antimicrobial strategies often fail to control bacteria in the biofilm mode of growth. Treatment failure is particularly frequent in association with intracorporeal or transcutaneous medical devices and compromised host immunity. The rising prevalence of these risk factors over the last decades has paralleled the increase in biofilm infections. This review discusses the shortcomings of current therapies against biofilms both in theory and with clinical examples. Biofilm characteristics are described with a focus on new diagnostic and therapeutic targets.
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Affiliation(s)
- Christoph A Fux
- Center for Biofilm Engineering, Montana State University, USA.
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50
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Hodgson SD, Greco-Stewart V, Jimenez CS, Sifri CD, Brassinga AKC, Ramirez-Arcos S. Enhanced pathogenicity of biofilm-negative Staphylococcus epidermidis isolated from platelet preparations. Transfusion 2013; 54:461-70. [PMID: 23795974 DOI: 10.1111/trf.12308] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 04/22/2013] [Accepted: 04/29/2013] [Indexed: 12/18/2022]
Abstract
BACKGROUND The platelet (PLT) storage environment triggers the formation of surface-attached aggregates known as biofilms by the common PLT contaminant Staphylococcus epidermidis. The biofilm matrix is largely composed of polysaccharide intercellular adhesin (PIA) mediated by the icaADBC operon. However, PIA-negative S. epidermidis has been reported to form biofilms in PLT concentrates (PCs). Since biofilm formation is associated with increased virulence, this study was aimed at determining if PIA-negative S. epidermidis grown in PCs presents enhanced virulence using the nematode Caenorhabditis elegans as a host model for bacterial pathogenesis. STUDY DESIGN AND METHODS Biofilm-positive S. epidermidis ATCC 35984 and 9142, which carry the icaADBC operon, and biofilm-negative S. epidermidis ATCC 12228 and 9142 ΔicaA were grown in regular media and in PCs and biofilm formation was quantified using a crystal violet assay. The virulence of these strains after passage through PCs was tested using nematode killing assays. Nematode survival was calculated using the Kaplan-Meier method and statistical differences were determined by log-rank analysis. RESULTS All S. epidermidis strains were able to form biofilms in PCs. Although persistence of a biofilm-positive phenotype in the biofilm-negative strains grown in PCs was not observed after passage in regular medium, the virulence of all strains was significantly increased as demonstrated by shortened life spans of the nematodes in C. elegans killing assays. CONCLUSION Our findings highlight the potential of an increased risk of nosocomial infections caused by S. epidermidis in transfusion recipients since PC storage conditions promote biofilm formation, and possibly pathogenicity, of strains traditionally known to be attenuated for virulence.
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Affiliation(s)
- Scott D Hodgson
- Department of Microbiology, Faculty of Science, University of Manitoba, Winnipeg, Manitoba, Canada; Division of Infectious Diseases and International Health, Department of Medicine, University of Virginia Health System, Charlottesville, Virginia; Canadian Blood Services, Ottawa, Ontario, Canada
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