scholarly journals Synergistic Activity of Dispersin B and Cefamandole Nafate in Inhibition of Staphylococcal Biofilm Growth on Polyurethanes

2007 ◽  
Vol 51 (8) ◽  
pp. 2733-2740 ◽  
Author(s):  
G. Donelli ◽  
I. Francolini ◽  
D. Romoli ◽  
E. Guaglianone ◽  
A. Piozzi ◽  
...  
Keyword(s):  
Medical Devices ◽  
Bacterial Colonization ◽  
Bacterial Species ◽  
Hydrolytic Activity ◽  
Polymer Surfaces ◽  
Periodontal Pathogen ◽  
Synergistic Activity ◽  
Biofilm Growth ◽  
Microbial Biofilms ◽  
Alternative Approaches

ABSTRACT Antibiotic therapies to eradicate medical device-associated infections often fail because of the ability of sessile bacteria, encased in their exopolysaccharide matrix, to be more drug resistant than planktonic organisms. In the last two decades, several strategies to prevent microbial adhesion and biofilm formation on the surfaces of medical devices, based mainly on the use of antiadhesive, antiseptic, and antibiotic coatings on polymer surfaces, have been developed. More recent alternative approaches are based on molecules able to interfere with quorum-sensing phenomena or to dissolve biofilms. Interestingly, a newly purified β-N-acetylglucosaminidase, dispersin B, produced by the gram-negative periodontal pathogen Actinobacillus actinomycetemcomitans, is able to dissolve mature biofilms produced by Staphylococcus epidermidis as well as some other bacterial species. Therefore, in this study, we developed new polymeric matrices able to bind dispersin B either alone or in combination with an antibiotic molecule, cefamandole nafate (CEF). We showed that our functionalized polyurethanes could adsorb a significant amount of dispersin B, which was able to exert its hydrolytic activity against the exopolysaccharide matrix produced by staphylococcal strains. When microbial biofilms were exposed to both dispersin B and CEF, a synergistic action became evident, thus characterizing these polymer-dispersin B-antibiotic systems as promising, highly effective tools for preventing bacterial colonization of medical devices.

scholarly journals Graphene-Based Sensor for Detection of Bacterial Pathogens

Sensors ◽  
2021 ◽  
Vol 21 (23) ◽  
pp. 8085
Author(s):  
Santosh Pandit ◽  
Mengyue Li ◽  
Yanyan Chen ◽  
Shadi Rahimi ◽  
Vrss Mokkapati ◽  
...  
Keyword(s):  
Antimicrobial Agents ◽  
Bacterial Colonization ◽  
Bacterial Species ◽  
Complex Structure ◽  
Growth Dynamics ◽  
Microbial Colonization ◽  
Bacterial Cells ◽  
Resistance Change ◽  
Biofilm Growth ◽  
Adherence Pattern

Microbial colonization to biomedical surfaces and biofilm formation is one of the key challenges in the medical field. Recalcitrant biofilms on such surfaces cause serious infections which are difficult to treat using antimicrobial agents, due to their complex structure. Early detection of microbial colonization and monitoring of biofilm growth could turn the tide by providing timely guidance for treatment or replacement of biomedical devices. Hence, there is a need for sensors, which could generate rapid signals upon bacterial colonization. In this study, we developed a simple prototype sensor based on pristine, non-functionalized graphene. The detection principle is a change in electrical resistance of graphene upon exposure to bacterial cells. Without functionalization with specific receptors, such sensors cannot be expected to be selective to certain bacteria. However, we demonstrated that two different bacterial species can be detected and differentiated by our sensor due to their different growth dynamics, adherence pattern, density of adhered bacteria and microcolonies formation. These distinct behaviors of tested bacteria depicted distinguishable pattern of resistance change, resistance versus gate voltage plot and hysteresis effect. This sensor is simple to fabricate, can easily be miniaturized, and can be effective in cases when precise identification of species is not needed.

scholarly journals The presence of biofilm forming microorganisms on hydrotherapy equipment and facilities

2017 ◽  
Vol 15 (6) ◽  
pp. 923-931 ◽  
Author(s):  
Natalia Jarząb ◽  
Maciej Walczak
Keyword(s):  
Medical Devices ◽  
Biofilm Formation ◽  
Stenotrophomonas Maltophilia ◽  
Pathogenic Bacteria ◽  
Hydrolytic Activity ◽  
Opportunistic Pathogens ◽  
Influence Of Temperature ◽  
Laboratory Conditions ◽  
Microbial Biofilms ◽  
Brine Pool

Abstract Hydrotherapy equipment provides a perfect environment for the formation and growth of microbial biofilms. Biofilms may reduce the microbiological cleanliness of hydrotherapy equipment and harbour opportunistic pathogens and pathogenic bacteria. The aims of this study were to investigate the ability of microorganisms that colonize hydrotherapy equipment to form biofilms, and to assess the influence of temperature and nutrients on the rate of biofilm formation. Surface swab samples were collected from the whirlpool baths, inhalation equipment and submerged surfaces of a brine pool at the spa center in Ciechocinek, Poland. We isolated and identified microorganisms from the swab samples and measured their ability to form biofilms. Biofilm formation was observed at a range of temperatures, in both nutrient-deficient and nutrient-rich environments. We isolated and identified microorganisms which are known to form biofilms on medical devices (e.g. Stenotrophomonas maltophilia). All isolates were classified as opportunistic pathogens, which can cause infections in humans with weakened immunity systems. All isolates showed the ability to form biofilms in the laboratory conditions. The potential for biofilm formation was higher in the presence of added nutrients. In addition, the hydrolytic activity of the biofilm was connected with the presence of nutrients.

Anti-biofilm activity of a semi-synthetic molecule obtained from resveratrol against Candida albicans biofilm

2019 ◽  
Vol 58 (4) ◽  
pp. 530-542 ◽  
Author(s):  
Camille Juin ◽  
Flavie Perrin ◽  
Thomas Puy ◽  
Clément Bernard ◽  
Marie Laure Mollichella ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Medical Devices ◽  
Antifungal Agents ◽  
Optimal Combination ◽  
Synergistic Activity ◽  
Strain Atcc ◽  
Biofilm Growth ◽  
Cell Counts ◽  
Synergistic Relationship ◽  
Synthetic Molecule

Abstract Candida albicans can form biofilm on tissues and medical devices, becoming, in that case, less susceptible to antifungal agents. Treatment of candidiasis associated with the formation of C. albicans biofilms is restricted to echinocandins and lipid forms of amphotericin B. This study investigated the activity of micafungin and resveratrol modified molecule (EB487) against C. albicans biofilms. The anti-biofilm growth (Bgrowth) and anti-preformed biofilm (Bpreformed) activities of micafungin (0 to 3.94 μM) and EB487 (0 to 20.32 mM) were comparatively studied separately and combined, using XTT, flow cytometry and cell counts approaches. Concentrations causing 50% inhibition of the studied steps (IC50) were evaluated. When tested separately, IC50 Bgrowth was obtained for 4.8 mM and 0.13 μM of EB487 and micafungin respectively, and IC50 Bpreformed for 3.6 mM and 0.06 μM of EB487 and micafungin respectively. Micafungin used alone was not able to totally eradicate fungi. Micafungin combined with EB487 displayed synergistic activity (both anti-growth- and anti-preformed biofilm-activities). Optimal combination concentrations were EB487 (≤9.12 mM -strain ATCC 28367™ or ≤8.12 mM -strain CAI4-p), micafungin (≤0.05 μM for both) and caused a total eradication of fungi. Dose reduction indexes obtained using these concentrations were at least 9 (micafungin) and 3.2 (EB487) for both anti-biofilm growth- and anti-preformed biofilm-activities. Combinations indexes were consistently below one, demonstrating a synergistic relationship between micafungin and EB487 in these conditions. This study demonstrated the strong anti-biofilm activity of EB487 and highlighted its synergistic potential when combined with micafungin. EB487 is a promising semi-synthetic molecule with prophylactic and curative interests in fighting C. albicans biofilms.

scholarly journals Bacteriophage Cocktail-Mediated Inhibition of Pseudomonas aeruginosa Biofilm on Endotracheal Tube Surface

Antibiotics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 78
Author(s):  
Viviane C. Oliveira ◽  
Ana P. Macedo ◽  
Luís D. R. Melo ◽  
Sílvio B. Santos ◽  
Paula R. S. Hermann ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Endotracheal Tube ◽  
Metabolic Activity ◽  
Bacterial Colonization ◽  
Multidrug Resistant ◽  
Scientific Data ◽  
Tube Surface ◽  
Screening Assay ◽  
Biofilm Growth ◽  
Phage Cocktail

Although different strategies to control biofilm formation on endotracheal tubes have been proposed, there are scarce scientific data on applying phages for both removing and preventing Pseudomonas aeruginosa biofilms on the device surface. Here, the anti-biofilm capacity of five bacteriophages was evaluated by a high content screening assay. We observed that biofilms were significantly reduced after phage treatment, especially in multidrug-resistant strains. Considering the anti-biofilm screens, two phages were selected as cocktail components, and the cocktail’s ability to prevent colonization of the endotracheal tube surface was tested in a dynamic biofilm model. Phage-coated tubes were challenged with different P. aeruginosa strains. The biofilm growth was monitored from 24 to 168 h by colony forming unit counting, metabolic activity assessment, and biofilm morphology observation. The phage cocktail promoted differences of bacterial colonization; nonetheless, the action was strain dependent. Phage cocktail coating did not promote substantial changes in metabolic activity. Scanning electron microscopy revealed a higher concentration of biofilm cells in control, while tower-like structures could be observed on phage cocktail-coated tubes. These results demonstrate that with the development of new coating strategies, phage therapy has potential in controlling the endotracheal tube-associated biofilm.

scholarly journals Relevance of Biofilm Models in Periodontal Research: From Static to Dynamic Systems

2021 ◽  
Vol 9 (2) ◽  
pp. 428
Author(s):  
María Carmen Sánchez ◽  
Andrea Alonso-Español ◽  
Honorato Ribeiro-Vidal ◽  
Bettina Alonso ◽  
David Herrera ◽  
...  
Keyword(s):  
Research Group ◽  
Surface Composition ◽  
Bacterial Colonization ◽  
Implant Surface ◽  
Biofilm Growth ◽  
Biofilm Model ◽  
Dental Implant Surface ◽  
The Impact

Microbial biofilm modeling has improved in sophistication and scope, although only a limited number of standardized protocols are available. This review presents an example of a biofilm model, along with its evolution and application in studying periodontal and peri-implant diseases. In 2011, the ETEP (Etiology and Therapy of Periodontal and Peri-Implant Diseases) research group at the University Complutense of Madrid developed an in vitro biofilm static model using representative bacteria from the subgingival microbiota, demonstrating a pattern of bacterial colonization and maturation similar to in vivo subgingival biofilms. When the model and its methodology were standardized, the ETEP research group employed the validated in vitro biofilm model for testing in different applications. The evolution of this model is described in this manuscript, from the mere observation of biofilm growth and maturation on static models on hydroxyapatite or titanium discs, to the evaluation of the impact of dental implant surface composition and micro-structure using the dynamic biofilm model. This evolution was based on reproducing the ideal microenvironmental conditions for bacterial growth within a bioreactor and reaching the target surfaces using the fluid dynamics mimicking the salivary flow. The development of this relevant biofilm model has become a powerful tool to study the essential processes that regulate the formation and maturation of these important microbial communities, as well as their behavior when exposed to different antimicrobial compounds.

Physical methods for controlling bacterial colonization on polymer surfaces

2020 ◽  
Vol 43 ◽  
pp. 107586 ◽  
Author(s):  
Coro Echeverria ◽  
Marcelo Der Torossian Torres ◽  
Marta Fernández-García ◽  
Cesar de la Fuente-Nunez ◽  
Alexandra Muñoz-Bonilla
Keyword(s):  
Bacterial Colonization ◽  
Polymer Surfaces ◽  
Physical Methods

scholarly journals Evaluation of Antibacterial Effects of Fissure Sealants Containing Chitosan Nanoparticles

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Sedighe Sadat Hashemi kamangar ◽  
Houtan Zareian ◽  
Abbas Bahador ◽  
Maryam Pourhajibagher ◽  
Zahra Bashareh ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Antibacterial Effect ◽  
Bacterial Species ◽  
Chitosan Nanoparticles ◽  
Control Group ◽  
Fissure Sealants ◽  
Biofilm Inhibition ◽  
Biofilm Growth ◽  
Fissure Sealant ◽  
Significant Difference

Objectives. The present study evaluated the antimicrobial effects of fissure sealants containing chitosan nanoparticles. Materials and Methods. Antibacterial effect of Master Dent fissure sealant alone and after incorporating chitosan nanoparticles was evaluated on Streptococcus mutans, sanguis, and Lactobacillus acidophilus. Biofilm growth was evaluated by determining colony counts. Antimicrobial effect was determined on days 3, 15, and 30 by counting microbial colonies using eluted components test. One-way ANOVA, Tukey HSD tests, t test, and two-way ANOVA were used for statistical analyses (α = 0.05). Results. Biofilm inhibition test showed that fissure sealant containing 1 wt.% chitosan decreased colony counts significantly ( P < 0.05 ). Eluted components test with S. mutans and sanguis showed significant decrease in colony counts during the first 15 days in chitosan containing group; however, from day 30, antimicrobial activity decreased noticeably, with no significant difference from control group ( P > 0.05 ). Antimicrobial activity against L. acidophilus was maintained in chitosan group up to 30 days, and decrease in colony counts was significant ( P < 0.05 ). Conclusion. According to the results of this study, incorporation of 1 wt.% chitosan into fissure sealant induced an antimicrobial activity. Antibacterial effect on L. acidophilus persisted for longer time (30 days) compared to the two other bacterial species (15 days).

scholarly journals Understanding How Staphylococcal Autolysin Domains Interact With Polystyrene Surfaces

2021 ◽  
Vol 12 ◽  
Author(s):  
Radha P. Somarathne ◽  
Emily R. Chappell ◽  
Y. Randika Perera ◽  
Rahul Yadav ◽  
Joo Youn Park ◽  
...  
Keyword(s):  
Secondary Structure ◽  
Medical Devices ◽  
Biofilm Formation ◽  
Limited Proteolysis ◽  
Cd Spectroscopy ◽  
Bacterial Attachment ◽  
Binding Interaction ◽  
Biofilm Growth ◽  
Source Of Infection ◽  
Structural Details

Biofilms, when formed on medical devices, can cause malfunctions and reduce the efficiency of these devices, thus complicating treatments and serving as a source of infection. The autolysin protein of Staphylococcus epidermidis contributes to its biofilm forming ability, especially on polystyrene surfaces. R2ab and amidase are autolysin protein domains thought to have high affinity to polystyrene surfaces, and they are involved in initial bacterial attachment in S. epidermidis biofilm formation. However, the structural details of R2ab and amidase binding to surfaces are poorly understood. In this study, we have investigated how R2ab and amidase influence biofilm formation on polystyrene surfaces. We have also studied how these proteins interact with polystyrene nanoparticles (PSNPs) using biophysical techniques. Pretreating polystyrene plates with R2ab and amidase domains inhibits biofilm growth relative to a control protein, indicating that these domains bind tightly to polystyrene surfaces and can block bacterial attachment. Correspondingly, we find that both domains interact strongly with anionic, carboxylate-functionalized as well as neutral, non-functionalized PSNPs, suggesting a similar binding interaction for nanoparticles and macroscopic surfaces. Both anionic and neutral PSNPs induce changes to the secondary structure of both R2ab and amidase as monitored by circular dichroism (CD) spectroscopy. These changes are very similar, though not identical, for both types of PSNPs, suggesting that carboxylate functionalization is only a small perturbation for R2ab and amidase binding. This structural change is also seen in limited proteolysis experiments, which exhibit substantial differences for both proteins when in the presence of carboxylate PSNPs. Overall, our results demonstrate that the R2ab and amidase domains strongly favor adsorption to polystyrene surfaces, and that surface adsorption destabilizes the secondary structure of these domains. Bacterial attachment to polystyrene surfaces during the initial phases of biofilm formation, therefore, may be mediated by aromatic residues, since these residues are known to drive adsorption to PSNPs. Together, these experiments can be used to develop new strategies for biofilm eradication, ensuring the proper long-lived functioning of medical devices.

scholarly journals The Antibiofilm Activity of Dual-Function Tail Tubular Protein B from KP32 Phage

2018 ◽  
Author(s):  
Ewa Brzozowska ◽  
Anna Pyra ◽  
Krzysztof Pawlik ◽  
Sabina Górska ◽  
Andrzej Gamian
Keyword(s):  
Klebsiella Pneumoniae ◽  
Enterococcus Faecalis ◽  
Biofilm Formation ◽  
Hydrolytic Activity ◽  
Bacterial Biofilm ◽  
Dual Function ◽  
Antibiofilm Activity ◽  
Synergistic Activity ◽  
Antibiotic Action ◽  
Phage Protein

Background: Dual function tail tubular proteins (TTP) belonging to the lytic bacteriophages are the interesting group of biologically active enzymes. Surprisingly, apart from their structural function, they are also polysaccharide hydrolyzes destroying bacterial extracellular components. One of the representatives of this group is TTPB from Klebsiella pneumoniae phage &ndash; KP32. TTPB hydrolyzes exopolysaccharide (EPS) of Klebsiella pneumoniae and Enterococcus faecalis strain. This depolymerizing feature was associated with the activity to prevent bacterial biofilm formation. TTPB can inhibit biofilm formation by K. pneumoniae, Enterobacter cloacae, Staphylococcus aureus, Enterococcus faecalis and Pseudomonas aeruginosa strains. Moreover, synergistic activity with antibiotic action has been observed, most likely due to depolymerases&rsquo; facilitation of contact of antibiotic with bacterial cells. Methods: TTPB was overexpressed in E coli system, purified and tested towards the bacterial strains using agar overlay method. The hydrolytic activity of TTPB was performed using EPSs of K. pneumoniae PCM2713 and E. cloacae ATCC 13047 as the substrates. Next, we determined the reducing sugar (RS) levels in the TTPB/EPS mixtures, regarding the RS amount obtained after acidic hydrolysis. The antibiofilm activity of TTPB has been set down on bacterial biofilm using a biochemical method. Finally, we have demonstrated the synergistic activity of TTPB with kanamycin. Results: For the first time, the hydrolytic activity of TTPB towards bacterial EPSs has been shown. TTPB releases about a half of the whole RS amount of EPSs belonging to K. pneumoniae PCM 2713 and E. cloacae ATCC 13047 strains. 1.12 &micro;M of the phage protein reduces biofilm of both strains by over 60%. Destroying the bacterial biofilm the phage protein improves the antibiotic action increasing kanamycin effectiveness up to four times.

scholarly journals The Effect of Gold and Iron-Oxide Nanoparticles on Biofilm-Forming Pathogens

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Madhu Bala Sathyanarayanan ◽  
Reneta Balachandranath ◽  
Yuvasri Genji Srinivasulu ◽  
Sathish Kumar Kannaiyan ◽  
Guruprakash Subbiahdoss
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Immune Cells ◽  
Biofilm Formation ◽  
Bacterial Infections ◽  
Medical Applications ◽  
Oxide Nanoparticles ◽  
Biofilm Growth ◽  
Microbial Biofilms ◽  
Exopolymeric Substances

Microbial biofilms on biomaterial implants or devices are hard to eliminate by antibiotics due to their protection by exopolymeric substances that embed the organisms in a matrix, impenetrable for most antibiotics and immune-cells. Application of metals in their nanoparticulated form is currently considered to resolve bacterial infections. Gold and iron-oxide nanoparticles are widely used in different medical applications, but their utilisation to eradicate biofilms on biomaterials implants is novel. Here, we studied the effect of gold and iron oxide nanoparticles on Staphylococcus aureus and Pseudomonas aeruginosa biofilms. We report that biofilm growth was reduced at higher concentrations of gold and iron-oxide nanoparticles compared to absence of nanoparticles. Thus nanoparticles with appropriate concentration could show significant reduction in biofilm formation.

Sign in / Sign up

Export Citation Format

Share Document