Formation of biofilms by representatives of the oral microflora on the surfaces of basic materials

The aim of the work is to conduct a comparative analysis of the biofilm formation by representatives of the oral microflora on the surfaces of basic materials. Materials and methods. The process of biofilm formation was examined on 7 types of basic plastic samples: Polyan, Breflex, Nylon, Protakryl, Vinakryl, Biocryl, which were used for the manufacture of removable prosthetic basis constructions, and SYNMA, which was used for comparison. Biofilm formation was analyzed by the method Y. Zhang (2017) with minor modifications. The test sample was placed in a test tube with 2.0 ml of nutrient broth Brain Heart Infusion to model the biofilm growth of microorganisms (HiMedia Laboratories Pvt. Ltd., India) supplemented with 1 % glucose, pre-inoculated with test strains at a final concentration of 1 × 104 CFU/ml. The strains were cultivated for 24 hours at a temperature of 37 °C under continuous stirring in a shaker MR-1 (SIA BIOS AN, Latvia) at 20 rpm. Evaluation of the biofilm massiveness was performed after gentian violet staining followed by elution of the stain with ethanol and registration of the eluent optical density (OD). The OD was measured with a Synergy™ HTX S1LFTA microplate multimode photometer (BioTek Instruments, Inc., USA) at 595 nm wavelength using Gen5™ Data Analysis Software. The number of viable bacterial cells in the formed biofilms was determined by the method of ten-fold serial dilutions. The obtained results were converted per unit area of the sample tested. Processing of the results was performed using a two-sample t-test with the software package Statistica 13.0 and Microsoft Office Excel, the differences were considered statistically significant at a P value of < 0.05. Statistical analysis of the obtained data was presented as mean values of measurements ± standard deviation for three independent experiments. Results. According to the microbiological analysis results it was found that α-hemolytic streptococci S. oralis and S. sanguinis showed the ability to form biofilms on the surfaces of basic materials, namely Protacryl and Vinacryl, the total biomass of S. sanguinis biofilms was 47.7 % (P < 0.01) and 14.7 % (P > 0.05) greater, respectively, in comparison to a glass slide. Inhibition of biofilm formation processes was observed on the surfaces of Nylon and Biocryl basic materials. S. oralis and S. gordonii showed the highest ability to survive in biofilms. The intensity of C. albicans biofilms formation on Biocryl basic materials, comparative plastics SINMA and Breflex basic materials was greater than on glass slides by 48.3 %, 43.0 % and 34.9 % (P < 0.01), respectively. The least massive C. albicans biofilms were formed on Breflex surfaces and SINMA comparative plastics in comparison to glass slides by 33.6 % and 24.8 % (P < 0.01), respectively. Both Candida strains had the highest level of fungal viability in biofilms on Breflex, Polyan and Protacryl basic materials (P < 0.01), and C. tropicalis biofilms on Biocryl and Vinacryl basic materials (P < 0.05). Integral coefficients indicated the inhibition of the oral microflora ability to form biofilms on the surfaces of basic materials. Conclusions. Oral α-hemolytic and β-hemolytic streptococci have the ability to intensive biofilm growth on the surfaces of the basic materials Protacryl and Vinacryl. Oral Candida albicans form massive biofilms on the surfaces of Biocryl and Vinacryl basic materials and comparative SYNMA plastics. The basic materials Breflex, Nylon and comparative plastics SYNMA are the most inert to biofilm formation by the oral microflora representatives.

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Bioinspired surfaces to delay biofilm formation: different surfaces with different mechanisms

10.5194/biofilms9-7 ◽

2020 ◽

Author(s):

Jinju Chen

Keyword(s):

Contact Angle ◽

Biofilm Formation ◽

Early Stage ◽

Contact Angle Hysteresis ◽

Antibacterial Properties ◽

Hierarchical Structures ◽

Bacterial Cells ◽

Biofilm Growth ◽

Porous Surfaces ◽

Rose Petal

Biofilm associated infections are the fourth leading cause of death worldwide, within the U.S. about 2 million annual cases lead to more than $5 billion USD in added medical costs per annum. Therefore, it is important to control biofilm growth and reduce the instances of infections.&#160; Physical strategies, in particular the use of rationally designed surface topographies or surface energies, have present us with an interesting approach to prevent bacterial adherence and biofilm growth without the requirement for antimicrobials. A variety of natural surfaces exhibit antibacterial properties. Examples of such surfaces include rose petals with hierarchical structures and Nepenthes pitcher plants with slippery liquid-infused porous surfaces. &#160; In this study, we fabricated different &#160;biomimetic surfaces (rose-petal surfaces and slippery liquid-infused porous surfaces). &#160;&#160;We have demonstrated that rose-petal surface can delay early stage P. aeruginosa and S. epidermidis biofilms formation (2 days) by about 70% and control&#160; biofilm &#160;formation according to surface structures.&#160; The mechanisms of hierarchical structures &#160;of rose-petal influence biofilm formation are two folds: 1) Papillae microstructure block &#160;the bacterial clusters in between the valleys, limiting the potential for cell-cell communication via fibrous networks, thereby resulting in impaired biofilm growth. 2) The secondary structure (nano-folds) on microstructures can align bacterial cells within the constrained grooves, thereby delaying cell clusters formation during short term growth of biofilm. While, the slippery liquid-infused porous surface(s) can prevent over 90% P. aeruginosa and S. epidermidis biofilms formation for a duration of 6 days.&#160; These are mainly attributed to their high contact angle and extreme low contact angle hysteresis.

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Deciphering Streptococcal Biofilms

Microorganisms ◽

10.3390/microorganisms8111835 ◽

2020 ◽

Vol 8 (11) ◽

pp. 1835

Author(s):

Puja Yadav ◽

Shalini Verma ◽

Richard Bauer ◽

Monika Kumari ◽

Meenakshi Dua ◽

...

Keyword(s):

Environmental Conditions ◽

Biofilm Formation ◽

Expression Patterns ◽

Initial Step ◽

Molecular Techniques ◽

Surface Proteins ◽

Considerable Proportion ◽

Bacterial Cells ◽

Bacterial Survival ◽

Biofilm Growth

Streptococci are a diverse group of bacteria, which are mostly commensals but also cause a considerable proportion of life-threatening infections. They colonize many different host niches such as the oral cavity, the respiratory, gastrointestinal, and urogenital tract. While these host compartments impose different environmental conditions, many streptococci form biofilms on mucosal membranes facilitating their prolonged survival. In response to environmental conditions or stimuli, bacteria experience profound physiologic and metabolic changes during biofilm formation. While investigating bacterial cells under planktonic and biofilm conditions, various genes have been identified that are important for the initial step of biofilm formation. Expression patterns of these genes during the transition from planktonic to biofilm growth suggest a highly regulated and complex process. Biofilms as a bacterial survival strategy allow evasion of host immunity and protection against antibiotic therapy. However, the exact mechanisms by which biofilm-associated bacteria cause disease are poorly understood. Therefore, advanced molecular techniques are employed to identify gene(s) or protein(s) as targets for the development of antibiofilm therapeutic approaches. We review our current understanding of biofilm formation in different streptococci and how biofilm production may alter virulence-associated characteristics of these species. In addition, we have summarized the role of surface proteins especially pili proteins in biofilm formation. This review will provide an overview of strategies which may be exploited for developing novel approaches against biofilm-related streptococcal infections.

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Effects ofBacillusSerine Proteases on the Bacterial Biofilms

BioMed Research International ◽

10.1155/2017/8525912 ◽

2017 ◽

Vol 2017 ◽

pp. 1-10 ◽

Cited By ~ 12

Author(s):

Olga Mitrofanova ◽

Ayslu Mardanova ◽

Vladimir Evtugyn ◽

Lydia Bogomolnaya ◽

Margarita Sharipova

Keyword(s):

Biofilm Formation ◽

Quantitative Methods ◽

Time Course ◽

Extracellular Polymeric Substances ◽

Proteolytic Enzymes ◽

Opportunistic Pathogen ◽

Glutamyl Endopeptidase ◽

Bacterial Cells ◽

Biofilm Growth ◽

Tract Infections

Serratia marcescensis an emerging opportunistic pathogen responsible for many hospital-acquired infections including catheter-associated bacteremia and urinary tract and respiratory tract infections. Biofilm formation is one of the mechanisms employed byS. marcescensto increase its virulence and pathogenicity. Here, we have investigated the main steps of the biofilm formation byS. marcescensSR 41-8000. It was found that the biofilm growth is stimulated by the nutrient-rich environment. The time-course experiments showed thatS. marcescenscells adhere to the surface of the catheter and start to produce extracellular polymeric substances (EPS) within the first 2 days of growth. After 7 days,S. marcescensbiofilms maturate and consist of bacterial cells embedded in a self-produced matrix of hydrated EPS. In this study, the effect ofBacillus pumilus3-19 proteolytic enzymes on the structure of 7-day-oldS. marcescensbiofilms was examined. Using quantitative methods and scanning electron microscopy for the detection of biofilm, we demonstrated a high efficacy of subtilisin-like protease and glutamyl endopeptidase in biofilm removal. Enzymatic treatment resulted in the degradation of the EPS components and significant eradication of the biofilms.

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Visible Light-Activated Carbon Dots for Inhibiting Biofilm Formation and Inactivating Biofilm-Associated Bacterial Cells

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.786077 ◽

2021 ◽

Vol 9 ◽

Author(s):

Xiuli Dong ◽

Christopher M. Overton ◽

Yongan Tang ◽

Jasmine P. Darby ◽

Ya-Ping Sun ◽

...

Keyword(s):

Visible Light ◽

Carbon Dots ◽

Biofilm Formation ◽

Chelating Agents ◽

Early Stage ◽

Inhibitory Effect ◽

Bacterial Cells ◽

Planktonic Cells ◽

Biofilm Growth ◽

Time Point

This study aimed to address the significant problems of bacterial biofilms found in medical fields and many industries. It explores the potential of classic photoactive carbon dots (CDots), with 2,2′-(ethylenedioxy)bis (ethylamine) (EDA) for dot surface functionalization (thus, EDA-CDots) for their inhibitory effect on B. subtilis biofilm formation and the inactivation of B. subtilis cells within established biofilm. The EDA-CDots were synthesized by chemical functionalization of selected small carbon nanoparticles with EDA molecules in amidation reactions. The inhibitory efficacy of CDots with visible light against biofilm formation was dependent significantly on the time point when CDots were added; the earlier the CDots were added, the better the inhibitory effect on the biofilm formation. The evaluation of antibacterial action of light-activated EDA-CDots against planktonic B. subtilis cells versus the cells in biofilm indicate that CDots are highly effective for inactivating planktonic cells but barely inactivate cells in established biofilms. However, when coupling with chelating agents (e.g., EDTA) to target the biofilm architecture by breaking or weakening the EPS protection, much enhanced photoinactivation of biofilm-associated cells by CDots was achieved. The study demonstrates the potential of CDots to prevent the initiation of biofilm formation and to inhibit biofilm growth at an early stage. Strategic combination treatment could enhance the effectiveness of photoinactivation by CDots to biofilm-associated cells.

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EFFECT OF TOBACCO EXTRACT ON STREPTOCOCCUS MUTANS: POSSIBLE ROLE IN MODULATING CARCINOGENESIS

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2018.v11i7.25425 ◽

2018 ◽

Vol 11 (7) ◽

pp. 398

Author(s):

Jyotsna Arun ◽

Srikant N ◽

Ethel Suman ◽

Ashok Shenoy ◽

Srikala Baliga

Keyword(s):

Carbon Dioxide ◽

Streptococcus Mutans ◽

Biofilm Formation ◽

Brain Heart Infusion ◽

Colony Growth ◽

Oral Microflora ◽

The World ◽

Tobacco Extract ◽

Acetaldehyde Production ◽

One Way Anova

Objective: Tobacco use in the smoking or smokeless form is the most common form of substance abuse recorded in the world. Not only does tobacco influence carcinogenesis but also modifies the oral microflora. The aim of our study was to assess the growth pattern of Streptococcus mutans under the influence of cigarette extract.Methods: Pure stock culture of S. mutans was grown in brain heart infusion broth mixed with three concentrations of aqueous cigarette extract. Quantification of the S. mutans colonies was performed in Mitis Salivarius Agar subculture. Biofilm assessment was also performed to find the adherent property of microorganisms.Statistical Analysis used: One-way ANOVA was used to compare the effect of cigarette extract on growth and biofilm formation of S. mutans. Results: There was increase in the colony counts with increasing concentration of cigarette extract (p<0.001). There was an observable trend noted in the biofilm assay.Conclusion: The colony growth is positively influenced by the cigarette additives (sugars and sweeteners), carbon dioxide environment, and biofilm modification. The altered flora with higher S. mutans may be linked with the higher salivary acetaldehyde production which promotes carcinogenesis. The flora may be protective by production of antitumorigenic or antimutagenic compounds. The balance between the carcinogenic and anticarcinogenic signals produced by tobacco and microflora influences the outcome of the disease.

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Low-Field Nuclear Magnetic Resonance Characteristics of Biofilm Development Process

Microorganisms ◽

10.3390/microorganisms9122466 ◽

2021 ◽

Vol 9 (12) ◽

pp. 2466

Author(s):

Yajun Zhang ◽

Yusheng Lin ◽

Xin Lv ◽

Aoshu Xu ◽

Caihui Feng ◽

...

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Biofilm Formation ◽

Development Process ◽

Bacterial Cells ◽

T2 Relaxation ◽

Biofilm Growth ◽

Low Field ◽

Biofilm Development ◽

Nuclear Magnetic

To in situ and noninvasively monitor the biofilm development process by low-field nuclear magnetic resonance (NMR), experiments should be made to determine the mechanisms responsible for the T2 signals of biofilm growth. In this paper, biofilms were cultivated in both fluid media and saturated porous media. T2 relaxation for each sample was measured to investigate the contribution of the related processes to T2 relaxation signals. In addition, OD values of bacterial cell suspensions were measured to provide the relative number of bacterial cells. We also obtained SEM photos of the biofilms after vacuum freeze-drying the pure sand and the sand with biofilm formation to confirm the space within the biofilm matrix and identify the existence of biofilm formation. The T2 relaxation distribution is strongly dependent on the density of the bacterial cells suspended in the fluid and the stage of biofilm development. The peak time and the peak percentage can be used as indicators of the biofilm growth states.

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Effect of Delmopinol on the Cohesion of Glucan-containing Plaque Formed by Streptococcus mutans in a Flow Cell System

Journal of Dental Research ◽

10.1177/00220345920710110501 ◽

1992 ◽

Vol 71 (11) ◽

pp. 1792-1796 ◽

Cited By ~ 24

Author(s):

J. Rundegren ◽

T. Simonsson ◽

L. Petersson ◽

E. Hansson

Keyword(s):

Streptococcus Mutans ◽

Electron Micrographs ◽

Amorphous Material ◽

Brain Heart Infusion ◽

Cell System ◽

Scanning Electron Micrographs ◽

Bacterial Cells ◽

Glass Slides ◽

Glucan Synthesis ◽

Delmopinol Hydrochloride

Glucan-containing plaque was formed by Streptococcus mutans adhering to saliva-coated glass slides in flow cells thermostated at 37°C. The substrate was Brain Heart Infusion broth containing 1% sucrose and 10% sterile saliva. During the build-up of the plaque, which lasted for 29 h, the plaque was subjected to three two-minute exposures to either 0.1 mol/L sodium acetate buffer, pH 6.0, or the same buffer containing 6.4 mmol/L (0.2%) of the surface-active anti-plaque substance delmopinol hydrochloride. The glass slides carrying the plaque were weighed, and plaques subjected to delmopinol treatment weighed only seven percent of the control plaques. The glass slides were then mounted in a beaker containing buffer, subjected to ultrasonication, and re-weighed. The delmopinol-treated plaques lost 59% of their wet weight upon sonication, while the controls lost only 19%. Control plaques having the same weight as delmopinol-treated plaques were not different from the control plaques grown for 29 h with regard to reduction of plaque weight after sonication. Transmission electron micrographs (TEM) showed a plaque dominated by globular or fibrillar matrix components in controls, while the delmopinol-treated plaque showed empty or unordered matrix areas between more densely packed cells. The TEM results were confirmed by scanning electron micrographs, which showed amorphous material associated with the bacterial cells in the control but not in the delmopinol-treated plaque. In conclusion, delmopinol reduced surface-associated glucan synthesis and lowered the cohesion of the plaque, indicating that glucan-containing plaque formed during repeated rinsings with delmopinol may be easier to remove by mechanical means than a non-treated plaque of this type.

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Beneficial biofilms: A mini-review of strategies to enhance biofilm formation for biotechnological applications

Applied and Environmental Microbiology ◽

10.1128/aem.01994-21 ◽

2021 ◽

Author(s):

Mayur Mukhi ◽

A. S. Vishwanathan

Keyword(s):

Biofilm Formation ◽

Environmental Remediation ◽

Extracellular Polymeric Substances ◽

External Environment ◽

Bacterial Cells ◽

Biotechnological Applications ◽

Biofilm Growth ◽

Research Attention ◽

Signaling Systems ◽

Biofilm Development

The capacity of bacteria to form biofilms is an important trait for their survival and persistence. Biofilms occur naturally in soil and aquatic environments, are associated with animals ranging from insects to humans and are also found in built environments. They are typically encountered as a challenge in healthcare, food industry, and water supply ecosystems. In contrast, they are known to play a key role in the industrial production of commercially valuable products, environmental remediation processes, and in microbe-catalysed electrochemical systems for energy and resource recovery from wastewater. While there are many recent articles on biofilm control and removal, review articles on promoting biofilm growth for biotechnological applications are unavailable. Biofilm formation is a tightly regulated response to perturbations in the external environment. The multi-stage process, mediated by an assortment of proteins and signaling systems, involves the attachment of bacterial cells to a surface followed by their aggregation in a matrix of extracellular polymeric substances. Biofilms can be promoted by altering the external environment in a controlled manner, supplying molecules that trigger the aggregation of cells and engineering genes associated with biofilm development. This mini-review synthesizes findings from studies that have described such strategies and highlights areas needing research attention.

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Polysaccharides and Proteins Added to Flowing Drinking Water at Microgram-per-Liter Levels Promote the Formation of Biofilms Predominated by Bacteroidetes and Proteobacteria

Applied and Environmental Microbiology ◽

10.1128/aem.04105-13 ◽

2014 ◽

Vol 80 (8) ◽

pp. 2360-2371 ◽

Cited By ~ 25

Author(s):

Eveline L. W. Sack ◽

Paul W. J. J. van der Wielen ◽

Dick van der Kooij

Keyword(s):

Drinking Water ◽

Biofilm Formation ◽

Distribution Systems ◽

Heterotrophic Bacteria ◽

Tap Water ◽

Rrna Gene ◽

Bacterial Cells ◽

Catabolic Repression ◽

Biofilm Growth ◽

Content Type

ABSTRACTBiopolymers are important substrates for heterotrophic bacteria in (ultra)oligotrophic freshwater environments, but information about their utilization at microgram-per-liter levels by attached freshwater bacteria is lacking. This study aimed at characterizing biopolymer utilization in drinking-water-related biofilms by exposing such biofilms to added carbohydrates or proteins at 10 μg C liter−1in flowing tap water for up to 3 months. Individually added amylopectin was not utilized by the biofilms, whereas laminarin, gelatin, and caseinate were. Amylopectin was utilized during steady-state biofilm growth with simultaneously added maltose but not with simultaneously added acetate. Biofilm formation rates (BFR) at 10 μg C liter−1per substrate were ranked as follows, from lowest to highest: blank or amylopectin (≤6 pg ATP cm−2day−1), gelatin or caseinate, laminarin, maltose, acetate alone or acetate plus amylopectin, and maltose plus amylopectin (980 pg ATP cm−2day−1). Terminal restriction fragment length polymorphism (T-RFLP) and 16S rRNA gene sequence analyses revealed that the predominant maltose-utilizing bacteria also dominated subsequent amylopectin utilization, indicating catabolic repression and (extracellular) enzyme induction. The accelerated BFR with amylopectin in the presence of maltose probably resulted from efficient amylopectin binding to and hydrolysis by inductive enzymes attached to the bacterial cells.Cytophagia,Flavobacteriia,Gammaproteobacteria, andSphingobacteriiagrew during polysaccharide addition, andAlpha-,Beta-, andGammaproteobacteria,Cytophagia,Flavobacteriia, andSphingobacteriiagrew during protein addition. The succession of bacterial populations in the biofilms coincided with the decrease in the specific growth rate during biofilm formation. Biopolymers can clearly promote biofilm formation at microgram-per-liter levels in drinking water distribution systems and, depending on their concentrations, might impair the biological stability of distributed drinking water.

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Process Description of an Unconventional Biofilm Formation by Bacterial Cells Autoagglutinating Through Sticky, Long, and Peritrichate Nanofibers

10.26434/chemrxiv.10001924.v1 ◽

2019 ◽

Author(s):

Yoshihide Furuichi ◽

Shogo Yoshimoto ◽

Tomohiro Inaba ◽

Nobuhiko Nomura ◽

Katsutoshi Hori

Keyword(s):

Formation Process ◽

Biofilm Formation ◽

Extracellular Polymeric Substances ◽

Waste Treatment ◽

Large Cell ◽

Dlvo Theory ◽

Bacterial Cells ◽

Chemical Production ◽

Discontinuous Surface ◽

Cell Cell

Biofilms are used in environmental biotechnologies including waste treatment and environmentally friendly chemical production. Understanding the mechanisms of biofilm formation is essential to control microbial behavior and improve environmental biotechnologies. Acinetobacter sp. Tol 5 autoagglutinate through the interaction of the long, peritrichate nanofiber protein AtaA, a trimeric autotransporter adhesin. Using AtaA, without cell growth or the production of extracellular polymeric substances, Tol 5 cells quickly form an unconventional biofilm. In this study, we investigated the formation process of this unconventional biofilm, which started with cell–cell interactions, proceeded to cell clumping, and led to the formation of large cell aggregates. The cell–cell interaction was described by DLVO theory based on a new concept, which considers two independent interactions between two cell bodies and between two AtaA fiber tips forming a virtual discontinuous surface. If cell bodies cannot collide owing to an energy barrier at low ionic strengths but approach within the interactive distance of AtaA fibers, cells can agglutinate through their contact. Cell clumping proceeds following the cluster–cluster aggregation model, and an unconventional biofilm containing void spaces and a fractal nature develops. Understanding its formation process would extend the utilization of various types of biofilms, enhancing environmental biotechnologies.

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