scholarly journals Gliding motility of a uranium tolerant Bacteroidetes bacterium Chryseobacterium sp. strain PMSZPI: Insights into the architecture of spreading colonies

2021 ◽  
Author(s):  
Devanshi Khare ◽  
Pallavi Chandwadkar ◽  
Celin Acharya
Keyword(s):  
Biofilm Formation ◽  
Nutrient Deficiency ◽  
Gliding Motility ◽  
Ecological Perspective ◽  
Cellular Organization ◽  
Solid Agar ◽  
Significant Interest ◽  
Bacteroidetes Phylum ◽  
Colony Spreading

Uranium tolerant soil bacterium Chryseobacterium sp. strain PMSZPI moved over solid agar surfaces by gliding motility thereby forming spreading colonies which is a hallmark of members of Bacteroidetes phylum. PMSZPI genome harbored orthologs of all the gld and spr genes considered as core bacteroidetes gliding motility genes of which gldK, gldL, gldM, and gldN were co-transcribed. Here, we present the intriguing interplay between gliding motility and cellular organization in PMSZPI spreading colonies. While nutrient deficiency enhanced colony spreading, high agar concentrations and presence of motility inhibitor like 5-hydroxyindole reduced the spreading. A detailed in situ structural analysis of spreading colonies revealed closely packed cells forming multiple layers at center of colony while the edges showed clusters of cells periodically arranged in hexagonal lattices interconnected with each other. The cell migration within the colony was visualized as branched structures wherein the cells were buried within extracellular matrix giving rise to fern like patterns. PMSZPI colonies exhibited strong iridescence that showed correlation with gliding motility. Presence of uranium reduced motility and iridescence and induced biofilm formation. This is a first report of gliding motility and iridescence in a bacterium from uranium enriched environment that could be of significant interest from an ecological perspective.

scholarly journals Colony spreading of the gliding bacterium Flavobacterium johnsoniae in the absence of the motility adhesin SprB

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Keiko Sato ◽  
Masami Naya ◽  
Yuri Hatano ◽  
Yoshio Kondo ◽  
Mari Sato ◽  
...  
Keyword(s):  
Soft Agar ◽  
Gliding Motility ◽  
Wild Type ◽  
Initial Cell ◽  
Flavobacterium Johnsoniae ◽  
Seeking Behavior ◽  
Colony Spreading ◽  
Gliding Bacterium ◽  
Mutant Cells ◽  
Scanning Electron

AbstractColony spreading of Flavobacterium johnsoniae is shown to include gliding motility using the cell surface adhesin SprB, and is drastically affected by agar and glucose concentrations. Wild-type (WT) and ΔsprB mutant cells formed nonspreading colonies on soft agar, but spreading dendritic colonies on soft agar containing glucose. In the presence of glucose, an initial cell growth-dependent phase was followed by a secondary SprB-independent, gliding motility-dependent phase. The branching pattern of a ΔsprB colony was less complex than the pattern formed by the WT. Mesoscopic and microstructural information was obtained by atmospheric scanning electron microscopy (ASEM) and transmission EM, respectively. In the growth-dependent phase of WT colonies, dendritic tips spread rapidly by the movement of individual cells. In the following SprB-independent phase, leading tips were extended outwards by the movement of dynamic windmill-like rolling centers, and the lipoproteins were expressed more abundantly. Dark spots in WT cells during the growth-dependent spreading phase were not observed in the SprB-independent phase. Various mutations showed that the lipoproteins and the motility machinery were necessary for SprB-independent spreading. Overall, SprB-independent colony spreading is influenced by the lipoproteins, some of which are involved in the gliding machinery, and medium conditions, which together determine the nutrient-seeking behavior.

Effect of food preservatives on in situ biofilm formation

2008 ◽  
Vol 12 (3) ◽  
pp. 203-208 ◽  
Author(s):  
Nicole Birgit Arweiler ◽  
Ronaldo Lenz ◽  
Anton Sculean ◽  
Ali Al-Ahmad ◽  
Elmar Hellwig ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Food Preservatives ◽  
Effect Of Food

scholarly journals Oxygen tension during biofilm growth influences the efficacy antimicrobial agents

2016 ◽  
Vol 45 (5) ◽  
pp. 302-307 ◽  
Author(s):  
Raquel Pippi ANTONIAZZI ◽  
Gabriela Ocampo TROJAHN ◽  
Maísa CASARIN ◽  
Camilla Filippi dos Santos ALVES ◽  
Roberto Christ Vianna SANTOS ◽  
...  
Keyword(s):  
Green Tea ◽  
Oxygen Tension ◽  
Biofilm Formation ◽  
Antimicrobial Agents ◽  
Dental Students ◽  
Low Oxygen ◽  
Biofilm Growth ◽  
Model Method ◽  
Colony Forming Units

Abstract Objective To compare the antimicrobial efficacy of a 0.12% chlorhexidine (CHX) and herbal green tea (Camellia sinensis) solution on established biofilms formed at different oxygen tensions in an in situ model. Method Twenty-five dental students were eligible for the study. In situ devices with standardized enamel specimens (ES) facing the palatal and buccal sides were inserted in the mouths of volunteers for a 7 day period. No agent was applied during the first four days. From the fifth day onward, both agents were applied to the test ES group and no agent was applied to the control ES group. After 7 days the ES fragments were removed from the devices, sonicated, plated on agar, and incubated for 24 h at 37 °C to determine and quantify the colony forming units (CFUs). Result CHX had significantly higher efficacy compared to green tea on the buccal (1330 vs. 2170 CFU/µL) and palatal (2250 vs. 2520 CFU/µL) ES. In addition, intragroup comparisons showed significantly higher efficacy in buccal ES over palatal ES (1330 vs. 2250 CFU/µL for CHX and 2170 vs, 2520 CFU/µL for CV) for both solutions. Analysis of the ES controls showed significantly higher biofilm formation in palatal ES compared to buccal ES. Conclusion CHX has higher efficacy than green tea on 4-day biofilms. The efficacy of both agents was reduced for biofilms grown in a low oxygen tension environment. Therefore, the oxygen tension environment seems to influence the efficacy of the tested agents.

scholarly journals Effects of Baseplates of Orthodontic Appliances with in situ generated Silver Nanoparticles on Cariogenic Bacteria: A Randomized, Doubleblind Cross-over Clinical Trial

2015 ◽  
Vol 16 (4) ◽  
pp. 291-298 ◽  
Author(s):  
Roghayeh Ghorbanzadeh ◽  
Babak Pourakbari
Keyword(s):  
Clinical Trial ◽  
Silver Nanoparticles ◽  
Biofilm Formation ◽  
Orthodontic Appliances ◽  
Bacterial Cells ◽  
Streptococcus Sobrinus ◽  
Double Blind ◽  
Biofilm Inhibition ◽  
Cariogenic Bacteria

ABSTRACT Aim Polymethyl-methacrylate (PMMA) is commonly used primarily for baseplates of orthodontic appliances (BOA). The activities of cariogenic bacteria in biofilm on these surfaces may contribute to dental caries, gingival inflammation and periodontal disease. The PMMA incorporated with nanoparticles of silver (NanoAg-I-PMMA) and NanoAg in situ in PMMA (NanoAg-IS-PMMA) have been shown to control the growth of cariogenic bacteria, but clinical trial of anti-cariogenic application of these novel materials in orthodontics has not been evaluated. The main aim of the study is to compare the clinical effectiveness of using NanoAg-IS-PMMA and NanoAg-I-PMMA for construction of new BOA in inhibiting the planktonic growth and biofilm formation of the cariogenic bacteria. Materials and methods Twenty four patients with a median age of 12.6 years (7-15) harboring Streptococcus mutans, Streptococcus sobrinus and Lactobacillus acidophilus as well as Lactobacillus casei participated in the randomized, doubleblind, cross-over study. The experimental BOA, NanoAg-ISBOA and NanoAg-I-BOA, contained 0.5% w/w NanoAg while the control BOA was standard PMMA. Antibacterial effect of NanoAg-IS-BOA and NanoAg-I-BOA was assessed against test cariogenic bacteria by planktonic and biofilm bacterial cells growth inhibition. Results The average levels of test cariogenic bacteria in saliva decreased about 2 to 70 fold (30.9-98.4%) compared to baseline depending on the microorganism type and test BOA. Biofilm inhibition analysis demonstrated that NanoAg-I-BOA and NanoAg-IS-BOA inhibited the biofilm of all test bacteria by 20.1 to 79.9% compared to BOA. NanoAg-IS-BOA had a strong anti-biofilm effect against S. mutans, S. sobrinus and L. casei. However, NanoAg-I-BOA showed only slight antibiofilm effects on test bacteria. Most notably, at all period of the clinical trial, NanoAg-IS-BOA showed a higher antibacterial activity than NanoAg-I-BOA. Conclusion Based on the novel data that presented here, the NanoAg-IS-BOA had strong antimicrobial activity in the planktonic phase and subsequent biofilm formation of the cariogenic bacteria. Clinical significance Wearing of NanoAg-IS-BOA has the potential to minimize dental plaque formation and caries during orthodontic treatment. How to cite this article Ghorbanzadeh R, Pourakbari B, Bahador A. Effects of Baseplates of Orthodontic Appliances with in situ generated Silver Nanoparticles on Cariogenic Bacteria: A Randomized, Double-blind Cross-over Clinical Trial. J Contemp Dent Pract 2015;16(4):291-298.

scholarly journals In-situ monitoring AHL-mediated quorum-sensing regulation of the initial phase of wastewater biofilm formation

2020 ◽  
Vol 135 ◽  
pp. 105326 ◽  
Author(s):  
Jinfeng Wang ◽  
Qiuju Liu ◽  
Xianhui Li ◽  
Sijia Ma ◽  
Haidong Hu ◽  
...  
Keyword(s):  
Quorum Sensing ◽  
Biofilm Formation ◽  
Initial Phase ◽  
In Situ Monitoring

scholarly journals A microfluidic platform for in situ investigation of biofilm formation and its treatment under controlled conditions

2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Hervé Straub ◽  
Leo Eberl ◽  
Manfred Zinn ◽  
René M. Rossi ◽  
Katharina Maniura-Weber ◽  
...  
Keyword(s):  
Single Cell ◽  
Real Time ◽  
Bacterial Adhesion ◽  
Biofilm Formation ◽  
Bacterial Colonization ◽  
Rich Medium ◽  
Flow Conditions ◽  
Microfluidic Platform ◽  
Adhesion Rate

Abstract Background Studying bacterial adhesion and early biofilm development is crucial for understanding the physiology of sessile bacteria and forms the basis for the development of novel antimicrobial biomaterials. Microfluidics technologies can be applied in such studies since they permit dynamic real-time analysis and a more precise control of relevant parameters compared to traditional static and flow chamber assays. In this work, we aimed to establish a microfluidic platform that permits real-time observation of bacterial adhesion and biofilm formation under precisely controlled homogeneous laminar flow conditions. Results Using Escherichia coli as the model bacterial strain, a microfluidic platform was developed to overcome several limitations of conventional microfluidics such as the lack of spatial control over bacterial colonization and allow label-free observation of bacterial proliferation at single-cell resolution. This platform was applied to demonstrate the influence of culture media on bacterial colonization and the consequent eradication of sessile bacteria by antibiotic. As expected, the nutrient-poor medium (modified M9 minimal medium) was found to promote bacterial adhesion and to enable a higher adhesion rate compared to the nutrient-rich medium (tryptic soy broth rich medium ). However, in rich medium the adhered cells colonized the glass surface faster than those in poor medium under otherwise identical conditions. For the first time, this effect was demonstrated to be caused by a higher retention of newly generated bacteria in the rich medium, rather than faster growth especially during the initial adhesion phase. These results also indicate that higher adhesion rate does not necessarily lead to faster biofilm formation. Antibiotic treatment of sessile bacteria with colistin was further monitored by fluorescence microscopy at single-cell resolution, allowing in situ analysis of killing efficacy of antimicrobials. Conclusion The platform established here represents a powerful and versatile tool for studying environmental effects such as medium composition on bacterial adhesion and biofilm formation. Our microfluidic setup shows great potential for the in vitro assessment of new antimicrobials and antifouling agents under flow conditions.

Materials Sealing Preventing Biofilm Formation in Implant/Abutment Joints: Which Is the Most Effective? A Systematic Review and Meta-Analysis

2020 ◽  
Vol 46 (2) ◽  
pp. 163-171
Author(s):  
Cecília Alves de Sousa ◽  
Maria Beatriz Bello Taborda ◽  
Gustavo Antônio Correa Momesso ◽  
Eduardo Passos Rocha ◽  
Paulo Henrique dos Santos ◽  
...  
Keyword(s):  
Systematic Review ◽  
Biofilm Formation ◽  
Meta Analysis ◽  
Significance Level ◽  
Gutta Percha ◽  
Significant Difference ◽  
Physical Barriers ◽  
External Connection

The purpose of this systematic review was to evaluate the literature available for materials exhibiting the best efficacy in preventing biofilm formation in the interior of implants. We searched PubMed/MEDLINE, Scopus, and Cochrane databases. This review is registered with the PROSPERO database and followed the suitability of the PRISMA protocol. The initial search resulted in 326 articles from the databases. After they were read, 8 articles remained, and the inclusion and exclusion criteria were applied. Six of these 8 articles were classified as in vitro and 2 were classified as in situ. The regions of the implants evaluated ranged from the interface of the pieces to the occlusal upper access of the abutment. The implant connections evaluated the Morse taper, external connection, and internal connection. Meta-analysis of the quantitative data was performed at a significance level of .05. Cotton exhibited poor control of infiltration, even in combination with other materials. Isolated gutta-percha (GP) and polytetrafluoroethylene (PTFE) tape with composite resin (CR) or GP performed better as physical barriers. The best results for chemical barriers were observed by the application of 1% chlorhexidine gluconate (CG) gel, thymol varnish, and the deposition of Ag films onto the surface. The applied meta-analysis did not show a significant difference in comparison between the different types of implant connections (P > .05). The application of CG and thymol varnish antimicrobials was effective in preventing biofilm formation and easy clinical execution; these could be used in combination with CR, GP, and PTFE.

scholarly journals Effects of Experimental Agents Containing Tannic Acid or Chitosan on the Bacterial Biofilm Formation in Situ

Biomolecules ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1315
Author(s):  
Anton Schestakow ◽  
Matthias Hannig
Keyword(s):  
Hydrochloric Acid ◽  
Tannic Acid ◽  
Biofilm Formation ◽  
Antibacterial Properties ◽  
Positive Control ◽  
Bacterial Biofilm ◽  
Dental Biofilm ◽  
Acid Ph ◽  
Bovine Enamel

Chitosan and tannic acid are known for their antibacterial properties. In the present in-situ study, their antibacterial and anti-adherent effects on biofilm formation on enamel were investigated. Six subjects carried upper jaw splints with bovine enamel specimens, allowing in-situ biofilm formation. During the two-day trial, subjects rinsed with experimental solutions that contained either chitosan, tannic acid (pH = 2.5), tannic acid (pH = 7) or hydrochloric acid. Water served as the negative and chlorhexidine as the positive control. Rinsing occurred four or five times following two different rinsing protocols to investigate both the immediate and long-lasting effects. After 48 h of intraoral exposure, the dental plaque was stained with LIVE/DEAD® BacLight, and fluorescence micrographs were evaluated by using the software ImageJ. The results were verified by scanning electron microscopy. Rinsing with chitosan resulted in little immediate antibacterial and anti-adherent effects but failed to show any long-lasting effect, while rinsing with tannic acid resulted in strong immediate and long-lasting effects. Except for a slightly lower antibacterial effect, the neutral solution of tannic acid was as good as the acidic solution. Hydrochloric acid showed neither an antibacterial nor an anti-adherent effect on dental biofilm formation. Experimental solutions containing tannic acid are promising anti-biofilm agents, irrespective of the pH values of the solutions. Chitosan, on the other hand, was not able to prevent biofilm formation.

Sign in / Sign up

Export Citation Format

Share Document