scholarly journals Influence of Selected Factors on Biofilm Formation by Salmonella enterica Strains

2020 ◽  
Vol 9 (1) ◽  
pp. 43
Author(s):  
Agata Białucha ◽  
Eugenia Gospodarek-Komkowska ◽  
Joanna Kwiecińska-Piróg ◽  
Krzysztof Skowron
Keyword(s):  
Salmonella Enterica ◽  
Biofilm Formation ◽  
Chronic Infection ◽  
Clinical Strains ◽  
Nutritional Conditions ◽  
Bovine Bile

Biofilm formed by S. enterica on the surface of gallstones or biomaterials promotes the development and spread of chronic infection. The aim of the study was to assess biofilm formation on the surface of polystyrene depending on nutritional conditions and the effect of 0.5, 1.0, and 2.0% glucose and 3.0% bile and sub-inhibitory concentrations of ampicillin on biofilm formation of S. enterica. Sixty-nine clinical strains of S. enterica isolated from feces (92.8%) and blood (7.2%) collected from patients (66.7%) and carriers (33.3%) were used in the study. Assessment of forming 24-h biofilm by these strains was performed on the surface of polystyrene 96-well plates at 37 °C. In this study, it was indicated that 1.0% glucose and 3.0% bovine bile inhibit biofilm formation. Biofilm formation was inhibited in all examined sub-MIC of ampicillin. Biofilm formation is varied in different conditions, depending on the serovar.

scholarly journals CD25890, a conserved protein that modulates sporulation initiation in Clostridioides difficile

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Diogo Martins ◽  
Michael A. DiCandia ◽  
Aristides L. Mendes ◽  
Daniela Wetzel ◽  
Shonna M. McBride ◽  
...  
Keyword(s):  
Life Cycle ◽  
Biofilm Formation ◽  
Regulatory Protein ◽  
Well Being ◽  
Human Intestine ◽  
Healthy Humans ◽  
Clostridioides Difficile ◽  
Nutritional Conditions ◽  
Sporulation Initiation

AbstractBacteria that reside in the gastrointestinal tract of healthy humans are essential for our health, sustenance and well-being. About 50–60% of those bacteria have the ability to produce resilient spores that are important for the life cycle in the gut and for host-to-host transmission. A genomic signature for sporulation in the human intestine was recently described, which spans both commensals and pathogens such as Clostridioides difficile and contains several genes of unknown function. We report on the characterization of a signature gene, CD25890, which, as we show is involved in the control of sporulation initiation in C. difficile under certain nutritional conditions. Spo0A is the main regulatory protein controlling entry into sporulation and we show that an in-frame deletion of CD25890 results in increased expression of spo0A per cell and increased sporulation. The effect of CD25890 on spo0A is likely indirect and mediated through repression of the sinRR´ operon. Deletion of the CD25890 gene, however, does not alter the expression of the genes coding for the cytotoxins or the genes involved in biofilm formation. Our results suggest that CD25890 acts to modulate sporulation in response to the nutrients present in the environment.

Influence of milk, chicken residues and oxygen levels on biofilm formation on stainless steel, gene expression and small RNAs in Salmonella enterica

Food Control ◽  
2018 ◽  
Vol 90 ◽  
pp. 1-9 ◽  
Author(s):  
Alexandre Lamas ◽  
Patricia Regal ◽  
Beatriz Vázquez ◽  
José Manuel Miranda ◽  
Alberto Cepeda ◽  
...  
Keyword(s):  
Gene Expression ◽  
Stainless Steel ◽  
Salmonella Enterica ◽  
Biofilm Formation ◽  
Small Rnas ◽  
Oxygen Levels

scholarly journals Studying of biofilm formation by clinical strains of Candida albicans in interaction with Fusarium solani to predict the severity of atopic dermatitis

2020 ◽  
Vol 101 (3) ◽  
pp. 337-341
Author(s):  
S A Lisovskaya ◽  
R I Valieva ◽  
A A Sharifullina ◽  
E V Fayzullina ◽  
I M Khismatullina ◽  
...  
Keyword(s):  
Atopic Dermatitis ◽  
Candida Albicans ◽  
Fusarium Solani ◽  
Biofilm Formation ◽  
Film Formation ◽  
Disease Process ◽  
Skin Infections ◽  
Clinical Strains ◽  
Plate Reader ◽  
Fungus Extract

Aim. To assess the ability to form biofilms by clinical strains of the yeast Candida albicans isolated from patients with atopic dermatitis in exacerbation and remission stages under the effect of Fusarium solani micromycete and its absence. Methods. The study included 70 strains of C. albicans and one strain of F. solani. Fungal biofilms formed according to the method of Ramage. The optical density of the biofilms measured using a micro plate reader at 620 nm. The effect of associated fungi on the biofilm-forming properties of C. albicans strains was studied by an extract from opportunistic F. solani fungi. Results. The greatest biofilm formation was observed in strains isolated at the remission stage. The strains isolated in the acute period were inferior to them in the ability to form biofilms (average values of film formation were 0.143 and 0.087, respectively). Co-cultivation of C. albicans strains with F. solani fungus extract stimulated biofilm formation of C. albicans strains at a concentration of 1:10. Conclusion. This study showed a possible synergism between C. albicans and F. solani in polymicrobial skin infections, because the products of the fungus F. solani increase one of the virulence factors of the fungus C. albicans; the possibility to assess of a stimulating effect of associated fungi on the virulence one of an agent of infectious disease process will allow predicting the disease severity.

scholarly journals Inhibitory effect of propafenone derivatives on pseudomonas aeruginosa biofilm and pyocyanin production

2020 ◽  
Vol 148 (3-4) ◽  
pp. 196-202
Author(s):  
Snjezana Petrovic ◽  
Jasmina Basic ◽  
Zoran Mandinic ◽  
Dragana Bozic ◽  
Marina Milenkovic ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Biofilm Formation ◽  
Laboratory Strain ◽  
Inhibitory Effect ◽  
Negative Control ◽  
Clinical Strains ◽  
Control Value ◽  
Essential Components ◽  
Pyocyanin Production

Introduction/Objective. Biofilm and pyocyanin production are essential components of Pseudomonas aeruginosa virulence and antibiotic resistance. Our objective was to examine inhibitory effect of synthetized propafenone derivatives 3-(2-Fluorophenyl)- 1-(2- (2-hydroxy-3-propylamino-propoxy)-phenyl)-propan-1-one hydrochloride (5OF) and3-(2- Trifluoromethyl-phenyl)-1-(2-(2-hydroxy-3-propylamino-propoxy)-phenyl)-propan-1-one hydrochloride (5CF3) on biofilm and pyocyanin in Pseudomonas aeruginosa clinical strains. Methods. Effects were tested on nine clinical isolates and one control laboratory strain of P. aeruginosa. In vitro analysis of biofilm growing was performed by incubating bacteria (0.5 McFarland) with 5OF and 5CF3 (500?31.2 ?g/ml) and measuring optical density (OD) at 570 nm. Bacteria in medium without compounds were positive control. Blank medium (an uninoculated medium without test compounds) was used as negative control. Pyocyanin production was estimated by OD at 520 nm, after bacteria incubated with 5CF3 and 5OF (250 and 500 ?g/ml), treated with chloroform, and chloroform layer mixed with HCl. Results. A total of 500 ?g/ml of 5OF and 5CF3 completely inhibited biofilm formation in 10/10 and 4/10 strains, respectively. A total of 250 ?g/ml of 5OF and 5CF3 strongly inhibited biofilm formation in 7/10 strains, while inhibition with 125 ?g/ml of 5OF and 5CF3 was moderate. Lower concentrations had almost no effect on biofilm production. Pyocyanin production was reduced to less than 40% of the control value in 6/9, and less than 50% of the control in 7/9 strains with 500 ?g/ml of 5OF and 5CF3, respectively. At 250 ?g/ml 5OF and 5CF3, most strains had pyocyanin production above 50% of the control value. Conclusion. Synthetized propafenone derivatives, 5OF and 5CF3, inhibited biofilms and pyocyanin production of Pseudomonas aeruginosa clinical strains. Presented results suggest that propafenone derivatives are potential lead-compounds for synthesis of novel antipseudomonal drugs.

Characterization of biofilm formation by Salmonella enterica at the air-liquid interface in aquatic environments

2018 ◽  
Vol 190 (4) ◽  
Author(s):  
José Andrés Medrano-Félix ◽  
Cristóbal Chaidez ◽  
Kristina D. Mena ◽  
María del Socorro Soto-Galindo ◽  
Nohelia Castro-del Campo
Keyword(s):  
Salmonella Enterica ◽  
Biofilm Formation ◽  
Liquid Interface ◽  
Aquatic Environments ◽  
Air Liquid Interface

Endotracheal tubes coated with a broad-spectrum antibacterial ceragenin reduce bacterial biofilm in an in vitro bench top model

2021 ◽  
Author(s):  
María Consuelo Latorre ◽  
María Jesús Pérez-Granda ◽  
Paul B Savage ◽  
Beatriz Alonso ◽  
Pablo Martín-Rabadán ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Laser Scanning ◽  
In Vitro Study ◽  
Bacterial Biofilm ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Endotracheal Tubes ◽  
Clinical Strains ◽  
Number Of Cells

Abstract Background Ventilator-associated pneumonia is one of the most common nosocomial infections, caused mainly by bacterial/fungal biofilm. Therefore, it is necessary to develop preventive strategies to avoid biofilm formation based on new compounds. Objectives We performed an in vitro study to compare the efficacy of endotracheal tubes (ETTs) coated with the ceragenin CSA-131 and that of uncoated ETTs against the biofilm of clinical strains of Pseudomonas aeruginosa (PA), Escherichia coli (EC) and Staphylococcus aureus (SA). Methods We applied an in vitro bench top model using coated and uncoated ETTs that were treated with three different clinical strains of PA, EC and SA for 5 days. After exposure to biofilm, ETTs were analysed for cfu count by culture of sonicate and total number of cells by confocal laser scanning microscopy. Results The median (IQR) cfu/mL counts of PA, EC and SA in coated and uncoated ETTs were, respectively, as follows: 1.00 × 101 (0.0–3.3 × 102) versus 3.32 × 109 (6.6 × 108–3.8 × 109), P < 0.001; 0.0 (0.0–5.4 × 103) versus 1.32 × 106 (2.3 × 103–5.0 × 107), P < 0.001; and 8.1 × 105 (8.5 × 101–1.4 × 109) versus 2.7 × 108 (8.6 × 106–1.6 × 1011), P = 0.058. The median (IQR) total number of cells of PA, EC and SA in coated and non-coated ETTs were, respectively, as follows: 11.0 [5.5–not applicable (NA)] versus 87.9 (60.5–NA), P = 0.05; 9.1 (6.7–NA) versus 62.6 (42.0–NA), P = 0.05; and 97.7 (94.6–NA) versus 187.3 (43.9–NA), P = 0.827. Conclusions We demonstrated significantly reduced biofilm formation in coated ETTs. However, the difference for SA was not statistically significant. Future clinical studies are needed to support our findings.

scholarly journals Biofilms in Diabetic Foot Ulcers: Significance and Clinical Relevance

2020 ◽  
Vol 8 (10) ◽  
pp. 1580
Author(s):  
Cassandra Pouget ◽  
Catherine Dunyach-Remy ◽  
Alix Pantel ◽  
Sophie Schuldiner ◽  
Albert Sotto ◽  
...  
Keyword(s):  
Diabetic Foot ◽  
Biofilm Formation ◽  
Chronic Infection ◽  
Current Knowledge ◽  
Bacterial Species ◽  
Limb Amputation ◽  
Foot Ulcers ◽  
Main Role ◽  
Diabetic Foot Ulcers ◽  
Patients With Diabetes

Foot infections are the main disabling complication in patients with diabetes mellitus. These infections can lead to lower-limb amputation, increasing mortality and decreasing the quality of life. Biofilm formation is an important pathophysiology step in diabetic foot ulcers (DFU)—it plays a main role in the disease progression and chronicity of the lesion, the development of antibiotic resistance, and makes wound healing difficult to treat. The main problem is the difficulty in distinguishing between infection and colonization in DFU. The bacteria present in DFU are organized into functionally equivalent pathogroups that allow for close interactions between the bacteria within the biofilm. Consequently, some bacterial species that alone would be considered non-pathogenic, or incapable of maintaining a chronic infection, could co-aggregate symbiotically in a pathogenic biofilm and act synergistically to cause a chronic infection. In this review, we discuss current knowledge on biofilm formation, its presence in DFU, how the diabetic environment affects biofilm formation and its regulation, and the clinical implications.

Sign in / Sign up

Export Citation Format

Share Document