SubMICs of penicillin and erythromycin enhance biofilm formation and hydrophobicity of Corynebacterium diphtheriae strains

2013 ◽  
Vol 62 (5) ◽  
pp. 754-760 ◽  
Author(s):  
D. L. R. Gomes ◽  
R. S. Peixoto ◽  
E. A. B. Barbosa ◽  
F. Napoleão ◽  
P. S. Sabbadini ◽  
...  

Subinhibitory concentrations (subMICs) of antibiotics may alter bacterial surface properties and change microbial physiology. This study aimed to investigate the effect of a subMIC (⅛ MIC) of penicillin (PEN) and erythromycin (ERY) on bacterial morphology, haemagglutinating activity, cell-surface hydrophobicity (CSH) and biofilm formation on glass and polystyrene surfaces, as well as the distribution of cell-surface acidic anionic residues of Corynebacterium diphtheriae strains (HC01 tox − strain; CDC-E8392 and 241 tox + strains). All micro-organisms tested were susceptible to PEN and ERY. Growth in the presence of PEN induced bacterial filamentation, whereas subMIC of ERY caused cell-size reduction of strains 241 and CDC-E8392. Adherence to human erythrocytes was reduced after growth in the presence of ERY, while CSH was increased by a subMIC of both antibiotics in bacterial adherence to n-hexadecane assays. Conversely, antibiotic inhibition of biofilm formation was not observed. All strains enhanced biofilm formation on glass after treatment with ERY, while only strain 241 increased glass adherence after cultivation in the presence of PEN. Biofilm production on polystyrene surfaces was improved by ⅛ MIC of ERY. After growth in the presence of both antimicrobial agents, strains 241 and CDC-E8392 exhibited anionic surface charges with focal distribution. In conclusion, subMICs of PEN and ERY modified bacterial surface properties and enhanced not only biofilm formation but also cell-surface hydrophobicity. Antibiotic-induced biofilm formation may contribute to the inconsistent success of antimicrobial therapy for C. diphtheriae infections.

2018 ◽  
Author(s):  
Manash C. Das ◽  
Antu Das ◽  
Sourabh Samaddar ◽  
Akshay Vishnu Daware ◽  
Chinmoy Ghosh ◽  
...  

AbstractBacterial surface hydrophobicity is one of the determinant biophysical parameters of bacterial aggregation for being networked to form biofilm. Phytoconstituents like vitexin have long been in use for their antibacterial effect. The present work is aimed to characterise the effect of vitexin onS. aureussurface hydrophobicity and corresponding aggregation to form biofilm. We have found that vitexin shows minimum inhibitory concentration at 252 μg/ml againstS. aureus.Vitexin reduces cell surface hydrophobicity and membrane permeability at sub-MIC dose of 126 μg/ml. Thein silicobinding analysis showed higher binding affinity of vitexin with surface proteins ofS. aureus.Down regulation ofdltA,icaAB and reduction in membrane potential under sub-MIC dose of vitexin, explains reducedS. aureussurface hydrophobicity. Vitexin has substantially reduced the intracellular adhesion of planktonic cells to form biofilm through interference of EPS formation, motility and subsequent execution of virulence. This was supported by the observation that vitexin down regulates the expression oficaAB andagrAC genes ofS. aureus.In addition, vitexin also found to potentiate antibiofilm activity of sub-MIC dose of gentamicin and azithromycin. Furthermore, CFU count, histological examination of mouse tissue and immunomodulatory study justifies thein vivoprotective effect of vitexin fromS. aureusbiofilm associated infection. Finally it can be inferred that, vitexin has the ability to modulateS. aureuscell surface hydrophobicity which can further interfere biofilm formation of the bacteria.ImportanceThere has been substantial information known about role of bacterial surface hydrophobicity during attachment of single planktonic bacterial cells to any surface and the subsequent development of mature biofilm. This study presents the effect of flavone phytoconstituent vitexin on modulation of cell surface hydrophobicity in reducing formation of biofilm. Our findings also highlight the ability of vitexin in reducingin vivo S. aureusbiofilm which will eventually outcompete the correspondingin vitroantibiofilm effect. Synergistic effect of vitexin on azithromycin and gentamicin point to a regime where development of drug tolerance may be addressed. Our findings explore one probable way of overcoming drug tolerance through application of vitexin in addressing the issue ofS. aureusbiofilm through modulation of cell surface hydrophobicity.


2021 ◽  
Vol 8 (4) ◽  
pp. 263-267
Author(s):  
Anandkumar H ◽  
Amaresh Nigudgi ◽  
Vinay Hajare ◽  
Sunil Biradar

The attachment of the bacteria to the host cell and ability to invade the cell are regarded as important steps in the infectious process. The hydrophobicity of the microbial surface plays a critical role in the adherence of bacteria to the surface. The ability of biofilm formation can increase survival chance of microorganism, as cell growing in biofilm are highly resistant to the components of the immune system and many antimicrobial agents. Infection caused by ESBL- producers are associated with severe adverse outcomes and may be related to increased virulence of these strains.: A total of 100 urinary were selected for the study, of which 50 strains were from ESBL producers and 50 from non- ESBL-producing uropathogenic(UPEC) strains. The urinary isolates that were resistant to at least one of the three indicator cephalosporins (cefotaxime, cefpodoxime and ceftazidime) were tested for ESBL production by quantitative E-strip method. All the 100 urinary strains were tested for cell surface hydrophobicity (CSH) by salt aggregation method and Biofilm production by tissue culture plate method.Among ESBL producers, 19 (38%) were CSH positive and 34 (68%) were biofilm producers. However among non-ESBL producers, 05 (10%) were CSH positive and 12 (24%) were biofilm producers. Statistically significant difference (<0.001) was seen in the occurrence of CSH and biofilm production between ESBL and non ESBL producing UPEC isolates.In the present study, it was found that the ESBL producing isolates had a higher ability to form biofilm and CSH; both of them are among the important virulence factors associated with cell surface adherence which is the first step in bacterial infection.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Zhiyan He ◽  
Xu Zhang ◽  
Zhongchen Song ◽  
Lu Li ◽  
Haishuang Chang ◽  
...  

Abstract Porphyromonas gingivalis is a causative agent in the onset and progression of periodontal disease. This study aims to investigate the effects of quercetin, a natural plant product, on P. gingivalis virulence properties including gingipain, haemagglutinin and biofilm formation. Antimicrobial effects and morphological changes of quercetin on P. gingivalis were detected. The effects of quercetin on gingipains activities and hemolytic, hemagglutination activities were evaluated using chromogenic peptides and sheep erythrocytes. The biofilm biomass and metabolism with different concentrations of quercetin were assessed by the crystal violet and MTT assay. The structures and thickness of the biofilms were observed by confocal laser scanning microscopy. Bacterial cell surface properties including cell surface hydrophobicity and aggregation were also evaluated. The mRNA expression of virulence and iron/heme utilization was assessed using real time-PCR. Quercetin exhibited antimicrobial effects and damaged the cell structure. Quercetin can inhibit gingipains, hemolytic, hemagglutination activities and biofilm formation at sub-MIC concentrations. Molecular docking analysis further indicated that quercetin can interact with gingipains. The biofilm became sparser and thinner after quercetin treatment. Quercetin also modulate cell surface hydrophobicity and aggregation. Expression of the genes tested was down-regulated in the presence of quercetin. In conclusion, our study demonstrated that quercetin inhibited various virulence factors of P. gingivalis.


1999 ◽  
Vol 38 (1) ◽  
pp. 37-42 ◽  
Author(s):  
Ana Luiza Mattos-Guaraldi ◽  
Luiz Carlos Duarte Formiga ◽  
Arnaldo Feitosa Braga Andrade

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Suelen Balero de Paula ◽  
Thais Fernanda Bartelli ◽  
Vanessa Di Raimo ◽  
Jussevania Pereira Santos ◽  
Alexandre Tadachi Morey ◽  
...  

MostCandidaspp. infections are associated with biofilm formation on host surfaces. Cells within these communities display a phenotype resistant to antimicrobials and host defenses, so biofilm-associated infections are difficult to treat, representing a source of reinfections. The present study evaluated the effect of eugenol on the adherence properties and biofilm formation capacity ofCandida dubliniensisandCandida tropicalisisolated from the oral cavity of HIV-infected patients. All isolates were able to form biofilms on different substrate surfaces. Eugenol showed inhibitory activity against planktonic and sessile cells ofCandidaspp. No metabolic activity in biofilm was detected after 24 h of treatment. Scanning electron microscopy demonstrated that eugenol drastically reduced the number of sessile cells on denture material surfaces. MostCandidaspecies showed hydrophobic behavior and a significant difference in cell surface hydrophobicity was observed after exposure of planktonic cells to eugenol for 1 h. Eugenol also caused a significant reduction in adhesion of mostCandidaspp. to HEp-2 cells and to polystyrene. These findings corroborate the effectiveness of eugenol againstCandidaspecies other thanC. albicans, reinforcing its potential as an antifungal applied to limit both the growth of planktonic cells and biofilm formation on different surfaces.


2008 ◽  
Vol 287 (1) ◽  
pp. 41-47 ◽  
Author(s):  
Arianna Pompilio ◽  
Raffaele Piccolomini ◽  
Carla Picciani ◽  
Domenico D'Antonio ◽  
Vincenzo Savini ◽  
...  

2009 ◽  
Vol 75 (20) ◽  
pp. 6616-6618 ◽  
Author(s):  
Sandrine Auger ◽  
Nalini Ramarao ◽  
Christine Faille ◽  
Agnès Fouet ◽  
Stéphane Aymerich ◽  
...  

ABSTRACT Biofilm formation by 102 Bacillus cereus and B. thuringiensis strains was determined. Strains isolated from soil or involved in digestive tract infections were efficient biofilm formers, whereas strains isolated from other diseases were poor biofilm formers. Cell surface hydrophobicity, the presence of an S layer, and adhesion to epithelial cells were also examined.


Sign in / Sign up

Export Citation Format

Share Document