Evaluation of biofilm formation, cell surface hydrophobicity and gelatinase activity in Acinetobacter baumannii strains isolated from patients of diabetic and non-diabetic foot ulcer infections

Objective: The aim of the study was to assess and compare the gelatinase activity and pellicle formation in extended-spectrum beta-lactamase (ESBL) and non-ESBL producing Acinetobacter baumannii isolates from diabetic foot ulcer infection (DFI).Methods: A total of 42 isolates of A. baumannii recovered from patients of DFI from September 2016 to February 2018. Isolates were identified by the standard microbiological method and confirmed by the BD Phoenix 100 system. The antimicrobial susceptibility test was performed by the Kirby–Bauer disk diffusion method and ESBL was detected by double disk diffusion synergy test method. Gelatinase production was determined by the Luria Bertani agar supplemented with 30 g/L gelatin, and pellicle formation was determined by the Mueller-Hinton broth which is incubated at two different temperatures.Results: A total of 42 A. baumannii isolates were multidrug resistant. Among 21 isolates, each was ESBL and non-ESBL producers. Pellicle formation at 25°C in ESBL and non-ESBL producer isolates was 47.61% (10/21) and 28.57% (06/21). Pellicle formation at 37°C in ESBL and non-ESBL producer isolates was 57.14% (12/21) and 42.85% (09/21), respectively. Gelatinase production was present in 38.09% ESBL and 28.57% in non-ESBL producers. ESBL strains were more virulent compared to non-ESBL producers among patients of DFIs.Conclusion: This study showed that pellicle formation at 37°C was highly virulent due to ESBL producers. Gelatinase production was elevated in ESBL compared to non-ESBL producer isolates. This attribute of the isolates could render ESBL positive more pathogenic. Colistin and polymyxin B are the only choices of treatment for multidrug-resistant Acinetobacter baumannii infections.

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Quercetin inhibits virulence properties of Porphyromas gingivalis in periodontal disease

Scientific Reports ◽

10.1038/s41598-020-74977-y ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Zhiyan He ◽

Xu Zhang ◽

Zhongchen Song ◽

Lu Li ◽

Haishuang Chang ◽

...

Keyword(s):

Cell Surface ◽

Periodontal Disease ◽

Biofilm Formation ◽

Cell Structure ◽

Cell Surface Hydrophobicity ◽

Surface Hydrophobicity ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Antimicrobial Effects ◽

Virulence Properties

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.

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Effect of Eugenol on Cell Surface Hydrophobicity, Adhesion, and Biofilm ofCandida tropicalisandCandida dubliniensisIsolated from Oral Cavity of HIV-Infected Patients

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2014/505204 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 20

Author(s):

Suelen Balero de Paula ◽

Thais Fernanda Bartelli ◽

Vanessa Di Raimo ◽

Jussevania Pereira Santos ◽

Alexandre Tadachi Morey ◽

...

Keyword(s):

Cell Surface ◽

Oral Cavity ◽

Biofilm Formation ◽

Cell Surface Hydrophobicity ◽

Surface Hydrophobicity ◽

Planktonic Cells ◽

Hydrophobic Behavior ◽

Significant Difference ◽

Substrate Surfaces ◽

Sessile Cells

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.

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Factors associated with adherence to and biofilm formation on polystyrene byStenotrophomonas maltophilia: the role of cell surface hydrophobicity and motility

FEMS Microbiology Letters ◽

10.1111/j.1574-6968.2008.01292.x ◽

2008 ◽

Vol 287 (1) ◽

pp. 41-47 ◽

Cited By ~ 94

Author(s):

Arianna Pompilio ◽

Raffaele Piccolomini ◽

Carla Picciani ◽

Domenico D'Antonio ◽

Vincenzo Savini ◽

...

Keyword(s):

Cell Surface ◽

Biofilm Formation ◽

Cell Surface Hydrophobicity ◽

Surface Hydrophobicity ◽

Factors Associated

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Spectrum of bacteria associated with diabetic foot ulcer and biofilm formation: A prospective study

Australasian Medical Journal ◽

10.4066/amj.2015.2422 ◽

2015 ◽

pp. 280-285 ◽

Cited By ~ 33

Author(s):

Asima Banu ◽

Mir Mohammad Noorul Hassan ◽

Janani Rajkumar ◽

Sathyabheemarao Srinivasa

Keyword(s):

Prospective Study ◽

Diabetic Foot ◽

Biofilm Formation ◽

Foot Ulcer ◽

Diabetic Foot Ulcer ◽

A Prospective Study

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Biofilm Formation and Cell Surface Properties among Pathogenic and Nonpathogenic Strains of the Bacillus cereus Group

Applied and Environmental Microbiology ◽

10.1128/aem.00155-09 ◽

2009 ◽

Vol 75 (20) ◽

pp. 6616-6618 ◽

Cited By ~ 81

Author(s):

Sandrine Auger ◽

Nalini Ramarao ◽

Christine Faille ◽

Agnès Fouet ◽

Stéphane Aymerich ◽

...

Keyword(s):

Epithelial Cells ◽

Cell Surface ◽

Bacillus Cereus ◽

Digestive Tract ◽

Biofilm Formation ◽

Cell Surface Hydrophobicity ◽

Surface Hydrophobicity ◽

Bacillus Cereus Group ◽

Cell Surface Properties ◽

Tract Infections

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.

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