scholarly journals Evaluation of the Adhesive Potential of Bacteria Isolated from Meat-Related Sources

2021 ◽  
Vol 11 (22) ◽  
pp. 10652
Author(s):  
Zhenzhen Ning ◽  
Bei Xue ◽  
Huhu Wang
Keyword(s):  
Food Processing ◽  
Control Strategies ◽  
Cell Surface Hydrophobicity ◽  
Surface Hydrophobicity ◽  
Aeromonas Salmonicida ◽  
Pseudomonas Fragi ◽  
Hydrophobic Force ◽  
Aeromonas Veronii ◽  
High Level ◽  
Bacterial Hydrophobicity

Microbial adhesion constitutes the transition of microorganisms from a planktonic mode to a static one. It promotes the formation of biofilm which is responsible for spoilage, foodborne diseases, and corrosion in the food processing industry. In this study, the adhesive potential of fourteen meat-borne bacterial isolates belonging to seven different genera was investigated. All strains were found able to colonize polystyrene surfaces with different levels of firmness. Significant variations were determined in assays of bacterial hydrophobicity and motility. Among the 14 strains, Pseudomonas fragi, Aeromonas salmonicida II, Serratia liquefaciens, Citrobacter braakii, Pseudomonas putida, and Aeromonas veronii had a strong hydrophobic force, while the isolates of Lactobacillus genus showed the most hydrophilic property. In terms of motility, Citrobacter braakii and Escherichia coli exhibited exceptional swarming and swimming abilities, whilst conservatively weak performances were observed in the Lactobacillus strains. Furthermore, the majority of the isolates were predominantly electron donors and weak electron acceptors. Overall, a high level of correlation was observed between biofilm-forming ability with cell surface hydrophobicity and Lewis acid–base properties, whereas the contribution of motility in bacterial adhesion could not be confirmed. Research on the adhesive performance of foodborne bacteria is potentially conducive to developing novel control strategies, such as food processing equipment with specific surfaces, not facilitating attachment.

Activated sludge foaming: what causes hydrophobicity and can it be manipulated to control foaming?

1998 ◽  
Vol 37 (4-5) ◽  
pp. 503-509 ◽  
Author(s):  
Helen Stratton ◽  
Bob Seviour ◽  
Peter Brooks
Keyword(s):  
Activated Sludge ◽  
Control Strategies ◽  
Cell Surface Hydrophobicity ◽  
Surface Hydrophobicity ◽  
Mycolic Acid ◽  
Current Control ◽  
Operating Costs ◽  
Foam Formation ◽  
Rhodococcus Rhodochrous ◽  
Stable Foam

Activated sludge aeration tanks frequently suffer from the formation of a stable foam on their surfaces, a problem which results in increased operating costs and reduces performance. Current control strategies are often unsuccessful, mainly because of a lack of understanding of the microbes involved, and often employ expensive and environmentally undesirable procedures, such as the addition of chemicals. Here we have attempted to better understand the mechanism(s) involved in foam formation. We have investigated the possible relationship between the mycolic acid content in a Rhodococcus rhodochrous strain isolated from foam, its cell surface hydrophobicity (CSH) and ability to form stable foam. Results show that mycolic acid composition is not the only contributor to CSH, nor is the CSH the only factor responsible for foam formation and stabilisation. Other possible explanations for mechanisms of foaming and ways to control it are addressed.

scholarly journals Role ofepaQ, a Previously UncharacterizedEnterococcus faecalisGene, in Biofilm Development and Antimicrobial Resistance

2019 ◽  
Vol 201 (18) ◽  
Author(s):  
Michelle L. Korir ◽  
Jennifer L. Dale ◽  
Gary M. Dunny
Keyword(s):  
Antibiotic Resistance ◽  
Biofilm Formation ◽  
Cell Surface Hydrophobicity ◽  
Opportunistic Pathogen ◽  
Surface Hydrophobicity ◽  
Biofilm Growth ◽  
Content Type ◽  
Biofilm Architecture ◽  
High Level ◽  
Biofilm Development

ABSTRACTEnterococcus faecalisis a commensal of the human gastrointestinal tract; it is also an opportunistic pathogen and one of the leading causes of hospital-acquired infections.E. faecalisproduces biofilms that are highly resistant to antibiotics, and it has been previously reported that certain genes of theepaoperon contribute to biofilm-associated antibiotic resistance. Despite several studies examining theepaoperon, many gene products of this operon remain annotated as hypothetical proteins. Here, we further explore theepaoperon; we identifiedepaQ, currently annotated as encoding a hypothetical membrane protein, as being important for biofilm formation in the presence of the antibiotic daptomycin. Mutants with disruptions ofepaQwere more susceptible to daptomycin relative to the wild type, suggesting its importance in biofilm-associated antibiotic resistance. Furthermore, the ΔepaQmutant exhibited an altered biofilm architectural arrangement and formed small aggregates in liquid cultures. Our cumulative data show thatepamutations result in altered polysaccharide content, increased cell surface hydrophobicity, and decreased membrane potential. Surprisingly, severalepamutations significantly increased resistance to the antibiotic ceftriaxone, indicating that the way in which theepaoperon impacts antibiotic resistance is antibiotic dependent. These results further define the key role ofepain antibiotic resistance in biofilms and in biofilm architecture.IMPORTANCEE. faecalisis a common cause of nosocomial infection, has a high level of antibiotic resistance, and forms robust biofilms. Biofilm formation is associated with increased antibiotic resistance. Therefore, a thorough understanding of biofilm-associated antibiotic resistance is important for combating resistance. Several genes from theepaoperon have previously been implicated in biofilm-associated antibiotic resistance, pathogenesis, and competitive fitness in the GI tract, but most genes in this locus remain uncharacterized. Here, we examineepaQ,which has not been characterized functionally. We show that the ΔepaQmutant exhibits reduced biofilm formation in the presence of daptomycin, altered biofilm architecture, and increased resistance to ceftriaxone, further expanding our understanding of the contribution of this operon to intrinsic enterococcal antibiotic resistance and biofilm growth.

Possible ecological implications of the high cell surface hydrophobicity of the fish pathogen Aeromonas salmonicida

1992 ◽  
Vol 38 (10) ◽  
pp. 1048-1052 ◽  
Author(s):  
Øivind Enger ◽  
Berit K. Thorsen
Keyword(s):  
Cell Surface ◽  
Water Column ◽  
Cell Surface Hydrophobicity ◽  
Surface Hydrophobicity ◽  
Aeromonas Salmonicida ◽  
Fish Farm ◽  
Surface Microlayer ◽  
Water Interface ◽  
Air Water Interface ◽  
Key Words Immunofluorescence

The abundance of the fish pathogenic bacterium Aeromonas salmonicida in different parts of the marine environment was determined in a fish farm stocked with Atlantic salmon (Salmo salar) suffering from furunculosis. By application of highly specific monoclonal antibodies and immunofluorescence techniques, the bacterium was found in high abundances (4.3 × 103 cells/mL) at the air-water interface. Aeromonas salmonicida was also registered in high numbers in the sediments beneath the farm, and in moderate to low numbers in the water column. When samples were collected in the environment outside the fish farm, the number of A. salmonicida was below the detection limit in surface samples, but the bacterium could be detected in the water column in samples collected downstream to the farm. The high number of A. salmonicida found in the lipid-rich air-water interface is discussed, taking into consideration the high hydrophobicity of the cell surface of the bacterium and the physical and ecological conditions in this specific habitat. Key words: immunofluorescence, total bacterial counts, surface microlayer, furunculosis.

Modulation of Cell Surface Hydrophobicity and Attachment of Bacteria to Abiotic Surfaces and Shrimp by Malaysian Herb Extracts

2012 ◽  
Vol 75 (8) ◽  
pp. 1507-1511 ◽  
Author(s):  
YEW WOH HUI ◽  
GARY A. DYKES
Keyword(s):  
Stainless Steel ◽  
Foodborne Pathogens ◽  
Salmonella Enteritidis ◽  
Cell Surface Hydrophobicity ◽  
Surface Hydrophobicity ◽  
Bacterial Attachment ◽  
Water Extracts ◽  
Bacterial Hydrophobicity ◽  
Herb Extracts ◽  
Herb Extract

The use of simple crude water extracts of common herbs to reduce bacterial attachment may be a cost-effective way to control bacterial foodborne pathogens, particularly in developing countries. The ability of water extracts of three common Malaysian herbs (Andrographis paniculata, Eurycoma longifolia, and Garcinia atroviridis) to modulate hydrophobicity and attachment to surfaces of five food-related bacterial strains (Bacillus cereus ATCC 14576, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 10145, Salmonella Enteritidis ATCC 13076, Staphylococcus aureus ATCC 25923) were determined. The bacterial attachment to hydrocarbon assay was used to determine bacterial hydrophobicity. Staining and direct microscopic counts were used to determine attachment of bacteria to glass and stainless steel. Plating on selective media was used to determine attachment of bacteria to shrimp. All extracts were capable of either significantly (P < 0.05) increasing or decreasing bacterial surface hydrophobicity, depending on the herb extract and bacteria combination. Bacterial attachment to all surfaces was either significantly (P < 0.05) increased or decreased, depending on the herb extract and bacteria combination. Overall, hydrophobicity did not show a significant correlation (P > 0.05) to bacterial attachment. For specific combinations of bacteria, surface material, and plant extract, significant correlations (R > 0.80) between hydrophobicity and attachment were observed. The highest of these was observed for S. aureus attachment to stainless steel and glass after treatment with the E. longifolia extract (R = 0.99, P < 0.01). The crude water herb extracts in this study were shown to have the potential to modulate specific bacterial and surface interactions and may, with further work, be useful for the simple and practical control of foodborne pathogens.

scholarly journals Operating parameter optimization of cell surface hydrophobicity test for ureolytic bacteria

2020 ◽  
pp. 82-82
Author(s):  
Olja Sovljanski ◽  
Lato Pezo ◽  
Ana Tomic ◽  
Aleksandra Ranitovic ◽  
Dragoljub Cvetkovic ◽  
...  
Keyword(s):  
Cell Surface ◽  
Cell Surface Hydrophobicity ◽  
Operating Parameter ◽  
Surface Hydrophobicity ◽  
Operating Parameters ◽  
Relevant Parameter ◽  
Metabolic Reaction ◽  
Bacterial Hydrophobicity ◽  
Ureolytic Bacteria

As one of the main non-covalent relations in microbiological-based systems, cell surface hydrophobicity (CSH) can be observed as a relevant parameter for biodegradation capability and suggested bacterial behaviour and biofilm formation during a bioremediation process. On the other hand, the role of ureolytic bacteria in bioremediation has subsequently led to the examination of this bacterial type in different engineering fields. In order to optimize the operating parameters of microbial adhesion to hydrocarbons test (MATH) for ureolytic bacteria, Box-Behnken experimental design was conducted for five ureolytic bacteria isolated from soils as well as the reference strain Sporosarcina pasteurii DSM 33. The optimization was completed with and without essential substrate for targeted metabolic reaction, with the aim to compare differences in bacterial hydrophobicity. The vortex time of 2 minutes, hydrocarbon volume of 0.5 mL, and phase separation time of 15 minutes are recommended as MATH operating parameters for all tested ureolytic bacteria. Although all bacteria are hydrophobic, lower CSH values in urea presence were observed for the same bacterium which can be explained by the interaction of urea with organic phase of the separation system as well as rapid ureolysis process which also occurs during ureolytic bacteria application in biotechnology systems.

scholarly journals Biofilm Formation by Neisseria meningitidis

2004 ◽  
Vol 72 (10) ◽  
pp. 6132-6138 ◽  
Author(s):  
Kyungcheol Yi ◽  
Andrew W. Rasmussen ◽  
Seshu K. Gudlavalleti ◽  
David S. Stephens ◽  
Igor Stojiljkovic
Keyword(s):  
Neisseria Meningitidis ◽  
Biofilm Formation ◽  
Laser Scanning ◽  
Cell Surface Hydrophobicity ◽  
Surface Hydrophobicity ◽  
Invasive Disease ◽  
Laser Scanning Confocal Microscopy ◽  
Scanning Confocal Microscopy ◽  
High Level

ABSTRACT Biofilm formation by the human pathogen Neisseria meningitidis was analyzed. Biofilm-forming meningococcal strains were identified and quantitated by crystal violet staining. Laser scanning confocal microscopy of the meningococcal biofilm revealed variable layers up to 90 μm in thickness. A total of 39 meningococcal isolates were studied; 23 were nasopharyngeal-carriage isolates, and 16 were invasive-disease isolates. Thirty percent of carriage isolates and 12.5% of invasive-disease isolates formed biofilms proficiently on a polystyrene surface. Generally, the strains that formed biofilms showed high-level cell surface hydrophobicity, characteristic of strains lacking a capsule. The inhibitory role of capsule in biofilm formation was further confirmed by comparing the biofilm-forming capabilities of a serogroup B wild-type strain of a disease-associated isolate to those of its capsule-deficient mutant (ctrA). Some strains of meningococci form biofilms, and this process is likely important in menigococcal colonization.

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