scholarly journals Effect of S-PRG Eluate on Biofilm Formation and Enzyme Activity of Oral Bacteria

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Masahiro Yoneda ◽  
Nao Suzuki ◽  
Yosuke Masuo ◽  
Akie Fujimoto ◽  
Kosaku Iha ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Composite Resin ◽  
Fusobacterium Nucleatum ◽  
Microtiter Plate ◽  
Oral Bacteria ◽  
Gelatin Film ◽  
Glass Ionomer ◽  
Microtiter Plate Assay ◽  
Substrate Hydrolysis ◽  
Adherence Ability

Recently, the antibacterial activity of a composite resin containing prereacted glass ionomer (S-PRG) filler was revealed. We examined the effect of an S-PRG eluate on various biologic activities ofStreptococcus mutansandPorphyromonas gingivalis. Adherence ability ofS. mutanswas evaluated by microtiter plate assay; protease and gelatinase activities ofP. gingivaliswere examined by synthetic substrate hydrolysis and gelatin film spot assay, respectively. Coaggregation ofP. gingivaliswithFusobacterium nucleatumwas also examined. S-PRG eluate was found to suppress streptococcal adherence. S-PRG eluate inhibited the protease and gelatinase activities ofP. gingivalisand the coaggregation betweenP. gingivalisandF. nucleatum. These results indicate that S-PRG eluate suppresses streptococcal adherence and inhibits the protease and coaggregation activities ofP. gingivalis. These findings may prompt research into novel strategies for preventing caries and periodontitis.

Evaluation of the Role of Staphylococci in the Pathomechanism of Conjunctivitis

2021 ◽  
Author(s):  
Ewa Jasińska ◽  
Agnieszka Bogut ◽  
Agnieszka Magryś ◽  
Alina Olender
Keyword(s):  
Antibiotic Resistance ◽  
Epithelial Cells ◽  
Biofilm Formation ◽  
Methicillin Resistance ◽  
Microtiter Plate ◽  
Host Cells ◽  
Diffusion Method ◽  
Microtiter Plate Assay ◽  
Low Prevalence

Abstract Purpose: Determination of the association between ica genes and phenotypic biofilm formation in staphylococcal isolates involved in conjunctivitis, their antibiotic resistance as well as detection of selected virulence characteristics: adhesion to epithelial cells and in vitro cytotoxicity.Methods: The study included 26 Staphylococcus aureus (SA) and 26 Staphylococcus epidermidis (SE) isolates. The presence of icaAD genes and ica operon was determined by the PCR assay. Phenotypic biofilm formation was verified using the microtiter plate assay. Antibiotic resistance was performed using the disc diffusion method. Staphylococcal ability to attach to host cells was assessed by flow cytometry. Cytotoxicity on epithelial cells was evaluated by LDH assay.Results: The ica genes were detected in 26.9% of SE and in 42.3% of SA isolates. Only 15.3% of isolates (SE) were positive for both the icaAD and the ica operon. Phenotypically, 19.2% of SE isolates were strong biofilm producers, among which three were both icaAD- and ica operon-positive. 26.9% of SA isolates were strong biofilm producers. Methicillin resistance (MR) was detected in 34.6% of SE and 26.9% of SA isolates. 75% of MR isolates were multidrug resistant. SA isolates adhered to host cells more extensively than SE. SA isolates released higher level of LDH than SE.Conclusions: Adherence abilities were commonly observed in staphylococci associated with conjunctivitis. However, low prevalence of isolates positive for a complete and functional ica locus and low prevalence of strong biofilm producers was detected. SA adhered to a greater extent to eukaryotic cells than SE and were more cytotoxic.

scholarly journals Effect of Silver Nanoparticles on Biofilm Formation and EPS Production of Multidrug-Resistant Klebsiella pneumoniae

2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Muhammad Hussnain Siddique ◽  
Bilal Aslam ◽  
Muhammad Imran ◽  
Asma Ashraf ◽  
Habibullah Nadeem ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Biofilm Formation ◽  
Extracellular Polymeric Substances ◽  
Microtiter Plate ◽  
Cellular Protein ◽  
Antibiofilm Activity ◽  
Biofilm Inhibition ◽  
Microtiter Plate Assay ◽  
Protein Leakage ◽  
Hela Cell Lines

Antibiotic resistance against present antibiotics is rising at an alarming rate with need for discovery of advanced methods to treat infections caused by resistant pathogens. Silver nanoparticles are known to exhibit satisfactory antibacterial and antibiofilm activity against different pathogens. In the present study, the AgNPs were synthesized chemically and characterized by UV-Visible spectroscopy, scanning electron microscopy, and X-ray diffraction. Antibacterial activity against MDR K. pneumoniae strains was evaluated by agar diffusion and broth microdilution assay. Cellular protein leakage was determined by the Bradford assay. The effect of AgNPs on production on extracellular polymeric substances was evaluated. Biofilm formation was assessed by tube method qualitatively and quantitatively by the microtiter plate assay. The cytotoxic potential of AgNPs on HeLa cell lines was also determined. AgNPs exhibited an MIC of 62.5 and 125 μg/ml, while their MBC is 250 and 500 μg/ml. The production of extracellular polymeric substance decreased after AgNP treatment while cellular protein leakage increased due to higher rates of cellular membrane disruption by AgNPs. The percentage biofilm inhibition was evaluated to be 64% for K. pneumoniae strain MF953600 and 86% for MF953599 at AgNP concentration of 100 μg/ml. AgNPs were evaluated to be minimally cytotoxic and safe at concentrations of 15-120 μg/ml. The data evaluated by this study provided evidence of AgNPs being safe antibacterial and antibiofilm compounds against MDR K. pneumoniae.

scholarly journals Prevalence of Adhesion and Regulation of Biofilm-Related Genes in Different Clones ofStaphylococcus aureus

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Salman Sahab Atshan ◽  
Mariana Nor Shamsudin ◽  
Zamberi Sekawi ◽  
Leslie Than Thian Lung ◽  
Rukman Awang Hamat ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Biofilm Formation ◽  
Clinical Information ◽  
Microtiter Plate ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Microtiter Plate Assay ◽  
High Prevalence ◽  
Different Types ◽  
Polymerase Chain

Clinical information about genotypically different clones of biofilm-producingStaphylococcus aureusis largely unknown. We examined whether different clones of methicillin-sensitive and methicillin-resistantS. aureus(MSSA and MRSA) differ with respect to staphylococcal microbial surface components recognizing adhesive matrix molecules (MSCRAMMs) in biofilm formation. The study used 60 different types ofspaand determined the phenotypes, the prevalence of the 13 MSCRAMM, and biofilm genes for each clone. The current investigation was carried out using a modified Congo red agar (MCRA), a microtiter plate assay (MPA), polymerase chain reaction (PCR), and reverse transcriptase polymerase chain reaction (RT-PCR). Clones belonging to the samespatype were found to have similar properties in adheringto thepolystyrene microtiter plate surface. However, their ability to produce slime on MCRA medium was different. PCR experiments showed that 60 clones of MSSA and MRSA were positive for 5 genes (out of 9 MSCRAMM genes).icaADBCgenes were found to be present in all the 60 clones tested indicating a high prevalence, and these genes were equally distributed among the clones associated with MSSA and those with MRSA. The prevalence of other MSCRAMM genes among MSSA and MRSA clones was found to be variable. MRSA and MSSA gene expression (MSCRAMM andicaADBC) was confirmed by RT-PCR.

scholarly journals Microtiter Plate Assay for Assessment of Listeria monocytogenes Biofilm Formation

2002 ◽  
Vol 68 (6) ◽  
pp. 2950-2958 ◽  
Author(s):  
D. Djordjevic ◽  
M. Wiedmann ◽  
L. A. McLandsborough
Keyword(s):  
Listeria Monocytogenes ◽  
Crystal Violet ◽  
Biofilm Formation ◽  
Microtiter Plate ◽  
Cellular Growth ◽  
Epifluorescence Microscopy ◽  
Simple Method ◽  
Microtiter Plate Assay ◽  
Plate Assay ◽  
Biofilm Production

ABSTRACT Listeria monocytogenes has the ability to form biofilms on food-processing surfaces, potentially leading to food product contamination. The objective of this research was to standardize a polyvinyl chloride (PVC) microtiter plate assay to compare the ability of L. monocytogenes strains to form biofilms. A total of 31 coded L. monocytogenes strains were grown in defined medium (modified Welshimer's broth) at 32°C for 20 and 40 h in PVC microtiter plate wells. Biofilm formation was indirectly assessed by staining with 1% crystal violet and measuring crystal violet absorbance, using destaining solution. Cellular growth rates and final cell densities did not correlate with biofilm formation, indicating that differences in biofilm formation under the same environmental conditions were not due to growth rate differences. The mean biofilm production of lineage I strains was significantly greater than that observed for lineage II and lineage III strains. The results from the standardized microtiter plate biofilm assay were also compared to biofilm formation on PVC and stainless steel as assayed by quantitative epifluorescence microscopy. Results showed similar trends for the microscopic and microtiter plate assays, indicating that the PVC microtiter plate assay can be used as a rapid, simple method to screen for differences in biofilm production between strains or growth conditions prior to performing labor-intensive microscopic analyses.

CHARACTERIZATION OF BACTERIAL ADHESION AND BIOFILM FORMATION ABILITY OF LIVESTOCK-ASSOCIATED METHICILLIN-RESISTANTSTAPHYLOCOCCUS AUREUSISOLATED FROM SWINE AND SLAUGHTERHOUSE WASTEWATERS

2014 ◽  
Vol 40 (02) ◽  
pp. 101-107
Author(s):  
Min-Tao Wan ◽  
Chin-Cheng Chou
Keyword(s):  
Bacterial Adhesion ◽  
Biofilm Formation ◽  
Microtiter Plate ◽  
Ecological Niches ◽  
Microtiter Plate Assay ◽  
Environmental Group ◽  
Biofilm Production ◽  
The Difference ◽  
Wastewater Samples

Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) ST9 has emerged as a potential zoonotic pathogen for humans and animals. Bacterial adhesion factors and biofilms mediate host colonization and infection of MRSA. This study investigated the dynamics of microbial surface components recognizing adhesive matrix molecules (MSCRAMMs), biofilm formation gene (intercellular adhesion [ica]), and biofilm expression in MRSA from the nasal samples of asymptomatic pigs (the nasal group, n = 147) and swine slaughterhouse wastewater samples (the environmental group, n = 86). Biofilm formation was quantified by microtiter plate assay. The most prevalent MSCRAMM profile was clfA-clfB-spa-eno-ebps-fib and more than 70% of the LA-MRSA ST9 isolates harbored the biofilm formation gene. Environmental MRSA harbored lower levels of the ica locus and MSCRAMMs (clfA and fib) than did the nasal group, suggesting possible gene loss. Biofilm production in the nasal group was higher than in the environmental group, indicating the difference in biofilm formation in MRSA isolates from different ecological niches. The higher prevalence of MSCRAMMs, biofilm formation gene, and biofilm production in LA-MRSA ST9 may enhance the persistence and infectivity of MRSA in the swine population and present a threat to the health of livestock as well as farm workers.

scholarly journals Adaptation of Congo Red Agar Method and Microtiter Plate Assay to Study Biofilm Formation in Streptomyces

2021 ◽  
Vol 18 (1) ◽  
pp. 113-123
Author(s):  
Rabha EL othmany ◽  
Hafida Zahir ◽  
Chorouk Zanane ◽  
Doha Mazigh ◽  
Mostafa Ellouali ◽  
...  
Keyword(s):  
Crystal Violet ◽  
Congo Red ◽  
Biofilm Formation ◽  
Staining Method ◽  
Microtiter Plate ◽  
Alcoholic Solution ◽  
Bioactive Molecules ◽  
Microtiter Plate Assay ◽  
Agar Method ◽  
Quantitative And Qualitative Methods

Streptomyces has many advantages for exploration in biotechnological applications because of their ability to elaborate a multitude of bioactive molecules and secondary metabolites. Despite the importance of this genus in biotechnology, biofilm formation in Streptomyces is under-investigated. The objective of this research is to adapt two assays for the assessment of biofilm formation in Streptomyces. In the present investigation, we assess and follow biofilm formation in eight Streptomyces strains using quantitative and qualitative methods. The quantitative study based on a staining of the retained biomass in the microtiter plate with crystal violet “5%” and destaining using ethanol/acetone mixture, the concentration of crystal violet in the alcoholic solution reflect the intensity of the attached biofilm. On the other hand, the qualitative one consists of using modified freeman’s method a modified congo red agar method based on the color of colonies. Quantification of biomass by crystal violet staining method confirmed that Streptomyces bellus A43 and Streptomyces bellus A61 are biofilm-forming and this ability increase with the period of incubation. Our results showed that sixStreptomyces strains arenon-slime producing/non-biofilm forming. Two Streptomyces strains are slime producing/biofilm forming; this character vanishes at five days. Further research on genes responsible for biofilm formation in Streptomyces is highly recommended for better understanding of the phenomenon.

scholarly journals Comparison of biofilm formation and efflux pumps in ESBL and carbapenemase producing Klebsiella pneumoniae

2018 ◽  
Vol 12 (03) ◽  
pp. 156-163 ◽  
Author(s):  
Burak Yazgan ◽  
Ibrahim Türkel ◽  
Rıdvan Güçkan ◽  
Kılınç Kılınç ◽  
Tuba Yıldırım
Keyword(s):  
Klebsiella Pneumoniae ◽  
Biofilm Formation ◽  
Cell Communication ◽  
Opportunistic Pathogen ◽  
Efflux Pumps ◽  
Microtiter Plate ◽  
Virulence Determinants ◽  
Clinical Environment ◽  
Microtiter Plate Assay ◽  
Significant Difference

Introduction: Klebsiella pneumoniae is an opportunistic pathogen that causes a range of diseases. The appearance of extended-spectrum β-lactamase -and carbapenemase-producing strains, in addition to the biofilm-forming phenotype, is a major problem in the clinical environment. Methodology: A total of 33 clinical K. pneumoniae isolates were used in this study. Antimicrobial susceptibilities were assessed by a disc diffusion assay. Biofilm formation was determined by a microtiter plate assay, staining with 1% crystal violet and measuring  absorbance after destaining. Moreover, expression of acrA, kdeA, ketM, kpnEF, and kexD efflux associated genes  was measured by qRT-PCR. Results: Isolates displayed high resistance to β-lactams such as cefazolin, cefuroxime, ceftriaxone, cefepime, piperacillin-tazobactam, imipenem, and meropenem and decreased resistance to gentamicin, amikacin, ciprofloxacin, and levofloxacin. ESBL-producing isolates formed more biofilm than carbapenemase-producing isolates. The mRNA expression levels in KPC isolates for acrA (2-fold), kdeA (2.7-fold), ketM (2.2-fold), and kpnEF (3.4-fold) were significantly increased compared to ESBL-producing isolates. There was no significant difference in kexD expression level. Conclusions: Under the conditions used here ESBL-producing isolates formed more biofilm than KPC postive isolates; this was associated with virulence determinants which were also transferred by plasmids together with ESBLs enzymes. Moreover, the upregulation of acrA, kdeA, ketM, and kpnEF efflux pumps was seen in carbapenemase-producing isolates demonstrating that high expression of efflux pumps alone could not confer resistance but may act as a physiological determinant such as bacterial pathogenicity and virulence, and cell-to-cell communication for bacteria.

In situ Biofilm Formation by Multi-species Oral Bacteria Under Flowing and Anaerobic Conditions

2004 ◽  
Vol 83 (10) ◽  
pp. 802-806 ◽  
Author(s):  
S.K. Filoche ◽  
M. Zhu ◽  
C.D. Wu
Keyword(s):  
Biofilm Formation ◽  
Fusobacterium Nucleatum ◽  
Therapeutic Agents ◽  
Oral Bacteria ◽  
Image Analysis System ◽  
Anaerobic Conditions ◽  
Planktonic Phase ◽  
Bacterial Aggregates ◽  
Analysis System

An understanding of biofilm behavior of periodontopathic bacteria is key to the development of effective oral therapies. We hypothesized that interspecies bacterial aggregates play an important role in anaerobic biofilm establishment and proliferation, and contribute to the survivability of the biofilm against therapeutic agents. The system developed in this study assessed a multi-species ( Streptococcus gordonii, Actinobacillus actinomycetemcomitans, and Fusobacterium nucleatum) biofilm formation under anaerobic and flowing conditions with the use of an in situ image analysis system. The biofilm was comprised of a base film of non-aggregated cells and complex interspecies aggregates that formed in the planktonic phase which rapidly colonized the surface, reaching 58 ± 9% and 65 ± 11.8% coverage by 5 and 24 hrs, respectively. Upon SDS (0.1%) treatment of a 24-hour biofilm, substantial detachment (55 ± 14%, P < 0.05) of the aggregates was observed, while the base film bacteria remained attached but non-viable. Rapid re-establishment of the biofilm occurred via attachment of viable planktonic aggregates.

Inhibitory Effects of Citral, Cinnamaldehyde, and Tea Polyphenols on Mixed Biofilm Formation by Foodborne Staphylococcus aureus and Salmonella Enteritidis

2014 ◽  
Vol 77 (6) ◽  
pp. 927-933 ◽  
Author(s):  
HONGMEI ZHANG ◽  
WENYUAN ZHOU ◽  
WENYAN ZHANG ◽  
ANLIN YANG ◽  
YANLAN LIU ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Biofilm Formation ◽  
Salmonella Enteritidis ◽  
Food Additives ◽  
Microtiter Plate ◽  
Tea Polyphenols ◽  
Natural Food ◽  
Inhibitory Effects ◽  
Microtiter Plate Assay ◽  
Communication Signal

Biofilms are significant hazards in the food industry. In this study, we investigated the effects of food additive such as citral, cinnamaldehyde, and tea polyphenols on mixed biofilm formation by foodborne Staphylococcus aureus and Salmonella serotype Enteritidis. The adhesion rates of mixed strains in sub-MIC of additives were determined by a microtiter plate assay and bacterial communication signal autoinducer 2 (AI-2) production via a bioluminescence reporter Vibrio harveyi BB170. The structure of mixed biofilm was analyzed using scanning electron microscopy. The effect of the disinfectants hydrogen peroxide, sodium hypochlorite, and peracetic acid was tested on the mixed biofilm. Our results demonstrated that citral, cinnamaldehyde, and tea polyphenols were able to significantly inhibit mixed biofilm formation, while citral could reduce the synthesis of AI-2. Conversely, we observed a significant increase in AI-2 mediated by cinnamaldehyde. Tea polyphenols at lower concentrations induced AI-2 synthesis; however, AI-2 synthesis was significantly inhibited at higher concentrations (300 μg/ml). Food additives inhibited the adhesion of mixed bacteria on stainless steel chips and increased the sensitivity of the mixed biofilm to disinfectants. In conclusion, citral, cinnamaldehyde, and tea polyphenols had strong inhibitory effects on mixed biofilm formation and also enhanced the effect of disinfectant on mixed biofilm formation. This study provides a scientific basis for the application of natural food additives to control biofilm formation of foodborne bacteria.

scholarly journals Genome-Wide Transposon Mutagenesis Reveals a Role for pO157 Genes in Biofilm Development in Escherichia coli O157:H7 EDL933

2010 ◽  
Vol 78 (6) ◽  
pp. 2377-2384 ◽  
Author(s):  
Supraja Puttamreddy ◽  
Nancy A. Cornick ◽  
F. Chris Minion
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Microtiter Plate ◽  
Virulence Plasmid ◽  
Microtiter Plate Assay ◽  
Severe Diarrhea ◽  
Wide Range ◽  
Intergenic Regions ◽  
Biofilm Development

ABSTRACT Enterohemorrhagic Escherichia coli O157:H7, a world-wide human food-borne pathogen, causes mild to severe diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome. The ability of this pathogen to persist in the environment contributes to its dissemination to a wide range of foods and food processing surfaces. Biofilms are thought to be involved in persistence, but the process of biofilm formation is complex and poorly understood in E. coli O157:H7. To better understand the genetics of this process, a mini-Tn5 transposon insertion library was constructed in strain EDL933 and screened for biofilm-negative mutants using a microtiter plate assay. Ninety-five of 11,000 independent insertions (0.86%) were biofilm negative, and transposon insertions were located in 51 distinct genes/intergenic regions that must be involved either directly or indirectly in biofilm formation. All of the 51 biofilm-negative mutants showed reduced biofilm formation on both hydrophilic and hydrophobic surfaces. Thirty-six genes were unique to this study, including genes on the virulence plasmid pO157. The type V secreted autotransporter serine protease EspP and the enterohemolysin translocator EhxD were found to be directly involved in biofilm formation. In addition, EhxD and EspP were also important for adherence to T84 intestinal epithelial cells, suggesting a role for these genes in tissue interactions in vivo.

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