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1.
Potential biological control of Erwinia tracheiphila by internal alimentary canal interactions in Acalymma vittatum with Pseudomonas fluorescens
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D.C. Roberts S.J. Fleischer J.M. Sakamoto J.L. Rasgon 《Journal of applied microbiology》2018,125(4):1137-1146
Aims
We aim to determine if Pseudomonas fluorescens is a viable biological control for Erwinia tracheiphila within the insect vector, Acalymma vittatum.Methods and Results
Pseudomonas fluorescens secreted fluorescein and inhibited growth of E. tracheiphila in disc diffusion assays. To determine if this antagonism was conserved within the insect vector, we performed in vivo assays by orally injecting beetles with bacterial treatments and fluorescent in situ hybridization to determine bacterial presence within the alimentary canal.Conclusions
Pseudomonas fluorescens inhibited the growth of E. tracheiphila on a nutrient‐limiting medium. In situ experiments demonstrated that P. fluorescens is maintained within the alimentary canal of the beetle for at least 4 days, and co‐occurred with E. tracheiphila. When beetles were first presented with Pseudomonas and then challenged with E. tracheiphila, E. tracheiphila was not recovered via FISH after 4 days. These data suggest that P. fluorescens has potential as a biological control agent to limit E. tracheiphila within the insect vector.Significance and Impact of the Study
This is a novel approach for controlling E. tracheiphila that has the potential to decrease reliance on insecticides, providing a safer environment for pollinators and growers. 相似文献2.
L. Pesciaroli M. Petruccioli F. Federici A. D'Annibale 《Journal of applied microbiology》2013,114(6):1750-1762
Aims
To investigate the effect of support and growth medium (GM) on Pleurotus ostreatus biofilm production, specific metabolic activity (SMA) and ultrastructure.Methods and Results
Biofilms were developed on membranes covering a broad range of surface properties and, due to the applicative implications of mixed biofilms, on standard bacterial GM in stationary and shaken culture. Hydrophilic (glass fibre, Duran glass and hydroxyapatite) and mild hydrophobic (polyurethane, stainless steel, polycarbonate, nylon) supports were more adequate for biofilm attachment than the hydrophobic Teflon. Among the GM, sucrose–asparagine (SA) was more conducive to biofilm production than Luria–Bertani and M9. GM was more influential than support type on biofilm ultrastructure, and a high compactness was evident in biofilms developed on SA. Biofilms on Duran glass were more efficient than planktonic cultures in olive‐mill wastewater treatment.Conclusions
The main effects of support and GM variables and their binary interactions on both biofilm production and SMA were all highly significant (P < 0·001): thus, the magnitude of the effect of each variable strongly depended on the level of the other one.Significance and Impact of the Study
There is a lack of basic information regarding physiology and ultrastructure of P. ostreatus biofilms. To our knowledge, this is the first attempt to fill this gap, thus representing a basis for future studies. 相似文献3.
Hessam Edin Daneshvar Alavi 《Biofouling》2013,29(10):1253-1268
This study investigated the dynamics of static biofilm formation (100% RH, 15 °C, 48–72 h) and desiccation survival (43% RH, 15 °C, 21 days) of Listeria monocytogenes, in dual species biofilms with the common spoilage bacteria, Pseudomonas fluorescens, Serratia proteamaculans and Shewanella baltica, on the surface of food grade stainless steel. The Gram-negative bacteria reduced the maximum biofilm population of L. monocytogenes in dual species biofilms and increased its inactivation during desiccation. However, due to the higher desiccation resistance of Listeria relative to P. fluorescens and S. baltica, the pathogen survived in greater final numbers. In contrast, S. proteamaculans outcompeted the pathogen during the biofilm formation and exhibited similar desiccation survival, causing the N21 days of Serratia to be ca 3 Log10(CFU cm?2) greater than that of Listeria in the dual species biofilm. Microscopy revealed biofilm morphologies with variable amounts of exopolymeric substance and the presence of separate microcolonies. Under these simulated food plant conditions, the fate of L. monocytogenes during formation of mixed biofilms and desiccation depended on the implicit characteristics of the co-cultured bacterium. 相似文献
4.
W. R. Z. Wan Dagang J. Bowen J. O’Keeffe P. T. Robbins Z. Zhang 《Biotechnology letters》2016,38(5):787-792
Objectives
The adhesion of colloidal probes of stainless steel, glass and cellulose to Pseudomonas fluorescens biofilms was examined using atomic force microscopy (AFM) to allow comparisons between surfaces to which biofilms might adhere.Results
Biofilm was grown on a stainless steel substrate and covered most of the surface after 96 h. AFM approach and retraction curves were obtained when the biofilm was immersed in a tryptone/soy medium. On approach, all the colloidal probes experienced a long non-contact phase more than 100 nm in length, possibly due to the steric repulsion by extracellular polymers from the biofilm and hydrophobic effects. Retraction data showed that the adhesion varied from position to position on the biofilm. The mean value of adhesion of glass to the biofilm (48 ± 7 nN) was the greatest, followed by stainless steel (30 ± 7 nN) and cellulose (7.8 ± 0.4 nN).Conclusion
The method allows understanding of adhesion between the three materials and biofilm, and development of a better strategy to remove the biofilm from these surfaces relevant to different industrial applications.5.
Carina Hüwe Jennifer Schmeichel Florian Brodkorb Sophia Dohlen Katrin Kalbfleisch Martin Kreyenschmidt 《Biofouling》2018,34(4):378-387
Antimicrobial surfaces are one approach to prevent biofilms in the food industry. The aim of this study was to investigate the effect of poly((tert-butyl-amino)-methyl-styrene) (poly(TBAMS)) incorporated into linear low-density polyethylene (LLDPE) on the formation of mono- and mixed-species biofilms. The biofilm on untreated and treated LLDPE was determined after 48 and 168 h. The comparison of the results indicated that the ability of Listeria monocytogenes to form biofilms was completely suppressed by poly(TBAMS) (Δ168 h 3.2 log10 cfu cm?2) and colonization of Staphylococcus aureus and Escherichia coli was significantly delayed, but no effect on Pseudomonas fluorescens was observed. The results of dual-species biofilms showed complex interactions between the microorganisms, but comparable effects on the individual bacteria by poly(TBAMS) were identified. Antimicrobial treatment with poly(TBAMS) shows great potential to prevent biofilms on polymeric surfaces. However, a further development of the material is necessary to reduce the colonization of strong biofilm formers. 相似文献
6.
Aims
The aim of our research was to select, identify and characterize an isolate of lactic acid bacteria to be considered as a vaginal probiotic.Methods and Results
Thirty‐five isolates of Pediococcus spp. showed bacteriocinogenic activity against Listeria monocytogenes and the ability to survive in simulated vaginal fluid (SVF) at pH 4·2. One isolate of Pediococcus spp. was selected and characterized to evaluate its safety before the use as vaginal probiotic. Pediococcus pentosaceus SB83 did not show the presence of virulence factors such as the production of gelatinase, lipase and DNase, haemolytic activity, nor the presence of virulence genes (genes esp, agg, gelE, efaAfm, efaAfs, cylA, cylB and cylM). Pediococcus pentosaceus SB83 was considered sensitive to chloramphenicol, gentamicin, streptomycin, kanamycin, erythromycin and ampicillin. This strain was considered resistant to tetracycline and vancomycin. Pediococcus pentosaceus SB83 was a biofilm producer at different pH values (4·2, 5·5 and 6·5) in SVF and in de Man, Rogosa and Sharpe medium.Conclusions
The in vitro results provide a basis for the use of P. pentosaceus SB83 as a vaginal probiotic, to prevent colonization by L. monocytogenes in pregnant women.Significance and Impact of Study
The application of vaginal probiotics could have the potential for preventing vaginal infections and consequently reduce abortion and neonatal infections. 相似文献7.
Katja Bezek Damjan Nipič Karmen Godič Torkar Martina Oder Goran Dražić Anže Abram 《Biofouling》2019,35(3):273-283
There is a wide range of factors affecting bacterial adhesion and biofilm formation. However, in both food processing and medical settings, it is very hard to obtain suitably controlled conditions so that the factors that reduce surface colonisation and biofouling can be studied. The aim of this study was to evaluate the effect of glucose concentration, temperature and stainless steel (SS) surface roughness on biofouling by four common pathogens (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and L. monocytogenes). Among the tested variables, the untreated SS surface (3C) was shown to be fouled more than 3D polished, brushed or electropolished SS surfaces. Although an array of parameters influenced biofouling, the most promising control measure was the influence of low temperature (4?°C) that reduced biofouling even in the case of the psychrophilic Listeria monocytogenes. The study findings could significantly contribute to the prevention of SS surface contamination and consequential biofouling by food and healthcare associated pathogens. 相似文献
8.
Aims
The aim of this study was to investigate the role of invasin in a bacterial fish pathogen Edwardsiella tarda.Methods and Results
In this study, an in‐frame deletion mutant of invasin (Δinv) in Edw. tarda H1 was constructed through double crossover allelic exchange to explore the function of invasin in virulence to fish. Meanwhile, an invasin overexpression strain (inv+) was obtained by electrotransformation of a low‐copy plasmid pACYC184 carrying the intact invasin into the Δinv mutant. Several virulence‐associated characters of the mutants and wild‐type strain were tested. Compared with the wild‐type H1, haemolytic activity and biofilm formation were decreased in Δinv, while increased significantly in inv+. In addition, the invasin overexpressing strain inv+ exhibited increased internalization into Epithelioma Papulosum Cyprini (EPC) cells. Moreover, in zebrafish model, Δinv showed decreased virulence compared with H1, while inv+ restored the virulence of wild type completely.Conclusions
The results demonstrated that invasin of Edw. tarda plays essential roles in haemolytic activity, biofilm formation, adherence, internalization and pathogenicity of this bacterium.Significance and Impact of the Study
This study revealed the role of invasin in Edw. tarda infection and provided useful information for further unveiling the pathogenesis of Edw. tarda. 相似文献9.
Aims
The present study was carried out to screen the phylloplane bacteria from tea for antagonism against grey blight caused by Pestalotiopsis theae and blister bight caused by Exobasidium vexans and to further evaluate the efficient isolates for disease control potential under field condition.Methods and Results
A total of 316 morphologically different phylloplane bacteria were isolated. Among the antagonists, the isolates designated as BMO‐075, BMO‐111 and BMO‐147 exhibited maximum inhibitory activity against both the pathogens under in vitro conditions and hence were selected for further evaluation under microplot field trial. Foliar application of 36‐h‐old culture of BMO‐111 (1 × 108 colony‐forming units ml?1) significantly reduced the blister blight disease incidence than the other isolates. The culture of BMO‐111 as well as its culture filtrate effectively inhibited the mycelial growth of various fungal plant pathogens. The isolate BMO‐111 was identified as Ochrobactrum anthropi based on the morphological and 16S rDNA sequence analyses.Conclusions
It could be concluded that the biocontrol agent O. anthropi BMO‐111 was effective against blister blight disease of tea.Significance and Impact of the Study
Further study is required to demonstrate the mechanism of its action and formulation for the biocontrol potential against blister blight disease of tea. 相似文献10.
Alaa Al-Seraih Yanath Belguesmia John Baah Sabine Szunerits Rabah Boukherroub Djamel Drider 《Antonie van Leeuwenhoek》2017,110(2):205-219
Enterococcus faecalis B3A-B3B produces the bacteriocin B3A-B3B with activity against Listeria monocytogenes, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA) and Clostridium perfringens, but apparently not against fungi or Gram-negative bacteria, except for Salmonella Newport. B3A-B3B enterocin has two different nucleotides but similar amino acid composition to the class IIb MR10A-MR10B enterocin. B3A-B3B consists of two peptides of predicted molecular mass of 5176.31 Da (B3A) and 5182.21 Da (B3B). Importantly, B3A-B3B impeded biofilm formation of the foodborne pathogen L. monocytogenes 162 grown on stainless steel. The antimicrobial treatment of stainless steel with nisin (1 or 16 mg ml?1) decreased the cell numbers by about 2 log CFU ml?1, thereby impeding the biofilm formation by L. monocytogenes 162 or its nisin-resistant derivative strain L. monocytogenes 162R. Furthermore, the combination of nisin and B3A-B3B enterocin reduced the MIC required to inhibit this pathogen grown in planktonic or biofilm cultures. 相似文献
11.
Whereas the transfer of Listeria from surfaces to foods and vice versa has been well documented, little is known about the mechanism of bacterial transfer.
The objective of this work is to gain a better understanding of the forces involved in listerial biofilms adhesion using atomic
force microscopy (AFM). L. monocytogenes Scott A was grown as biofilms on stainless steel surfaces by inoculating stainless steel coupons with Listeria and incubating the coupons for 48 h at 32 °C with a diluted 1:20 tryptic soy broth. After growth, biofilms were equilibrated
over saturated salt solutions at a constant relative humidity (%RH) before measurement of adhesion forces using AFM. The effects
of contact time, loading force, and biofilm relative humidity (%RH) suggested that neither contact time, loading force nor
biofilm %RH had a significant effect on biofilm adhesiveness at a cellular level (P > 0.05). In a second set of experiments, the influence of material type on biofilm adhesiveness was evaluated using two different
colloidal probes (SiO2 and polyethylene). Results showed that the maximum pull-off force and retraction work needed to retract the cantilever for
glass (−85.42 nN and 1.610−15 J, respectively) were significantly lower than those of polyethylene (−113.38 nN and 2.7 × 10–15 J, respectively; P < 0.001). The results of this study suggest that Listeria biofilms adhere more strongly to hydrophobic surfaces than hydrophilic surfaces when measured at a cellular level. These
results provide important insights that could lead to new ways to remediate and avoid listerial biofilm formation in the food
industry. 相似文献
12.
Aims
Antibiotics can act as signal molecules and affect bacterial gene expression, physiology and virulence. The purpose of this study was to determine whether subinhibitory antibiotic concentrations alter gene expression and physiology of Listeria monocytogenes.Methods and Results
Using an agar‐based screening assay with promoter fusions, 14 of 16 antibiotics induced or repressed expression of one or more stress and/or virulence genes. Despite ampicillin‐induced up‐regulation of PinlA‐lacZ expression, Caco‐2 cell invasion was not affected. Subinhibitory concentrations of ampicillin and tetracycline caused up‐ and down‐regulation of stress response genes, respectively, but both antibiotics caused increased sensitivity to acid stress. Six combinations of gene‐antibiotic were quantified in broth cultures and five of the six resulted in the same expression pattern as the agar‐based assay.Conclusions
Antibiotics affect virulence and/or stress gene expression; however, altered expression could not predict changes in phenotypic behaviour. Subinhibitory concentrations of antibiotics led to increased acid sensitivity, and we speculate that this is attributed to changes in cell envelope or reduced σB‐dependent gene expression.Significance and Impact of the Study
Although subinhibitory concentrations of antibiotics affect gene expression in L. monocytogenes, the changes did not increase virulence but did enhance the acid sensitivity. 相似文献13.
The aim of this study was to evaluate the effect of the acid and salt adaptation in a cheese‐based medium on the virulence potential of Listeria monocytogenes strains isolated from cheese and dairy processing environment using the Galleria mellonella model. Four L. monocytogenes strains were exposed to a cheese‐based medium in conditions of induction of an acid tolerance response and osmotolerance response (pH 5·5 and 3·5% w/v NaCl) and injected in G. mellonella insects. The survival of insects and the L. monocytogenes growth kinetics in insects were evaluated. The gene expression of hly, actA and inlA genes was determined by real‐time PCR. The adapted cells of two dairy strains showed reduced insect mortality (P < 0·05) in comparison with nonadapted cells. Listeria monocytogenes Scott A was the least virulent, whereas the cheese isolate C882 caused the highest insect mortality, and no differences (P > 0·05) was found between adapted and nonadapted cells. The gene expression results evidenced an overexpression of virulence genes in cheese‐based medium, but not in simulated insect‐induced conditions. Our results suggest that adaptation to low pH and salt in a cheese‐based medium can affect the virulence of L. monocytogenes, but this effect is strain dependent.
Significance and Impact of the Study
In this study, the impact of adaptation to low pH and salt in a cheese‐based medium on L. monocytogenes virulence was tested using the Wax Moth G. mellonella model. This model allowed the differentiation of the virulence potential between the L. monocytogenes strains. The effect of adaptation on virulence is strain dependent. The G. mellonella model revealed to be a prompt method to test food‐related factors on L. monocytogenes virulence. 相似文献14.
T. Coba de la Peña F.J. Redondo M.F. Fillat M.M. Lucas J.J. Pueyo 《Journal of applied microbiology》2013,115(1):236-246
Aim
To determine whether expression of a cyanobacterial flavodoxin in soil bacteria of agronomic interest confers protection against the widely used herbicides paraquat and atrazine.Methods and Results
The model bacterium Escherichia coli, the symbiotic nitrogen‐fixing bacterium Ensifer meliloti and the plant growth‐promoting rhizobacterium Pseudomonas fluorescens Aur6 were transformed with expression vectors containing the flavodoxin gene of Anabaena variabilis. Expression of the cyanobacterial protein was confirmed by Western blot. Bacterial tolerance to oxidative stress was tested in solid medium supplemented with hydrogen peroxide, paraquat or atrazine. In all three bacterial strains, flavodoxin expression enhanced tolerance to the oxidative stress provoked by hydrogen peroxide and by the reactive oxygen species‐inducing herbicides, witnessed by the enhanced survival of the transformed bacteria in the presence of these oxidizing agents.Conclusions
Flavodoxin overexpression in beneficial soil bacteria confers tolerance to oxidative stress and improves their survival in the presence of the herbicides paraquat and atrazine. Flavodoxin could be considered as a general antioxidant resource to face oxidative challenges in different micro‐organisms.Significance and Impact of the study
The use of plant growth‐promoting rhizobacteria or nitrogen‐fixing bacteria with enhanced tolerance to oxidative stress in contaminated soils is of significant agronomic interest. The enhanced tolerance of flavodoxin‐expressing bacteria to atrazine and paraquat points to potential applications in herbicide‐treated soils. 相似文献15.
Biofilm formation in an ice cream plant 总被引:1,自引:0,他引:1
The sites of biofilm formation in an ice cream plant were investigated by sampling both the production line and the environment. Experiments were carried out twice within a 20-day period. First, stainless steel coupons were fixed to surfaces adjacent to food contact surfaces, the floor drains and the doormat. They were taken for the analysis of biofilm at three different production stages. Then, biofilm forming bacteria were␣enumerated and also presence of Listeria monocytogenes was monitored. Biofilm forming isolates were selected on the basis of colony morphology and Gram’s reaction; Gram negative cocci and rod, Gram positive cocci and spore forming isolates were identified. Most of the biofilm formations were seen on the conveyor belt of a packaging machine 8 h after the beginning of the production, 6.5 × 103 cfu cm−2. Most of the Gram negative bacteria identified belong to Enterobacteriaceae family such as Proteus, Enterobacter, Citrobacter, Shigella, Escherichia, Edwardsiella. The other Gram negative microflora included Aeromonas, Plesiomonas, Moraxella, Pseudomonas or Alcaligenes spp. were also isolated. Gram positive microflora of the ice cream plant included Staphyloccus, Bacillus, Listeria and lactic acid bacteria such as Streptococcus, Leuconostoc or Pediococcus spp. The results from this study highlighted the problems of spread of pathogens like Listeria and Shigella and spoilage bacteria. In the development of cleaning and disinfection procedures in ice cream plants, an awareness of these biofilm-forming bacteria is essential for the ice cream plants. 相似文献
16.
AbstractThe effects of dual species interactions on biofilm formation by Aeromonas hydrophila in the presence of Pseudomonas aeruginosa, Pseudomonas fluorescens, Pectobacterium carotovorum, Salmonella Typhimurium, and Listeria monocytogenes were examined. High-performance liquid chromatography and liquid-chromatography-mass spectrometry were performed to identify N-acyl homoserine lactone (AHL) molecules secreted by monocultures and dual cultures grown in crab broth. Field emission scanning electron microscopy was performed to observe attachment and biofilm formation. P. aeruginosa and P. fluorescens inhibited biofilm formation by A. hydrophila on the crab surface, without affecting their own biofilm-forming abilities. Dual biofilms of S. Typhimurium, L. monocytogenes, or P. carotovorum did not affect A. hydrophila biofilm formation. Exoprotease, AHL, and AI-2 levels were significantly reduced in dual cultures of P. aeruginosa and P. fluorescens with A. hydrophila, supporting the relationship between quorum sensing and biofilm formation. Dual-species biofilms were studied in their natural environment and in the laboratory. 相似文献
17.
X.Q. Mao Z. Zhang H. Jiang R.Y. Chai H.P. Qiu J.Y. Wang X.F. Du B. Li G.C. Sun 《Journal of applied microbiology》2013,114(5):1480-1490
Aim
To examine the inhibition effects of rhizosphere fungal strain MF‐91 on the rice blast pathogen Magnaporthe grisea and sheath blight pathogen Rhizoctonia solani.Methods and Results
Rhizosphere fungal strain MF‐91 and its metabolites suppressed the in vitro mycelial growth of R. solani. The inhibitory effect of the metabolites was affected by incubation temperature, lighting time, initial pH and incubation time of rhizosphere fungal strain MF‐91. The in vitro mycelial growth of M. grisea was insignificantly inhibited by rhizosphere fungal strain MF‐91 and its metabolites. The metabolites of rhizosphere fungal strain MF‐91 significantly inhibited the conidial germination and appressorium formation of M. grisea. Moreover, the metabolites reduced the disease index of rice sheath blight by 35·02% in a greenhouse and 57·81% in a field as well as reduced the disease index of rice blast by 66·07% in a field. Rhizosphere fungal strain MF‐91 was identified as Chaetomium aureum based on the morphological observation, the analysis of 18S ribosomal DNA internal transcribed spacer sequence and its physiological characteristics, such as the optimal medium, temperature and initial pH for mycelial growth and sporulation production.Conclusions
Rhizosphere fungus C. aureum is effective in the biocontrolling of rice blast pathogen M. grisea and sheath blight pathogen R. solani both in in vitro and in vivo conditions.Significance and Impact of the Study
This study is the first to show that rhizosphere fungus C. aureum is a potential fungicide against rice blast and sheath blight pathogens. 相似文献18.
Glutaraldehyde (GLUT) was evaluated for control of single and dual species biofilms of Bacillus cereus and Pseudomonas fluorescens on stainless steel surfaces using a chemostat system. The biofilms were characterized in terms of mass, cell density, total and matrix proteins and polysaccharides. The control action of GLUT was assessed in terms of inactivation and removal of biofilm. Post-biocide action was characterized 3, 7, 12, 24, 48 and 72 h after treatment. Tests with planktonic cells were also performed for comparison. The results demonstrated that in dual species biofilms the metabolic activity, cell density and the content of matrix proteins were higher than those of either single species. Planktonic B. cereus was more susceptible to GLUT than P. fluorescens. The biocide susceptibility of dual species planktonic cultures was an average of each single species. Planktonic cells were more susceptible to GLUT than their biofilm counterparts. Biofilm inactivation was similar for both of the single biofilms while dual biofilms were more resistant than single species biofilms. GLUT at 200 mg l?1 caused low biofilm removal (<10%). Analysis of the post-biocide treatment data revealed the ability of biofilms to recover their activity over time. However, 12 h after biocide application, sloughing events were detected for both single and dual species biofilms, but were more marked for those formed by P. fluorescens (removal >40% of the total biofilm). The overall results suggest that GLUT exerts significant antimicrobial activity against planktonic bacteria and a partial and reversible activity against B. cereus and P. fluorescens single and dual species biofilms. The biocide had low antifouling effects when analysed immediately after treatment. However, GLUT had significant long-term effects on biofilm removal, inducing significant sloughing events (recovery in terms of mass 72 h after treatment for single biofilms and 42 h later for dual biofilms). In general, dual species biofilms demonstrated higher resistance and resilience to GLUT exposure than either of the single species biofilms. P. fluorescens biofilms were more susceptible to the biocide than B. cereus biofilms. 相似文献
19.
A. Nur K. Hirota H. Yumoto K. Hirao D. Liu K. Takahashi K. Murakami T. Matsuo R. Shu Y. Miyake 《Journal of applied microbiology》2013,115(1):260-270
Aims
The aim of this study was to clarify the effects of homologous and heterologous extracellular DNAs (eDNAs) and histone‐like DNA‐binding protein (HLP) on Streptococcus intermedius biofilm development and rigidity.Methods and Results
Formed biofilm mass was measured with 0·1% crystal violet staining method and observed with a scanning electron microscope. The localizations of eDNA and extracellular HLP (eHLP) in formed biofilm were detected by staining with 7‐hydoxyl‐9H‐(1,3‐dichloro‐9,9‐dimethylacridin‐2‐one) and anti‐HLP antibody without fixation, respectively. DNase I treatment (200 U ml?1) markedly decreased biofilm formation and cell density in biofilms. Colocalization of eHLP and eDNA in biofilm was confirmed. The addition of eDNA (up to 1 μg ml?1) purified from Strep. intermedius, other Gram‐positive bacteria, Gram‐negative bacteria, or human KB cells into the Strep. intermedius culture increased the biofilm mass of all tested strains of Strep. intermedius, wild‐type, HLP‐downregulated strain and control strains. In contrast, the addition of eDNA (>1 μg ml?1) decreased the biofilm mass of all Strep. intermedius strains.Conclusions
These findings demonstrated that eDNA and eHLP play crucial roles in biofilm development and its rigidity.Significance and Impact of the Study
eDNA‐ and HLP‐targeting strategies may be applicable to novel treatments for bacterial biofilm‐related infectious diseases. 相似文献20.
Cowan MM Abshire KZ Houk SL Evans SM 《Journal of industrial microbiology & biotechnology》2003,30(2):102-106
A silver- and zinc-containing zeolite matrix (AgION) used as a coating for stainless steel was tested for antimicrobial efficacy
against Escherichia coli 25922, Staphylococcus aureus 25923, Pseudomonas aeruginosa 27853, and Listeria monocytogenes 7644. Assays were performed on flat coupon surfaces and in formed steel cups. AgION reduced microbial colony-forming units
when compared to uncoated steel surfaces under all conditions tested. Percent reductions ranged from 84.536 to 99.999 after
4 h exposure, and from 99.992 to 100 after 24 h in all cases. The durability of the coatings declined most markedly when the
coating had been applied with a wet process and scrubbed between uses with a test tube brush. Powder-coated surfaces cleaned
with a towel retained a high degree of activity after five cycles of use.
Electronic Publication 相似文献