Initial development and structure of biofilms on microbial fuel cell anodes DOI Creative Commons

Suzanne Read,

Paritam K. Dutta,

Philip L. Bond

et al.

BMC Microbiology, Journal Year: 2010, Volume and Issue: 10(1)

Published: April 1, 2010

Abstract Background Microbial fuel cells (MFCs) rely on electrochemically active bacteria to capture the chemical energy contained in organics and convert it electrical energy. Bacteria develop biofilms MFC electrodes, allowing considerable conversion capacity opportunities for extracellular electron transfer (EET). The present knowledge EET is centred around two Gram-negative models, i.e. Shewanella Geobacter species, as believed that Gram-positives cannot perform by themselves Gram-negatives can. To understand how form within MFCs their development, structure viability affects transfer, we performed pure co-culture experiments. Results Biofilm was maintained highest nearer anode during closed circuit operation (current flowing), contrast when open (soluble acceptor) where top of biofilm, furthest from anode. Closed Pseudomonas aeruginosa were considerably thinner compared (30 ± 3 μm 42 respectively), which likely due higher energetic gain soluble acceptors used. Gram-positive used only provided a fraction current produced organisms. Power output co-cultures Enterococcus faecium either organisms, increased 30-70% relative single cultures. Over time segregated, particular, creating towers piercing through thin, uniform layer faecium. P. E. together generated 1.8 0.4 mA while alone they 0.9 0.01 0.2 0.05 respectively. Conclusion We postulate this segregation may be an essential difference strategy substrate between here.

Language: Английский

Microbial Biofilms: from Ecology to Molecular Genetics DOI
Mary E. Davey, George A. O’Toole

Microbiology and Molecular Biology Reviews, Journal Year: 2000, Volume and Issue: 64(4), P. 847 - 867

Published: Dec. 1, 2000

SUMMARY Biofilms are complex communities of microorganisms attached to surfaces or associated with interfaces. Despite the focus modern microbiology research on pure culture, planktonic (free-swimming) bacteria, it is now widely recognized that most bacteria found in natural, clinical, and industrial settings persist association surfaces. Furthermore, these microbial often composed multiple species interact each other their environment. The determination biofilm architecture, particularly spatial arrangement microcolonies (clusters cells) relative one another, has profound implications for function communities. Numerous new experimental approaches methodologies have been developed order explore metabolic interactions, phylogenetic groupings, competition among members biofilm. To complement this broad view ecology, individual organisms studied using molecular genetics identify genes required development dissect regulatory pathways control plankton-to-biofilm transition. These genetic studies led emergence concept formation as a novel system study bacterial development. recent explosion field exciting progress technologies studying communities, advanced our understanding ecological significance surface-attached provided insights into basis

Language: Английский

Citations

3025
Transparent exopolymer particles (TEP) in aquatic environments DOI

Uta Passow

Progress In Oceanography, Journal Year: 2002, Volume and Issue: 55(3-4), P. 287 - 333

Published: Nov. 1, 2002

Language: Английский

Citations

1046
Inhibition of Candida albicans Biofilm Formation by Farnesol, a Quorum-Sensing Molecule DOI
Gordon Ramage,

Stephen P. Saville,

Brian L. Wickes

et al.

Applied and Environmental Microbiology, Journal Year: 2002, Volume and Issue: 68(11), P. 5459 - 5463

Published: Nov. 1, 2002

Farnesol is a quorum-sensing molecule that inhibits filamentation in Candida albicans. Both and quorum sensing are deemed to be important factors C. albicans biofilm development. Here we examined the effect of farnesol on formation. adherent cell populations (after 0, 1, 2, 4 h adherence) preformed biofilms (24 h) were treated with various concentrations (0, 3, 30, 300 micro M) incubated at 37 degrees C for 24 h. The extent characteristics formation then assessed microscopically semiquantitative colorimetric technique based use 2,3-bis(2-methoxy-4-nitro-5-sulfo-phenyl)-2H-tetrazolium-5-carboxanilide. results indicated was dependent concentration this compound initial adherence time, preincubation M completely inhibited Supernatant media recovered from mature ability planktonic form filaments, indicating morphogenetic autoregulatory produced situ biofilms. Northern blot analysis RNA extracted cells levels expression HWP1, encoding hypha-specific wall protein, decreased farnesol-treated compared controls. Our indicate acts as naturally occurring which formation, discuss its potential further development novel therapeutic agent.

Language: Английский

Citations

659
Exopolysaccharide Production Is Required for Development of Escherichia coli K-12 Biofilm Architecture DOI Open Access

Paul N. Danese,

Leslie A. Pratt,

Roberto Kolter

et al.

Journal of Bacteriology, Journal Year: 2000, Volume and Issue: 182(12), P. 3593 - 3596

Published: June 15, 2000

ABSTRACT Although exopolysaccharides (EPSs) are a large component of bacterial biofilms, their contribution to biofilm structure and function has been examined for only few organisms. In each these cases EPS shown be required cellular attachment abiotic surfaces. Here, we undertook genetic approach examine the potential role colanic acid, an Escherichia coli K-12, in formation. Strains either proficient or deficient acid production were grown allowed adhere surfaces then both macroscopically microscopically. Surprisingly, found that is not surface attachment. Rather, critical formation complex three-dimensional depth E. biofilms.

Language: Английский

Citations

641
Horizontal Gene Exchange in Environmental Microbiota DOI Creative Commons
Rustam Aminov

Frontiers in Microbiology, Journal Year: 2011, Volume and Issue: 2

Published: Jan. 1, 2011

Horizontal gene transfer (HGT) plays an important role in the evolution of life on Earth. This view is supported by numerous occasions HGT that are recorded genomes all three domains living organisms. HGT-mediated rapid especially noticeable among Bacteria, which demonstrate formidable adaptability face recent environmental changes imposed human activities, such as use antibiotics, industrial contamination, and intensive agriculture. At heart HGT-driven bacterial adaptation highly sophisticated natural genetic engineering tools form a variety mobile elements (MGEs). The main aim this review to give brief account occurrence diversity MGEs ecosystems factors may affect MGE-mediated HGT.

Language: Английский

Citations

545
The Acinetobacter baumannii Oxymoron: Commensal Hospital Dweller Turned Pan-Drug-Resistant Menace DOI Creative Commons
Ignasi Roca, Paula Espinal,

Xavier Vila‐Farrés

et al.

Frontiers in Microbiology, Journal Year: 2012, Volume and Issue: 3

Published: Jan. 1, 2012

During the past few decades A. baumannii has evolved from being a commensal dweller of health-care facilities to constitute one most annoying pathogens responsible for hospitalary outbreaks and it is currently considered important nosocomial pathogens. In prevalence study infections in intensive care units conducted among 75 countries five continents, this microorganism was found be fifth common pathogen. Two main features contribute success baumannii: i) exhibits an outstanding ability accumulate great variety resistance mechanisms acquired by different mechanisms, either mutations or acquisition genetic elements such as plasmids, integrons, transposons resistant islands, making multi- pan-drug ii) The survive environment during prolonged periods time which, combined with its innate desiccation disinfectants, makes almost impossible eradicate clinical setting. addition, produce biofilm greatly contributes both persistence resistance. review, pathogenesis caused well molecular bases antibacterial aspects treatment potential future therapeutic strategies are discussed depth.

Language: Английский

Citations

354
Biofilms in the large bowel suggest an apparent function of the human vermiform appendix DOI

R. Randal Bollinger,

Andrew S. Barbas, Errol L. Bush

et al.

Journal of Theoretical Biology, Journal Year: 2007, Volume and Issue: 249(4), P. 826 - 831

Published: Sept. 8, 2007

Language: Английский

Citations

343
Paenibacillus polymyxa Invades Plant Roots and Forms Biofilms DOI
Salme Timmusk,

Nina Grantcharova,

E. Gerhart H. Wagner

et al.

Applied and Environmental Microbiology, Journal Year: 2005, Volume and Issue: 71(11), P. 7292 - 7300

Published: Nov. 1, 2005

Paenibacillus polymyxa is a plant growth-promoting rhizobacterium with broad host range, but so far the use of this organism as biocontrol agent has not been very efficient. In previous work we showed that bacterium protects Arabidopsis thaliana against pathogens and abiotic stress (S. Timmusk E. G. H. Wagner, Mol. Plant-Microbe Interact. 12:951-959, 1999; S. Timmusk, P. van West, N. A. R. Gow, p. 1-28, in Mechanism action growth promoting polymyxa, 2003). Here, studied colonization roots by natural isolate which had tagged plasmid-borne gfp gene. Fluorescence microscopy electron scanning indicated bacteria colonized predominantly root tip, where they formed biofilms. Accumulation was observed intercellular spaces outside vascular cylinder. Systemic spreading did occur, absence aerial tissues. Studies were performed both gnotobiotic system soil system. The fact similar observations made systems suggests can be more defined Problems associated green fluorescent protein tagging isolates deleterious effects are discussed.

Language: Английский

Citations

340
Role of Extracellular DNA in Initial Bacterial Adhesion and Surface Aggregation DOI Open Access
Theerthankar Das, Prashant K. Sharma, Henk J. Busscher

et al.

Applied and Environmental Microbiology, Journal Year: 2010, Volume and Issue: 76(10), P. 3405 - 3408

Published: April 7, 2010

Extracellular DNA (eDNA) is an important component of the biofilm matrix. We show that removal eDNA from Gram-positive bacteria reduces initial adhesion to and aggregation on surfaces. Thermodynamic analyses indicated introduces favorable acid-base interactions, explaining effect surface.

Language: Английский

Citations

309
Biofilm Formation As a Response to Ecological Competition DOI Creative Commons
Nuno M. Oliveira, Esteban Martínez‐García, João B. Xavier

et al.

PLoS Biology, Journal Year: 2015, Volume and Issue: 13(7), P. e1002191 - e1002191

Published: July 9, 2015

Bacteria form dense surface-associated communities known as biofilms that are central to their persistence and how they affect us. Biofilm formation is commonly viewed a cooperative enterprise, where strains species work together for common goal. Here we explore an alternative model: biofilm response ecological competition. We co-cultured diverse collection of natural isolates the opportunistic pathogen Pseudomonas aeruginosa studied effect on formation. show strain mixing reliably increases compared unmixed conditions. Importantly, leads strong competition: one dominates largely excludes other from biofilm. Furthermore, pyocins, narrow-spectrum antibiotics made by P. strains, can stimulate increasing attachment cells. Side-by-side comparisons using microfluidic assays suggest increase in occurs due general cellular damage: comparable pyocins disrupt membranes commercial damage DNA, inhibit protein synthesis or transcription. Our data bacteria competition detected antibiotic stress. This inconsistent with idea sub-lethal concentrations signals coordinate microbial communities, often concluded. Instead, our consistent sensing low-levels used detect respond competing genotypes produce them.

Language: Английский

Citations

288