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Annual Review of Biophysics May 2021Biofilms are structured communities formed by a single or multiple microbial species. Within biofilms, bacteria are embedded into extracellular matrix, allowing them to... (Review)
Review
Biofilms are structured communities formed by a single or multiple microbial species. Within biofilms, bacteria are embedded into extracellular matrix, allowing them to build macroscopic objects. Biofilm structure can respond to environmental changes such as the presence of antibiotics or predators. By adjusting expression levels of surface and extracellular matrix components, bacteria tune cell-to-cell interactions. One major challenge in the field is the fact that these components are very diverse among different species. Deciphering how physical interactions within biofilms are affected by changes in gene expression is a promising approach to obtaining a more unified picture of how bacteria modulate biofilms. This review focuses on recent advances in characterizing attractive and repulsive forces between bacteria in correlation with biofilm structure, dynamics, and spreading. How bacteria control physical interactions to maximize their fitness is an emerging theme.
Topics: Bacteria; Biofilms; Colony Count, Microbial; Extracellular Matrix
PubMed: 33637007
DOI: 10.1146/annurev-biophys-062920-063646 -
Medical Mycology Oct 2021Biofilms are important virulence factor in infections caused by microorganisms because of its complex structure, which provide resistance to conventional antimicrobials.... (Review)
Review
UNLABELLED
Biofilms are important virulence factor in infections caused by microorganisms because of its complex structure, which provide resistance to conventional antimicrobials. Strategies involving the use of molecules capable of inhibiting their formation and also act synergistically with conventional drugs have been explored. Farnesol is a molecule present in essential oils and produced by Candida albicans as a quorum sensing component. This sesquiterpene presents inhibitory properties in the formation of microbial biofilms and synergism with antimicrobials used in clinical practice, and can be exploited even for eradication of biofilms formed by drug-resistant microorganisms. Despite this, farnesol has physical and chemical characteristics that can limit its use, such as high hydrophobicity and volatility. Therefore, nanotechnology may represent an option to improve the efficiency of this molecule in high complex environments such as biofilms. Nanostructured systems present important results in the improvement of treatment with different commercial drugs and molecules with therapeutic or preventive potential. The formation of nanoparticles offers advantages such as protection of the incorporated drugs against degradation, improved biodistribution and residence time in specific treatment sites. The combination of farnesol with nanotechnology may be promising for the development of more effective antibiofilm therapies, as it can improve its solubility, reduce volatility, and increase bioavailability. This review summarizes existing data about farnesol, its action on biofilms, and discusses its encapsulation in nanostructured systems.
LAY SUMMARY
Farnesol is a natural compound that inhibits the formation of biofilms from different microbial species. The encapsulation of this molecule in nanoparticles is a promising alternative for the development of more effective therapies against biofilms.
Topics: Animals; Biofilms; Candida albicans; Farnesol; Nanotechnology; Tissue Distribution
PubMed: 33877362
DOI: 10.1093/mmy/myab020 -
Photodiagnosis and Photodynamic Therapy Mar 2021Microorganisms thrive in well-organized biofilm ecosystems. Biofilm-associated cells typically show increased resistance to antibiotics and contribute significantly to... (Review)
Review
Microorganisms thrive in well-organized biofilm ecosystems. Biofilm-associated cells typically show increased resistance to antibiotics and contribute significantly to treatment failure. This has prompted investigations aimed at developing advanced and novel antimicrobial approaches that could effectively overcome the shortcomings associated with conventional antibiotic therapy. Studies are ongoing to develop effective curative strategies ranging from the use of peptides, small molecules, nanoparticles to bacteriophages, sonic waves, and light energy targeting various structural and physiological aspects of biofilms. In photodynamic therapy, a light source of a specific wavelength is used to irradiate non-toxic photosensitizers such as tetrapyrroles, synthetic dyes or, naturally occurring compounds to generate reactive oxygen species that can exert a lethal effect on the microbe especially by disrupting the biofilm. The photosensitizer preferentially binds to and accumulates in the microbial cells without causing any damage to the host tissue. Currently, photodynamic therapy is increasingly being used for the treatment of oral caries and dental plaque, chronic wound infections, infected diabetic foot ulcers, cystic fibrosis, chronic sinusitis, implant device-associated infections, etc. This approach is recognized as safe, as it is non-toxic and minimally invasive, making it a reliable, realistic, and promising therapeutic strategy for reducing the microbial burden and biofilm formation in chronic infections. In this review article, we discuss the current and future potential strategies of utilizing photodynamic therapy to extend our ability to impede and eliminate biofilms in various medical conditions.
Topics: Anti-Infective Agents; Biofilms; Ecosystem; Photochemotherapy; Photosensitizing Agents
PubMed: 33157331
DOI: 10.1016/j.pdpdt.2020.102090 -
Biosensors Jun 2024Microbial biofilms present one of the most widespread forms of life on Earth. The formation of microbial communities on various surfaces presents a major challenge in a... (Review)
Review
Microbial biofilms present one of the most widespread forms of life on Earth. The formation of microbial communities on various surfaces presents a major challenge in a variety of fields, including medicine, the food industry, shipping, etc. At the same time, this process can also be used for the benefit of humans-in bioremediation, wastewater treatment, and various biotechnological processes. The main direction of using electroactive microbial biofilms is their incorporation into the composition of biosensor and biofuel cells This review examines the fundamental knowledge acquired about the structure and formation of biofilms, the properties they have when used in bioelectrochemical devices, and the characteristics of the formation of these structures on different surfaces. Special attention is given to the potential of applying the latest advances in genetic engineering in order to improve the performance of microbial biofilm-based devices and to regulate the processes that take place within them. Finally, we highlight possible ways of dealing with the drawbacks of using biofilms in the creation of highly efficient biosensors and biofuel cells.
Topics: Biofilms; Biosensing Techniques; Bioelectric Energy Sources
PubMed: 38920606
DOI: 10.3390/bios14060302 -
Journal of Materials Chemistry. B Jul 2022Biofilms are formed at interfaces by microorganisms, which congregate in microstructured communities embedded in a self-produced extracellular polymeric substance (EPS).... (Review)
Review
Biofilms are formed at interfaces by microorganisms, which congregate in microstructured communities embedded in a self-produced extracellular polymeric substance (EPS). Biofilm-related infections are problematic due to the high resistance towards most clinically used antimicrobials, which is associated with high mortality and morbidity, combined with increased hospital stays and overall treatment costs. Several new nanotechnology-based approaches have recently been proposed for targeting resistant bacteria and microbial biofilms. Here we discuss the impacts of biofilms on healthcare, food processing and packaging, and water filtration and distribution systems, and summarize the emerging nanotechnological strategies that are being developed for biofilm prevention, control and eradication. Combination of novel nanomaterials with conventional antimicrobial therapies has shown great potential in producing more effective platforms for controlling biofilms. Recent developments include antimicrobial nanocarriers with enzyme surface functionality that allow passive infection site targeting, degradation of the EPS and delivery of high concentrations of antimicrobials to the residing cells. Several stimuli-responsive antimicrobial formulation strategies have taken advantage of the biofilm microenvironment to enhance interaction and passive delivery into the biofilm sites. Nanoparticles of ultralow size have also been recently employed in formulations to improve the EPS penetration, enhance the carrier efficiency, and improve the cell wall permeability to antimicrobials. We also discuss antimicrobial metal and metal oxide nanoparticle formulations which provide additional mechanical factors through externally induced actuation and generate reactive oxygen species (ROS) within the biofilms. The review helps to bridge microbiology with materials science and nanotechnology, enabling a more comprehensive interdisciplinary approach towards the development of novel antimicrobial treatments and biofilm control strategies.
Topics: Anti-Bacterial Agents; Anti-Infective Agents; Biofilms; Extracellular Polymeric Substance Matrix; Nanotechnology
PubMed: 35735175
DOI: 10.1039/d2tb00233g -
Biological Chemistry Nov 2020Biofilms are a ubiquitous mode of microbial life and display an increased tolerance to different stresses. Inside biofilms, cells may experience both externally applied... (Review)
Review
Biofilms are a ubiquitous mode of microbial life and display an increased tolerance to different stresses. Inside biofilms, cells may experience both externally applied stresses and internal stresses that emerge as a result of growth in spatially structured communities. In this review, we discuss the spatial scales of different stresses in the context of biofilms, and if cells in biofilms respond to these stresses as a collection of individual cells, or if there are multicellular properties associated with the response. Understanding the organizational level of stress responses in microbial communities can help to clarify multicellular functions of biofilms.
Topics: Bacteria; Biofilms; Humans; Stress, Physiological
PubMed: 32990640
DOI: 10.1515/hsz-2020-0213 -
ACS Sensors Feb 2022Microbial biofilms have caused serious concerns in healthcare, medical, and food industries because of their intrinsic resistance against conventional antibiotics and... (Review)
Review
Microbial biofilms have caused serious concerns in healthcare, medical, and food industries because of their intrinsic resistance against conventional antibiotics and cleaning procedures and their capability to firmly adhere on surfaces for persistent contamination. These global issues strongly motivate researchers to develop novel methodologies to investigate the kinetics underlying biofilm formation, to understand the response of the biofilm with different chemical and physical treatments, and to identify biofilm-specific drugs with high-throughput screenings. Meanwhile microbial biofilms can also be utilized positively as sensing elements in cell-based sensors due to their strong adhesion on surfaces. In this perspective, we provide an overview on the connections between sensing and microbial biofilms, focusing on tools used to investigate biofilm properties, kinetics, and their response to chemicals or physical agents, and biofilm-based sensors, a type of biosensor using the bacterial biofilm as a biorecognition element to capture the presence of the target of interest by measuring the metabolic activity of the immobilized microbial cells. Finally we discuss possible new research directions for the development of robust and rapid biofilm related sensors with high temporal and spatial resolutions, pertinent to a wide range of applications.
Topics: Anti-Bacterial Agents; Bacteria; Biofilms; Biosensing Techniques
PubMed: 35171575
DOI: 10.1021/acssensors.1c02722 -
Nature Reviews. Microbiology Oct 2022Historically, appreciation for the roles of resource gradients in biology has fluctuated inversely to the popularity of genetic mechanisms. Nevertheless, in microbiology... (Review)
Review
Historically, appreciation for the roles of resource gradients in biology has fluctuated inversely to the popularity of genetic mechanisms. Nevertheless, in microbiology specifically, widespread recognition of the multicellular lifestyle has recently brought new emphasis to the importance of resource gradients. Most microorganisms grow in assemblages such as biofilms or spatially constrained communities with gradients that influence, and are influenced by, metabolism. In this Review, we discuss examples of gradient formation and physiological differentiation in microbial assemblages growing in diverse settings. We highlight consequences of physiological heterogeneity in microbial assemblages, including division of labour and increased resistance to stress. Our impressions of microbial behaviour in various ecosystems are not complete without complementary maps of the chemical and physical geographies that influence cellular activities. A holistic view, incorporating these geographies and the genetically encoded functions that operate within them, will be essential for understanding microbial assemblages in their many roles and potential applications.
Topics: Biofilms; Ecosystem
PubMed: 35149841
DOI: 10.1038/s41579-022-00692-2 -
Chemical Society Reviews Feb 2021Biofilms are complex three-dimensional structures formed at interfaces by the vast majority of bacteria and fungi. These robust communities have an important detrimental... (Review)
Review
Biofilms are complex three-dimensional structures formed at interfaces by the vast majority of bacteria and fungi. These robust communities have an important detrimental impact on a wide range of industries and other facets of our daily lives, yet their removal is challenging owing to the high tolerance of biofilms towards conventional antimicrobial agents. This key issue has driven an urgent search for new innovative antibiofilm materials. Amongst these emerging approaches are highly promising materials that employ aqueous-soluble macromolecules, including peptides, proteins, synthetic polymers, and nanomaterials thereof, which exhibit a range of functionalities that can inhibit biofilm formation or detach and destroy organisms residing within established biofilms. In this Review, we outline the progress made in inhibiting and removing biofilms using macromolecular approaches, including a spotlight on cutting-edge materials that respond to environmental stimuli for "on-demand" antibiofilm activity, as well as synergistic multi-action antibiofilm materials. We also highlight materials that imitate and harness naturally derived species to achieve new and improved biomimetic and biohybrid antibiofilm materials. Finally, we share some speculative insights into possible future directions for this exciting and highly significant field of research.
Topics: Anti-Infective Agents; Antimicrobial Cationic Peptides; Biofilms; Drug Carriers; Macromolecular Substances; Methicillin-Resistant Staphylococcus aureus; Nanoparticles; Polymers; Pseudomonas aeruginosa
PubMed: 33403373
DOI: 10.1039/d0cs00986e -
Trends in Microbiology Oct 2019Active bacterial metabolism is a prerequisite for optimal activity of many classes of antibiotics. Hence, bacteria have developed strategies to reduce or modulate... (Review)
Review
Active bacterial metabolism is a prerequisite for optimal activity of many classes of antibiotics. Hence, bacteria have developed strategies to reduce or modulate metabolic pathways to become tolerant. This review describes the tight relationship between metabolism and tolerance in bacterial biofilms, and how physicochemical properties of the microenvironment at the host-pathogen interface (such as oxygen and nutritional content) are key to this relationship. Understanding how metabolic adaptations lead to tolerance brings us to novel approaches to tackle antibiotic-tolerant biofilms. We describe the use of hyperbaric oxygen therapy, metabolism-stimulating metabolites, and alternative strategies to redirect bacterial metabolism towards an antibiotic-susceptible phenotype.
Topics: Adaptation, Physiological; Anti-Infective Agents; Bacteria; Biofilms; Drug Resistance, Bacterial; Genetic Heterogeneity; Hyperbaric Oxygenation; Metabolic Networks and Pathways; Phenotype
PubMed: 31178124
DOI: 10.1016/j.tim.2019.05.003