![]() extracellular DNA (e-DNA) and polysaccharides. EPS is composed mainly of a complex mixture of proteins, lipids, nucleic acids i.e. Biofilm formation is an important virulence mechanism in the pathogenesis of many medically important organisms such as Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, etc infections including biofilm formation such as vaginitis, colitis, gingivitis, otitis, urethritis, etc īiofilms are communities of bacteria embedded in the EPS matrix. īiofilms can grow on surfaces of many medical implants such as sutures, catheters, dental implants, etc. Some of the literature revealed that microbial biofilms are involved in sewage purification also. Microorganisms in biofilm help in the production and degradation of organic matter, remediation of environmental pollutants, nitrogen cycle, sulfur, and many metals. Extracellular enzymatic activities in EPS assist the detoxification of heavy metals by transforming and subsequently participating in exopolymeric mass. EPS as being poly-anionic in nature, forms complexes with positively charged metals (cations) result in metal immobilization within the exopolymeric network. Biofilm has been used for the remediation of heavy metals for a long time. Biofilms are considered beneficial as these degrade hazardous substances which are present in the soil, but are detrimental to food and slaughterhouse equipment and are also found responsible for the pathogenesis of a number of diseases. Biofilms appear either beneficial or detrimental. īiofilms are found to be present on liquid surfaces as floating mat and in a submerged state as well. The substances produced by these microbes are known as extracellular polymeric substances (EPS) result in the alteration in the phenotype of the organism with respect to growth rate and gene transcription. Biofilm contains a group of microorganisms irreversibly attached to and grow on a surface. Bacteria try to switch this planktonic form to biofilm due to a number of advantages which includes protection against environmental stresses such as extreme pH, oxygen, osmotic shock, heat, freezing, UV radiation, predators, etc. Planktonic forms are the free-living forms of bacteria. Biofilms are different from the planktonic form of bacteria. Biofilms are the group of microorganisms living within a self-produced matrix of polymeric substances which get attached to several surfaces. This is possible due to the development of biofilm. Microorganisms exist in nature primarily attached to biotic and abiotic surfaces. This article discusses the biofilm structure, phenomenon of biofilm formation, signaling, and pathogenicity to highlight the understanding of processes involved in biofilm formation. QS and EPS make the bacteria resistant to various antibiotics, which make the eradication difficult and hence requires more effective treatment. QS involves a two-component signaling process which is different for both Gram-positive and Gram-negative bacteria. Bacteria respond to these AIs results in an alteration of gene expression, which results in the release of various virulence factors. ![]() AI concentration increases as the bacterial population increases. In QS, bacteria produce various signaling molecules called Auto-inducers (AI). QS is the regulation of gene expression in bacteria with respect to changes in cell population density. In biofilms, cells communicate via Quorum Sensing (QS). ![]() Biofilms can be monospecies or multispecies. Biofilm formation is a five-step process. These EPS substance makes it difficult to eradicate the biofilm present on the surface. These biofilms live in a self-sustained matrix and produce different substances called extracellular polymeric substances (EPS) which are responsible for the pathogenicity of a number of bacteria such as Pseudomonas aeruginosa, Staphylococcus aureus, Vibrio cholerae, Klebsiella pneumoniae, Escherichia coli, etc. ![]() Biofilms are the communities of microorganisms, especially bacteria attached to a biotic or abiotic surface. ![]()
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