Biofilm... the bacterial colony

Bacteria first appeared on earth about 3.6 billion years ago, long before the appearance of Homo sapiens around 100,000 years ago.. Van Leeuwenhoek was the first person to visualize, graphically illustrate, and label "animalcules" (bacteria) that he found in plaque scraped from his own teeth.
A biofilm is an aggregate of microorganisms in which cells are stuck to each other and/or to a surface. These adherent cells are frequently embedded within a self-produced matrix of extracellular polymeric substance (EPS). Biofilm EPS, which is also referred to as "slime," is a polymeric jumble of DNA, proteins and polysaccharides.
A biofilm is a complex aggregation of microorganisms growing on a solid substrate. Biofilms are characterized by structural heterogeneity, genetic diversity, complex community interactions, and an extracellular matrix of polymeric substances.
More properly known as biofilm , slime cities thrive wherever there is water - in the kitchen, on contact lenses, in the gut linings of animals. When the urban sprawl is extensive, bio films can be seen with the naked eye, coating the inside of water pipes or dangling slippery and green from plumbing ." (Coghlan 1996)
Biofilm are a common mode of bacterial growth in nature and their presence has an enormous impact on many aspects of our lives, such as sewage treatment, corrosion of materials, food contamination during processing, pipe collapse, plant-microorganisms interaction in the biosphere, the formation of dental plaque, the development of chronic infections in live tissue (mastitis, Otitis, pneumonia, urinary infections, osteomyelitis) or problems related to medical implant
Formation of a biofilm begins with the attachment of free-floating microorganisms to a surface. These first colonists adhere to the surface initially through weak, reversible van der Waals forces. If the colonists are not immediately separated from the surface, they can anchor themselves more permanently using cell adhesion structures such as pili
Indwelling medical device when contaminated with microorganisms, several variables determine whether a biofilm develops. First the microorganisms must adhere to the exposed surfaces of the device long enough to become irreversibly attached. The rate of cell attachment depends on the number and types of cells in the liquid to which the device is exposed, the flow rate of liquid through the device, and the physicochemical characteristics of the surface
Bacteria living in a biofilm can have significantly different properties from free-floating bacteria, as the dense and protected environment of the film allows them to cooperate and interact in various ways. One benefit of this environment is increased resistance to detergents and antibiotics, as the dense extracellular matrix and the outer layer of cells protect the interior of the community
Microbial biofilms, which often are formed by antimicrobial-resistant organisms, are responsible for 65% of infections treated in the developed world.
Dental plaque is a yellowish biofilm that build up on the teeth. If not removed regularly, it can lead to dental caries.
Additionally, through the growth process of the plaque bio film, the microbial composition changes from one that is primarily gram-positive and streptococcus-rich to a structure filled with gram-negative anaerobes in its more mature sta
Cell-cell signaling (ex. quorum sensing ), and communication with different bacteria enhance Biofilm formation
They're everywhere: on your shower curtain, on medical devices implanted in patients, on rocks in rivers and streams, and in your nose. While the sheer number of different organisms a biofilm may contain makes it a challenge to study,
Biofilms form on the surface of catheter lines and contact lenses. They grow on pacemakers, heart valve replacements, artificial joints and other surgical implants. The CDC ( Centers for Disease Control ) estimate that over 65% of Nosocomial (hospital-acquired) infections are caused by biofilms.
Bacteria growing in a biofilm are highly resistant to antibiotics, up to 1,000 times more resistant than the same bacteria not growing in a biofilm. Standard antibiotic therapy is often useless and the only recourse may be to remove the contaminated implant.
Another area of great importance from a public health perspective is the role of biofilms in antimicrobial-drug resistance. Bacteria within biofilms are intrinsically more resistant to antimicrobial agents than plank tonic cells because of the diminished rates of mass transport of antimicrobial molecules to the biofilm associated cells or because biofilm cells differ physiologically from plank tonic cells
Antimicrobial agents are administered during valve replacement and whenever the patient has dental work to prevent initial attachment by killing all microorganisms introduced into the bloodstream. As with biofilms on other indwelling devices, relatively few patients can be cured of a biofilm infection by antibiotic therapy alone
Role of biofilms in multiple pathologies and the difficulty in resolving these pathologies speaks to the importance of developing means of replacing or enhancing the therapies already in use. The use of synthetic materials in the body ranges from catheters to mesh to stents to heart valves and beyond. Until the development of viable and practical tissue engineering, then number and types of applications in which synthetic materials are used will continue to increase.
Several researchers are finding solutions for the cure of Biofilms , yet it is experimental, with advances in molecular biology better model treatments can be identified to reduce the problem of Biofilm interference in Antibiotic therapy.