An enzyme to destroy biofilms

One can not stop the progress. The discovery of an enzyme capable of preventing the production of a biofilm, this polymeric protective layer produced by bacteria that prevents antibiotics and surface disinfectants from functioning well, could ultimately revolutionize the fight against nosocomial infections.

perturbation-biofilm

The team at the McGill University Health Center, which includes Dr. Donald C. Sheppard, has published a study in the journal Proceedings of the National Academy of Sciences (PNAS). Their hope is that this technology will be the subject of human clinical trials in Canada within 5 years and be used in hospitals within 10 years.

From the abstract:

We demonstrate that glycoside hydrolases derived from the opportunistic fungus Aspergillus fumigatus and Gram-negative bacterium Pseudomonas aeruginosa can be exploited to disrupt preformed fungal biofilms and reduce virulence.

What is a biofilm?

My colleague Rémi Charlebois described biofilms as follows:

Biofilms found on surfaces are often derived from a complex colony of microorganisms producing polymers that allow them to adhere better to the surface and facilitate colony life. In short, a biofilm is like a city for microbes. Man has learned to tame these biofilms and can use them to treat wastewater or produce certain molecules such as natural plastics. However, the presence of unwanted biofilms could be harmful and can lead to infections.

Biofilms are also found on the skin and medical devices. Thus, according to the article of Le Devoir:

Biofilms, a highly sticky matrix of proteins and sugar polymers made by bacteria to protect themselves, are attached to the skin, mucous membranes or the surface of biomedical materials, including catheters, tubing, heart valves and other prostheses Which become preferred entry points for infection.

In the same article, Dr. Sheppard quotes:

Biofilms are produced by molecules that defend against our immune system or against antibiotics with this shell that is 1000 times more resistant than the organisms that produce and proliferate in these biofilms.

An enzyme that acts as a “destructive machine” for biofilms

In short, the enzyme discovered was modified to destroy the biofilms instead of forming them. This is a new strategy that can reduce nosocomial infections in healthcare centers.

Watch this video about biofilms (25 minutes, french)

Sources:

http://www.ledevoir.com/societe/sante/501939/des-chercheurs-percent-le-secret-de-la-resistance-de-certaines-bacteries

http://www.lapresse.ca/sciences/medecine/201706/27/01-5111114-avancee-majeure-contre-les-infections-dans-les-hopitaux.php

Biofilms: What you should know.

Biofilms are everywhere

Well hidden or sometimes visible, always disgusting, biofilms, as so well described by my colleague Rémi Charlebois, are defined as follows:

Biofilm is an aggregation of microbial cells, surrounded by a protective layer of extracellular polymeric matrix, which attaches itself to any surface found in the hospital environment and becomes a source of contamination. Formation of complex, multicellular communities by microorganisms is a natural phenomenon which helps bacteria or fungi to survive environmental stress such as cleaning and disinfection.

Warning: Graphic Content Ahead

A Biofilm looks like this:

Kitchen Drain

biofilms-drain-cuisine

Source: http://www.biofilm.montana.edu/content/household-biofilms

Sink strainer

biofilm-bouchon-evier

Source: http://www.biofilm.montana.edu/content/household-biofilms

Showerhead

biofilm-pommeau-douche

Source: http://www.biofilm.montana.edu/content/household-biofilms

Toilet Bowl

biofilm-cuve-toilette

Source: http://www.biofilm.montana.edu/content/household-biofilms

How to remove biofilms

Here are 3 methods to eliminate biofilm:

Replace equipment

This mehode is somewhat drastic, probably very expensive certainly mostly impractical. Some industries still proceed that way in 2016. I must say that in some cases it may be the only and best solution. For example pipe sections, filters, etc.

Strong acids and bases

Hydrochloric or Peracetic acids or strong bases such as caustic are sometimes used alternatively. However, corrosivity and danger of these chemicals can damage surfaces, individual protection equipment, storage and handling can also be a challenge . Furthermore, there is always the workplace hazards.

Biofilm: The Next Big Thing in Disinfection

biofilm

The Next Big Thing in Disinfection: Biofilm

Have you ever wondered what are the main factors affecting the efficacy of disinfection and sterilization in the healthcare facility? U.S. Centers for Disease Control and Prevention lists seven major causes of microbiological persistence on surfaces:

  1. Number of microorganisms
  2. Microbial resistance to biocides
  3. Concentration and Potency of Disinfectants
  4. Duration of Exposure
  5. Chemical and Physical Factors
  6. Presence of Organic or Inorganic Matter
  7. Biofilms

For many experienced healthcare professionals, these factors are well known and often well dealt with. However, did you know the difference between soil (organic and inorganic matter) and biofilm? They both can significantly lower the efficacy of disinfection, but the biofilm is much harder to remove and control.

What is biofilm and how does it form?

Biofilm is an aggregation of microbial cells, surrounded by a protective layer of extracellular polymeric matrix, which attaches itself to any surface found in the hospital environment and becomes a source of contamination. Formation of complex, multicellular communities by microorganisms is a natural phenomenon which helps bacteria or fungi to survive environmental stress such as cleaning and disinfection.

Many pathogens require a presence of conditioning layer made from organic soil to settle and start extracellular matrix synthesis. But there are bacteria which don’t really need much help to start a biofilm community. When pathogens settle down and surround themselves in an extracellular polymeric substance (EPS), they are much harder to kill.

It has been reported that bacteria found in biofilm can be up to 1,000 times more resistant to biocides than their planktonic counterparts.

How to outsmart and fight biofilm?

Despite biofilms’ rigid structure and resistance mechanisms, biofilm cells can still be outsmarted. Since EPS is the ultimate protective barrier and communication route for pathogens, the control of biofilm should start with disruption of the EPS itself, followed by an application of a biocide.