How Biofilms Work

By: Marianne Spoon

Tools to Battle Biofilms

The largest problem with biofilms is that they seem to form on areas that are either difficult to access or too delicate to treat. Removing a catheter infested with biofilm bacteria and replacing it with a new one will do the trick; but what about people who depend on their artificial heart valve to survive?

Finding answers isn't easy. Depending on the biofilm, some can be scraped off gently while others may have a strong enough attachment to corrode the surface they call home. And despite your previous success with pressure washing your home or using water flow to rid yourself of dirt, increasing the water flow from your faucet will not peel off biofilms. Sure, you'll remove some cells in the short run, but the biofilm will become accustomed to the higher fluid shear, and will grow a thinner, but more tenaciously attached biofilm in the long run [source: Sturman]. Even if you succeed in removing a biofilm by force, how can you ensure you evict every last cell?


This is why researchers study biofilms at the molecular level. They want to know which conditions will make different species of microbes detach from the biofilm colony and surface. Scientists are coming closer to understanding this relationship in some species already. In one study, researchers found a specific protein that seemed to control detachment in a few types of bacteria [source: Davies et al.]. Similarly, other researchers focus on finding the genes that allow cells to attach to a surface or biofilm in hopes they may reveal how to detach microbes or even weaken their cell matrix to increase the effectiveness of antimicrobials.

Research efforts also concentrate on ways to implant medical devices while reducing biofilm infections. The prevailing idea is that using a combination of techniques may work depending on the species in the biofilm and the condition of the patient. If you want to do your own part in preventing microorganisms from spreading in medical environments, make sure to wash your hands, avoid touching patients unnecessarily and listen to medical staff members about what you can do to help keep the spread of microbes down.

Perhaps the largest weapon against unwanted biofilms is preventing them from colonizing in the first place. Keeping surfaces clean is always a step in the right direction.

Ultimately, it's important to realize that until the appearance of advanced microscopes, very little was known about biofilms. Now, these colonies are being studied in depth by thousands of scientists in different disciplines around the world. We still have a long way to go, but researchers are working hard to answer biofilms' toughest questions. Any discovery enhances our knowledge of these fascinating colonies and brings us closer to controlling biofilms and using them for the better.

For more resources on biofilms, check out the next page.

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