Biofilms

Question 1

What are the specific functios of the extracellular polymeric substance matrix (EPS matrix)?

Answer 1

To protect the bacterial community from environmental stressors (e.g. immune system, antibiotics, etc.), to facilitate waste removal and to retain nutrients.

Question 2

What are the 5 stages of biofilm formation?

Answer 2

1. Signals are sent out via quorum sensing to trigger biofilm formation. 2. Microbes create weak,reversible bonds (e.g. van der Waals) to the surface. 3. Microbes begin to create the extracellular polymeric substance matrix (EPS matrix), this step is irreversible. 4. The microbes undergo binary fission and expand the population. 5. The EPS matrix develops into a complex three-dimensional structure – cells in the biofilm may start differentiating into specialised roles.

Question 3

Why are biofilms a problem in for example catheters or replacement joints?

Answer 3

1. The biofilm adheres very tightly/strongly to the surface, making them hard to remove in comparison to bacteria not in a biofilm. 2. Biofilms make the bacteria resistent to antibiotics and generally well protected, meaning they can cause treatment-resistent infections

Question 4

True or false: biofilms are usually diverse and consist of many different fungi, bacteria and other microbes

Answer 4

True

Question 5

Why does plaque build up on teeth quicker if you eat foods with refined sugar?

Answer 5

Plaque is a biofilm, and many bacteria use carbohydrates such as refined sugar for food. When there is an excess of food bacteria thrive and reproduce faster.